Misconceptions usually surround difficult issues just as they do the subject of condition monitoring and maintenance practices. Based on observations in many industries, I have found three most prevalent and potentially damaging misconceptions. While these misconceptions need to be corrected to ensure healthy communication and productive technical exchange, they nevertheless provide a common ground for discussion of condition monitoring and maintenance technologies.

Misconception 1: Been there, done that

Many organizations and practicing professionals have used various degrees of condition monitoring and maintenance technologies in their routine operations, but they have come to the conclusion that these technologies are not suited for them for lack of consistent, measurable benefits.

Misconception 2: Same old stuff, no new trick

Similar to the group of organizations and professionals holding the first misconception, this group is reluctant to embrace newer technologies or methodologies, although they have not completely lost the hope for possible benefits.

Misconception 3: It is going to cost me

This misconception is frequently held among plant or resource management. Yes, it costs money to invest in (or implement) a good condition monitoring system, but the return on investment (ROI) may very well justify the cost. On the other hand, not implementing effective monitoring and maintenance practices may result in more costs for repair and support.

Evolution of technologies
Historically, a condition monitoring system (CMS) is a ground-based, or an on-board, system that performs some level of monitoring functions. These functions typically include exceedance alert, failure detection, and failure isolation.

The primary goal of a CMS is to help the maintenance crew repair damaged parts in reaction to alerts and failures. Hence, the practice is considered reactive maintenance (RM). As condition monitoring and maintenance technologies evolved, the goal of CMS was extended to failure prevention, i.e., implementing the preventive actions that are time-based (or schedule-based such as periodic inspections) to detect abnormal conditions and repair faulty parts. This type of maintenance practice is considered preventive maintenance (PM). More recently, CMS capability has been expanded to failure prediction, i.e., to predict when a failure will progress to the point where the service of equipment will be disrupted. This practice with an emphasis on failure prediction and associated maintenance actions is considered predictive maintenance (PdM).

To implement PdM effectively, a CMS must be able to identify root causes and optimize maintenance actions. Hence the PdM with an emphasis on the analysis of failure mode and effects as well as root causes is sometimes considered proactive maintenance. The maintenance practice driven by PdM or proactive is condition-based, hence it is also called condition-based maintenance (CBM).

While RM, PM, PdM, and CBM have been the terminologies commonly accepted in the industrial sector, a different set of terminologies has been adopted for the aerospace and defense sectors. An objective of this discussion is to bring condition monitoring and maintenance technologies in these different sectors together and to facilitate a sharing of best practices.

Since flight safety and airplane readiness are critical to mission successes in the aerospace and defense sectors, the development of monitoring and maintenance technologies has been accelerated. Aircraft condition monitoring systems (ACMS) and engine monitoring systems (EMS) have been implemented on flight vehicles for decades. Engine health management (EHM) systems, whose capability goes beyond the traditional recording and alarming functions of a CMS, have been implemented in helicopters for two decades (e.g., health and usage monitoring system, HUMS).

Since the mid-1980s, the reliability-centered maintenance (RCM) process has been applied to the aerospace and defense sectors. In the late 1990s, emphasis was further placed on the modeling and reasoning aspects of failure prediction as well as on the life extension of critical engine parts. Hence a total solution concept is evolving that tightly integrates monitoring, maintenance, logistics, and operations.

This total solution philosophy is called prognostics and health management (PHM) for the joint strike fighter under development by several countries armed forces. PHM aims to detect a wide range of operating conditions, including known failure modes, intermittent faults, and anomalies, while eliminating false alarms and missed detects. It also aims to prognosticate potentially damaging conditions based on the anticipated operating environment and available resources, i.e., spare parts. The U. S. Army considers this type of concept anticipatory maintenance. PHM or anticipatory maintenance expands PdM by providing a complete solution for engine or equipment health management (EHM).

Health management
An effective health management solution consists of four major steps:

• Measuring key system operational parameters
• Identifying abnormal conditions and predicting incipient failures
• Determining maintenance actions that make the best business sense
• Scheduling and controlling maintenance work.

These steps address the four fundamental questions of a comprehensive condition-based maintenance solution: where, when, what, and how, respectively.

Maintenance Intelligence
In the health management process, the two middle steps provide all the necessary functions from data analysis and prognostics to recommended maintenance actions. These steps form the Maintenance Intelligence (MI) that is essential to support the business objectives of equipment operators or owners.

