PM-PdM Technology for Manufacturing Industries

How to get the most out of your CMMS

2010-08-12T00:35:00.001+08:00

Experience shows there are three key groups that must buy in on the initial selection of a computerized maintenance management system (CMMS) and then the ongoing use of the system. Common to each of these groups is an understanding of their culture and the environment in which the system will be used. This is critical to CMMS success.

1) Maintenance: Technicians must see the CMMS as a tool that will help them do a better job, be more efficient and improve work processes. It can't be viewed as a system management is using to "watch them" or give the perception that someone always is peering over their shoulder.

Because technicians will use the CMMS daily, they will grow to depend on it. Early acceptance is important and buy-in during the initial evaluations is critical. Their CMMS will become an integral tool that they learn to rely on and trust in for helping them do their jobs to their best abilities as maintenance professionals every day.

2) Equipment users: Production and engineering personnel must see the value CMMS delivers for prompt and effective maintenance. These are the resources responsible for producing product and generating output; therefore, their lines must operate at their highest levels as much as possible. Preventive maintenance must be coordinated with production and unplanned maintenance must be performed quickly so as not to impact production.

Personnel at the equipment level will be able to recognize the value of a CMMS and understand that proactive maintenance on critical equipment is essential. Having the right CMMS tool that enables maintenance pros to do this work is key.

3) Management: People in management roles should view the CMMS as a means of obtaining metrics regarding maintenance deployment and equipment performance. Through reporting on work performed, planned and in process, management can improve its decision-making process. Having updated information on equipment maintenance history and relative maintenance cost enables management to control resources and costs more effectively. The right CMMS must be able to provide the data management needs for this process.

Bringing these groups together during the selection and implementation planning stages will set the tone for ongoing CMMS success. Such a process will also encourage user input to help determine the type of system that is the best fit for the company. This should take into account the size of organization that will be using the CMMS, functionality required, facility type, budget and return on investment. These components will influence how an organization will achieve the desired results from a CMMS.
IMPLEMENTATION
Software will not "implement itself." Unfortunately, many companies aren't deriving much benefit from their CMMS because the system has been poorly implemented. By taking a systematic approach to the CMMS implementation, organizations will be on a better path for success.

Database building must be planned and checked for effectiveness at predetermined steps. It is essential to have one person actively involved and in charge to ensure proper implementation. Many implementations fail because the database hasn't been built systematically; several people have entered their own data without direction as to what is needed or expected, resulting in a system that only can be used by the implementer. Proper implementation consists of building the database to match the environment (data formats, how data is recorded, manipulated and managed) and developing a systematic use of the CMMS that is consistent on a daily basis.

Training on how to use the CMMS is often a key component of implementation and provides a disciplined approach to best system usage. It also provides a means for educating multiple users across different disciplines on how to use the system for each of their areas.

CONCLUSION
Software alone won't improve how an organization handles maintenance. System users must understand how the CMMS works and how it can be trusted as a tool to improve work processes and effectiveness. Maintenance, equipment users and management all should view a CMMS as a means for controlling costs and increasing capacity. Having this mind-set is a huge step toward getting the most from a system.

Source: www.benchmate.com.

Predictive Maintenance (PdM) and Preventive Maintenance (PM)

2010-08-10T23:50:00.000+08:00

One of the employee ask me, What is the difference between Preventive Maintenance (PM) and Predictive Maintenance (PdM)?

Here's an straight answer:

"The distinction between preventive maintenance (PM) and predictive maintenance (PdM) is that PdM tracks performance based on conditions while PM is a time-based replacement or service process"

The question now is... what is the best between these two?

Static and dynamic testing as part of PdM programs

2010-08-10T22:55:00.000+08:00

by Timothy Thomas, Baker Instrument Company

Predictive maintenance programs (PMPs) are becoming universally accepted as the best method for maintaining motor reliability within most modern plants and facilities. A complete PMP will include as many technologies as possible, with each technology providing vital pieces to the diagnostic puzzle. Periodic static testing and more aggressive dynamic testing of motors are essential parts of predicting the potential for a motor to continue a safe and successful operation. Tracking and trending the results of electric motor testing on a regular schedule is the most effective method of making intelligent predictions.

The need for motor testing

The steady, safe and efficient operation of electric motors is essential to the productivity of all plants and facilities. Some facilities have many critical and/or expensive motors. A motor failure could be catastrophic, causing lost production and costly emergency repairs. For example, a motor failure at a nuclear plant can cost up to $1 million a day for critical motors and may have a disastrous, long-lasting impact. Even failures at a wastewater treatment facility can have a huge, negative environmental effect and can be very costly.

Motors fail due to numerous operational circumstances, including power condition, mechanical influences and environmental hazards. According to IEEE1 and EPRI2 studies, at least 35 to 45 percent of motor failures are electrically related. Monitoring the motors “electrical health” is, unquestionably, an important and vital consideration.

Trending the historical operating condition of a motor makes early detection of any decline in the motors “health” possible. Planning downtime and having only minor reconditioning repairs instead of a major rewind or replacement is far less expensive in both repair costs and lost production. Since electric motors begin deteriorating the instant they are started, it is necessary to monitor their operating condition on a routine, periodic schedule. Periodic monitoring and trending of data collected and properly diagnosed provides the technician with evidence needed to prepare for downtime before a catastrophe occurs.

It is no longer practical to just “megger” a motor in order to determine its condition. Plants and facilities depend on a complete predictive maintenance program (PMP) to monitor their operations and plan their repair schedules. A good PMP requires both static (and off-line) and dynamic (or on-line) testing, with educated and trained technicians monitoring data routinely, with quality equipment.

Besides voltages and currents, on-line test equipment must be able to capture and trend torque ripple and torque signatures as well as rotor bar sidebands. Off-line testing with modern, high-voltage test equipment is essential to getting reliable data. The voltages required to properly test motor windings cannot be reached with impedance-based or low-voltage test equipment.

On-line testing

Effective dynamic test equipment must be able to collect and trend all essential data that affects the operation of electric motors. Power condition – including voltage level, voltage imbalance and harmonic distortions, current levels and current imbalances, load levels, torque signatures, rotor bar signatures, service factors and efficiencies – should be tracked and trended.

On-line testing is performed at the motor’s MCC, at the load side of a variable frequency drive or at an installed port, which allows for on-line testing without opening the MCC. Data is collected through a set of current transformers and corresponding voltage probes. The data collected, processed and analyzed provides the technician with an overall view of the normal operational environment to which the motor is subjected on a daily basis and of how the motor is responding within this environment.

Often, a motor is subjected to incoming power problems including low or high voltages, voltage imbalances and harmonic distortions. Lower voltages cause higher currents and, therefore, more heat. Higher voltages cause lower power factors and ultimately higher losses. A small amount of voltage imbalance creates an exponential amount of current imbalance which causes temperature increases. Harmonic distortion also causes thermal stress in motors. Any of these voltage problems can cause severe overheating in the motor even without factually reaching an over-load situation, and excessive heat is the insulation’s major enemy. Some motors are subjected to physical obstacles that cause undue stress. Over-greasing, misalignment and over-tightened belts all cause thermal stress.

Many motor failures can be traced to load related situations. Erratic torque signatures can be an indicator of load-related problems. Broken or cracked rotor bars also can cause premature motor failures. On-line testing identifies these problems, and routine trending will reveal the rate of decline. Of major importance to the overall health of a motor also is the “effective service factor.” Two elements affect the service factor number are: real operating power condition (voltage quality) and steady state load conditions. The effective service factor number represents the thermal stress caused by these two conditions on the motor. On-line testing can find and trend all of these motor conditions.

Dynamic testing schedules should be tailored individually according to operating time, criticality and any other important element of operation. Generally, an on-line test should be performed at least quarterly. Motors that begin to show obvious decline or thermal over-stressing should be monitored more closely until the motor can be statically tested or removed from operation and repaired. New and recently repaired motors should be tested as soon as they are returned to service in order to provide a historical record (or baseline) of their performance when the motor is at its “best.”

Off-line testing

In general, motors are quite reliable, and when properly maintained, you should expect at least 100,000 hours of continual operation. That is to say, a new motor operated within nameplate parameters should give us at least 11 years of steady use. Unfortunately, motors are almost always subjected to a variety of damaging elements, with the end result being a rise in operating temperature. Thermal aging of the insulation is the major cause of insulation failure. Years of testing and numerous studies have shown that, as a “rule of thumb,” “for every 10 degrees centigrade increase in temperature, the winding life is decreased in half.”3

Besides thermal problems, other causes of insulation failures include incoming line related problems. Spikes caused by lightning and surges created by switching and contactor closing contribute to insulation breakdown. Motors also are subjected to mechanical influences including bearing failure, environmental hazards and magnet wire damage caused during the manufacturing process. Even the physical movements of the windings during startups causes wear to the insulation system, especially the magnet-wire insulation, as D.E. Crawford has shown.4

Proper testing of all components of a motor requires a series of tests designed to emulate the conditions the motor will see in the field. It has been proved in numerous studies that low-voltage testing, including capacitance, inductance, impedance, etc., are not effective tools in verifying insulation problems. Quality off-line test equipment will be able to perform winding resistance tests, insulation-resistance tests, high-potential (HiPot) tests, polarization index, and surge tests at IEEE, NEMA and EASA accepted standards. Top-quality test equipment will automatically run a series of preprogrammed tests and provide a complete final report.

This automatic equipment will stop testing before any damage is done to the windings.

The resistance test verifies the existence of dead shorts within the turn-to-turn coils and shows any imbalances between phases due to turn count differences, along with locating poor wire connections or contacts and finds open parallel coils.

DC insulation resistance testing detects faults in ground wall insulation or motors that have already failed to ground. Weak ground wall insulation (prior to copper-to-ground failure) can only be found successfully with the HiPot tests. The ground wall insulation system consists of the magnet wires insulation, slot liner insulation, wedges, varnish and often phase paper. DC HiPot test should be performed at twice line voltage plus 1,000 volts since motors will see voltage spikes of at least that level during each startup. HiPot testing is necessary to verify winding suitability for continued service.

Surge testing detects faults in both inter-turn winding and phase-to-phase insulation systems. Turn-to-turn faults will not be seen by a megger or HiPot test. Potential faults can only be seen when the coils see more than 350 volts from turn-to-turn or coil-to-coil, as described by Paschen’s Law 5 (Figure 1). The typical mechanism of fault progression is a turn-to-turn short, causing excessive heat and progressing within seconds or minutes to copper to ground faults. Faults are much more likely to occur between turn-to-turn winding coils due to the added stress caused by bending and exaggerated during the winding process. The ground wall insulation is generally many times stronger and more capable of withstanding voltage spikes and other stresses.

Figure 1.

Conclusions

Integrating on-line and off-line testing into a predictive maintenance program provides the technician with verification of his motor’s condition (see case studies below). Both technologies are necessary in order to have a complete picture of a motor’s health.

Collecting both on-line and off-line data on a routine schedule allows for early warning of impending failures and opens the opportunity window for planned downtime. Performing resistance, HiPot and surge testing along with dynamic testing provides the technician with a total picture of the motor’s condition and allows him or her to track its rate of decline.

Modern test equipment includes enhanced and detailed reporting. Reports are easily generated, providing a written hard copy of test results and making diagnosing and comparing of data clearer and more accurate. Setting up and managing a program to monitor the motors within any facility is essential to insure the safe and continued operation and production of the facility. In most cases, a properly managed and operated PMP will save a plant or facility much more than it will cost to implement, administer and manage.

Case studies

1) At a large wastewater treatment facility in Florida, 14 identical motors were scheduled for predictive maintenance. These motors were 40-horsepower aerators for a large treatment tank and operated continuously. Static tests were performed on all 14, and each received passing marks on all tests. When dynamic testing was complete, it was noted that 13 motors were acting very similar running within expected parameters at approximately 85 percent load, while the 14th motor was running at just over 30 percent load. Further inspection revealed a sheared coupling on the motor running at reduced load. The operators had no way of detecting the problem, and the location of these motors made visual inspection difficult. The dynamic testing found a problem that was costing the customer both in wasted kilowatt usage and production.

2) Twelve 60-horsepower pump/motors were tested at a large office building. Six were chilled water pump/motors and six were condenser water circulating pump/motors. All 12 were installed at the same time and ran continuously. Dynamic testing was performed one day on all 12, and all appeared to be operating within expected parameters. The motors were shut down for a scheduled annual routine building maintenance, and static testing was planned for the following morning. Resistance tests appeared normal on all, but two would not pass HiPot testing at the preset voltage. Three others failed the surge tests. The five motors were removed from service, disassembled and inspected. Two were found to be extremely dirty, while three had no visual damage. All five were reconditioned, retested and replaced in service. The off-line testing prevented five potential catastrophic failures and allowed the customer to dictate the downtime.

Source: reliableplant.com

Embedded Condition Monitoring and Remote Diagnostics Prevent Equipment Failure, Reduce Energy Consumption, Improve Reliability

2010-08-08T23:10:00.000+08:00

By Adam Krug

Only a very small percentage of critical motors and motor loads in the U.S. actually are equipped with any sort of condition monitoring. This lack of adoption largely stems from the costs and complexity of conventional condition monitoring equipment.

Industry-leading solid-state, motor control technology provides customers with the ability to monitor parameters, albeit not the exact same parameters, to gain a more precise and real-time perspective on performance, far more simply than traditional condition monitoring methods.

For the purposes and scope of this discussion, condition monitoring makes use of sophisticated technologies and tools to assess equipment condition, so as to predict potential equipment failure. Condition monitoring is a key element of predictive maintenance and enables scheduled maintenance. Fundamentally, it aims to prevent equipment failure and the spectrum of associated costs.

Imminent damages or failure is identified by a deviation from an established reference value. While condition monitoring does not directly predict failure, it identifies machinery or equipment that is failing or imperfect; equipment with latent problems is at greater risk for failure. Further, it is typically more cost effective to address conditions that could cause failures, rather than cleaning up once a failure has occurred.

Employing new intelligent overload relays as a supplement to traditional condition monitoring provides customers with a cost-effective means to increase the percentage of assets covered by condition monitoring within a facility. This helps end users protect more equipment from a pending motor or load failure, on loads that otherwise would have been left unmonitored. Ultimately, this means:

* Improved uptime
* Reduced maintenance costs per repair
* Reduced energy consumption

Traditional approach

Condition monitoring typically includes the following technologies: Vibration sensors, pressure transducers, RTDs and other means of measuring temperature, infrared scopes, and other various sensors to record performance data.

Traditional implementation requires sensors to be mounted on motors and pumps and then hardwired back to a device to gather the data, such as a centralized computer system. This data then needs to be interpreted by trained personnel, who are able to understand the output from these sensors. Ultimately, traditional condition monitoring methods are complex and costly.

Typically, this data is gathered continuously and logged in a central computer, or it is taken by teams of inspection crews, who record performance readings on a set schedule. In most instances, inspection crews are trained specifically on signal processing and sensor analysis and typically outsourced to a third party. Whether facilities outsource these teams to third parties or have in-house personnel dedicated to spot inspections, there are significant costs and opportunity costs associated with such methods.

Moreover, motors and pumps are not all conveniently located; many are in hard-to-access areas and can require more than one inspector to comply with OSHA regulations. When trained professionals perform their analysis from a remote location, the data is required to be streamed and passed through an IT firewall or transmitted via an outside modem.

All of that said, the traditional approach to condition monitoring can be largely effective. But, due to the costs and complexity involved, this type of attention is typically reserved for only the most critical and expensive capital equipment. Most users calculate the value of the asset as the capital costs of replacement, as well as the effect that asset has on productivity and throughput.

The lack of implementation of traditional condition monitoring despite its value is evident in a U.S. Department of Energy (DOE) study on motor monitoring practices. According to a recent study on critical loads, the U.S. manufacturing sector has nearly 32M motors rated 500 horsepower (HP) or less. Of the 141,000 motors driving pumps, fans, and compressors, only 1% has monitoring today; these are typically motors rated at 200HP or more. In other words, there are a high percentage of critical loads at low horsepower where condition monitoring is not being used. The result is unscheduled downtime or inefficient operation of equipment, which translate into:

* Reduced throughput
* Environmental fines
* Energy waste
* Higher maintenance costs
* Increased capital expenditure
* Reduced profitability

Notably, downtime costs, maintenance costs, and energy usage are critical concerns for end-users, according to an Eaton Survey. Further, according to a similar study by the DOE, there is the potential for tremendous cost avoidance; if users added monitoring to their motors and pumps, they could recognize an aggregate, annual $23 billion of energy cost avoidance.

A means for greater asset coverage

Increased adoption of advanced motor overload relays and fieldbus communications is game changing; it allows for greater system reliability and tremendous potential for cost and energy savings. The starter-based technology is “sensorless” and nonintrusive. Further, a starter is necessary with every motor installation. Simply put, advanced overload and monitoring relays provide a cost-effective solution, with greater motor coverage for condition monitoring. They yield performance data and energy usage information that can be monitored and acted upon either by personnel or control schemes within the higher level plant systems.

