Tune Up Your Condition Monitoring Program by Answering the Five W s

Transcription

1 Tune Up Your Condition Monitoring Program by Answering the Five W s Robert P. Madding, RPM Energy Associates, LLC William Woyshner, WSC International, Inc. ABSTRACT If you or your management bought an IR camera for condition monitoring (CM), its use should be integral to a well-planned CM program. If you plan on doing IR by walking around when time allows, you are going to have limited success. You need to work within a robust CM program to achieve beneficial results. If you find a problem and no one fixes it, you have lost an opportunity. A useful tool to evaluate your CM program is to answer the five W s. One of the first lessons a news reporter learns is every article/report should answer these questions: Who, what, when, where, and why. This presentation gives an overview to the CM program answers to the 5 W s and describes how a good CM program can evolve from them. For example, the who is not just the IR thermographer, the vibration analyst, or other diagnostic specialist. For an item that needs repair, it is who finds the problem, who determines its severity, who makes the repair decision, who schedules the repair, who does the repair, who writes up the repair, and who does the follow-up work. Answering who defines the roles and responsibilities for the entire CM program group. Implementing the answers to all the W s for your CM program will make it stronger. INTRODUCTION Working with EPRI M&D (Electric Power Research Institute Maintenance & Diagnostics) in the 90 s, we developed state-of-the-art methods for a robust Condition Monitoring program. We called it Predictive Maintenance, PdM, in those days. Since then the name has evolved along with many of the techniques, software and technologies. Now we say Condition Monitoring or Condition-Based Maintenance, perhaps due to a few overzealous managers who asked When will this component fail? often the first question, but a question quite difficult to readily answer except in general terms. But it s called Predictive Maintenance, isn t it? So, predict. The basics haven t changed and we wish to focus on them with the simple 5 W approach. Getting the W s right provides an excellent foundation for success whether you create your own reports and databases, purchase tools from an outside source, or implement some combination. WHAT Let s start with What as our first W. First of all, what is Condition Monitoring? Condition-Based Maintenance, CBM, is really the same as Condition Monitoring, CM, though CBM is a stronger term for maintenance personnel. (Another issue with maintenance is CM often refers to Corrective Maintenance. But not in this document.) This paper uses CM and CBM interchangeably. The definition of Condition-Based Maintenance is: a process that requires technologies and people skills, which combines and uses all available direct diagnostic and performance data, process parameter trends, operator logs, and visual inspections to make and communicate timely recommendations regarding corrective actions or maintenance requirements of major/critical equipment. To implement a CM program, you need to know what you have in your facility that lends itself to condition monitoring diagnostic tools. Use your equipment list. In the 21 st century, most companies have an equipment list in electronic form. If you don t, you need to create one. And you need to label the equipment in the facility so it jibes with the list. There must be an unambiguous connection between a component in the facility and the equipment list. Otherwise, reporting a problem becomes difficult and prone to error, usually leading to a costly event. If you can t find it, you can t fix it. A good and simple approach is to use something like the Excel spreadsheet approach shown in Figure 1. The first two or three columns are devoted to the equipment list. This example is part of a power generating station s equipment list. They designated the first 4 columns to describe the unit, the system, the equipment 1

2 name, and the component ID number. The CM team needs to review and sort this list with operations, engineering, and management in order of equipment criticality from most critical to least critical. Each row represents a piece of equipment such as a pump, motor, motor controller, etc. Don t get overly detailed, such as inboard and outboard bearings on a motor, for example. Keep it at a level people can relate to. A diagnostic report can add necessary detail for a given item. Column 5 shows the priority; in this brief example, all items are priority 1. Column 6 indicates the visual inspection which should be done for all diagnostic technologies. The next several columns list diagnostic technologies used by the CM team, as well as monitoring technologies. The last column represents the equipment owner. Many facilities have found that ownership of equipment enhances its reliability. The equipment owner will get reports and it is her/his job to be sure there is follow through on recommended actions such as scheduled repairs, follow-up diagnostics, and then ensure that these are done in a timely fashion. Ownership attributes include: Managing component reliability/availability Performing equipment assessments Updating/managing of component health status/reporting Being the first called when component health is questioned Creating component maintenance task basis.(preventive M template) Ensuring continuous improvement of the maintenance task balance Figure 1. Equipment & condition indicator matrix example. The equipment list can have several hundred items and is quite a chore to generate the first time. Keeping it updated is not as difficult, but just as important. Another important element of What is what areas of a piece of equipment does one examine for a given technology. In IR assessments, the CM thermographer must be very skilled in exactly what parts of equipment items lend themselves to thermal imaging. For mechanical applications, we re talking about bearings, couplings, belts, motor casings (which could actually be something electrical happening internally), gear drives, (some) steam traps, and so on. For electrical applications, we re primarily talking about electrical connections, plus overloads, load imbalance, induction heating, and so on. These are in motor junction boxes, motor control centers, cable trays, switchgear, etc. 2