Maintenance Intelligence consists of six major functions: data analysis, anomaly detection, health assessment, prognostics, life prediction, and maintenance decision support. Anomaly detection, health assessment, and prognostics are all related to abnormal conditions. Abnormal conditions occur at various stages of equipment service life. Depending on the stage in equipment service life and when the measurement is taken, abnormal conditions are classified and detected differently.

Anomaly, fault, and failure
Abnormal conditions can be classified into three groups: anomaly, fault, and failure. While many practicing engineers and maintenance associates consider them similar or synonymous, we prefer to look at them separately in the failure progression process. Anomaly is a type of abnormal condition.

We can define the functions of anomaly detection, health assessment, and prognostics as follows:

• Anomaly detection performs the function of detecting unknown abnormal conditions.
• Health assessment performs the function of detecting faults under known failure modes.
• Prognostics performs the function of predicting when the failure will occur after a fault condition is detected.

In some applications, predicting remaining life of equipment is included in the prognostic function. However, to be consistent with the scope of identifying abnormal conditions in anomaly detection and health assessment, we favor the idea of separating the life prediction function from the prognostic function, because predicting remaining equipment service life needs to consider factors other than failure state.

Decision support
Maintenance decision support acts as a bridge between condition monitoring and detailed maintenance task planning and scheduling. As described previously, condition monitoring identifies abnormal conditions and predicts when such conditions will deteriorate to disruptive failure states. Decision support takes the condition monitoring information and combines it with operations information to recommend the most adequate maintenance actions based on desired business objectives. After these maintenance actions are determined, detailed work tasks are planned and scheduled by a work control tool, typically an enterprise asset management or computerized maintenance management system.

Decision support is when condition monitoring information is transformed into maintenance actions so the benefits of increased equipment service life (or uptime) and decreased cost of ownership can be realized.

Business intelligence
The key to CBM is Maintenance Intelligence. It is essential for the kind of business intelligence that drives operational efficiency and enterprise excellence. Four types of systems are usually implemented in manufacturing or production facilities (or systems): control and operating system, monitoring system, maintenance system, and management system. The success of each individual system ensures the success of the enterprise.

Obtaining Maintenance Intelligence requires the application of many different analytical methods, ranging from traditional physics-based modeling to artificial intelligence (AI). An AI or a smart system usually contains a component of expert system, fuzzy logic, or neural network (NN). These smart components complement traditional analytical methods for information processing.

An artificial neural network is a mathematical tool modeled after biological brains. The primary advantage of NN over the traditional method is its learning ability, i.e., to learn patterns and features. This advantage makes NN a powerful tool in handling time-varying characteristics such as a fault signature or time-elapsed deterioration. It also offers significant benefit for implementing predictive models. See accompanying section "Advantages and Limitations of Neural Networks."

While NN processes numeric information, fuzzy logic and expert system process symbolic information. The fuzzy logic method is especially powerful in handling multi-valued computations; hence it is useful for reasoning or diagnostic functions.

A hybrid approach that combines both traditional and smart analytical methods and is capable of handling both numeric and symbolic information has proven to be most effective in obtaining Maintenance Intelligence.

A CBM or an equipment health management solution is the modern phrase for condition monitoring, health assessment, maintenance decision support, planning, and control. It supports RCM and PHM philosophies. It is manifested in PdM and proactive maintenance practices. Its significance extends beyond equipment monitoring and repair into enterprise management and business intelligence.

A critical link in the CBM process is Maintenance Intelligence. At the center of Maintenance Intelligence is decision support. Maintenance decision support is the bridge between monitoring and maintenance. It is also the driving force for realizing such business objectives as reduced equipment downtime, optimized spare inventory, leveled work scope, and reduced cost of ownership. MT

Dr. Link Jaw is the president and founder of Scientific Monitoring, Inc. (SMI), 4801 S. Lakeshore Dr., Ste. 103, Tempe, AZ 85282-7156; (480) 752-7909.

Energy management in compressed air systems can be divided into two sectors: demand side and supply side. Once the energy constituents of demand in the system have been determined (MT 9/01, pg. 21, and MT 10/01, pg. 21), we must determine how effectively we are using energy to support the usage. In most systems, much of the demand usage is a constituent of the supply energy.