Maintenance optimization

With intelligent pump, motor, and line quality monitoring, customers are able to eliminate unnecessary inspections and only send personnel when data indicates an issue. With an understanding of the fault type or pending fault type, the right person with the appropriate skill set can be deployed to address specific issues. In other words, if a clog is detected, a 40-year veteran need not be sent to address the issue at hand; send individuals with appropriate experience and expertise to address defined issues. Additionally, an understanding of fault type enables personnel to come equipped with the appropriate tools; costly second trips are avoided, and service time is reduced. Simply put, optimized maintenance means:

* Scheduled downtime
* Eliminate unnecessary inspections
* Optimized labor skill sets
* Reduced service time

Armed with a remote look at the performance of their motors, customers are able to optimize maintenance and reduce costs. Motor or pump operation can be checked from any computer in a plant or facility, and even from home. Trending data collection allows for the detection or prediction of potential motor failure conditions. Further, when conditions are indicative of an imminent failure, customers are able to switch to spare or secondary motors or pumps and avoid downtime.

Low power conditions

Though much of the discussion to this point has been regarding the advanced overload relays’ ability to provide remote data monitoring, the goal of this data is to prevent failure of an asset. Overload relays can act on their own data with a high degree of flexible protection settings. One such setting not widely associated with overload relays is low power protection.

Low power conditions, where real power provided to the motor falls below normal operating conditions, can cause mechanical failure and/or excessive heating by running a pump in dead- headed or starved condition—damaging expensive seals and ultimately failing the pump. New overload relays are able to detect low power conditions with protective fault settings and avoid associated costs and downtime.

For example, an under power situation occurs when a pump continues to run against a mostly closed valve—overload relays can extend equipment life, reduce downtime, save energy, and reduce maintenance. Without the use of an advanced overload relay, the pump would continue to run because a float limit switch would not drop—as the water level would not decrease. A second pump would likely be turned on to compensate. And so, two pumps would be running and performing the work of one pump, essentially. In the meantime, the seal of the first pump would be heat-aging, shortening its usable life. Today, such a situation can be monitored, detected, and avoided. Wasted run-time hours can be avoided, with the protective-fault, under power feature. The overload relay would take the first motor offline, and the second pump would come online and complete the pumping activity—the first pump would be saved from doing non-value add work. Further, the wear on components would be reduced; the overload relay would have taken the first pump offline, preventing the heat-aging of the seal. Energy consumption would be reduced, as only one motor would be running (instead of two). Maintenance is reduced by avoiding the unnecessary use of equipment.

Driving, delivering energy savings

In the U.S., motors use approximately 71% of the electrical energy in a typical industrial facility. The large population of motors in the 20 to 300HP range are consuming the majority of the energy. Little monitoring (less than 1%) is done on low horsepower motors.

Overload relays able to monitor energy and power factor are able to:

* Avoid peak demand charges
* Shed non-vital loads
* Identify and rectify increased consumption
* Identify discrepancy between equal loads
* Identify power factor line items

Overload relays with advanced monitoring and flexible communications capabilities allow customers to observe abnormal and inefficient operation in real time. For across-the-line loads, today’s overload relays are able to do more than protect the motor. They allow customers to see consumption at the specific load and facilitate real-time equipment monitoring. Using industry protocol communications and central SCADA systems, customers can catch increased consumption in real time and control consumption and avoid downtime; situations can be rectified before extra energy costs are incurred. Commands over the fieldbus allow remote shutdown of non-vital assets, while side-by-side comparisons of similarly sized assets and comparisons made over time enable the identification of inefficiencies.

As many plants must run continuously, it is critical to be able to prevent equipment failure and scheduled downtime to address detected problems. Continuously monitoring key failure indicators with remote monitoring solutions helps facilities respond to equipment problems sooner. The early detection of system degradation—through condition monitoring and predictive diagnostics—is critical to productivity and the bottom line. To gain greater asset coverage, overload relays with advanced remote monitoring capabilities can supplement traditional condition monitoring methods—and yield significant energy and cost savings, while improving system reliability and reducing maintenance.

To meet new energy efficiency standards, many facilities will need to adopt and implement new and existing technologies, including VFDs, advanced overload relays with on-board electronic metering and monitoring, and asset management products to help make informed decisions that can improve operational efficiency. To propel energy efficiency, it is critical to provide support, education, and training for plant operators, engineers, and production workers.

Consequently, the increased demand for remote monitoring, advanced control methods, condition monitoring, and predictive diagnostics is not surprising. Customers are increasingly seeking devices that save energy, optimize their maintenance schedules, and provide greater system protection to reduce overall costs and downtime. Remote monitoring devices allow customers to monitor conditions in hard-to-access areas, trend in real-time motor conditions that could otherwise go unnoticed, and dispatch maintenance personnel before a problem occurs. Motor control system design focuses on power optimization and extended equipment life. Remote monitoring of asset conditions allows for optimal and timely predictive maintenance actions to prevent equipment failure and inefficient operation.

Source: www.isa.org

Vibration Testing and Thermal Imaging Technology

2010-08-06T22:16:00.003+08:00

Here's an article about vibration testing technology and thermal imaging technology. I find it really amazing hearing some companies using it and living through it, keeping it as part of their predictive maintenance technology in their manufacturing and operation.

Vibration Testing Technology

To the savvy maintenance professional, industrial machinery almost "talks" to reveal its condition. The key to success is in understanding what the machine is saying. To detect problems, the professional "listens" in many ways: With eyes and ears, to see and hear conditions that may indicate problems and...

With thermometers and thermal imagers, to detect overheating, poor electrical connections or failing bearings
With digital multimeters and power analyzers, to diagnose electrical problems
Using techniques like lubricant analysis, to gauge machine condition over time

And now new vibration testing tools provide the maintenance professional with a valuable new way not just to listen, but to find mechanical problems and fixes: these new troubleshooting tools are engineered to detect and evaluate machine vibration immediately and recommend any needed repairs.

A new kind of troubleshooting tool

Many industrial maintenance teams today work under severe restrictions on money and time. They may not have the resources to train for and implement the typical long-term vibration analysis program. Further, many professionals may think there are only two options for vibration testing; high-end vibration analyzers that are expensive and difficult to use, and low-end vibration pens, which aren't particularly accurate.

Fortunately, a new breed of vibration-testing tool fills the middle of the category, combining the diagnostic capability of a trained vibration analyzer with the speed and convenience of lower-end testers, at a reasonable price. This type of tool is designed to be not merely a vibration detector, but a complete diagnostic and problem-solving solution, and targeted specifically for maintenance professionals who need to troubleshoot mechanical problems and quickly understand the root cause of equipment condition.

These tools are designed and programmed to diagnose the most common mechanical problems of unbalance, looseness, misalignment and bearing failures in a wide variety of mechanical equipment, including motors, fans, blowers, belts and chain drives, gearboxes, couplings, pumps, compressors, closed coupled machines and spindles.

Not just data, but actionable results

When these new testers detect a fault, they identify the problem, its location and severity on a multi-level scale to help the maintenance professional prioritize maintenance tasks. They may also recommend repairs.

Mechanical diagnosis can begin with the user placing the device's accelerometer on the machine under test. The accelerometer may have a magnetic mount or can be installed using adhesive. As the machine under test operates, the accelerometer detects its vibration along three planes of movement (vertical, horizontal and axial) and transmits that information to the tester. Using a set of advanced algorithms, the tester then provides a plain-text diagnosis of the machine with a recommended solution.

No training? No problem

Mechanical equipment is typically evaluated by comparing its condition over time to an established baseline condition. Vibration analyzers used in condition-based monitoring programs rely upon these baseline conditions to evaluate machine condition and estimate remaining operating life. System operators must have considerable training and experience before they can determine the meaning and significance of the vibration spectra they detect.

But what about the maintenance pro who isn't trained in vibration analysis? How do you tell the difference between acceptable vibration, and the kind of vibration that demands immediate attention to service or replace troubled equipment?

Fortunately, extensive experience with mechanical vibration, what it means and how to fix it is built into the advanced algorithms of today's testers. Now the maintenance professional can quickly and reliably determine the cause of the machine vibration, learn the severity and location of the problem and receive recommendations for repair. It's all done with the intelligence built into the tester, without the extensive training, monitoring and recording required for typical vibration monitoring programs.

Now Lets talk about things about thermal imaging technolgy.

About the Thermal Image Camera

Having a thermal image camera can be quite beneficial. There are a lot of individuals who are opting for thermal imaging nowadays. Thermal imaging is quite great for analysis and problem solving. The great thing about thermal image camera is that it is quite easy to carry with you and it gives great performance. This can be attributed to the fact that it produces great thermal pictures due to its high resolution thermal detectors. It can be like having a normal digital camera but with more benefits.

When you are planning to purchase your own camera that has thermal imaging one has to consider some pointers in finding a quality one. One has to look a camera that has a high resolution. It is also wise to note the pixels output of the camera. This feature is very important for the temperature ability of the camera.

Secondly, accuracy should be an important feature of your choice of camera. An accuracy of 3% to 5% is what you should look for. Another feature that should consider is its temperature range. You have to take into account the weather conditions in your area. Whether you a hot or cold climate, this can really create a problem with the pictures it will produce.

A camera that has thermal imaging is being widely used by law enforcers. It helps them detect things that are quite seen by the human eye and this is a valuable asset for the law enforcement departments. Even plumbing and pest control areas have a great use for this type of camera. It helps them detect problems where they can not quite see or is obstructed from view.

Of course, the price of a thermal imaging camera is an important factor in buying it. You can usually buy a camera that has thermal imaging at around $3000. This is the model that is being used by a lot of professionals. The more features it has would mean that it would be more expensive. The best thing to do is to do a little bit of research and do price comparisons. You can great deals and bargains if you know where to look.

Source: Zara Jones and Steve Glad

Can smart instruments help Predictive Maintenance?

2010-01-19T13:02:00.002+08:00

Predictive Maintenance do really needs modern instrument or can smart instruments really help Predictive Maintenance? This question pulls together the entirely unrelated concepts of smart instruments, and predictive maintenance. The smart instruments (sometimes also called “smart sensors”) concept is a hardware-architecture strategy. Predictive maintenance, on the other hand, is a system-level concept.

Smart instruments have been around for a decade or more. The technology falls under the general heading of “embedded systems,” which includes any device containing a microcomputer, but no fully developed user interface. Examples include automotive engine control modules (ECMs); microprocessor controls for major appliances, such as dishwashers, microwave ovens, etc.; and mobile systems, such as cellphones and digital cameras. Smart instruments include one or more sensors to make physical measurements, a microprocessor to partially analyze sensor data, on-board memory to hold parameters and intermediate results, and I/O capabilities to report results to the next level of automation. Components for such devices are packaged together and mounted as close as possible to the point of measurement.

Predictive maintenance strategies monitor selected variables that engineers believe have maintenance-predictive power. For example, a rise in a bearing’s temperature may warn of impending need for additional or replacement lubricant. Automatically monitoring such variables makes it possible for the system to tailor the maintenance program to the machinery’s actual needs, saving time, supplies, and replacement parts, and avoiding unplanned work stoppages. The alternative is scheduled maintenance, which generally provides more maintenance than necessary on average, but may miss extraordinary events.

For example, a system described by engineers at SKF provides automatic bearing lubrication based on predictive maintenance principles. Traditional scheduled-maintenance calls for a technician to apply a certain amount of oil at set intervals. The schedule is (theoretically) based on historical data about how rapidly that type of bearing uses lubricant under the prevailing use conditions. Being statistical in nature, that data may over- or under-predict the needs of a particular bearing. In addition, even experienced technicians tend to apply more lubricant than necessary, which can actually harm the equipment. Failures can occur when the particular bearing uses lubricant at a rate significantly slower or faster than average. In the first case, too much lubricant would be applied. In the second, too little.

Physical phenomena associated with impending requirements for bearing lubrication are temperature rise and increased bearing noise (vibration). A smart instrument monitoring bearing temperature and noise can tailor the maintenance program to the particular bearing. It can automatically report a pattern of increasing operating temperature coupled with increased bearing noise appears. Maintenance personnel can then use this information to predict when lack of lubrication will begin damaging the bearing, and schedule a technician to apply lubricant just ahead of the danger point. This manual system reduces lubricant requirements, protects equipment more effectively, and reduces unscheduled downtime. Because maintenance operations still occur infrequently (typically at longer intervals than with scheduled maintenance because safety margins can be reduced), however, more lubricant than necessary is typically added at each maintenance, leading to some waste.
Smart-instrument-based predictive maintenance
Smart sensors can help make an automated system for bearing lubrication.

In SKF’s automated system, maintenance personnel do not schedule the lubrication visit, but the condition-monitoring computer automatically controls a microvolume pump to add oil in small quantities until the temperature and noise begin to trend down. When these parameters drop within specifications, the pump stops adding lubricant. This strategy applies just the needed lubrication when it’s needed, independent of the bearing’s peculiarities. By adding lubricant frequently in very small quantities, it is possible to keep the lubricant level very close to optimum. This reduces waste to a minimum by virtually eliminating overlubrication, and eliminates downtime for lubrication entirely.

The automated bearing lubrication system is just one example of a well-developed automated system based on predictive maintenance principles. Predictive maintenance systems based on monitoring physical parameters are actually quite common today. As embedded system techniques and smart sensors become more common in control applications, look for more instances of automated maintenance systems.

Source: www.controleng.com/blog | August 18, 2008

5S Process in Reliability Improvement

2010-01-17T15:46:00.002+08:00

The 5-S process is a method for ensuring workplace cleanliness, order and organization and should be at the heart of any reliability improvement initiative. It consists of five fundamental steps:

Sort— Get rid of accumulated junk that has no value to the job at hand. In Maintenance, this includes removing everything that does not add value to the work being done — components from broken machinery, unrepaired spare assemblies and tools, obsolete charts and graphs and "abandoned-in-place" equipment and piping systems. If it is not needed for the job at hand, it needs to be eliminated.
Straighten— Organize what remains after the first step. Consider the flow of work through the area and position equipment and storage facilities to eliminate lost motion and wasted travel. A craftsperson should not have to search for a tool or move something out of the way to begin work.
Scrub/Shine— Workplace cleanliness is the next step. Precision work requires a clean work environment. Shop spaces used to rebuild equipment should approach "clean room" standards. Remove all dust, dirt and contamination. Seal concrete floors so that spills are easily cleaned. Repair lighting fixtures and paint the work area with light colors — a brightly lit work environment is much more likely to remain clean. Deteriorating equipment conditions are more easily spotted when not covered by contamination.
Standardize— When the workplace is clean and organized, it must be kept that way. A system should be put into place that ensures the condition of the work area does not degrade. Visual controls can be used at the equipment level — registration marks on fasteners, color coding correct operating ranges on gauges and matched marking assemblies are examples.
Sustain— A process for conducting audits on a regular basis should be considered. When management shows a concern for workplace condition, it is much more likely to remain in good shape. Every employee must understand the need for safety, order and cleanliness. The facility should be kept in "tour condition" at all times.

The cleanliness must be performed so you won’t have to work in an unsafe, disorganized area which puts you at risk or even in danger. Since 5-S is for you, you also have an obligation and the responsibility to help prepare the tools and make sure they are in the proper place so that you can begin your job on time and efficient. Clean-up and organize your work area every day so that each new day is easier and safer than the day before. Share your input with your leaders so that the tools you need will be available to you, increasing your efficiency. Volunteer to help with the 5-S tours and resolve issues that are noted.

Total Productive Maintenance Implementation

2010-01-14T20:13:00.000+08:00

To begin applying TPM concepts to plant maintenance activities, the entire work force must first be convinced that upper level management is committed to the program. The first step in this effort is to either hire or appoint a TPM coordinator. It is the responsibility of the coordinator to sell the TPM concepts to the work force through an educational program. To do a thorough job of educating and convincing the work force that TPM is just not another "program of the month," will take time, perhaps a year or more.

Once the coordinator is convinced that the work force is sold on the TPM program and that they understand it and its implications, the first study and action teams are formed. These teams are usually made up of people who directly have an impact on the problem being addressed. Operators, maintenance personnel, shift supervisors, schedulers, and upper management might all be included on a team. Each person becomes a "stakeholder" in the process and is encouraged to do his or her best to contribute to the success of the team effort. Usually, the TPM coordinator heads the teams until others become familiar with the process and natural team leaders emerge.

Total Productive Maintenance action teams are charged with the responsibility of pinpointing problem areas, detailing a course of corrective action, and initiating the corrective process. Recognizing problems and initiating solutions may not come easily for some team members. They will not have had experiences in other plants where they had opportunities to see how things could be done differently. In well run TPM programs, team members often visit cooperating plants to observe and compare TPM methods, techniques, and to observe work in progress. This comparative process is part of an overall measurement technique called "benchmarking" and is one of the greatest assets of the TPM program.

TPM teams are encouraged to start on small problems and keep meticulous records of their progress.
Successful completion of the team's initial work is always recognized by management. Publicity of the program and its results are one of the secrets of making the program a success. Once the teams are familiar with the TPM process and have experienced success with a small problem, problems of ever increasing importance and complexity are addressed.

As an example, in one manufacturing plant, one punch press was selected as a problem area. The machine was studied and evaluated in extreme detail by the team. Production over an extended period of time was used to establish a record of productive time versus nonproductive time. Some team members visited a plant several states away which had a similar press but which was operating much more efficiently. This visit gave them ideas on how their situation could be improved. A course of action to bring the machine into a "world class" manufacturing condition was soon designed and work was initiated. The work involved taking the machine out of service for cleaning, painting, adjustment, and replacement of worn parts, belts, hoses, etc. As a part of this process, training in operation and maintenance of the machine was reviewed. A daily check list of maintenance duties to be performed by the operator was developed. A factory representative was called in to assist in some phases of the process. Total Productive Maintenance was just the right fit for the situation

After success has been demonstrated on one machine and records began to show how much the process had improved production, another machine was selected, then another, until the entire production area had been brought into a "world class" condition and is producing at a significantly higher rate.