3 The value of IR windows is fast becoming recognized as a real cost-effective way to improve safety and IR survey efficiency. Frankly, IR windows are really the only viable, safe way to look at motor junction box connections with the motor running. Yes, we have performed IR on live 4160 volt switchgear after the electrician removed the covers, but IR windows would have been much preferred. Knowing what detailed components of the equipment to survey and evaluating problem severity based on the IR images and other data such as load requires training, skill, and experience. The equipment and condition indicator (E&CI) matrix in Figure 1 can readily be converted to an equipment condition status report as shown in Figure 2. Figure 2. Equipment condition status report example. This report is used by management and maintenance schedulers. It needs to be relatively simple. Hyperlinks will allow the user to get more detail if needed. In this example, a hyperlink has been inserted to show an IR image of the overheating fan belts as shown in Figure 3 (Example only, not an actual forced draft fan motor). Be sure to include a hyperlink back to the report. Use of an icon such as a chain link alerts the user. Figure 3. Hyperlink example IR image of overheating belts and bearings. Microsoft Excel has the ability to color-code a cell based on its value. Use the Conditional Formatting Rules Manager feature. Fill, font color, font type, font size, border, and so on can all be formatted based on cell values. Figure 4 shows conditional formatting of the example report used in Figure 2. 3

4 Figure 4. Conditional formatting rules manager showing fill color for various status values. Some reports list estimated avoided costs as well. Often such numbers are difficult to get agreement on. But if you can get buy-in, showing the avoided costs for implementing CM can really help support your program efforts. There seems to be a natural cycle in CM where after the first two or three years the diagnostic technologies find fewer problems. This is the good news and demonstrates the CM program works and has value. The bad news is management too often perceives the need for CM has lessened. CM program reduction can occur, things begin to fall apart after a year or two, then someone says What about Condition Monitoring? and we start the cycle once again. The Equipment and Condition Indicator Matrix and the Equipment Condition Status Report are the primary reports that need to be generated. Other important reports include: Planning and Estimating Guide Critical Component Condition Periodic Diagnostics - Raw Data - Trends - Exception Reports (Exceeds Limits) Continuous Monitoring - Raw Data - Trends - Exception Reports (Exceeds Limits) Troublesome Equipment List Continuous Monitoring Summary Periodic Diagnostic Summary Pertinent Ops Logs Pertinent Histories Performance--Heat Rate for Power Generation Root Cause Analysis Efforts Avoided Cost Benefits Marginal Equipment Tracking Component Monthly Maintenance Cost Monthly Availability Repair Schedule The Planning and Estimating Guide report is a particularly important part of CM program planning and management. Figure 5 gives an Excel spreadsheet example. 4

5 Figure 5. Planning and Estimating Guide example. A 1996 dollar is worth about $1.46 in We looked at one of these guides from the mid-1990 s and, using the inflated dollar value, found today s IR camera prices have decreased 70%, reporting software has decreased about 85%, and telescope lens cost has decreased about 60%. We increased the estimate for labor cost and added estimated annual IR camera calibration and maintenance costs. Training costs have decreased about 6% since the mid 90 s. The annual estimate avoided cost of $300,000 is based on electric power generation industry averages and, of course, may vary with facilities, applications, and program management. We did not inflate this value by 1.46 times for today s dollars, though it would be justified to do so. We believe this example report is very conservative and well within the capability of many IR Thermography CM programs. WHEN The E&CI matrix shown in Figure 1 also lends itself to help determine When. The number at the intersection of the diagnostic technology with the equipment item gives the number of months between surveys. The example is only partially filled in to keep it simple. For IR thermography and lube oil analysis, there is a 6 for 5