There are a number of ways that energy is consumed in an industrial air system besides the obvious. Some of these are very interactive and difficult to isolate, but they must be addressed in a typical plant compressed air system. Remember that air systems are extremely dynamic.

In auditing most systems, there is a common problem that always surfaces in the supply side of the system. The issue is ownership. Responsibility in the system is broken up between supply and demand, often with no one responsible for the demand side of the system. Preventive maintenance normally is performed by maintenance personnel. Overhaul and annual maintenance often is contracted to compressed air service organizations. It is assumed that these personnel are adjusting the equipment for its efficient operation. Often, this is not the case. The following problems are typical.

Problem: A service contract is issued with no discussion or understanding of the objectives of the owner. Preventive action: Establish service objectives.

Problem: The owner, out of a lack of knowledge, assumes that the right things will be done. Neither party understands that the way the system operates must be owned by someone. Preventive action: Designate a compressed air system manager.

Problem: The equipment is adjusted to factory-recommended set points and signals when it is installed. This has nothing to do with either how the system will work or efficient operations. In most cases the equipment is never readjusted for its useful life unless the controls are replaced. Preventive action: Periodically audit system performance and adjust set points as needed.

Problem: No one, including the service vendor and the operators, has any records of how the equipment was originally adjusted. No discussion occurred about how the system should work, other than meeting a minimum acceptable pressure. Preventive action: Document system history.

Problem: "Keep the equipment running" is a vague protocol that assures energy waste and high operating cost. Preventive action: Establish a rational approach to system management that can allow unused equipment to be taken off line and adjust signals, set points, and control philosophy accordingly.

These preventive measures must be revisited each time demand changes or a piece of supply equipment is added, deleted, or replaced, and the operating approach adjusted appropriately. If not, the system energy efficiency and system effectiveness will suffer.

The following 11 items are issues that affect supply energy in the tyical system.

1. Demand usage

Demand usage is the amount of energy necessary to support consumption assuming no inefficiency in the system. Factors affecting demand were discussed in previous articles (MT 9/01, pg. 21, and MT 10/01, pg. 21).

2. Temperature and relative humidity of intake air

Using standard conditions as a normalized value, higher temperatures at the inlet of a compressor provide less dense air and result in less compressed air mass. Because the compressor produces less results in terms of mass or work energy, more energy is required to produce the identical results systemically achieved at lower temperatures. Dynamic and positive displacement compressors respond differently, but the systemic results are comparable. When the inlet air represented is based on volume with no regard to density, one can easily overlook this issue and the corresponding energy required.

When the temperature drops, the air is denser and the compressors will produce more mass to the system using more energy. As work energy in the system is our objective, inlet density or mass is a necessary component of determining the power required and the number of compressors to support all conditions relative to the system. At 0 F without the effect of relative humidity, you will produce close to 12 percent more air by mass and an equivalent amount of energy than at standard conditions. At 100 F without the effect of relative humidity, you will produce at least 7 percent less air by mass and an equivalent amount of energy.

Higher relative humidity implies that there is more water present in the air at the compressor intake. Because water does not compress, it reduces the amount of net air that can be compressed. Relative humidity can influence the net result by as much as 3.5 percent less displaced mass.

When effects of temperature and relative humidity are combined, there can be as much as a 22.5 percent swing in performance on the compressors in the system from 0 F at 1 percent relative humidity to 100 F at 100 percent relative humidity.

When you compare the demand requirements including trim and conditional loads against the inlet condition profile, the amount of energy needed will be a function of the size of the compressors used. The larger the compressors as a percentage of the total requirement, the more part loaded a large unit will be depending on conditions and load. The smaller the compressors are, as a percentage of the total requirement, the less part loaded any one compressor can be. When properly controlled, the arrangement and size of the units vs. the needs profile can represent as much as 33 percent less power systemically at the lowest temperature and load.

3. Compressor optimization

The primary objective of compressed air system management is to get the most mass per kilowatt of electricity. The more mass you can achieve in any one compressor in the system, the fewer compressors you will need to accomplish the same results. Throughout this article, mass refers to pounds mass (volume at density).