Note that in the example above, the operator was required to take an active part in the maintenance of the machine. This is one of the basic innovations of TPM. The attitude of "I just operate it!" is no longer acceptable. Routine daily maintenance checks, minor adjustments, lubrication, and minor part change out become the responsibility of the operator. Extensive overhauls and major breakdowns are handled by plant maintenance personnel with the operator assisting. Even if outside maintenance or factory experts have to be called in, the equipment operator must play a significant part in the repair process. Training for TPM coordinators is available from several sources. Most of the major professional organizations associated with manufacturing as well as private consulting and educational groups have information available on TPM implementation. The Society of Manufacturing Engineers (SME) and Productivity Press are two examples. Both offer tapes, books, and other educational material that tell the story of TPM. Productivity Press conducts frequent seminars in most major cities around the United States. They also sponsor plant tours for benchmarking and training purposes.

Total Productive Maintenance History

2010-01-13T20:00:00.002+08:00

Total Productive Maintenance (TPM) evolved from Total Quality Management (TQM,) which evolved as a direct result of Dr. W. Edwards Deming's influence on Japanese industry. Dr. Deming began his work in Japan shortly after World War II. As a statistician, Dr. Deming initially began to show the Japanese how to use statistical analysis in manufacturing and how to use the resulting data to control quality during manufacturing. The initial statistical procedures and the resulting quality control concepts fueled by the Japanese work ethic soon became a way of life for Japanese industry. This new manufacturing concept eventually became knows as Total Quality Management or TQM.

When the problems of plant maintenance were examined as a part of the TQM program, some of the general concepts did not seem to fit or work well in the maintenance environment. Preventative maintenance (PM) procedures had been in place for some time and PM was practiced in most plants. Using PM techniques, maintenance schedules designed to keep machines operational were developed. However, this technique often resulted in machines being over-serviced in an attempt to improve production. The thought was often "if a little oil is good, a lot should be better." Manufacturer's maintenance schedules had to be followed to the letter with little thought as to the realistic requirements of the machine. There was little or no involvement of the machine operator in the maintenance program and maintenance personnel had little training beyond what was contained in often inadequate maintenance manuals.

The need to go further than just scheduling maintenance in accordance with manufacturer's recommendations as a method of improving productivity and product quality was quickly recognized by those companies who were committed to the TQM programs. To solve this problem and still adhere to the TQM concepts, modifications were made to the original TQM concepts. These modifications elevated maintenance to the status of being an integral part of the overall quality program.

The origin of the term "Total Productive Maintenance" is disputed. Some say that it was first coined by American manufacturers over forty years ago. Others contribute its origin to a maintenance program used in the late 1960's by Nippondenso, a Japanese manufacturer of automotive electrical parts. Seiichi Nakajima, an officer with the Institute of Plant Maintenance in Japan is credited with defining the concepts of TPM and seeing it implemented in hundreds of plants in Japan.

Books and articles on TPM by Mr. Nakajima and other Japanese as well as American authors began appearing in the late 1980's. The first widely attended TPM conference held in the United States occurred in 1990. Today, several consulting companies routinely offer TPM conferences as well as provide consulting and coordination services for companies wishing to start a TPM program in their plants.

Lean maintenance and its many faces

2010-01-12T21:52:00.005+08:00

What Lean Maintenance is all about?

Lean Maintenance is the application of Lean philosophy, tools and techniques to the maintenance function. It has the same goals as the application of Lean principles to the manufacturing function: eliminating wasted time, effort and material (and resulting cost) while improving throughput and quality.

As Lean Manufacturing seeks to provide products at the highest quality at the lowest cost in the shortest possible time, Lean Maintenance provides the same attributes to the maintenance function. In fact, Lean Manufacturing depends highly on reliable systems and equipment to achieve its potential.

Lean does not imply cutting the fat or eliminating jobs. It is not an attempt to reduce cost through headcount reductions, which typically don't have anything to do with reducing work. Lean organizations reduce costs by eliminating activities that don't add value to the product stream. It means reassigning people and resources from unnecessary work to value-adding work.

Many tools used to implement Lean principles in manufacturing operations also apply to implementing Lean Maintenance. These tools include:

• 5-S process
• Elimination of the Seven Deadly Wastes
• Kaizen
• Jidoka (Quality at the Source)
• JIT (Just in Time).

I came across in this article some years ago, I think that was 2005. That was during the time I am searching about Lean Maintenance. I like the idea on Lean Maintenance but I never heard this term (Lean Maintenance) in our company department but I assure that we're practicing its application.

Source: Bruce Hawkins, CMRP, CPMM, Life Cycle Engineering | Plant Engineering

Successful Predictive Maintenance (PdM) Programs Depend on Consistency

2010-01-07T08:12:00.003+08:00

The following is an except from the article entitled "Choose Your PdM Partners Wisely Or Discover Another Reason Why PdM Programs Can Fail" by Alan Friedman, appeared on reliabilityweb.com

One reason many in-house programs fail is a lack of consistency on many levels. A successful Predictive Maintenance (PdM) program relies on long-term consistency on the technical level in terms of collecting repeatable data for trending. This means that assets must be tested the same way time after time, year after year, in terms of test speeds, loads, test positions, test types etc. Consistent testing ensures accurate trending of machine condition, the development of meaningful baselines and alarm criteria and, therefore, accurate fault diagnosis and repair recommendations. This is very different from the process of using the technology to troubleshoot an asset. Troubleshooting is a valid use of these technologies, but does not result in a change in maintenance philosophy, nor does it provide the large ROI’s such a change in philosophy should produce.

On a higher level, such technical consistency also depends on the reliability of management and personnel. Oftentimes, due to lack of financial justification, PdM programs are stopped and personnel are reassigned to different tasks. New maintenance managers may not understand the technology and may recommend a new approach to using – or not using – it which disrupts the consistency of a program. In-house “experts,” in seeking to keep their jobs secure, may not document or follow fixed procedures for monitoring equipment or share information with others, causing programs to fail when they leave for greener pastures.

There are many reasons why programs bloom and then decay. People who have different ideas about how Predictive Maintenance (PdM) should be done come and go, priorities change, technology changes, expertise changes and approaches change. The one sure thing is that all of these starts and stops and changes in direction ensure a program will never be successful. This is another reason why an external partner is a good option to keep the program running steadily regardless of what is happening within the maintenance department of your facility.

In general, it can be said that a good Predictive Maintenance program requires a consistent approach, with a clear set of objectives that can be measured to monitor the success or failure of the program. The program must continue to remain consistent through good times and bad, regardless of who in the facility (or outside the facility) is running the program, collecting data, analyzing it or writing reports. This sort of consistency is often difficult to maintain within a facility, and is an example of where a good partnership with a Predictive Maintenance service provider can be a huge asset. Especially if this partner has a long track record of managing successful PdM programs and has a well-defined approach to managing such programs. This is different from hiring a vibration expert to come on-site at times to troubleshoot machines or structures.

But why choose your Predictive Maintenance (PdM) partners wisely? Here's his conclusion:

Whether you are considering starting a new program, revamping a dead one, outsourcing or looking for someone to become a long term partner to step in when needed and step back when not needed, make sure you pick the correct partner. The company should have a good track record of managing successful programs, should use good equipment for the job, and should make necessary equipment available to you as part of a sale or service or as a lease as needed. Make sure your partner can train staff at all levels, from using the products to analyzing graphs, but, more importantly, is capable of managing your particular program and answering specific questions related to auditing your program. The importance of helping you calculate the economic impacts of these technology and maintenance practices to your bottom line can not be underestimated.

More than anything, consider that choosing the right partner may make the difference between a consistent and effective program that runs smoothly over the next ten or twenty years and an endless series of false starts and investments in misused equipment. One thing is for sure, successful programs, more often than not, involve good partners.

To read the full article click here: Choose Your PdM Partners Wisely

Reliability Centered Maintenance Advantage and Disadvantages

2010-01-06T19:02:00.000+08:00

Reliability centered maintenance (RCM) is the maintenance approach used when following a process that assesses equipment condition and determines the maintenance requirements of any physical asset in its operating context.

Basically, the RCM methodology addresses key issues not dealt with by other maintenance programs. This approach recognizes that all equipment in a facility is not of equal importance—to either the process or to facility needs and safety. Focusing on reliability of equipment means recognizing that equipment design and operations differ, and that each piece of equipment will have a different probability of undergoing failure from degradation than will another. A reliability-focused approach will mean structuring a maintenance program based upon the understanding of equipment needs and priorities, as well as limited financial and personnel resources, to plan activities such that equipment maintenance is prioritized while operations are optimized.

Simply put, RCM is a systematic approach of evaluating a facility's equipment and resources to best match the two needs. This results in a high degree of facility reliability and cost-effectiveness, and is highly reliant on predictive maintenance. However, it also recognizes that maintenance activities on equipment that is inexpensive and less important to overall facility reliability may be best left to a reactive maintenance approach, focusing both labor and financial resources on higher priority and more costly equipment. The following maintenance program breakdowns of continually top-performing facilities echo the RCM approach, which utilizes all available maintenance tactics. As is shown, all maintenance approaches are used, but the predominant strategy used is predictive.

<10%>
25% to 35% Preventive
45% to 55% Predictive

Because RCM is so heavily weighted on utilization of predictive maintenance strategies, its program advantages and disadvantages mirror those of predictive maintenance. In addition to these advantages, RCM will allow a facility to more closely match its resources to operational needs and at the same time improve both reliability and also reduce associated maintenance costs.

Advantages

Can be the most efficient maintenance program
Lowers costs by eliminating unnecessary equipment maintenance or system overhauls
Minimizes the frequency of overhauls
Reduces probability of sudden equipment failures
Focuses maintenance activities on critical system components
Increases component reliability
Incorporates root cause analysis

Disadvantages

Can have significant startup costs associated with staff training and equipment needs
Savings potential is not readily seen by management

An Introduction to Total Productive Maintenance (TPM)

2010-01-06T13:17:00.003+08:00

What is Total Productive Maintenance (TPM)?
It can be considered as the medical science of machines. Total Productive Maintenance (TPM) is a maintenance program which involves a newly defined concept for maintaining plants and equipment. The goal of the TPM program is to markedly increase production while, at the same time, increasing employee morale and job satisfaction.

TPM brings maintenance into focus as a necessary and vitally important part of the business. It is no longer regarded as a non-profit activity. Down time for maintenance is scheduled as a part of the manufacturing day and, in some cases, as an integral part of the manufacturing process. The goal is to hold emergency and unscheduled maintenance to a minimum.

Why Total Productive Maintenance?
TPM was introduced to achieve the following objectives. The important ones are listed below.

Avoid wastage in a quickly changing economic environment.
Producing goods without reducing product quality.
Reduce cost.
Produce a low batch quantity at the earliest possible time.
Goods send to the customers must be non defective.

Similarities and differences between Total Quality Management (TQM) and Total Productive Maintenance (TPM):
The TPM program closely resembles the popular Total Quality Management (TQM) program. Many of the tools such as employee empowerment, benchmarking, documentation, etc. used in TQM are used to implement and optimize TPM.Following are the similarities between the two.

Total commitment to the program by upper level management is required in both programmes
Employees must be empowered to initiate corrective action, and
A long range outlook must be accepted as TPM may take a year or more to implement and is an on-going process. Changes in employee mind-set toward their job responsibilities must take place as well.

The differences between TQM and TPM is summarized below.

TQM
Object: Quality ( Output and effects )
Mains of attaining goal: Systematize the management. It is software oriented
Target: Quality for PPM

TPM
Object: Equipment ( Input and cause )
Mains of attaining goal: Employees participation and it is hardware oriented
Target: Elimination of losses and wastes.

Source: plant-maintenance.com | Venkatesh J

Predictive Maintenance Implementation: Advantages and Disadvantages

2010-01-05T06:53:00.000+08:00

A predictive maintenance approach strives to detect the onset of equipment degradation and to address the problems as they are identified. This allows casual stressors to be eliminated or controlled, prior to any significant deterioration in the physical state of the component or equipment. This leads to both current and future functional capabilities.

Basically, predictive maintenance differs from preventive maintenance by basing maintenance needs on the actual condition of the equipment, rather than on some predetermined schedule. Recall that preventive maintenance is time-based. Activities such as changing lubricant are based on time, like calendar time or equipment run time. For example, most people change the oil in their vehicles every 3,000 to 5,000 miles traveled. This is effectively basing the oil change needs on equipment run time. No concern is given to the actual condition and performance capability of the oil. It is changed because it is time.

This methodology would be analogous to a preventive maintenance task. If, on the other hand, the operator of the car discounted the vehicle run time and had the oil analyzed at some periodicity to determine its actual condition and lubrication properties, he or she may be able to extend the oil change until the vehicle had traveled 10,000 miles. This is the fundamental difference between predictive maintenance and preventive maintenance, whereby predictive maintenance is used to define needed maintenance tasks based on quantified material and equipment condition.

Advantages

Provides increased component operational life and availability
Allows for preemptive corrective actions
Results in decrease in equipment and/or process downtime
Lowers costs for parts and labor
Provides better product quality
Improves worker and environmental safety
Raises worker morale
Increases energy savings
Results in an estimated 8% to 12% cost savings over which might result from a predictive maintenance program

Disadvantages

Increases investment in diagnostic equipment
Increases investment in staff training
Savings potential is readily seen by management

There are many advantages of using a predictive maintenance program. A well-orchestrated predictive maintenance program will all but eliminate catastrophic equipment failures. Staff will then be able to schedule maintenance activities to minimize or eliminate overtime costs. And, inventory can be minimized, as parts or equipment will not need to be ordered ahead of time to support anticipated maintenance needs. Equipment will be operated at an optimal level, which will also save energy costs and increase plant reliability.

Past studies have estimated that a properly functioning predictive maintenance program can provide a savings of 8% to 12% over a program utilizing preventive maintenance strategies alone. Depending on a facility's reliance on a reactive maintenance approach and material condition, savings opportunities of 30% to 40% could easily be realized. In fact, independent surveys indicate the following industrial average savings resulted from initiation of a functional predictive maintenance program:

Return on investment: 10 times
Reduction in maintenance costs: 25% to 30%
Elimination of breakdowns: 70% to 75%
Reduction in downtime: 35% to 45%
Increase in production: 20% to 25%

The down side of using a predictive maintenance approach are its initial costs. The up-front costs of starting this type of program can be expensive. Much of the equipment requires expenditures in excess of $50,000. And, training of in-plant personnel to effectively utilize predictive maintenance technologies and practices will require substantial additional funding. And, beginning a predictive maintenance program requires an understanding of the facility's predictive maintenance needs and the approaches which need to be undertaken. It is also essential to have a firm commitment, by management and all facility staff and organizations, to make it work.

Preventive Maintenance (PM) Definition

2010-01-04T23:16:00.002+08:00

Preventive maintenance (PM) has the following meanings:

The care and servicing by personnel for the purpose of maintaining equipment and facilities in satisfactory operating condition by providing for systematic inspection, detection, and correction of incipient failures either before they occur or before they develop into major defects.
Maintenance, including tests, measurements, adjustments, and parts replacement, performed specifically to prevent faults from occurring.

While preventive maintenance is generally considered to be worthwhile, there are risks such as equipment failure or human error involved when performing PM, just as in any maintenance operation. PM as scheduled overhaul or scheduled replacement provides two of the three proactive failure management policies available to the maintenance engineer. Common methods of determining what PM (or other) failure management policies should be applied are; OEM recommendations, requirements of codes and legislation within a jurisdiction, what an "expert" thinks ought to be done, or the maintenance that's already done to similar equipment. However Reliability Centered Maintenance, provides the most rigorous and method to determine applicable and effective failure management policies - which may include PM tasks - for an item.

To make it simple:

Preventive maintenance is conducted to keep equipment working and/or extend the life of the equipment.
Corrective maintenance, sometimes called "repair", is conducted to get equipment working again.

The primary goal of maintenance is to avoid or mitigate the consequences of failure of equipment. This may be by preventing the failure before it actually occurs which PM and condition based maintenance help to achieve. It is designed to preserve and restore equipment reliability by replacing worn components before they actually fail. Preventive maintenance activities include partial or complete overhauls at specified periods, oil changes, lubrication and so on. In addition, workers can record equipment deterioration so they know to replace or repair worn parts before they cause system failure. The ideal preventive maintenance program would prevent all equipment failure before it occurs.

Source: wikipedia

Predictive Maintenance Program

2010-01-04T18:49:00.002+08:00

A Quality Rotating Machinery Predictive Maintenance (PdM) Program for your facility will return your investment many times over. This type of PdM Program is based on periodic vibration measurements of your Rotating Machinery. In many cases, a Return On Investment (ROI) of less than one year (six months typical) is quite common. A Contract PdM Program eliminates the initial capital investment required to conduct your own PdM Program.

There are three classifications of machinery maintenance methods: Breakdown, Preventative, and Predictive Maintenance. Each method has its own associated costs and benefits.