6 the first 4 items indicating these items should be surveyed every 6 months for this example. For vibration, it is every 4 months. The diagnostic technology survey frequency is driven by your facility and is a team decision. Survey frequency is a function of system load, facility cleanliness, equipment quality, and equipment history to name a few factors. Managers can use this list to estimate workload. One can determine how much time is required to perform, say, an IR survey on average for individual items. Together with annual IR survey frequency, one can estimate how much thermographer time is required to survey all items annually for scheduled IR surveys. In addition to routine diagnostic surveys such as IR thermography that can be scheduled with the routine preventive maintenance scheduling program, there are more diagnostic surveys to be considered. Let s focus on IR thermography. A thermographer should perform a baseline IR survey, especially for mechanical equipment. Pre-outage and post-outage IR surveys are also recommended. IR surveys of new equipment for acceptance testing as well as a follow-up IR survey on repaired equipment round out the list. In terms of when these surveys should be done, here s a suggested list: Routine the example shows every 6 months. Greater or less frequency depends on factors mentioned above. Adding these to your standard preventive maintenance schedule helps insure the diagnostic surveys are done. Baseline done once when everything is at greater than 50% load. Trending IR Thermography is a comparison technology. One can compare in the same image at the same time, typical for electrical applications. One can also compare the same component at different times, i.e. trend the data, especially useful for mechanical applications. New equipment on installation testing. Ensures no thermal anomalies and can be added to baseline report. Pre-Outage done in time to obtain necessary parts for repair during outage. Post-Outage done on startup when load is greater than 40% to 50%. Follow-up What if repair personnel fixed the wrong component, or didn t actually fix the right one? Some more comments on trending are warranted. For electrical applications, the thermographer is usually comparing phases with similar equipment under similar load in the same image at the same time. For mechanical applications, the thermographer is often interested in how a given component behaves over time. Now we re comparing the same item with itself over time trending. A baseline IR survey is very important for components that are evaluated primarily by trending such as many mechanical systems. This is not a blackand-white division as one often wishes to follow electrical thermal anomalies over time as well. And with some mechanical components, you don t need trending to see there s a problem. Figure 3 is an example. It cannot be overemphasized that routine diagnostic surveys need to be done on schedule. Condition monitoring is not a squeaky wheel. Often the same person that does the IR thermography surveys also does maintenance repair work. Equipment breakdown is a squeaky wheel and can lead to a situation where the IR surveys don t get done due to other higher priority repair work. This leads to more breakdowns since the CM surveys were not done. The thermographer gets trapped in a repair cycle and the CM program suffers. Good management allows the CM program to prosper, reducing the number of breakdown repairs resulting in a more efficient and effective maintenance program. WHERE For diagnostic surveys, where means routes and route planning. The E & CI matrix in Figure 1 also defines the where although it doesn t show the equipment location specifically. One must consider not just the equipment location, but also the diagnostician s location. Knowledge of these two factors is crucial for a good survey. Again, let s focus on IR thermography. Many thermographers have a great deal of experience in one application. For example an electrician/thermographer would know electrical applications and electrical equipment locations quite well for their own facility. But when performing IR assessment of mechanical components, this same thermographer would probably want to enlist the help of a mechanical technician who knows that type of equipment quite well. Also, a contract thermographer who may be skilled in many applications would need both electrical and mechanical help to perform a facility IR survey. And the facility usually wants a visitor to have an escort for safety reasons. Plus, only qualified personnel are authorized to open live electrical switchgear cabinets, etc. 6

7 This leads to an IR survey route comprising at least two routes, one electrical and one mechanical, often with different guides for each. A visual survey is part and parcel of any IR survey, and having a guide familiar with the equipment really enhances that portion of the assessment. Thermographer location is another important factor in where. In order to find problems, the thermographer needs to be close enough and have a line-of-sight view. For CM thermography, you are viewing the surface temperature, unless you re viewing through an IR window. Composing an IR image to document an anomaly is second nature to experienced thermographers, but isn t always obvious and needs to be learned. One needs to be close enough to identify the component and usually close enough to get a temperature measurement. But context is also important, especially for electrical applications. At least one other phase should be in the image, if possible, to allow direct comparison. For trending, the thermographer should view the equipment from the same spot every time. Paint a spot on the floor if permitted. Safety is of primary importance. For an electrical IR survey, everyone should abide by the NFPA 70E guidelines and local facility safety requirements. You must avoid both shock hazards and arc flash hazards. Figure 6 gives a brief overview of electric shock boundaries and the flash protection boundary. It shows the flash protection boundary outside the limited approach (shock) boundary, but that is not always the case. Note: The flash protection boundary is that distance from an arc flash source where the exposed person without PPE gets only second degree burns. Also, it doesn t address potential shrapnel, pressure waves and sound, just flash burns. Inside the arc flash boundary, proper PPE (Personal Protective Equipment) of the right category must be worn. Inside the limited approach boundary, unqualified personnel must be accompanied at all times by qualified personnel. Unqualified personnel are not allowed inside the restricted approach boundary. This is but a very brief overview. Do not do IR surveys on exposed live electrical equipment without first taking an appropriate electrical safety course and following the NFPA guidelines. Figure 6. NFPA approach limits. One reason IR windows are becoming so popular is they are much safe, easier, and faster than opening up cabinets to expose live switchgear. 7