On positive displacement compressors, the volume is fixed within the operating pressure of the compressor. As you elevate the pressure within this range, the volume will remain constant as the pressure and power increases. This is an increase in mass. As you exceed optimum, the mass will become constant and/or the motor efficiency will begin to drop. The pressure and energy will increase, but the mass will remain constant. In our experience, optimum will be achieved within a compressor frame range at a higher pressure in the bottom of the frame and at a lower pressure in the top of the frame. This is a result of packaged losses that increase in the top of a frame.

On centrifugal or other types of dynamic compressors, optimum is achieved in a slightly different manner. There are zones on the performance curve. A portion of the curve will produce constant mass. This implies that as the pressure rises and falls the volume will change inversely and maintain the amount of mass.

Above and below this zone of performance, either the pressure will drop faster than the increase in volume or the volume will diminish faster than the rise in pressure. Both of these zones will produce less mass. The power does not diminish as quickly as the mass in these zones. You would have to determine at what pressure you would displace the most mass per kilowatt of electricity by carefully examining the curve of the compressor at the typical and extreme inlet conditions of intended operation.

The confusing issue with centrifugal and dynamic compressors is that the performance curve moves with changes in inlet temperature. It will drop and move to the left as the inlet temperature increases, and rise and move to the right as the inlet temperature drops. This would require adjusting the operating pressure and the current limit adjustments on temperature change to stay within this optimum range. If the curve is generous enough for your conditions, you may be able to operate at relatively little performance change despite conditions.

The number of stages and the design will determine at what range of pressure this can be achieved. Optimum is normally achieved at the lowest pressure in the constant mass zone of the curve, which uses the least amount of input power for the mass achieved. We have found that factory-supplied curves only show performance between maximum stable flow and the surge pressure of the unit. More than half of the compressors of this type that we evaluate are operating at least a portion of the year below the pressure and temperature where you will find maximum stable flow (not mass).

If you continue down the curve from this point, the volume will become constant as the pressure drops and the energy either remains constant or diminishes. This is referred to as the choke zone. In the choke zone, you lose the advantages of this type of compressor. Further down the curve the volume will diminish as the pressure drops. This more-than-linear loss of mass is called stonewall where you will achieve sonic velocity through the unit.

Neither the choke zone or stonewall are shown on factory-supplied charts. We would suppose that this is not shown because you should not operate in this manner. Nevertheless, we frequently find compressors that have set points of operation below maximum stable flow and well below optimum. We also seldom find compressors operating on the curve. Most of the time they are operating in modulation or throttle. If the curve were extremely vertical, where there is very little volume turndown on the curve, you would have to operate at a low relative pressure in throttle to prevent surge. It should be obvious that examining the curves in terms of mass at pressure including minimum stable mass at various pressures and inlet conditions is the only way to determine the best operating set points for efficient performance.

You also should request that the curves show throttled performance at pressure and power at these various pressures and inlet conditions. Despite this need, we did not encounter one facility in the past 250 audits that had enough information to determine the best way of operating the compressor. In fact, most owner/operators have never seen curves, even during the selection process. Since this information is obviously needed and has never been produced, one must be curious how factory required service technicians adjust the units in the field. Our experience is that keeping them running is the approach taken, not optimization. Factories need to train their service personnel and the operators in performance optimization of both the individual equipment and the system using actual performance data and curves rather than typical factory set up suggestions.

4. Compressor cooling temperature

All compressor performance is influenced to some extent by the temperature at which the unit is cooled. There is a considerable difference in types of compressors. The displacement can be influenced by 0.5 percent to 3.5 percent of rated capacity for every 10 deg F increase over rated cooling media temperature. The inherent inefficiency, combined with the range of cooling media temperature and the maintenance condition of the coolers on the compressor, can effect the displacement efficiency by as much as 25 percent on the most temperature-sensitive types of compressors. Centrifugal compressors should be tested for natural surge and throttle surge at least twice a year to determine the performance decay of the unit as a result of cooler fouling.

You must record the inlet conditions during these tests so you can compare actual performance against theoretical performance for these conditions. Factory service personnel should either teach operating personnel how to perform these tests or provide this test data to maintenance personnel on a regular basis if you wish to minimize onboard energy and perform maintenance as required.