Breakdown Maintenance, by its own nature, is the most expensive method of plant maintenance. This method has no scheduled maintenance until a machine destroys itself, and it must be replaced at great cost. The machine breakdown often brings the production process to an immediate halt. Breakdown Maintenance has high costs in manpower, replacement parts, and lost production.

Preventive Maintenance, the next logical method, relies on a periodic inspection the machines. During the inspection, machine damage is found and corrected. This method requires a large inventory of replacement parts prior to the machine's inspection. Preventative Maintenance has a lower associated cost because manpower can be planned in advance.

Predictive Maintenance involves monitoring the machine's vibration characteristics or symptoms to diagnose its condition. This method relies on the machine's condition to accurately schedule the repair interval. The machine's condition also determines the required replacement parts. Predictive Maintenance has the lowest cost of the three methods with the highest possible savings.

A Machinery PdM Program is beneficial to all industries that have rotating machinery on their site such as:

Petroleum
Chemical
Power Generation
Co-Generation
Pulp and Paper
Water Treatment
Building Services
HVAC
Mining
Food Processing

Typical Rotating Machinery commonly included in a Machinery PdM Program include but are not limited to the following:

Electric Motors
Pumps
Fans
Gear Boxes
Turbines
Compressors
Paper Machines
Reciprocating Machines
Blowers
Machine Tools
Chillers
Conveyors

Vibration Analysis as Prognostic Maintenance Procedure

2010-01-03T02:10:00.001+08:00

Vibration analysis is becoming more and more well-known as a prognostic maintenance procedure as well as a support for machinery maintenance judgment and decisions. Generally, machines don't fail, malfunction, or break down without showing some symptoms or warning, which is often shown by an amplified level of vibration. To find out the nature and harshness of the machine flaw, and to therefore predict the failure of the machine or equipment, vibration measurement and analysis should be conducted.

A machine has an overall vibration signal that comes from the several components and structures infused into it. Mechanical problems, however, create distinctive vibrations at varying frequencies. And these defects as well as the natural frequencies of different structural elements can be diagnosed by analyzing the frequency and time range and employing signal processing skills.

Since vibration analysis deals with all moving components of any kind of rotating device, it can point out not just particular machine troubles but can also make repairs simpler by spotting the origin or root cause of the problem. And most significantly, vibration analysis is capable of discovering the flaws before they become evident. Hence, you will be warned of budding equipment problems, and you can allow your engineers or technicians to be ready for repairs and to make the repairs at a convenient time rather than during emergency situations.

Vibration analysis, which is done through a vibration analyzer, and some skill, can help a person point out the causes of coarse and irregular machinery conditions. Vibration analysis systems are really helpful for modal analysis and vibration testing.

When it comes to analysis requirements, vibration analysis is complicated and calls for human experience and capability. Nevertheless, it is an inexpensive and functional diagnostic means to guarantee a smoothly running machine.

Source: Ezinearticles | Elizabeth Morgan

Predictive and Preventive Maintenance in a Declining Economy

2010-01-02T23:04:00.001+08:00

In a declining economy saving operating expenses has become a priority for most firms. Predictive and preventive maintenance although similar, are two different tools used by facilities managers in order to save precious dollars. Both maintenance systems help keep earnings (the bottom line) stable by avoiding costly repairs and maximizing equipment up-time. Normally cutting expenses for operations means fewer support staff, hiring freezes, and a repair versus replacement strategy on equipment. But what happens when the forecast for low or declining sales does not improve or is mired in a deep recession?

A recent survey conducted by Facilities Planners and Architects, Inc. of facility managers and business owners revealed intended reactions to the current economic situation. The survey highlights are:

Limiting capital expenditures to sustainability initiatives such as more efficient lighting systems
More plans to reduce square footage
Outsourcing non-core services such as janitorial services
Assessing the condition of the facilities and better strategic planning of their use
Initiating predictive maintenance programs

Obviously, it is always a good idea to watch your expenses. The results echoes this and indicates a long overdue desire to become more energy efficient, a focus on core responsibilities by outsourcing non-core functions, a strategic look at assets and the initiation of efficiency and savings programs. The survey mentions predictive maintenance as one of the most popular choices for cost saving solutions. It should be noted that predictive maintenance is not the same as preventive maintenance. Successful predictive maintenance starts with preventive maintenance. To better understand let us take a look at both.

Predictive vs. Preventive Maintenance:

Preventive maintenance occurs on a pre-determined schedule and is intended to increase efficiencies by reducing the amount of reactive work and increasing the ability of management to manage work. Most importantly, it allows for the early identification of problems and significantly increases the life cycle of equipment, lowers capital expenditure requirements and allows for better planning of capital budgets. In addition, when integrated with handheld technologies and a combination of asset management, work order management and inspections, work flow efficiencies are increased to maximum levels. The data collected through this method becomes the building block for predictive maintenance.

Predictive maintenance does have its benefits in a difficult economy particularly because it can be less labor intensive than preventive maintenance. Predictive maintenance programs are based upon the actual condition of the equipment and a determination of when maintenance should be performed to minimize costs. New technology techniques such as ultrasound, infrared and vibration online testing make predictive maintenance a viable alternative in certain circumstances. However, for most equipment the complex metrics for making educated guesses is provided by preventive programs.

The goal of a facility manager or business owner is to make sure equipment has the highest possible uptime and to extend the life cycle of the equipment as long as possible at the most reasonable economical cost. Some predictive maintenance plans will require a capital investment in higher technology sensing equipment but most will be built upon the foundation and metrics provided by an existing preventive maintenance program. Facility managers should not rely on just a predictive maintenance solution to save expenses especially if dealing with high value equipment or if safety is at stake.

Tough times call for tough decisions as both maintenance programs have their place. The solution may be a combination of the two maintenance programs or it may be dependent on your industry, type of equipment and survival strategy. What is your company going to do?

Source: Mintek | http://EzineArticles.com/?expert=S_W_Smith

Facility Maintenance Management Software

2010-01-01T14:40:00.001+08:00

Facilities form the non-core services of a corporation or any organization. Non-core services can include managing administration function, property management, and managing contract services such as cleaning and security. A major portion of the assets of an organization is in the form of infrastructure, like buildings and equipment. Hence, the maintenance of physical assets is a major function of facilities management.

The role of facilities management is to help businesses concentrate in their core competent areas. Facilities management takes on the role of providing routine, non-value-added services which are essential and important for the effective running of an organization.

Facilities management in its widest sense can be applied to any industries. The industries range from public services such as schools, universities and parks, to private services such as manufacturing. Anything that can be outsourced to a third party can be termed as facilities.

Since most of functions of facilities are routine, the role and capacity of IT is precisely suited for that function. IT provides end-to-end solutions for an enterprise. ERP and EAM systems take on the role of MRP systems to streamline operations and help reduce costs.

Physical assets such as buildings, equipment and IT installations require regular maintenance; therefore, the role of IT in providing maintenance solutions is a major part of the portfolio of ERP providers. Maintenance is a major function of facilities. According to a study, properly planned and maintained services can lead to a 20 percent reduction in the operating cost of a firm.

The level and scope of functionality varies in the maintenance management system, according to the type of industries and physical assets. Therefore, except for standard functions like maintenance audits and down-time calculators, most of the software functionalities should be customized.

These are many software vendors available, each of whom has an internet presence. The futuristic vision of maintenance management systems is already implemented by some vendors who provide on-demand remote maintenance services, thereby reducing the costs of installing of maintenance systems further.

Source: Eddie Tobey | ezinearticles

Plant Engineering: Manufacturing Perspectives at Automation Fair

2009-12-31T23:15:00.003+08:00

This is from Bob Vavra of Plant Engineering. Read what he tells about manufacturing perspectives at automation fair.

1. The power of the plant floor:
The opening day of Rockwell Automation’s annual Automation Fair in Anaheim on Tuesday featured a day-long series of discussions on a global view of manufacturing issues. The morning session of the Manufacturing Perspectives series painted a strong picture of a manufacturing economy emerging from a deep recession and already showing signs of life with 2010 just around the corner.
It also pointed again to the power and visibility the plant floor is receiving from automation vendors, IT professionals and business leaders.

In his opening remarks Tuesday, Rockwell Automation CEO Keith Nosbusch pointed to the shift in manufacturing “from an IT-connected manufacturing system to an optimized plant floor and supply chain network. The plant floor is where power, control and information converge. The factory floor becomes the focal point.”

2. The globalization of manufacturing:
Nosbusch said that Rockwell’s goal was to have 60% of its business outside the U.S. by 2013. Already, he noted that more than half of Rockwell Automation’s employees are outside of the U.S.

While some of our more short-sighted commentators view this as “off-shoring” jobs, Jeremy Leonard of the Manufacturers Alliance/MAPI noted in his remarks that there is good off-shoring and bad off-shoring. “Most of the off-shoring is the former,” Leonard said. While conceding that high-value, low-piece products such as computers and electronics are manufactured to take advantage of labor costs, he said the vast majority of expansion in emerging markets such as China, Indian and Brazil is to serve the local and regional markets. He added that transportation costs have driven many manufacturers away from simply off-shoring jobs and production because of the increasing costs of getting those products back into the supply chain.

3. Issues and opportunities:
Leonard cited four major reforms manufacturers need to improve their operations - and all of them were legislative in nature: reducing tax rates (which he said was “the single most important barrier to competitiveness”) heath care costs, tort reform and regulatory compliance. But he also said American manufacturing suffers from lower levels of research and development than most other industrialized nations and are drawing on a smaller skilled labor pool. His research finds that U.S. engineering degrees are down 20% in the last two decades and that 40% of current 9th graders will lack the skills needed in modern manufacturing.

4. The good news is:
“The manufacturing recession is over,” Leonard said. While growth will slow in the fourth quarter because the stimulus packages, especially Cash For Clunkers, will not be present in the fourth quarter, MAPI is still anticipating 2.4% growth for the year and predicts slow but steady growth over the next five years. Build into that is a slower but still steady drop in the unemployment rate. But he does not see a lot of new construction in the coming months in manufacturing. “Plants will be putting idle capacity back on line rather than building new capacity,” he said.

5. And the quote: Leonard takes a dim view of those who claim U.S. manufacturing is not a major player in either the national economy or the global market. “U.S. manufacturing is the engine for growth in a global economy,” he said. “Manufacturing is not becoming less important to this economy. What matters is the volume of things made. We’re simply producing more with fewer resources.”

Maintenance Management: Contract Maintenance or Not? (Part 2 of 2)

2009-12-31T10:50:00.004+08:00

This is the continue of the series Maintenance Management: Contract Maintenance or Not? ; what kind of maintenance you should or should not contract out and the reasons why, as well as the characteristics of a good maintenance contract.

INCENTIVES AND GOALS. If you consider outsourcing maintenance, I advise you to set up a contract that includes an incentive for the contractor to continuously perform better.

SERVICE. If your contract is based on buying service alone, there is no real incentive for the contractor to perform better. The more hours they sell, the more money they make, and they can sell more hours if your maintenance needs are reactive. Only the fear of losing the contract will motivate the contractor to perform better.

RELIABILITY. If your contract is based on delivering results, you can create a win-win situation for yourself and the contractor. In most mills, results should be in the following order of priority after safety and environmental issues:

1. Reliability of equipment.
2. Cost of delivering reliability.

If there is an incentive for a contractor to deliver reliability, it naturally follows an incentive to prevent maintenance and to perform preventive maintenance, plan maintenance, schedule maintenance, and so forth. In summary, they need a disciplined process in place and a good system to support it.

In selecting a contractor, I suggest that you not only look at their rates, but that you spend the most time evaluating their maintenance philosophy (if they have one), what reliability and maintenance process they will implement, and how they will measure results. Go into detail on the basics of how they would decide whether to prevent—or not prevent—component failures, how planning will be done, how scheduling will be done, which key performance indicators will be used, continuous training of their people, and so forth. This is important, because you must remember that the only thing a contractor can do differently than you is that they can implement a more efficient work system. They can often do this quickly, or at least they can promise to do it quickly. Seldom will a contractor bring in a crew with superior skills to your own.

LONG-TERM CONTRACTS. A maintenance contract should be long term—no less than five years and preferably longer than that. There are many reasons for this. Two of them are included in what Dr. Deming called the seven deadly diseases common to U.S. management. They are “Lack of constancy of purpose” and “Mobility of top management.” My observation is that one phenomenon leads to the other. New managers are called in for fast and, unfortunately, often temporary results. They often change the organization, perhaps only because they want to bring in their buddies, make some cut backs, and then move on to another place before the long-term effects are noticed. The front line of the organization, where the actual actions of new directives have to take place, sees this as a constant change of direction. They start talking about the program of the month and, consequently, they do not change anything and the results of management efforts will be absent.

If this goes on for some time, no sustainable results will be achieved. In this situation, I think a long-term maintenance contract offers a possible solution. The contract has to be founded on the right principles and work processes, because, when these are not changed for a long period of time, your contractor can help eliminate the “lack-of-constancy-of-purpose phenomenon.” With good leadership, the work processes and your results should continuously improve. It could be done without a contractor, but not in a system where a new mill manager or maintenance manager means a new program.

HEALTHY COMPETITION. Almost without exception, maintenance departments have never had true competition. They have monopoly on most work in the mill. A contractor should be seen as a competitor to your own organization. As long as you are competitive, outsourcing of maintenance is not a valid alternative.

SKF Awarded Condition Based Maintenance Contract by Total

2009-12-30T12:39:00.003+08:00

STOCKHOLM, Sweden—SKF has been awarded a new five year condition based maintenance contract by Total E&P UK. In working globally with Total, SKF will in this contract provide condition based maintenance services covering a wide range of rotating equipment on Total’s North Sea onshore and offshore assets.

The contract covers in-depth vibration data analysis, lubrication oil analysis and equipment process analysis as well as other specialist investigations for Total. -This type of contract portrays the value added solutions SKF is able to offer in providing proven condition based maintenance solutions. SKF has the knowledge and the human resources to execute such challenges globally, says Vartan Vartanian, President of Service Division in SKF.

-We see our partnership with SKF as an important step in supporting our strategy of improving equipment reliability enabling us to reduce unplanned equipment downtime and helping with Total’s commitment to meeting safety, health, environment and quality requirements, says Alan Messié, Operations Manager, Total E&P UK.

Unplanned equipment downtime can result in a significant loss of production per day on a typical oil platform, which makes condition based monitoring an important tool to secure equipment reliability.

Total E&P is one of the principal exploration and production subsidiaries of the Total Group, which is the fifth largest publicly traded oil and gas company in the world.

Source: reliabilityweb | STOCKHOLM, Sweden

Predictive Maintenance Technologies

2009-12-30T11:03:00.000+08:00

To evaluate equipment condition, predictive maintenance utilizes nondestructive testing technologies such as infrared, acoustic (partial discharge and airborne ultrasonic), corona detection, vibration analysis, sound level measurements, oil analysis, and other specific online tests. New methods in this area is to utilize measurements on the actual equipment in combination with measurement of process performance, measured by other devices, to trigger maintenance conditions. This is primarily available in Collaborative Process Automation Systems (CPAS). Site measurements are often supported by wireless sensor networks to reduce the wiring cost.

Vibration analysis is most productive on high-speed rotating equipment and can be the most expensive component of a PdM program to get up and running. Vibration analysis, when properly done, allows the user to evaluate the condition of equipment and avoid failures. The latest generation of vibration analyzers comprises more capabilities and automated functions than its predecessors. Many units display the full vibration spectrum of three axes simultaneously, providing a snapshot of what is going on with a particular machine. But despite such capabilities, not even the most sophisticated equipment successfully predicts developing problems unless the operator understands and applies the basics of vibration analysis.

Acoustical analysis can be done on a sonic or ultrasonic level. New ultrasonic techniques for condition monitoring make it possible to “hear” friction and stress in rotating machinery, which can predict deterioration earlier than conventional techniques. Ultrasonic technology is sensitive to high-frequency sounds that are inaudible to the human ear and distinguishes them from lower-frequency sounds and mechanical vibration. Machine friction and stress waves produce distinctive sounds in the upper ultrasonic range. Changes in these friction and stress waves can suggest deteriorating conditions much earlier than technologies such as vibration or oil analysis. With proper ultrasonic measurement and analysis, it’s possible to differentiate normal wear from abnormal wear, physical damage, imbalance conditions, and lubrication problems based on a direct relationship between asset and operating conditions.

Sonic monitoring equipment is less expensive, but it also has fewer uses than ultrasonic technologies. Sonic technology is useful only on mechanical equipment, while ultrasonic equipment can detect electrical problems and is more flexible and reliable in detecting mechanical problems.

Oil analysis is a long-term program that, where relevant, can eventually be more predictive than any of the other technologies. It can take years for a plant's oil program to reach this level of sophistication and effectiveness. Infrared monitoring and analysis has the widest range of application (from high- to low-speed equipment), and it can be effective for spotting both mechanical and electrical failures; some consider it to currently be the most cost-effective technology. Analytical techniques performed on oil samples can be classified in two categories: used oil analysis and wear particle analysis. Used oil analysis determines the condition of the lubricant itself, determines the quality of the lubricant, and checks its suitability for continued use. Wear particle analysis determines the mechanical condition of machine components that are lubricated. Through wear particle analysis, you can identify the composition of the solid material present and evaluate particle type, size, concentration, distribution, and morphology.

Predictive Maintenance (PdM) Definition to the Next Level

2009-12-30T11:02:00.000+08:00

Predictive maintenance (PdM) techniques help determine the condition of in-service equipment in order to predict when maintenance should be performed. This approach offers cost savings over routine or time-based preventive maintenance, because tasks are performed only when warranted.