8 WHO Figure 7 gives an organizational chart with generic roles and responsibilities for a Condition Monitoring program. The CM coordinator must have a passion for condition monitoring and must be in a position of responsibility to be able to get things done. For some electric utilities, the CM coordinator is at the Plant Manager level. In this example, the IR thermographer is an electrician as most of the IR survey work is electrical. The fact that this individual is qualified to open live electrical switchgear is a definite plus. Other CM technologies are covered by the mechanic for lube oil program management and vibration, and operation PTCs for acoustic/ultrasonic leak detection. Note: Nomenclature can drive one to distraction. CBM, Condition-Based Maintenance, is often used instead of CM. In some bailiwicks, CM stands for Corrective Maintenance and PM stands for Preventive Maintenance (scheduled maintenance). This organizational chart uses CorrM for Corrective Maintenance and CM for Condition Monitoring. Figure 7. Sample of a condition monitoring organizational chart. Team organization is crucial. Who gets what and when is one of the very important aspects of a good CM program. Flow charts are helpful in managing and organizing this hierarchy. Figure 8 is a sample flow chart showing how one electric utility company deals with CM data and information flow. 8

9 Figure 8. CM Data and Information Flow Chart example. Figure 9 is an example of a flow chart that helps set up the CM data acquisition. Note the flow chart in large part generates the E&CI matrix discussed under What and shown in Figure 1. Figure 9. CM Data setup flow chart example. Flow charts for setting priorities, scheduling repairs, doing the repair work and providing feedback are also useful, but too lengthy to discuss in this paper. 9

10 WHY The last W, why is illustrated in Figure 5 showing the annual estimated gross benefits of just the IR thermography program. A good CM program pays for itself and then some. Plus, safety and reliability are improved. For electric power utilities, all these factors are very important. Having worked with electric power utilities for over 25 years, we sometimes wish customers would have a greater appreciation for what the utilities do to ensure that when you turn on the TV, the microwave, the lights, the washer, the dryer, the air conditioner, and so on, they come on, or at least have electric power to them. But in a way, having customers assume the power is going to be there when they need it, is a real compliment to the utilities. You like being so good, you re taken for granted. SUMMARY If your company, or the companies with which you work, want to lower their maintenance costs, improve reliability and safety, and optimize maintenance overall, a good Condition Monitoring program will be very useful to them. Many companies already have some these elements, but to really make a difference, they need to develop an organized approach. As demonstrated in this paper, the 5 W s provide a good foundation for building a successful CM program. ACKNOWLEDGEMENTS The authors are very grateful to the Infrared Training Center (ITC) and FLIR Systems, Inc. for their support in writing this manuscript. BIOGRAPHICAL SKETCH Bob holds a Ph.D. in Physics from the University of Wisconsin-Madison. He began the first infrared thermography seminar at the University of Wisconsin Extension in He co-founded the Thermosense Conference in 1978 with two other colleagues from the UW. He has presented and published numerous technical papers on infrared thermography applications, as well as contributing chapters to textbooks such as Applied Thermal Design and the Encyclopedia of Optical Engineering. In 2000, he founded the InfraMation Conference, the largest commercial IR thermography applications conference. Bob has over 35 years of experience in infrared thermography applications and training. With several years of practical experience at a large electric utility and at a large aerospace defense company, Dr. Madding has a unique combination of both technical product and applications knowledge and a school of hard knocks understanding of IR thermographer issues. While at Maintenance and Diagnostics, an EPRI contractor, he developed advanced applications of IR thermography for condition monitoring of power plants, substations, and switchyards. While Director of the Infrared Training Center, Bob taught classes, developed training course materials for all the ITC course offerings, wrote software for electrical load correction of hot spot temperature rise, created a power loss calculator that estimates electrical resistance on problematic operating equipment such as oil-filled circuit breakers, and developed other IR applications software to make the professional thermographers life more rewarding. Currently, Bob is President of RPM Energy Associates, LLC doing infrared imaging consulting work. 10