5. Systems storage vs. rate of flow of the largest event in the system vs. loading time required for the next available compressor

The more storage capacity in the system, the less the pressure will fluctuate on any demand event. This will allow you to maintain all of the compressors that need to be operating closer to optimum. The slower the speed that it takes to turn on the motor and load the next compressor, the more the pressure will drop. You should be able to add trim compressors to the system with a minimum delay and pressure drop. When this process doesn't work well, and the pressure fluctuates too much, the normal reaction is to put all compressors in modulation and keep them on line regardless of demand. This will avoid the fluctuation or pressure decay, but not without a considerable increase in energy and operating cost.

Another anomaly is that as demand increases, the supply pressure drops. When the pressure drops on all of the compressors that are base loaded, there is a loss of isothermal efficiency proportional to the decay in the density of the compressed air. In most systems, as the demand increases and you require more mass, the compressors that are operating produce less mass. This causes the pressure to drop exponentially. As you need more, you can become less efficient with pressure decaying at an accelerated rate.

Careful design of control storage and thoughtful selection of set points, signal locations, and operating logic is necessary to achieve any relative efficiency from the system. Single set point, rate of change automation is the best approach to maintaining optimum system performance.

6. Resistance to flow in the system's piping and downstream point of use components

The highest point of use pressure requirement is determined by the highest article or inlet pressure on the air-using equipment plus the highest installation differential across the point of use transmission components such as filters, regulators, lubricators, disconnects, hose, and fittings.

Original equipment manufacturers install smaller transmission components with high differential pressures to control manufacturing costs. The user of the equipment must compensate by providing high initial pressures from the plant air system. The tradeoff between high operating costs and the price of equipment with lower operating pressures or differentials is an important but rarely considered issue. Typical pressure drops across accessories on air-using equipment have increased substantially in the past 15 years. As long as this is a non-issue among the purchasers of this equipment, you may be assured that manufacturers will continue to use differential pressure as a tool for controlling manufacturing costs.

The highest differential is achieved at the highest flow, highest inlet temperature, and the lowest pressure. All specifications should incorporate this information in performance queries and specifications with maximum differential being the desired response. Compressor manufacturers report that elevating the pressure 1 psig will increase power by 0.5 percent of the total connected onboard energy. If you are operating with the compressors in load-no load mode and the elevation of pressure does not increase the demand in the system, then this is true.

Unfortunately, most systems are in modulation and do not have a demand control or expander. The elevated pressure then will cause demand to increase. The demand increase will be a function of the percentage of unregulated demand including leaks and points of use with regulators adjusted to the maximum setting. The power will increase proportional to the pressure increase adjusted for the percentage of unregulated demand plus the 0.5 percent per 1 psig rise. If the increased demand does not require an added compressor, the influence on energy will be between 0.5 percent to 1.575 percent of the total connected brake horsepower (bhp) from 100 percent regulation at the point of use and no leaks in the system, to 0 percent regulation plus leaks respectively per 1 psig rise in operating pressure.

If you are in modulation, and must add another compressor in order to increase the pressure, the new compressor will support a portion of the added load, but the total volume will be shared across all modulating compressors. This can be so inefficient, depending on the degree of part load prior to the add, that the effect of a pressure increase can be 25 percent or more for a 1 psig pressure increase if another compressor must be added. We haven't seen a system without leaks, nor 100 percent regulated below the lowest compression pressure. Compressor manufacturers do not field test how their units are influenced in systems, only packaged results. So much for the 0.5 percent per psig of pressure rise.

7. Differential pressure across supply components downstream of the compressor control signal location

Differential pressure influences system energy in the same manner as in item 6. Filters that degrade will cause the downstream pressure to drop. Typical of these components would be aftercoolers, separators, filters, and dryers when the compressor signal is located upstream of the aftercooler. Specified performance never includes the influence of differential. This must be determined at the highest flow, lowest pressure, and highest temperature as with point of use equipment. What is unique is that the differential will ride on the system's pressure and drive backwards into the compressor's operating pressure signal.

If the operating philosophy is to turn on compressors to maintain a system pressure of 100 psig, the pressure drop across the clean-up equipment will drive the control signal up accordingly. If the clean up differential pressure is 10 psig, the signal pressure would have to be maintained at 110 psig to maintain a system pressure of 100 psig. As you need more air, the differential will increase at a higher rate of rise than the dropping system's pressure.

The more you need, the harder it will become to satisfy the demand, and the more likely you will turn on the next available compressor to share the load.