PdM, or condition-based maintenance, attempts to evaluate the condition of equipment by performing periodic or continuous (online) equipment condition monitoring. The ultimate goal of PdM is to perform maintenance at a scheduled point in time when the maintenance activity is most cost-effective and before the equipment loses optimum performance. This is in contrast to time- and/or operation count-based maintenance, where a piece of equipment gets maintained whether it needs it or not. Time-based maintenance is labor intensive, ineffective in identifying problems that develop between scheduled inspections, and is not cost-effective.

The "predictive" component of predictive maintenance stems from the goal of predicting the future trend of the equipment's condition. This approach uses principles of statistical process control to determine at what point in the future maintenance activities will be appropriate.

Most PdM inspections are performed while equipment is in service, thereby minimizing disruption of normal system operations. Adoption of PdM can result in substantial cost savings and higher system reliability.

Reliability-centered maintenance, or RCM, emphasizes the use of predictive maintenance (PdM) techniques in addition to traditional preventive measures. When properly implemented, RCM provides companies with a tool for achieving lowest asset Net Present Costs (NPC) for a given level of performance and risk.

Maintenance Management: Contract Maintenance or Not? (Part 1 of 2)

2009-12-30T10:39:00.002+08:00

This series article is from the Reliability and Maintenance Management Consultant Idhammar, who is also the president of IDCON, Raleigh, NC, a reliability and maintenance management consulting firm, specializing in education, training and implementation of improved operations, reliability, and maintenance management practices.

Think what he tells about whether we need a contract maintenance or not. This is what he think of contract, or outsourcing, of maintenance. In this article he elaborated on what kind of maintenance should or should not be contracted out and the reasons for choosing either option.

Variability in workload. The better you manage the workload of your own resources, the less need you will have for contract maintenance. In weekly and daily maintenance activities, your workload should not vary much if you have disciplined priorities and a good preventive maintenance system in place. Even areas such as maintenance workshops and scaffolding services should experience very few urgent requests, which justifies keeping only a minimum crew, if any at all, for such services in-house.

Large variations in workload will lead to poor utilization of resources and overstaffing. This often leads to discussions about contract maintenance. However, contracting maintenance resources will not change anything. The contractor must provide a better system for people to work in. Otherwise, they will not be more effective than your existing system. If this is the case, you must ask yourself why you cannot improve the system yourself when the contractor can.

The answer may be that you have tried many times without sustainable success. Your organization might be in gridlock because of politics, ingrained union practices, and so on. A situation like this can lead to an “act of desperation.” In other words, your organization has lost its power and ability to improve as fast as a contractor can (or at least promises to), so this becomes the reason why your maintenance is contracted out.

Temporary scheduled increase in workload.
During scheduled shutdowns and major outages, it is natural that you contract out work. It can be very cost-effective to not only contract the resources for executing the work, but to also have them plan and schedule major outages. However, periodic shutdowns—for example, every five to seven weeks—of a paper machine can, most probably, be managed better by your own shutdown planners.

Core business philosophy. Contract maintenance suppliers often argue, as a selling point, that maintenance is not a core business. Well, if you are a pulp and paper mill, or any other manufacturing plant, I would like to challenge that statement.

Why would maintenance not be a core business, while operations and manufacturing are considered core businesses? In fact, I believe that one of the best ways of approaching outsourcing is to have a manufacturing contract that is not limited to maintenance alone.

In looking at maintenance contracts alone, you should look upon “equipment reliability tasks” as a core business. You can always question if it makes good business sense to have your own carpenters, painters, people for scaffolding, masons, tinsmiths, and blacksmiths. Having the resources a phone call away and no invoice to explain will lead to more use of these resources than is needed. I sometimes wonder how many unnecessary paint jobs—and bookshelves, tables, and other carpentry work—have been done just because the resources were available and the requestor of the work did not need to pay the full cost of it.

Equipment reliability is the result of maintenance work, and it includes such essential elements as maintenance prevention, including lubrication, filtration, alignment, cleaning, and operating practices. It also includes preventive maintenance activities such as vibration analysis, basic inspections, and so forth. I believe all equipment reliability activities should be performed with in-house resources, unless you contract out all maintenance on an equipment reliability performance and cost basis.

Lack of skills. If your organization does not frequently use certain special skills, it is necessary to contract for these skills. Even if you train your own people in specialty skills, they cannot maintain them because they do not use them frequently enough.

The present and the future shortage of skilled craftspeople, especially in the U.S. pulp and paper industry, might be one of the best sales arguments for maintenance contract suppliers—if they have these resources to offer. Also, it is not unheard for unions to hold back their own members from receiving training. This fact has never made sense to me, since it should be in their interest to support training of members so that they are competitive with contractors.

Predictive Maintenance: A Short Introduction to Thermography

2009-12-14T07:55:00.000+08:00

To gain the maximum benefits from your investment in infrared systems, use it on critical systems that generate capacity in the plant

Thermography is a predictive maintenance (PdM) technique for monitoring the condition of plant machinery, structures and systems — not just electrical equipment. It uses instrumentation to read infrared energy emissions (surface temperature) to determine operating conditions. By detecting thermal anomalies (areas hotter or colder than they should be), an experienced technician can locate and define a multitude of incipient problems within the plant. Infrared technology works on the principle that objects having a temperature above absolute zero emit energy or radiation.

Infrared radiation is one form of emitted energy. Infrared emissions are invisible without special instrumentation. The intensity of infrared radiation from an object is a function of its surface temperature. However, measuring temperature with infrared methods is complicated, because three sources of thermal energy can be detected from any object: energy emitted from the object itself; energy reflected from the object; and energy transmitted by the object. Only emitted energy is important in a PdM program. Reflected and transmitted energies distort raw infrared data. Therefore, they must be filtered out of acquired data before meaningful analysis can be performed.

Variations in surface condition, such as paint or other protective coatings, can affect the actual emissivity factor for plant equipment. They may change, sometimes radically, both the surface temperatures and heat distribution recorded by the infrared scanner. If the technician fails to compensate this, it will be difficult, if not impossible to accurately diagnose the incipient problems. In too many cases, they will be missed and serious damage or catastrophic failure will occur.

In addition to reflected and transmitted energy, the user of thermographic techniques must consider the atmosphere between the object and the measurement instrument. Water vapor and other gases absorb infrared radiation. Airborne dust, some lighting and other variables can distort infrared radiation measurements. Because the atmospheric environment is constantly changing, using thermographic techniques requires extreme care each time data is acquired.

Most infrared monitoring systems or instruments use filters to eliminate the negative effects of atmospheric attenuation. However, the user must recognize the specific factors that will affect infrared data accuracy and apply the correct filters or other signal conditioning methods.

Collecting optics and radiation detectors are basic elements of an industrial infrared instrument. Optical systems collect radiant energy and focuses it upon a detector, which converts it into an electrical signal. The instrument’s electronics amplifies the output signal and process it into a form that can be displayed. Three general types of instruments are used for PdM: infrared thermometers or spot radiometers, line scanners and imaging systems.

Infrared thermometers

Infrared thermometers or spot radiometers provide the actual surface temperature at a single, relatively small point on a machine or surface. Point-of-use infrared thermometers are commercially available and relatively inexpensive. Their typical cost is less than $1,000.

Within a PdM program, the point-of-use infrared thermometer can be used in conjunction with many microprocessor-based vibration instruments to monitor the temperature at critical points on plant machinery or equipment. This technique is typically used to monitor bearing cap temperatures, motor winding temperatures, spot checks of process piping temperatures and similar applications. It is limited in that the temperature represents a single point on the machine or structure. However, when used in conjunction with vibration data, point-of-use infrared data can be a valuable tool.

Line scanners

Line scanners provide a single dimensional scan or line of comparative radiation. While this type of instrument provides a somewhat larger field of view (the area of machine surface), its use in PdM applications is limited.

Infrared imaging

Unlike other infrared techniques, thermal or infrared imaging provides the means to scan the infrared emissions of complete machines, processes or equipment in a very short time. Most imaging systems function much like a video camera. The user can view the thermal emission profile of a wide area simply by looking through the instrument’s optics.

Infrared imaging systems cost between $8,000 for a black and white scanner without storage capability to more than $60,000 for a microprocessor-based, color-imaging system. However, the lower-price units, which only operate in a scanner mode, are not very useful for a long-term PdM program.

Training and applications

Training is critical with the use an imaging system. The variables that can destroy thermal data accuracy and repeatability must be compensated for each time data is acquired. In addition, infrared data interpretation requires extensive training and experience.

Inclusion of thermography into a PdM program will enable you to monitor the thermal efficiency of critical process systems that rely on heat transfer or retention; electrical equipment; and other parameters that will improve both the reliability and efficiency of plant systems. It can also be used to detect problems in a variety of plant systems and equipment, including electrical switchgear, gearboxes, electrical substations, transmissions, circuit breaker panels, motors, building envelopes, bearings, steam lines and process systems that rely on heat retention or transfer.

Safety considerations

Equipment used in infrared thermography inspection is usually energized. For this reason, attention must be given to safety. These safety rules should be followed when performing infrared inspections.

Plant safety rules must be followed.
Because proper use of infrared imaging systems requires the technician to use a viewfinder similar to a video camera to view the machinery to be scanned, he or she is blind to the surrounding environment. Therefore, in addition to the technician, a second safety person is required to ensure safe completion.
Notify area personnel before scanning.
A qualified electrician should be assigned to open and close electrical panels.
When safe and possible, equipment to be scanned should be on line and under normal load with a clear line of sight.
Equipment having interlocked covers without an interlock defect mechanism should be shut down when allowable. If safe, the control covers should be opened and equipment restarted.

When used correctly, thermography is a valuable predictive maintenance and reliability tool. However, benefits derived are directly proportional to how widely it’s used. If it’s limited to annual surveys of roofs or quarterly inspections of electrical systems, the resultant benefits will be limited. When used to monitor critical processes or production systems regularly where surface temperature or temperature distribution indicates reliability or operating conditions, thermography can yield substantial benefits. To gain the maximum benefits from your investment in infrared systems, use it on critical systems that generate capacity in the plant.

Source: R. Keith Mobley, Contributing Editor | Plantservices.com

Predictive Maintenance New Tools

2009-12-13T07:46:00.004+08:00

Learn about condition monitoring beyond oil analysis, temperature and vibration in Sheila Kennedy's monthly Technology Toolbox column.

Getting the most out of installed assets will become more difficult as baby boomers retire. Their unique skillsets and hands-on experience will be hard to replace. One way to minimize this organizational strain is by monitoring the mechanical stress on your machines.

New ultrasonic techniques for condition monitoring make it possible to “hear” friction and stress in rotating machinery, which can predict deterioration earlier than conventional techniques. Condition monitoring, coupled with strategic data integration, help to automate critical processes that influence total plant health.

Ultrasonic condition monitoring: Ultrasonic technology is sensitive to high-frequency sounds that are inaudible to the human ear, and distinguishes them from lower-frequency sounds and mechanical vibration. Machine friction and stress waves produce distinctive sounds in the upper ultrasonic range.
Changes in these friction and stress waves can suggest deteriorating conditions much earlier than technologies such as vibration or oil analysis. With proper ultrasonic measurement and analysis, it’s possible to differentiate normal wear from abnormal wear, physical damage, imbalance conditions and lubrication problems based on a direct relationship between asset and operating conditions.

Among the machine process measurements that can be gauged are speed/rpm, head pressure, weight, and a valve’s position. Ultrasonic sensors that are integrated with condition monitoring software can produce alarms or e-mail notifications when thresholds are exceeded, and trigger maintenance activity.

“The time [remaining] before potential failure can be relatively short,” says Wil Chin, director of field systems for ARC Advisory Group. “With ultrasonics, you can pick up very minute problems manifested by changes in friction, giving maintenance and operations more time to deal with an issue before it shuts down a line or plant.”

Ultrasonic technology also can be used to establish optimal operating parameters, thereby extending asset life. For example, when stress levels are correlated with operating load, it’s possible to identify the rotational speed that generates the least amount of stress on an engine. In a centrifugal pump application, ultrasonic technology can identify cavitation and allow operators to adjust the pump speed and process parameters to reduce detrimental effects on the pump and surrounding equipment.

An additional benefit of ultrasonic technology is the ability to better manage just in time (JIT) inventory. One steel company saved almost $3 million in inventory using a solution from Swantech that provided significant advance warning of possible deterioration within their assets.

Stress wave analysis: “Friction is always present in any machine,” explains Ralph Genesi, president and CEO of Swantech. “Our ultrasonic Stress Wave Analysis (SWAN) technology quantifies this friction and then tracks it as it changes over time with variable loading conditions.”

For example, Swantech’s condition monitoring solution detects minor damage in its earliest stage, and helps to isolate the specific components and location of the components involved. The system calculates the extent of the damage and rate of progression so that maintenance can be scheduled accordingly.

“Swantech is the first to combine ultrasonic sensor technology into a condition monitoring software package,” Chin adds. “The data doesn’t have to be analyzed by a reliability engineer to determine the problem, because the software’s analysis engine recommends the potential cause.”

Integration with maintenance: Condition monitoring systems and smart sensors are becoming increasingly sophisticated, less expensive and more prevalent in the plant environment. User-friendly alternatives are replacing tools that once required specialized skills to operate. Data can now be gathered, analyzed and presented in an actionable format in real time. However, the diversity of condition monitoring methods and devices can impose its own burden.

“Automation suppliers are in the catbird seat, central to all plant information, but without touchpoints to the rest of the equipment or the solution itself,” says Chin. To overcome this issue, automation companies like Invensys and Rockwell Automation are developing or acquiring condition-monitoring technology. “The objective is to compile all data for the operator to view from a single interface – one screen for asset health and another for control.”

To expedite predictive maintenance tasks, condition monitoring suppliers are developing interfaces to enterprise asset management systems so that work orders, inventory requests and associated processes can be activated automatically.

Swantech’s condition monitoring technology is being incorporated into the Invensys Asset Performance Management (APM) solutions under the Invensys name. Integration with Invensys’ Avantis maintenance management software will be available. Swantech is also being integrated with the Indus Asset Suite.

Source: Sheila Kennedy | Plantservices.com

CMMS: Web Based Application for Maintenance

2009-11-19T06:49:00.000+08:00

CMMS is short for Computerized Maintenance Management System. Web based CMMS software programs help public and private organizations manage their maintenance from any location, by logging onto the Internet. Most of them provide features such as work orders, tracking and controlling of inventory, maintenance histories, costs and schedules of maintenance by the hour.

A web based CMMS uses a web browser to access the program. A true web based CMMS system does not require any third party or download program. The program is designed to operate from a central server and the database itself, from another. The more powerful systems require specialized hardware and software to function.

A web based CMMS offers the end user many benefits. Low cost, easy to maintain client and server components, and a user-friendly web browser are the salient features of a web based CMMS. It also offers remote system access with open architecture and interfaces. A very important feature is the web browser itself. They include copy and paste features along with e-mail and help systems. Security and history settings are also available.

A wide array of industries have switched over to using web based CMMS programs. Companies have been able to find new ways to deliver applications across their networks in a more efficient and cost effective manner. Web based CMMS can streamline software delivery and offers a centralized data repository for accessing and analyzing real time data. The cost savings involved are enormous and hence justify the initial investment in the package.

Preventive Maintenance As A Clever Cost-Cutting Process

2009-11-18T06:45:00.000+08:00

So many managers in factories and hotels treat maintenance as a necessary evil. The cost of engineers and technicians, who look after and repair the equipment, is considered a burden that deprives the entity of extra profit. In these entities, one often finds the maintenance personnel, “fighting fires” all the time. They tend to serve those who either stand high in the hierarchy or those who shout the loudest.

The lack of an organised maintenance effort brings about a lot of wasted time, time that is preciously limited and time that costs a lot of money. Studies taken in such workplaces showed that a maintenance technician only spends around 25 per cent of work-time actually on the job solving problems. The rest of the time (75 per cent) is spent looking for spare parts, going to and from the work-site (several times), getting permits to start work and on other similar non-productive work.

Change is always difficult to make and changing operating procedures and mentality even more so. The change required here is to gradually move from reactive maintenance (fighting fires technique) to proactive maintenance (preventing the fires in the first place). Proactive maintenance is more commonly referred to as Preventive Maintenance. This can be achieved through short- and long-term maintenance planning. Employing the help of software improves the chances of success drastically.

A Computerised Maintenance Management System (CMMS) is software dedicated to improving the efficiency, organisation and effectiveness of the maintenance section. A good CMMS is capable of keeping track of repairs done on equipment or machinery, alerts maintenance personnel on when preventive maintenance is due, plans and schedules jobs to personnel who have the skill to do the job in question, makes sure that required parts are ordered in time for maintenance to take place and other similar organising functionalities.

The use of a CMMS can improve maintenance personnel efficiency to 55 per cent or even more. This means that a maintenance person is capable of doing more than twice the amount of work that used to be done before. It often results that as more time is available to the maintenance section, work that used to be outsourced will be handled in-house, further reducing costs, building better in-house skills while affecting maintenance in a shorter time.