8. Higher internal pressures resulting from differentials across components upstream of the compressor control signal

This is where the compressor control signal is downstream of all or some of the components as in item 7. In this case, the differentials increase the internal pressure in the compressor. In this case only, the compressor energy will increase 0.5 percent of the total connected bhp per psig for this internal pressure rise.

The same would be true of an air to lubricant separator on a rotary screw compressor. As the filter/separator dirt loads, the upstream internal pressure rises, increasing the motor bhp. The separator is upstream of the control signal. The increase in energy we are discussing is only true as long as there is motor capacity available. Once you have consumed all of the available energy, either the displacement will diminish, the motor will overload depending on the compressor type, or you will have to add another compressor. The differential and the energy will rise and fall with the change in the compressor volume, but the system will not see the effect of this, only the drive motor.

9. Resistance to flow on inlet filters and their effect on reduced inlet pressure to the compressors

As the inlet filter becomes loaded with dirt, the dry inlet throat pressure drops proportionately. If the compressor is not fully loaded, it will increase in load to achieve the desired result as a consequence of the controls set point at the reduced inlet pressure. The effect will be different depending on how the compressor is operating.

In load-no load mode, the increase will be in more load time. The energy increase will be proportional to the ratio of the atmospheric pressure divided by the added differential. This particular differential is measured in inches of water and needs to be corrected to pounds/sq in. for the ratio (27 in. static pressure water gauge equals 1 psi).

If the compressor is in modulation, the effect on energy can be more or less than linear depending on the load on the compressor at the time that the inlet pressure reduction occurs. Power is anything but linear in modulation. Based on manufacturers' recommendations for filter changes, most systems will increase power by 2.3 percent to 3 percent during the time between when the inlet filter is clean and when it is sufficiently dirty to require change. If this causes the need for another compressor, the influence increases the power dramatically.

10. Inefficiencies resulting from how the compressor controls are set up and their effect on unit performance

The effect of improperly set controls can increase energy consumption by a modest amount to as much as 33 percent of the total connected kilowatts. A system control setting is a very complex matter requiring a great deal of understanding. Previous discussion outlined the general effects of the demand system and the supply components on energy usage. This actual influence is specific to the interrelationship between the compressors, their signals, set points, and differentials within the system. This complex subject is outside the scope of this article but is covered fully in a 90-page section of the author's "Compressed Air Systems Solution Series."

11. Fouling of internal components on the air path of the compressor

Fouling of internal compressor components is specific to dynamic compressors such as centrifugal and axial types. The dirt and condensibles from the inlet loading on impellers and diffusers can cause considerable performance losses. As this occurs, the surge pressure usually drops in the compressors. Natural surge testing can assist in determining whether this condition exists. You can also observe whether the unit is performing in terms of mass at pressure and power comparing test results against rated performance on its curve.

Measuring and managing energy
For the most part, compressors have no power monitoring equipment on them. In the infrequent case where there is, the compressor is monitored with an amp meter measuring current to the motor. Current is not an accurate means of monitoring power on a compressor because of the relationship between mass and input power.

Monitoring and trending total and individual input power is perhaps the best means of trending operating cost and predictive maintenance issues. The only accurate method we have observed is using kilowatts, relative to full and part load performance.

Compressors and systems do not usually fail. They degrade. If you trend individual compressor input power vs. status and system efficiency, you can easily avoid an interruption without the extravagant application of power as an alternative. You need to monitor the total mass at pressure on the demand side of the system and trend the demand mass divided by the total input kilowatts.

Although many of the individual compressed air energy issues have been understood for some time, it has only been in the past five or six years that the interrelationship of a system's supply and demand has begun to be understood. The improvement in and quality of information applied and trended systemically has provided the best basis for separating the theoretical from the actual. The commercial emphasis in compressed air has always been with the equipment. Much more emphasis must be placed on systems and their operations at all levels including system operations, production usage, sales engineering, contract field service, and equipment manufacturing.

The remarkable opportunities available for operating cost reduction and quality improvements in production are a strong indication that there is much work that needs to be done in this area of plant asset management. Many of the poor decisions that are made are out of fear of not satisfying production. Fear is only present in the absence of knowledge. Education, ownership, and the application of information are the beginning of more effective plant air systems. MT

R. Scot Foss is president of Plant Air Technology, P.O. Box 470467, Charlotte, NC 28277; telephone (704) 844-6666. He is the author of "The Compressed Air Systems Solution Series," 1994, Bantra Publishing; (704) 372-3400.