A CMMS application also helps reduce the frustration felt by maintenance persons who might feel that the lack of organisation in their department makes them look inefficient in the eyes of their clients. It creates a pride of being professional through planning and efficient handling of maintenance. It improves production, as downtime is reduced. Maintenance can be planned weeks ahead and the necessary arrangements for reassigning production workers to other chores in the factory can be done with ease.

Long-term benefits of using a CMMS is that equipment and machinery lifetime is extended through the proper implementation of preventive maintenance. This in itself reduces the cost of re-investing earned profit into new machines.

Decision taking is also made easier with the data provided by such an application. Data on each and every machine’s repairs and maintenance is recorded. When the question of whether to repair or replace comes up, a more informed decision can be taken.

With all of these benefits, one wonders why so many entities overlook such an application. Reasons vary from the lack of understanding of the benefits such an application provides to the fear that such an application would cost the earth. On the other hand, while it is true that most CMMS software cost too much to be implemented in SMEs, there exist systems aimed at such entity sizes that are more affordable and still offer a good return on investment .

Technology has come a long way and the use for cost cutting and improved bottom line is a clever way towards moving closer to success.

Source: maltabusinessweekly.com | Carmelo Romano

PdM News: R&M Offers HoistMonitor To Improve Efficiency

2009-11-17T18:41:00.001+08:00

R&M Material Handling is now offering HoistMonitor as part of the option list for its RX and QX quick delivery programmes, to improve end-user efficiency.

HoistMonitor is built into a hoist’s electrical panel and supervises and records key data from the hoist. This allows for more efficient planning and scheduling of predictive maintenance, inspections and repairs, R&M said. The data can be accessed directly from the HoistMonitor or from a keypad display in the pendant station when equipped with HoistMonitor Plus.

“Predictive maintenance is a reality for efficient operations on the shop floor,” said a spokesperson for R&M. “Knowing when important maintenance milestones will occur allows you to schedule service during non-working hours.

“Planning hoist repairs and inspections decreases downtime while increasing performance.”

Source: hoistmagazine.com | 16 November 2009

Predictive Maintenance Finally Gets Wide Adoption

2009-11-16T12:43:00.002+08:00

With the need to push costs down, plants are implementing condition-monitoring systems.

At the LyondellBasell Industries oil refinery in Houston, a condition-monitoring program has changed the way the company manages maintenance. Now, instead of gathering readings on paper reports that never get reviewed, plant operators collect data on handheld electronic devices, aggregate the data and track trends that can indicate a problem.

A faulty seal or broken pump can lead to a costly production interruption. “Now, operators have an actual reading from devices,” says Mark Fisher, operations reliability supervisor at LyondellBasell. “If the reading is above a certain limit, they’re prompted to tell their maintenance folks so they can prevent a catastrophic shutdown. The readings allow us to fix things before they break.”

Before implementing a Wonderware IntelaTrac system, the plant took temperature and vibration readings on paper. “You can’t trend on a piece of paper,” says Fisher. “The supervisor would set up a big pile of run sheets in a three-ring binder. By the time anyone got around to looking at them, it was too late to take any action in a timely manner.”

He notes that the paper reporting didn’t include specific data ranges to indicate problems. “With the paper system, one operator would look at the reading and see something wrong, while another operator would see it as OK.” With the handheld data readings, a note will pop up on the screen when the range is exceeded, prompting a call for maintenance. “We lose the inconsistency,” says Fisher.

Big brother?

Fisher notes that there was resistance to the new system initially. “At first, operators were skeptical. They thought it was Big Brother.” That changed when operators started to detect fans that weren’t working and seals that were plugged—problems that had gone undetected with the paper system.

Plants are turning to condition monitoring to reduce costs and replace the knowledge of baby-boomer engineers who are about to retire. Some are implementing predictive tools in-house, while others outsource it to software companies or original equipment manufacturers (OEMs). Many plant operators are just now getting around to implementing condition-monitoring technology that’s existed in their control systems for years. Ease-of-use portals and dashboards are helping resistant workers switch to monitoring technology. Condition monitoring includes a number of analytical tools, including vibration monitoring, oil analysis, temperature monitoring and infrared imaging. They share one thing in common—collecting data on plant equipment and analyzing the data to see when things are out of whack. Sophisticated condition monitoring can also catch subtle aspects of equipment performance. “It may not be the temperature that’s the issue, but that it’s rising quickly,” says Colin Shearer, senior vice president of strategic analytics at SBSS Inc., an analytic software company in Chicago.

For some companies, predictive maintenance has become a boardroom issue. “There are companies that consider condition monitoring a strategic advantage,” says Tom Alford, product manager, integrated condition monitoring at vendor Rockwell Automation Inc, in Milwaukee. “One power-generation company called out condition monitoring in its annual report as part of the company’s strategic vision.”

The recession has encouraged the use of predictive maintenance tools. The tools are becoming more popular as plants struggle to extend the life of their equipment and optimize equipment operation in the midst of a severe downturn. Plants can no longer afford scheduled maintenance—which often means replacing something that’s not broken—or the costly fix-it-when-it-breaks maintenance strategies.

With the pressure to drive down costs, many manufacturers turn to technology they already have on hand but haven’t implemented. “Since we’re having a slowdown in capital projects, they’re starting to use the products that they bought in the past,” says Rich Chmielewski, manager for PCS7 at Siemens Industry Inc., in Alpharetta, Ga. “We’re getting questions about reporting and diagnostics. Our customers are starting to use technology they’ve had but haven’t been using.”

Making Connections

Much of the infrastructure of predictive maintenance systems has been in play for years. Plants already use smart devices that can sense temperature and vibration. They’re also using a fieldbus network that transmits the device data. “You take the data from smart devices and smart control valves, and you send it along the Hart and fieldbus communication and networking systems,” says Stuart Harris, general manager of the Plant Asset Management business at Emerson Process Management, an Austin, Texas, automation supplier. “You take all that data and apply reliability analytics to see the efficiency of the equipment. Then you combine predictive diagnostics with decision support to make the connection with performance.”

One of the biggest hurdles to adopting condition monitoring is getting people to change long-held maintenance practices. “How do you get away from fix-it-when-it’s-broke? A lot of people are stuck in that type of maintenance,” says Emerson’s Harris. “You stop doing some things in routine maintenance that don’t add a lot of value. Then you identify opportunities for bringing in technology that avoids things getting broke.”

The best transition from old-style maintenance to condition monitoring is gradual. “Maintenance is cultural. In many organizations, the effectiveness of maintenance is measured by how quickly they fix machines when they break rather than measuring the overall cost of maintenance,” says Jonathan Hakim, president of Azima DLI, a
condition-monitoring company in Woburn, Mass. “Either that, or it’s measured on ‘Do I perform all my planned maintenance on time?’ To be effective, condition monitoring has to be combined with a move away from planned maintenance.”

Some plants implement monitoring one piece of equipment at a time, so the data collection and analysis in a broad changeover doesn’t stymie the change. “The idea is to give people the right information to collect,” says Jim Frider, manager of mobile solutions at Invensys Operations Management (Wonderware) in Lake Forest, Calif. “You have to know what’s too much data and what’s too little. That helps to get operators on board, which is always challenging.”

Portals, dashboards and benchmarking have helped ease the switchover to predictive maintenance and condition monitoring tools. “Advances in predictive maintenance have less to do with new technology than with new ways to bring the data to the user,” says Bill Polk, research director at AMR Research Inc., in Boston. “It’s how you see the preventive maintenance data that’s important. It’s now aggregated and put into portals.”

Outsourced Monitoring

Some plants turn to equipment OEMs, control vendors or software companies to run their condition monitoring programs. These maintenance monitoring contracts can make predictive maintenance affordable for mid-size to small manufacturers. Some control vendors contract with plants to run their maintenance remotely. A program designed and run by Houston-based vendor ABB Inc. came in handy for Vale Inco’s Voisey’s Bay nickel mine in Labrador, Canada, a site that is more than 150 miles from the nearest road. The Toronto-based company needed to know in advance when a part might fail, because turnaround on spare parts shipments is counted in days, not hours.

To make things more difficult, the mine was a greenfield site, so there was no historical data to indicate acceptable data ranges on the equipment. ABB also had to teach the condition-monitoring program to plant engineers. “That was relatively easy, since it was greenfield,” says Jeff Vasel, global asset optimization manager at ABB. “Change management is easier when you start with people who are new to maintenance.”

ABB monitors the site’s equipment remotely. “I can access their site right now. We monitor heat exchangers, control loops, even the electric flow. We also track vibration and ultrasonics,” says Vasel. “We are able to predict when a pump or motor will fail within 40 hours. Since we can’t get equipment up there quickly, we have to know when the parts will fail so we can have them at the site when it happens.”

The outsourced model has delivered tangible benefits to small and mid-size companies that can’t afford pricy in-house monitoring and analytical systems. “The small manufacturers are getting the same benefits the large end-users are getting,” says Shaun Kneller, account manager at vendor B&R Industrial Automation Corp., in Roswell, Ga. “So the small guys are able to avoid scheduled maintenance. Instead of replacing a bearing every month, they’re replacing it every six months.”

Brain Mapping

The brain drain has also prompted adoption of condition monitoring. The most knowledgeable plant engineers are retiring over the next few years. One way to capture their expertise is to program it into plant technology. “The gray hair brigade is reaching maturity and it’s tough to get new blood in because plants aren’t as sexy as high tech,” says Barry Lynch, a manager with the Proficy Maintenance Gateway at GE Fanuc Intelligent Systems, a Charlottesville, Va., automation supplier. “We’re basically taking the knowledge of the mature workers and pouring it into the IT (information technology) rules. You capture their intellectual property and digitize it.”

As well as digitizing the expertise to keep an individual plant’s equipment running efficiently, the best practices derived from knowledgeable workers can be converted into benchmarks or best practices. “The expertise on how to solve equipment problems lives with a field force of people nearing retirement,” says Brian Anderson, vice president of marketing at Axeda Corp., Foxboro, Mass., which provides remote monitoring services. “You can capture their knowledge and turn it into rules. Then you can use that expertise on a global basis.”

Whether it’s on the control dashboard or outsourced to a vendor, predictive maintenance and control monitoring is seeing widespread adoption in the last couple of years. The economic downturn has prompted tough cost-cutting measures, which means the end of the old and costly “fix-it-when-it-breaks” maintenance mentality. Those who produce predictive maintenance tools have overcome resistance to adoption with easy-to-use dashboards or by taking on the chore themselves.

Source: Rob Spiegel, Contributing Editor | November 2009

Predictive Maintenance Technology Using Fluke Ti25 IR Infrared Thermal Imaging Camera

2009-11-14T14:39:00.001+08:00

The Fluke Ti25 is an industry leading infrared camera system. The Ti 25 is the ultimate tool for troubleshooting, preventive maintenance and predictive maintenance. This thermal Imager is the perfect tool to add to your problem solving arsenal. Built for tough work environments, this high performance, fully radiometric infrared camera is ideal for troubleshooting electrical installations, electro mechanical equipment, process equipment, HVAC/R equipment and others.

Companies use infrared for both predictive maintenance programs and diagnostics tools. Processing manufacturing has many pieces of equipment that can literally cost thousands of dollars every hour of downtime. With infrared companies can predict well in advance any problems that may be on the horizon. The return on investment for an infrared program is usually meet after only a few detections of potential problems.

The Fluke Ti25 features Fluke's patented IR fusion capabilities. IR fusion allows the user to blend both the infrared and visual light image. IR fusion ability allows the user to diagnose problems more effectively and efficiently. Other features include; a thermal sensitivity of just 100mk, 160x120 resolution, instant high low spot meters, sixty second voice annotation, seven different color palettes, a six hundred and ninety two degree temperature range, an industry leading two year warranty, and Smart View 2.1 software with all future upgrades of the software for free. This is all backed by Fluke's award winning customer service and un matched product durability.

Recently the Fluke Ti25 recently won an award from Plant Engineering magazine for product of the year. Different manufactures entered several different models, and the Ti25 took the award.

Equipment Maintenance Management Software

2009-10-26T20:48:00.000+08:00

The strategic goal of any production and utilities department is to maximize production. Machinery and equipment is run continuously, or in batches. The equipment can be complex, as in nuclear reactors, or as simple as lathe machines. The goal to maximize production is determined by the availability of the equipment and its condition.

The strategic goal of the maintenance department servicing production and utilities departments is to ensure the reliability and availability of the machines. The operational goals of the maintenance department require availability and scheduling of employees for work orders, maintaining inventories for the parts, and the analysis of maintenance-related problems.

Equipment maintenance management software helps achieve the strategic and operational goals of a maintenance organization. These software packages are available as stand-alone applications customized for specific requirements, or integrated end-to-end solutions.

At the strategic level, equipment MMS helps top management to make decisions about the purchase of equipment by providing data and analysis of the cost of managing the assets, and by providing data about the vendor and analysis of the equipment provided by various vendors.

At the operations level, equipment MMS helps manage the maintenance schedule of the equipment. The software helps in the preventive and predictive maintenance by analyzing the historic data of the previous maintenance work orders. It also helps decide the availability of the equipment and the duration of the work. An integrated solution helps in optimizing the inventories by determining the parts usage and reorder time.

Equipment MMS is ideally suited for small and medium-sized enterprises for which the entire integrated solutions may be very expensive. The decision to install equipment MMS should be guided by the requirements of the organizations and the features of the software.

Develop Good Strategies For Effective Preventive Maintenance (2/2)

2009-10-26T10:06:00.001+08:00

A second and more dominant area of confusion occurs when a scheduled task reveals unacceptable equipment deterioration (like the problem above in the MO situation, except it was not unexpected since a PM task discovered its presence). So actions are taken to repair/restore the full functionality before an unexpected operational impact can occur. Is the repair/restore action preventive or corrective?

If you will recall that the purpose of the PM task is to perform actions that will retain functional capabilities, then the answer is essentially self evident — the repair/restore action is preventive. Why? Because a proper structuring of the PM task will always include not only the search for equipment condition, but also the requirement to do something about it if the search uncovers a problem.

This search includes PM tasks that require inspection, monitoring parameters that detect failure onset, discovery of hidden failures and even restoration of equipment that was deliberately allowed to run to failure. Unfortunately, though, many CMMS programs will not allow the user to create or code a new work order to cover the emergent work as PM. This additional PM work can only be coded as CM. This inflates the cost of CM, and can lead management to question why CM costs are increasing even when their PM program had been recently improved.

As a general rule, corrective maintenance is more costly than preventive maintenance. If anyone should doubt this, then just compare two similar plants or systems where one has a proactive maintenance program and the other a reactive maintenance program. Which one do you think has the lower overall maintenance cost and higher availability?
Why do preventive maintenance?

For the past 15 years, as part of our seminars and client training programs, we frequently ask the question "Why do preventive maintenance?" The answers that we consistently hear reflect the popular belief that PM is done for a rather narrowly defined reason and this, as such, leads to the exclusion of a number of golden opportunities for PM enhancement.

So why do you do preventive maintenance? The overwhelming majority of maintenance and plant engineering personnel will respond "To prevent equipment failures." Would that have been your response? If so, you are correct — but not complete in your viewpoint. Unfortunately, we are not yet smart enough to prevent all equipment failures. But that does not mean that our ability to perform meaningful preventive maintenance tasks must end there.

In fact, there are three additional and important options to consider. First, while we may not know how to prevent a failure, frequently we do know how to detect the onset of failure. And our knowledge of how to do this is increasing every day, and is creating a whole new discipline called predictive maintenance. Second, even though we may not be able to prevent or detect the onset of failure, we often can check to see if a failure has occurred before equipment is called into service. Various standby and special purpose equipments (whose operational state is often hidden from the operator's view until it is too late) are candidates for this area. Thus, discovery of hidden failures is yet another PM option available to us.

There are also situations in a well planned PM program where economics and/or technical limitations can dictate a decision to do nothing — he appropriately labeled Run-To-Failure (RTF) option. This RTF option is not to be confused with the more general situation of missing potentially useful PM actions due to oversight or lack of attention to PM planning.

To summarize, there are four basic factors behind the decisions to define and choose preventive maintenance actions:
1. Prevent (or mitigate) failure occurrence.
2. Detect onset of failure.
3. Discover a hidden failure.
4. Do nothing, because of valid limitations.

Source: Anthony M. Smith and Glenn R. Hinchcliffe (Plant Engineering - November 1, 2005)

Develop Good Strategies For Effective Preventive Maintenance (1/2)

2009-10-26T08:25:00.000+08:00

Experience has clearly shown that some confusion does exist over just what people mean when they use the term preventive maintenance. One significant factor stems from the evidence that a vast majority of our industrial plants and facilities have been operating for extended periods, years in many cases, in a reactive maintenance mode. That is to say that the maintenance resources have been almost totally committed to responding to unexpected equipment failures. Corrective, not preventive, maintenance is frequently the operational mode of the day, and this tends to blur what is preventive and what is corrective.

In one actual extreme case, a plant developed an entire culture that fostered a feeling of pride in people's ability to fix things rapidly and under pressure when a forced outage occurred. Plant personnel viewed their actions as preventive in the sense that they were able to "prevent" a long outage because of their highly efficient and effective reactive and corrective actions. What the plant staff did not consciously recognize (or acknowledge) was that they were the highest cost per unit producer among their peers.
We use the following definition of preventive maintenance (PM):

Preventive maintenance is the performance of inspection and/or servicing tasks that have been preplanned (i.e., scheduled) for accomplishment at specific points in time to retain the functional capabilities of operating equipment or systems.

The word "preplanned" is the key element in developing a proactive maintenance mode and culture. In fact, this now provides us with a very clear and concise way to define corrective maintenance (CM):

Corrective maintenance is the performance of unplanned (i.e., unexpected) maintenance tasks to restore the functional capabilities of failed or malfunctioning equipment or systems.As viewed by the authors, the entire world of maintenance activity is fully encompassed in these two definitions.

However, there are two troubling factors that people frequently question which give rise to some of the confusions over the "PM or CM" discussions. The first of these involves the games that people play with the terminology. These games can be driven by such diverse nontechnical factors as accounting practices or political (regulatory) pressures. For example, some plants, in addition to planned outages and forced outages, have a third category known as a maintenance outage (MO).

The MO occurs as a result of an unexpected equipment problem which hasn't quite yet reached the full failure state but will do so very soon. So the plant management will delay the shutdown until some off-peak period when the plant outage is more tolerable, and hope that the equipment will hold out until then.

Now from an operational point of view, this is a very smart thing to do — but, as a rule, MOs are not counted when it comes to reporting the plant forced outage rate. Somehow they seem to wind up in the preplanned category ("after all, we planned to fix it next Saturday!"). Make no mistake about it, an MO is a forced outage and should be labeled as such when measurements are made. You are only kidding yourself to do otherwise.

Please also read:
Develop Good Strategies For Effective Preventive Maintenance (2/2)

Source: Anthony M. Smith and Glenn R. Hinchcliffe (Plant Engineering - November 1, 2005)

SKF Machine Condition Advisor (MCA)

2009-10-25T22:54:00.001+08:00

Machine monitoring, made simple.

The SKF Machine Condition Advisor is a rugged, easy-to-use, hand held device that simultaneously measures vibration signals and temperature to indicate machine health and bearing damage - providing early warning of machine problems before a costly breakdown occurs.

Essential plant equipment such as pumps, fans, motors, compressors, gear boxes, cranes and conveyors rely on bearings to keep machines running.

Using the SKF Machine Condition Advisor to measure both the machine condition and bearing activity for changes in vibration and temperature, operations or maintenance staff can detect a pending machine failure before it results in lost production, unplanned downtime and machine damage.

Features
* Quick and easy to set up and use
* Compact, durable and ergonomically designed
* Automatically compares measurements to established standards
* Alert and Danger prompts provide diagnostic confidence
* Efficient, economical and environmentally friendly

Benefits
* Avoid costly failures
* Plan maintenance
* Reduce maintenance costs
* Improve machine reliability
* Ideal for both expert and novice users

Solutions 2.0 Conference Reliability & Operations Solutions supporting Organizational Performance

2009-10-25T22:30:00.000+08:00

Featuring:
IMC-2009 24^th International Maintenance Conference (more)
OPS-2009 Operations Performance Summit (more)
PdM-2009 Predictive Maintenance Technology Conference (more)
LubricationWorld (more)
Ocean Walk Village Hilton
Daytona Beach Florida, USA
November 17-19, 2009 (Bonus activities on November 16)

Four Task Categories To Understand In Undertaking Preventive Maintenance (4/4)

2009-10-13T13:02:00.000+08:00

Run-To-Failure (RTF)

As the name implies, we make a deliberate decision to allow an equipment to operate until it fails — and the maintenance action occurs only after the failure has occurred. There are some limited cases where such a strategy makes common sense:

1. We can find no PM task that will do any good irrespective of how much money we might be able to spend.

2. The potential PM task that is available is too expensive. It is less costly to fix it when it fails, and there is no safety impact at issue in the RTF decision.

3. The equipment failure, should it occur, is too low on the priority list to warrant attention within the allocated PM budget.

4. Note the distinction between FF and RTF. With FF the failure is hidden and we do not want to be surprised by its occurrence if the failure should happen. With RTF, we have made a deliberate decision not to be concerned about failure occurrence, be it evident or hidden, and will simply correct the failure at our time of choosing should it occur.

Four Task Categories To Understand In Undertaking Preventive Maintenance (3/4)

2009-10-13T12:58:00.001+08:00

Condition-Directed (CD)

When we do not know how to directly prevent or retard equipment failure-or it is impossible to do so — the next best thing that we can hope to do is to detect its onset and predict the point in time where failure is likely to occur in the future. We do this by measuring some parameter over time where it has been established that the parameter correlates with incipient failure conditions. When such is done, we call it a condition-directed or CD task. Thus, a CD task would pre-warn us to take action to avoid the full failure event. If the warning comes soon enough, our action can most likely be taken at some favorable timing of our choice.

The CD task, like the TD task, has a periodicity for the measurements, but actual preventive actions are not taken until the incipient failure signal is given. The CD task takes two forms: (1) we can measure a performance parameter directly (e.g., temperature, thickness) and correlate its change over time with failure onset; or (2) we can use external or ancillary means to measure equipment status for the same purpose (e.g., oil analysis or vibration monitoring). With the CD task, all such measurements are nonintrusive. The keys to classifying a task as CD are: (1) we can identify a measurable parameter that correlates with failure onset; (2) we can also specify a value of that parameter when action may be taken before full failure occurs; and (3) the task action is nonintrusive with respect to the equipment.

Failure-Finding (FF)

In large complex systems and facilities, there are almost always several equipment items-or possibly a whole subsystem or system-that could experience failure and, in the normal course of operation, no one would know that such failure has occurred. We call this situation a hidden failure. Backup systems, emergency systems, and infrequently used equipment constitute the major source of potential hidden failures. Clearly, hidden failures are an undesirable situation since they may lead to operational surprises and could then possibly initiate an accident scenario via human error responses. For example, an operator may go to activate a backup system or some dormant function only to find that it is not available and, in the pressure of the moment, fail to take the correct follow-up procedure. So, if we can, we find it most beneficial to exercise a prescheduled option to check and see if all is in proper working order. We call such an option a failure-finding task.

Let's look at a simple example-the spare tire in our automobile. If you are like us, you don't really worry about a flat spare tire because you have AAA coverage, and are never more than 10 to 15 minutes away from an ability to get emergency road service-except for that once-a-year trip with the family into "uncharted lands" (e.g., Death Valley). Again, if you are like us, you do check the spare before you leave — and that is a failure-finding task.

Notice that the only intent in such an action is to determine if the spare tire is in working order or not. We are doing nothing to prevent or retard a flat tire (a TD task) or to measure its incipient failure condition (a CD task). It is or is not in working order. And, if it is not in working order, we fix it. That is the essence of what a failure finding task is all about. (Is it OK? If not, fix it.)

Four Task Categories To Understand In Undertaking Preventive Maintenance (2/4)

2009-10-13T12:50:00.000+08:00

This is part 2 of the series Four Task Categories To Understand In Undertaking Preventive Maintenance

Time Directed (TD)
In the not too distant past, virtually all preventive maintenance was premised on the basis that equipment could be periodically restored to like-new condition before it was necessary to discard it for a new (or improved) item. This premise thus dictated that equipment overhauls were about the only way to do preventive maintenance.

Today, we are slowly realizing that this is not always the correct path to pursue. However, in many valid situations we still specify PM tasks at predetermined ("hard time") intervals with the objective of directly preventing or retarding a failure. When such is done, we call it a time-directed task. A TD task is still basically an overhaul action-sometimes very complete, extensive, and expensive (like rebuilding an electric motor), and sometimes very simple and cheap (like alignments and oil/filter replacements). As a rule of thumb, whenever we have a planned intrusion into the equipment (even just to inspect it), we have in essence an overhaul-type action which is labelled a TDI (Time-Directed Intrusive) task. Some time-directed tasks can be non-intrusive, such as simple visual inspections or minor adjustments that do not require a breach of the equipment boundary or housing. In this case, the action is simply labelled as a TD task.

More often than not, time-directed tasks tend to be intrusive. A simple example that everyone can picture is the changing of oil in our automobile. Here, we intrude in the PM action by removing the drain plug (which will leak if not properly reinstalled), by injecting fresh oil (which must be of the correct type, grade, and quantity with the fill cap properly replaced), and by replacing the oil filter (which will leak if the gasket is not properly installed). The "hard time" associated with this action is car mileage, which has been suggested by the manufacturer who has collected years of experience defining excessive engine wear as a function of oil deterioration due to contaminants and loss of viscosity.

Notice that this simple PM task, a TDI task, presents several opportunities for human error to creep into the procedure. The keys to categorizing a task as time-directed are:

(1) the task action and its periodicity are preset and will occur without any further input when the preset time occurs;

(2) the action is known to directly provide failure prevention or retardation benefits; and

(3) the task usually requires some form of intrusion into the equipment.

Four Task Categories To Understand In Undertaking Preventive Maintenance (1/4)

2009-10-13T12:43:00.002+08:00

By Mac Smith and Glenn HinchcliffePlant Engineering - December 1, 2005

There are four basic factors behind the decision to define and choose preventative maintenance actions:
1. Prevent or mitigate failure occurrence
2. Detect onset of failure
3. Discover a hidden failure
4. No nothing, because of value limitations

By identifying the four factors for doing preventive maintenance, we have also set the stage for defining the four task categories from which a PM action may be specified. These task categories, by one name or another, are universally employed in constructing a PM program, irrespective of the methodology that is used to decide what PM should be done in the program.

The four task categories are as follows:
1. Time-directed (TD): aimed directly at failure prevention or retardation.
2. Condition-directed (CD): aimed at detecting the onset of a failure or failure symptom.
3. Failure-finding (FF): aimed at discovering a hidden failure before an operational demand.
4. Run-to-failure (RTF): a deliberate decision to run to failure because the others are not possible or the economics are less favorable.

Is Preventive Maintenance Necessary?

2009-10-08T08:01:00.002+08:00

Written by William C. Worsham (Senior Consultant and Trainer, Reliability Center, Inc.) Feature article for "Focus on Reliability" Column at MaintenanceResources.com

Reliability Centered Maintenance has changed the way we think about Preventive Maintenance (PM). It has caused some to question whether it is even necessary to do preventive maintenance. The truth is most manufacturing facilities would benefit from a good preventive maintenance program. It would be especially beneficial for those plants that rely on breakdown or run-to-failure maintenance. But, a preventive maintenance program is potentially risky, so it must be administered and performed properly to be successful. This paper will examine both the benefits and risks of preventive maintenance and offer some ideas on how to make it successful. We will start with a definition of preventive maintenance.

What is Preventive Maintenance?

Preventive maintenance is planned maintenance of plant and equipment that is designed to improve equipment life and avoid any unplanned maintenance activity. PM includes painting, lubrication, cleaning, adjusting, and minor component replacement to extend the life of equipment and facilities. Its purpose is to minimize breakdowns and excessive depreciation. Neither equipment nor facilities should be allowed to go to the breaking point. In its simplest form, preventive maintenance can be compared to the service schedule for an automobile.

A bona fide preventive maintenance program should include:

Non-destructive testing
Periodic inspection
Preplanned maintenance activities
Maintenance to correct deficiencies found through testing or inspections.

The amount of preventive maintenance needed at a facility varies greatly. It can range from a walk through inspection of facilities and equipment noting deficiencies for later correction up to computers that actually shut down equipment after a certain number of hours or a certain number of units produced, etc.

Many reasons exist for establishing a PM program. Listed below are a few of these. Whenever any of these reasons are present, a PM program is likely needed.

Reasons for Preventive Maintenance

Increased Automation
Business loss due to production delays
Reduction of insurance inventories
Production of a higher quality product
Just-in-time manufacturing
Reduction in equipment redundancies
Cell dependencies
Minimize energy consumption (5% less)
Need for a more organized, planned environment

Why Have a PM Program

The most important reason for a PM program is reduced costs as seen in these many ways:
Reduced production downtime, resulting in fewer machine breakdowns.
Better conservation of assets and increased life expectancy of assets, thereby eliminating premature replacement of machinery and equipment.
Reduced overtime costs and more economical use of maintenance workers due to working on a scheduled basis instead of a crash basis to repair breakdowns.
Timely, routine repairs circumvent fewer large-scale repairs.
Reduced cost of repairs by reducing secondary failures. When parts fail in service, they usually damage other parts.
Reduced product rejects, rework, and scrap due to better overall equipment condition.
Identification of equipment with excessive maintenance costs, indicating the need for corrective maintenance, operator training, or replacement of obsolete equipment.
Improved safety and quality conditions.

If it cannot be shown that a preventive maintenance program will reduce costs, there is probably no good reason other than safety to have a PM program.

The Law of PM Programs:
There are many advantages for having a good preventive maintenance program. The advantages apply to every kind and size of plant. The law of PM programs is that the higher the value of plant assets and equipment per square foot of plant, the greater will be the return on a PM program. For instance, downtime in an automobile plant assembly line at one time cost $10,000 per minute. Relating this to lost production time an automobile manufacturer reported that the establishment of a PM program in their 16 assembly plants reduced downtime from 300 hours per year to 25 hours per year. With results such as this no well-managed plant can afford not to develop a PM program.

Preventive Maintenance Program Risks
As mentioned in the beginning of this report, preventive maintenance does involve risk. The risk here refers to the potential for creating defects of various types while performing the PM task. In other words, human errors committed during the PM task and infant mortality of newly installed components eventually lead to additional failures of the equipment on which the PM was performed. Frequently, these failures occur very soon after the PM is performed. Typically, the following errors or damage occur during PM’s and other types of maintenance outages.

Damage to an adjacent equipment during a PM task.
Damage to the equipment receiving the PM task to include such things as:
Damage during the performance of an inspection, repair, adjustment, or installation of a replacement part.
Installing material that is defective, incorrectly installing a replacement part, or incorrectly reassembling material.
Reintroducing infant mortality by installing new parts or materials.
Damage due to an error in reinstalling equipment into its original location.

Especially disturbing about these types of errors is the fact that they go unnoticed – until they cause an unplanned shutdown. There is some published data that illustrates this point. It comes from the fossil-fuel power industry.

A review of the data from fossil-fueled power plants that examined the frequency and duration of forced outages after a planned or forced maintenance outage reinforces this concept. That data showed that of 3146 maintenance outages, 1772 of them occurred in less than one week after a maintenance outage. Clearly, this is pretty strong evidence that suggests that in 56% of the cases, unplanned maintenance outages were caused by errors committed during a recent maintenance outage.

Having performed and supervised many industrial PM’s, I also support this concept. I can remember many instances where it would take days after a PM was performed to get everything back to normal. This was particularly true when many components that came in contact with the product being produced were replaced. I remember working with the quality people on many occasions to insure that every position on a multiple position machine was once again producing first quality product. Many times it required adjusting and/or replacing components that were adjusted or replaced on the PM.

How to Have a Successful PM Program
The key to a successful Preventive Maintenance (PM) program is scheduling and execution. Scheduling should be automated to the maximum extent possible. Priority should be given to preventive maintenance and a very aggressive program to monitor the schedule and ensure that the work is completed according to schedule should be in place.

Preventive Maintenance Execution:
Traditional preventive maintenance was based on the concept of the bathtub curve. That is, new parts went through three stages, an infant mortality stage, a fairly long run stage, and a wear-out stage. The PM concept was to replace these parts before they entered the wear-out phase. Unfortunately, Reliability Centered Maintenance based on research done by United Airlines and the rest of the aircraft industry showed that very few non-structural components exhibit bathtub curve characteristics. Their research showed that only about 11% of all components exhibit wear-out characteristics, but 72% of components do exhibit infant mortality characteristics. These same characteristics have been shown to apply in Department of Defense systems as well as power plant systems. It is very likely that they apply universally as well. Therefore, they should be taken into account when configuring preventive maintenance on industrial equipment.

In order to have a successful PM program, the message is clear. The PM should focus on cleaning, lubrication, and correcting deficiencies found through testing and inspections. When there is a need to adjust or replace components, it should be done by highly trained and motivated professionals. Predetermined parts replacement should be minimal and done only where statistical evidence clearly indicates wear-out characteristics. In the absence of data to support component replacement, an age exploration program or the collection of data for statistical analysis to determine when to replace components should be initiated. Borrowing from the Japanese, lubrication points should be clearly marked with bright red circles to ensure that lubrication tasks are not missed. Cleaning should be carried our to remove dust, dirt, and grime because these things mask defects that can cause unplanned maintenance outages.

Motivating Preventive Maintenance Workers:
A quality preventive maintenance program requires a highly motivated preventive maintenance crew. To provide proper motivation, the following activities are suggested:

Establish inspection and preventive maintenance as a recognized, important part of the overall maintenance program.
Assign competent, responsible people to the preventive maintenance program.
Follow-up to assure quality performance and to show everyone that management does care.
Provide training in precision maintenance practices and training in the right techniques and procedures for preventive maintenance on specific equipment.
Set high standards.
Publicize reduced costs with improved up-time and revenues, which are the result of effective preventive maintenance.

In addition to explaining the importance of a good preventive maintenance program and the benefits that can be derived from it, training is probably the most effective motivational tool available to the maintenance supervisor. Maintenance and training professionals have estimated that a company should spend $1200 per year for training of supervisors and $1000 per year for each craftsperson. In fact, due to advances in technology, if the company has not provided any training for craftspeople in the past 18 months, their skills have become dated.

Conclusion
It is possible to have a successful preventive maintenance program. From a cost reduction viewpoint it is essential, but it does entail risk. When the proper care is taken, the risks, however, can be minimized. In order to minimize risk, preventive maintenance has to be carefully planned and carried out by well-trained and motivated workers. The biggest benefits of a PM program occur through painting, lubrication, cleaning and adjusting, and minor component replacement to extend the life of equipment and facilities.