For the maintenance staff of the Hickory plant, the expansion posed an enormous challenge. Corning technicians were faced with the task of maintaining more than 300,000 additional sq ft of plant space without compromising the speed or quality of their work. In addition to tackling the mounting workload, the Hickory plant's management needed to improve its ability to capture performance data to generate more accurate and timely records.

To manage its maintenance operations, Corning had been using MAXIMO from MRO Software, Bedford, MA. "Typically, our technicians would walk up to a terminal, write down work order information on a sheet of paper, and then walk off to complete the job. Sometimes technicians would be lined up two or three deep at a terminal to receive their next work orders. We realized there had to be a more efficient way of getting that information into their hands," Lawrence Bugielski, CMMS coordinator at the Hickory plant, said.

Mobile technology is the solution
Corning searched among several technology providers for a solution before selecting SMART from Syclo, Barrington, IL, which is built on the company's Agentry platform and works as a companion to MAXIMO.

Tradesmen use Windows CE-based handhelds as electronic clipboards to send and receive work orders and other workflow data to and from the CMMS. SMART provides data at the point of performance, eliminating reliance on time-consuming paperwork and allowing technicians to accomplish more maintenance tasks in the field. It also combines a variety of communication optionsùwireless, dial-up, or docking cradleùwith synchronization capabilities to ensure that users can work effectively in and out of wireless network coverage.

"After researching the available technology, we recognized that this was the best solution to replace our system of fixed-point access to the CMMS with a more efficient mobile operation," Bugielski said.

The system was up and running quickly for Corning, whose technicians found the solution easy to learn and simple to use. Beginning in August 2000, it was deployed for both Corning's break-fix team and its preventive maintenance (PM) operation.

Swift productivity gains
The installation at the Hickory plant produced swift, measurable results. Using Hewlett Packard Jornada handheld PCs and synchronizing with the CMMS via conveniently located docking cradles, Corning technicians soon recorded a significant increase in the amount of work they were able to complete.

By providing work orders and other important data to technicians at the point of performance, the system eliminated the need for Corning technicians to walk back and forth between terminals to handle data entry, saving them an average of 1 hr per shift. With more time in the field to complete their maintenance tasks, Corning's tradesmen are able to help the newly expanded plant run much more smoothly. The system also eliminated the plant's reliance on costly, time-consuming paperwork, which had slowed its productivity in the past.

"Our decision to combine handhelds with our CMMS has resulted in so much more completed work that it's almost as if we doubled our staff of tradesmen," Bugielski added.

In addition to boosting the amount of work completed, the deployment also has helped Corning ensure that the Hickory plant's operations meet manufacturing standards set by the International Organization for Standardization (ISO). The plant's maintenance staff is using the system to perform condition monitoring and rounds-and-readings activities to make sure equipment is running at peak efficiency.

"Our customers are investing a lot of money in the fiber-optic cables we produce and it is essential to assure them that our manufacturing facility meets all of the quality checkpoints," Bugielski said. "By collecting more accurate and timely data, our PM operations have improved and we are better able to meet and exceed our ISO requirements. The system helps us maintain the quality that our customers expect and rely on."

Corning Cable Systems has achieved a number of benefits since deploying the mobile technology:

• Technicians are saving an average of 1 hr per shift by eliminating their reliance on paper work orders.
• The plant maintenance staff has dramatically increased the square footage supported by each maintenance technician.
• After the full rollout, the Hickory team was able to maintain equipment for a plant expansion of 300,000 sq ft with the same number of technicians.
• Tradesmen perform condition monitoring and rounds-and-readings activities to make sure equipment is running at peak efficiency. By capturing more timely and accurate data, management has improved its PM operation and ensured its adherence to ISO operating requirements. MT
  

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Robert M. Williamson, Strategic Work Systems, Inc.

From my perspective it's not an either-or question. Why does it have to be one improvement program at a time, fully implemented, over three to five years? What we really need is to systematically identify and eliminate the causes of poor performance using the appropriate tools or techniques—in a sustainable manner of course. I've said it before, and here it is again: Focus on results and change the culture along the way.