Preventive Maintenance: Replacing Incandescent Lamps with LEDS

2009-10-05T13:10:00.003+08:00

Currently, there is interest in high efficiency, long-life, light emitting diode (LED) lamps for use in factories, institutional, and commercial applications, because the costs of electricity for lighting and labor for bulb replacement are significant. The goal of the LED manufacturers is to build a very high-brightness white LED that is economical and efficient enough to be used for illumination. To gain widespread acceptance as a legitimate light source for general lighting, LEDs must be able to economically and reliably deliver illumination levels of white light of a quality within today's acceptable standards.

Theory of operation

An LED is a PN junction semiconductor that emits photons when forward biased. The emission of light occurs when minority carriers recombine with carriers of the opposite type in the band gap of the diode. The wavelength of the emitted light — which determines its color — varies according to the semiconductor material.

LEDs are processed in wafer form similar to silicon integrated circuits, and broken out into dice. The simplest packaged LED is the indicator lamp. Typically, LEDs have a mean time between failures (MTBF) of more than 100,000 hr.

Today's ultrabright LEDs exceed the light output of incandescent and halogen lamps. They don't have the maintenance requirements associated with filament lamps. LEDs can be dimmed using a pulse-width modulation (PWM) circuit, which delivers energy in pulses of varying duty cycle.

History of LEDs

The first reports of a device with properties similar to LEDs dates back to 1906 when Henry Round reported electroluminescence while experimenting with carborundum. However, LEDs didn't become commercially available until the early 1960s. Texas Instruments sold an infrared (IR) device for $130 and GE distributed red LEDs through the Allied Radio catalog for $260. They were expensive and sold in low volumes.

IBM used LEDs as on-off indicator lights on circuit boards in a mainframe computer constructed around 1964, which marks the first time LEDs were used to replace incandescent lamps. LEDs used less power, could be mounted directly on the circuit board, and had a much longer life expectancy, which made using LEDs attractive from a maintenance perspective.

In the mid 1980s, the U.S. military began gradually replacing tungsten filament indicators with LEDs, and they began appearing in elevator cars. As with the IBM application, LEDs were designed into pieces of equipment. They were mounted on printed circuit boards (PCBs), mounted in equipment panels and face plates using specific mounting bezels with wires soldered to their leads, and plugged into sockets made specifically for LEDs.

LED performance made a leap in the early 2000s. Companies started manufacturing flashlights using LEDs instead of the traditional incandescent bulb. As improvements were made in brightness and color, LEDs moved farther into tungsten territory. They appeared in traffic signals, home entertainment, and decorative lighting.

Today, LEDs are used in many industries from automotive to architectural lighting applications. Industrial plants are discovering the benefits of replacing traditional bulbs with LED lamps. For example, hundreds of incandescent lamp part numbers now have direct LED-based replacements. Most LED suppliers have extensive cross-reference literature and databases. Standard lamp bases are available, allowing LED lamps to replace incandescent lamps without having to retrofit equipment.

Flashlights continue to get brighter. Some currently available flashlights suitable for industrial use boast as much as 1800 foot-candles (fc) of white light. LED floodlights, work lights, and luminaires for general-purpose lighting applications are available as well.

Benefits

LEDs have enjoyed continued success because they use considerably less power and last much longer than tungsten filament incandescent bulbs. LED lamps use only 10% to 20% of the energy consumed by equivalent incandescent lamps. An average LED life span can exceed 100,000 hr — more than 11 yr.

LEDs are solid-state devices, which make them virtually immune to electrical and mechanical shock — unlike incandescent lamps, which have filaments that are very susceptible to electrical and mechanical shock. Electrical shock comes from constant on-off transitions, transients, and surges; mechanical shock comes from bumping, jarring, and other forms of vibration. Also, LEDs produce very little heat, making them an attractive alternative to incandescent lamps in applications where heat is an issue, such as biotechnology, chemical, and food processing.

Issues

LEDs had to overcome physical and technological issues to get where they are today. The primary hurdles have been drive current, packaging, color, and price. Although these issues have been addressed, they still exist to some degree. Drive current directly affects LED lamp output and lamp life. LEDs are inherently robust. They are capable of delivering high output at high current, as long as heat is extracted properly.

Packaging issues include thermal management, current handling capability, and color. Advanced device packaging allows adequate heat dissipation and increased current capacity. Packaging also affects color, which is extremely important in applications that require white light. Use of LEDs as illumination sources requires white light with a degree of "warmth." This requirement must be met if LEDs are to make any headway in replacing incandescent lamps for general-purpose illumination. Fluorescent lighting addressed this issue. And it appears that LEDs are rising to meet the challenge as well.

The cost-effectiveness of LEDs depends on the application. Today, the system price is high for replacing conventional incandescent lamps with LED-based technology. However, for established LED applications, such as control panel indicators and annunciator lamps, LEDs are more cost effective. Although the unit price is higher, the lower power consumption and longer lamp life help offset the initial purchase price. Some plants can justify the higher cost of LEDs for this application based on lower maintenance costs alone.

Source: Plant Engineering Magazine - January 1, 2005

An Introduction To Maintenance Management Software

2009-10-05T08:51:00.000+08:00

Maintenance management software is a complete maintenance solution for businesses and organizations to improve their efficiency. It helps to achieve optimum utilization of vehicles, equipments, and other facilities at the company’s disposal. The functions of a maintenance management software include asset management, inventory ordering, work order generation and management, tracking and reporting, purchasing management, scheduling, service request processing, preventive maintenance, predictive maintenance, and much more.

Maintenance management software is a perfect tool for all types of businesses including manufacturing plants, health care facilities, retail and commercial properties, government firms, and educational institutions. Standard maintenance management software provides effective scheduling of work and generates full history reports. It estimates costs correctly, handles spare parts inventory, improves the reordering system, and enhances the material tracking process. It can keep track of service contracts, problem reports, preventive maintenance schedules, and material inventories. Maintenance management software can reduce paperwork and communication costs. In short, maintenance management software helps to improve the productivity of any business.

Most maintenance management software has facilities for detailed and graphical reports. Most software provides easy report writing tools that do not require any knowledge of programming. Many maintenance management software programs help to automate tracking and scheduling of maintenance activities. Some maintenance software has advanced purpose-built user interface and browser-based requesting system. Built-in procedure libraries are part of most common maintenance management software. A lot of software comes with comprehensive dispatching and scheduling tools that help enhance productivity. Certain software allow you to stay connected with customers, suppliers, technicians, and the back office with a view to achieve best results.

Most maintenance management software are user-friendly and require no training. MPulse, ePAC, Servicom, CrossForm, Smart Maintenance, MainBoss CMMS, FTMaintenance, and FaciliWorks are among the popular maintenance management software available in the market.

Preventative Maintenance Software

2009-10-04T16:00:00.000+08:00

Preventive maintenance software is a program that helps you reduce daily workload and do your department’s job more efficiently. A preventive maintenance software system deals with the various aspects of a maintenance operation such as scheduling employees and work orders, inventory control, purchasing, breakdown maintenance, corrective maintenance and project work. It allows users to recognize and fix possible problems and errors in a system. The preventive maintenance software reduces a company’s workload by managing all the routine operations of the maintenance department.

Preventive maintenance software keeps exact maintenance records for industries that have reliability analysis and validation requirements. It provides information that can be used for cost estimates, cost reduction, budgeting, and cost control. Also, preventive maintenance software identifies high cost areas on procedures and equipments. Standard preventive maintenance management software offers full history records for all maintenance work. It lists and tracks outside customers and vendors and displays information on specific work orders.

Some preventive maintenance software automatically schedule preventive maintenance for up to a year and beyond. Weekend days and holidays can be skipped or included. Equipment tracking is a major function of most preventive maintenance software. The software enters and tracks equipments by name, class, category, and serial number. Preventive maintenance software produces reports on complete equipment preventive maintenance history with detailed information on who did the work and when.

Generally, preventive maintenance software can produce a work order for each piece of preventive maintenance to be done. The work order usually contains step-by-step instructions on how to execute a particular preventative maintenance job. The required machinery and materials are also listed. A full inventory control and tracking is a must for preventive maintenance software. Most maintenance software come with a flexible full inventory control module. When inventory levels run low, the software alerts the operator to reorder.

Source: ezinearticles.com

Preventive and Predictive Maintenance

2009-10-03T20:03:00.000+08:00

by Ken Staller, Senior Maintenance Consultant

If you ask ten people what their definition of Preventive Maintenance is, you will get ten different answers. The tasks range from very simple to fairly complex. What's more, the manner in which they are performed and the depths to which they are carried out vary considerably. For the purpose of this guide to Preventive Maintenance (PM) and Predictive Maintenance (PDM), I will use the following definition: PM and PDM are a series of tasks and company policies that, if followed, improve and keep business profits as high as possible. This is achieved by adhering to three general guidelines.

Maintain the production equipment and plant utility systems equipment as close to brand new condition as possible and have all equipment ready to start up and run with no unplanned shutdowns.
Maintain the production equipment and plant utility systems equipment in the best possible operating condition for the purpose of producing quality manufactured goods while the machines are in service.
Complete all PM and PDM work on a regularly scheduled basis without exceeding the "Point of Diminishing Returns on Investment" for the labor, tools and materials required to perform the work.

The difference between Preventive and Predictive Maintenance is that Preventive Maintenance tasks are completed when the machines are shut down and Predictive Maintenance activities are carried out as the machines are running in their normal production modes.

With PM and PDM systems – as in all systems and processes of work – there are the Who, What, When, Where and Why questions to answer before any actual work begins. With the above three guidelines we have already defined the "Why" question.

The "Who" question relates to several different types of members of the PM and PDM team.

Someone who has an abundance of maintenance and plant engineering experience should write the individual tasks. To receive the expected results from the investments made in the PM and PDM protocol, the person writing the details of what needs to be done must have a deep understanding of the many aspects of machines. Aging, wear, component material fatigue patterns, effects of dirt and other contaminants, heat/cold, humidity, effects of chemical contact, vibration, lubrication practices, measurement processes, maximum safety methods, work efficiency standards, work scheduling, people skills, and plant processes are all factors that must be carefully considered.
The mechanics and electricians that perform the PM and PDM work must be of high caliber and possess the skill levels of a maintenance department. On average, 85% to 90% of PM and PDM work orders call for machine inspection work and only 10% to15% lubrication work. The people performing these tasks must fully understand machine and machine component operations before they can effectively inspect for specific problems and negative operating trends.
The management person directly responsible for the people performing the PM and PDM work must understand the work to be accomplished and set the performance standards, goals and expectations. They must be able to monitor the quality and quantity of work completed as well as measure the results. Also, they should be able to make on going changes and improvements to the individual PM tasks as part of an overall continuous improvement effort. These changes are dictated by the results of measurements and changes in the plant processes and equipment. Finally, the management person should also be able to complete component failure analyses. Determining why and how a component failed is the first step in determining how to prevent subsequent failure.
The plant upper management must view the PM and PDM work system as required constant work practices that are just as important to the production process as any other function. This will require a minimal planned downtime of equipment to accomplish all PM and PDM work.
Production employees also are a significant part of PM systems. They can be, and many times are, the first to see changes in the equipment they operate. Total Productive Maintenance (TPM) represents the active participation of all production employees in various machine set-ups, inspections and, in some cases, the lubrications of machinery. The amount of participation in TPM varies with the complexity of the equipment, the types of processes involved and the overall skill levels of the work force. Training the work force and the setting its expectations varies with the philosophies of the plant management of each facility.
Contractors should be included in some PM work, especially the PDM work involved. Many contractors can supply cost effective services in some of the more specialized inspections and tests required. For example, many plants do not have trained refrigeration mechanics and they hire contractors to do the scheduled PM on Heating Ventilation and Air Conditioning (HVAC) units for the plant systems. Other contractor applications may be for air compressor and air dryer PM. In addition, vibration and ultra sonic analyzing is highly specialized aspect of PDM and requires extensive training and high test equipment purchase and upkeep costs.

The "What" and "Where" of PM consists of what equipment is to be inspected and lubricated and to what extent and detail the work is to be performed. Typically detailed PM and PDM procedures are written for all production equipment to insure that all machine components are inspected and lubed for maximum sustained operation. This process should also be applied to other plant equipment systems, such as machines that supply the plant utilities including air compressors, air dryers, boilers, electrical sub-stations, motor control centers, and wastewater treatment. Plant safety systems also should be included, including natural and propane gas systems, tanks, fire alarms and suppression systems, emergency lighting, overhead cranes and hoists, and ceiling mounted items such as lights, fans, and piping. Many plants also choose to include PM work on HVAC systems, overhead door and dock plates, forklifts, company vehicles, truck fleets, roof leak detection, air emissions and other systems usually not considered until there is a problem.

The detail and extent of the PM and PDM work varies with the type of equipment involved. The written PM procedure is the document that tell workers what needs to be done. This document needs to contain all of the tasks that will provide the most thorough inspections and lubrications of machines in planned down time, without exceeding the point of diminishing ROI. Generally, the PM inspections of most machines are one of two types. The first is for any thing that moves or causes some other machine part to move. This needs to be inspected for damage, wear, loose and missing fasteners, etc., and proper lubrications performed. The second is the inspection of static, non-moving machine components such as wiring, plumbing lines and hoses, structural support members, etc., for damage, cracked welds, loose and missing fasteners, etc. These procedures may be lengthy or simple, depending on the type of machines involved. The main concern is that the person writing the procedures is very experienced in plant maintenance and plant engineering. This person must understand and be experienced in all phases of static and dynamic machine principals and actual machine degradation analysis.

"When" PM should be performed depends on several factors. Some machines are simple in design and function and some are not. Typically, there are items to be inspected and lubricated on a daily basis. Other inspections and lubes are progressively more detailed and regularly performed on a bi-weekly, monthly, quarterly, semi-annual and/or annual basis, depending on what is required.

In addition to the machine design and basic function, several other factors help in determining the best time interval between PM tasks. One is the amount of time the machine runs between regularly scheduled shutdowns and/or how much time is available for PM. Does the machine run 24 hours per day, seven days per week, or eight hours per day five days per week? Another factor is the environment in which the machine runs. Is it humid and damp, or extremely hot and dry? Does the machine receive shock loads or run with moderate to high vibration levels? Is the machine subject to chemical spillage or leakage, ultra violet light, etc? Good operating and cleaning practices, or the lack of them, have a significant impact on PM scheduling. In addition, planned shutdowns for plant expansions, machine rebuilds, inventories, vacations, etc., also dictate when some of the more involved PM work can be accomplished.

Predictive Maintenance 101

Most of the above information relates to Preventive Maintenance procedures that are completed on machines while shut down. There are other tasks that are considered Predictive Maintenance (PDM) practices. One of these, usually done while the equipment is shut down, is oil sampling and analysis. Oil samples are taken and sent out to laboratories that specializing in analyzing industrial oils. The cost is relatively inexpensive and provides much valuable information. This process identifies the lubricating ability of the oil; its stability; contents of water, wear metal particles, and dirt; among other aspects.

Another extremely important PDM procedure is vibration analysis. Using a portable vibration analyzer, readings are taken from many points on machines. These readings are direct and extremely accurate measurements of the vibration amounts and frequencies produced by the moving parts of the machine. These vibration amounts and frequencies are used to tell if any parts need replacing or adjustment, and exactly what internal parts are causing problems. Bad bearings, excessively worn gears, and poor coupling alignment can cause excessive vibration, weakened mounting fasteners and many other mechanical problems. Vibration analysis also can tell you if pumps have loose impellers, air cavitation, faulty valves, or mounting problems. In addition, it reveals trending information. When vibration readings are taken, they provide a base number to use as a gauge to determine if and how much internal machine changes are taking place between inspections. This is the very best tool for detecting the correct health of machines and for trending the internal activities inside motors, gearboxes, pumps, large fans, compressors, and many other machine components. There is no better way to detect machine problems before they cause an unplanned shutdown due to a component failure. What's more, the fact that vibration analysis is done while the machines are running in their production modes allows the testing to be done at any time and is especially important for any plant that runs 24 hours per day, seven days per week.

A Comprehensive View of Preventive & Predictive Maintenance

There are many aspects of maintenance and other plant functions that have an effect on the number of machine breakdowns and the length of downtime. Some of these considerations are not normally associated with the term Preventive Maintenance, but nonetheless contribute to equipment failure. Therefore, they should be considered as a part of comprehensive approach to Preventive & Predictive Maintenance.

Proper start-up protocols. Start-up operations; changeover and set-up; and shutdown procedures should be carefully planned and consistently implemented on all machines.
Procedures lists for unplanned shutdowns. Outline what is to be done when an unplanned power outage occurs and what to do before the power comes back on.
Emergency management plans for floods, fire, etc.
Machine component rebuild programs to insure quality and consistency.
Machine cleaning practices and procedures.
Available informational equipment manuals for maintenance personnel.
Solid troubleshooting skills by all maintenance personnel

The above information provides an outline of a comprehensive PM and PDM system. This approach is unassuming and leaves little, if nothing, to chance. While there are many variables to take into consideration, if properly designed, instituted and operated, the PM and PDM system will help to ensure dependable and predictable performance from all serviced equipment, machines, and related processes.