Our culture has a history of looking for the "silver bullet" or the "secret ingredient" to successful equipment management. We tend to single out one improvement program and go whole hog to implement it. A giant leap of faith—hoping that equipment will perform better, last longer, and operate at lower costs. Then the "new program" comes along and interrupts what we started. We never seem to fully realize the fruits of our former labors before we have to shift gears. Or, in some cases, we start seeing the results but are unable to sustain them because the new initiative-of-the-month has priority.

Can it be that the top decision makers are so desperate for improvement that they keep looking for another, and another, and another silver bullet?

In the late 1980s the term Lean Manufacturing was coined by a researcher in the international motor vehicle program at MIT when comparing many of the mass-production approaches with the Toyota Production System (TPS). But since then, as Lean concepts started catching on, they often were taken out of historical context and the maintenance elements fell by the wayside. The silver bullet syndrome again?

Just last month, Portland, OR-based Productivity, Inc. hosted its 6th annual Lean Management and (12th annual) Total Productive Maintenance Conference in Detroit. This was the first time that a maintenance improvement theme (TPM) was brought into the context of Lean Manufacturing, Lean Production, and Lean Enterprise that I can recall. This combination of two previously separate, and seemingly unrelated, improvement strategies has laid another big foundation stone for yet another breakthrough in Lean thinking and equipment and reliability improvement. But the significance of this combination may be overlooked by the Lean consultants.

Yet, just a little over 30 years ago Japanese automotive supplier Nippondenso realized that until you address and systematically eliminate the causes of poor equipment performance you cannot deliver to your customers just in time, nor improve quality levels, nor lower operating costs, nor improve profits. In 1969 the ideas of TPM facilitated by Seiichi Nakajima helped take the TPS to the next level. Since the TPS was focused on the absolute elimination of waste to reduce manufacturing cost, TPM was designed to systematically identify and eliminate equipment losses (downtime, inefficiency, defects).

We have an opportunity. As maintenance and reliability professionals we need to help our "Lean thinkers" understand the relationship between getting Lean and equipment reliability and performance improvement. It's not one or the other, it's both. You cannot have a Lean manufacturing facility without reliable equipment. Conversely, you can have reliable equipment without Lean. But the key to sustaining equipment reliability comes in building a capable infrastructure—one that not only supports and encourages equipment reliability at all appropriate levels but links reliability to the needs of the business, to deliver business results. That capable infrastructure is essential for sustaining any improvement initiative—including Lean.

Until we help lead maintenance and reliability as a core business strategy, our efforts will remain just another maintenance program. It's up to those of us who understand maintenance and reliability methods to collaboratively build the bridges between our reliability improvement efforts and Lean transformation efforts in our plants and facilities. Planned, preventive, predictive, proactive, total productive, and reliability-centered maintenance are known and proven.

Robert C. Baldwin, CMRP, Editor

The examination is designed to validate the examinee's skills and knowledge in five interrelated work processes: Equipment reliability, manufacturing process reliability, work management, business and management, and people.

Individuals who pass the test and agree to abide by certain guidelines for professional conduct become certified and can proudly add the initials CMRP after their names. They have the right to a large measure of personal pride because their proficiency in maintenance and reliability management is at a professional level certified by their peers as represented by SMRPCO.

Because I participated in the development of the examination, I was not eligible to obtain certification by examination. However, through SMRPCO "grandfather" provisions, I can use CMRP in my byline, and I am proud to do so. Not having sat for the examination, my sense of pride is different from those who did. I feel proud to have the privilege of working with SMRPCO in the development of the CMRP process.

In my estimation, the person deserving the greatest sense of pride in CMRP is Brad Peterson, a fellow founding member of SMRP. Without his vision, leadership, sense of purpose, and years of hard work as chairman of the committee, there would be no CMRP. His insistence on rigorous process development and excellence of execution was essential to making CMRP unique in several ways:

• Independence: SMRPCO is a practitioner-based organization without ties to any commercial venture.
• Body of knowledge: SMRPCO recognizes management and manufacturing skills as well as the technical aspects of maintenance and reliability.
• Validation: SMRPCO validated each step of the process with input from a broad cross section of the maintenance and reliability community.
• Certified process: SMRPCO work was conducted according to National Organization of Competency Assurance guidelines with the intent to have the process certified by that organization.
• Continued enhancement: SMRPCO has a plan to continue to enhance the value of certification to practitioners who have become certified.

I believe SMRPCO's CMRP is a profession milestone in which all present and future participants can take pride. MT