Archive | 1997

314

12:57 am
March 2, 1997
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Qualify and Certify Staff for Shaft Alignment

Companies should determine the skill level of personnel responsible for alignment, arrange for appropriate training for proficiency, and use qualification testing for certification.These examples show the need for certification in shaft alignment.

A maintenance technician at a chemical plant was asked to align a motor and a pump with a newly purchased laser shaft alignment system. Shaft position measurements were captured with the instrument. Corrections required to align the motor (assigned as the movable machine) with the pump indicated that the outboard end of the motor had to be lowered 85 mils and the inboard end of the motor had to be lowered 37 mils; there was no shim stock under the motor feet. After completely removing the motor, the technician began grinding away the baseplate. The motor was placed back on the base and shaft position measurements were captured again. Because too much metal had been ground away, the technician then added shims under the motor feet. Several side-to-side moves were made to bring the equipment into alignment.

A manufacturer of gas turbines was installing several large air compressors to expand the capacity of a system used to test jet engines. Requests for bids to install the 11,000 hp motors, gearboxes, and compressors were sent to several general contractors. Detailed specifications including instructions for installing foundations and sole plates and for correcting soft foot conditions were provided, along with rough alignment procedures and final hot and cold alignment procedures. The general contractor was told to subcontract the alignment work to companies specializing in machinery alignment. The specifications were sent to the subcontractors; however, several of the contractors submitted bids although they did not understand many of the detailed specifications. Toward the end of the project, the company discovered that the alignment work was not performed to the written specifications and payment was withheld from the contractors who performed the work.

A company that was in the process of becoming ISO 9000, 9001, and 9002 compliant requested information on certification testing for maintenance personnel who perform shaft alignment. Several employees had been certified in vibration analysis and thermography. The company wanted documentation that personnel were adept at finding and fixing problems.

A petroleum company decided to sell one of its facilities. Several prospective buyers were interested in retaining as many employees as possible. However, they wanted to retain only people who were adequately trained and were certified to do specific tasks. When asked to provide information on task certification of its employees, the petroleum company was unable to do so.

A steel company was having problems with a fairly complex multiple-element drive train. Misalignment was found to be the root cause of the failures. No one in the plant knew how to align the drive system. An alignment service company was contacted; although a technician said he could align the drive system in less than 4 hours, the job actually took several days to complete.

An electric utility company experienced several failures on a critical pump. Inhouse maintenance personnel had been using a laser shaft alignment system to measure the positions of the shafts. The pump was being driven by a variable speed hydraulic clutch. In the instruction manual, the clutch manufacturer stated that the clutch would rise upward 15 mils once it attained normal operating conditions. Maintenance personnel set the clutch 15 mils lower than the pump shaft assuming that the pump would not move from off-line to running conditions. A survey showed that the pump shaft rose upward far more than the clutch did, forcing the unit to run under severe misalignment conditions.

Equipment for vibration analysis and infrared thermography has improved dramatically over the past 20 years, and the number of people working in these areas has increased substantially. With a small investment, anyone can buy a personal computer and a vibration data collector or an infrared camera and be in business. However, the learning curve for this equipment is long and steep.

Over the past 5 years, there has been an effort to determine the skill level of people working in vibration analysis and infrared thermography through qualification and certification testing by several companies and institutions. Many companies are requiring their employees to become certified.

Certification for other tasks in the workplace such as correcting rotating machinery problems including balancing, shaft alignment, and tribology also has been discussed. With certification testing comes questions. Who has the authority to provide certification? What is the best way to determine if people are qualified to perform shaft alignment? How can trainees prove what they learn from training courses? And how qualified are contractors who are installing new rotating machinery?

Who to train and qualify
Many organizations feel that the responsibility for shaft alignment rests solely in the hands of tradespeople (mechanics, millwrights, pipefitters, and electricians). However, are tradespeople responsible for the following tasks?

  • Selecting training courses they feel they need and for sending themselves to the courses
  • Researching types of shaft alignment measurement systems and purchasing a system that best fits the needs of their organization
  • Telling a contractor that he is not installing rotating machinery correctly
  • Hiring staff or contractors to help with the work overload
  • Rebuilding a piece of rotating machinery that is malfunctioning because of excessive runout conditions
  • Determining that a rotating machinery foundation or baseplate that has been removed and reinstalled has deteriorated excessively or been installed improperly
  • Redesigning and reworking improperly installed piping that is putting excessive strain on the rotating machinery it is attached to
  • Purchasing and installing piping supports, or designing a custom piping anchor on a CAD system, purchasing the materials, and installing the anchor
  • Selecting a new flexible coupling design to replace one that fails often or does not work well
  • Picking a pump as the movable machine and leaving the motor as the stationary machine
  • Issuing work orders to check the alignment of all the rotating machinery every year
  • Shutting a machine down on the basis of vibration and temperature data that indicate a misalignment or soft foot condition
  • Determining which machinery might require a hot alignment check, selecting an off-line-to-running machinery movement measurement technique, installing the equipment on the machinery, measuring and analyzing data, and altering the cold alignment position on the basis of data collected
  • Maintaining records of alignment work performed and saving records in the equipment files or a computer database
  • Installing X-Y proximity probes on a machine supported in sliding type bearings to analyze the Lissajous orbit for signs of running misalignment.

Shaft alignment training should be mandatory for managers, engineers, technicians, front-line supervisors, and tradespeople to provide them with the minimum working knowledge needed to achieve accurate alignment and to know the process. Engineering and maintenance managers, rotating equipment and maintenance engineers, maintenance technicians, vibration specialists, foremen, and front-line supervisors, as well as the trades personnel, all should be trained and qualified to do their respective tasks.

Assessing and verifying knowledge and experience
Before qualification testing begins, shaft alignment knowledge can be assessed using a Field Experience Evaluation form that queries employees’ or contractors’ knowledge and experience on specific types of machinery. Individuals can then be tested on specific tasks to determine if they are capable or if they need supplementary training to raise the level of proficiency.

The form can be used to determine required training for personnel installing, maintaining, or aligning rotating machinery. But how can experience and proficiency be verified?

Written or oral examinations can verify the knowledge level for each item in the form. One comprehensive test might encompass every facet of shaft alignment, or a series of tests can be given for discrete blocks of information. If the overall body of information is broken down into separate blocks, personnel with little or no experience can be tested incrementally as their level of knowledge grows. The accompanying section, “Test Requirements for Alignment Knowledge Assessment,” outlines possible test subjects.

Written or oral exams can test knowledge but are inadequate to determine skill level in performing specific tasks. Perhaps the most effective means to verify knowledge and skill level is to have employees perform tasks on a simulator or directly on an operating rotating equipment drive system. However, using process machinery as a test platform may not be possible. Having simulation equipment available allows testing to occur at any time without affecting production or maintenance schedules. For accurate skills assessment, test equipment must simulate real life circumstances.

Qualification and certification testing in tasks such as vibration analysis, thermography, and shaft alignment is necessary. Establishing the requirements for qualification or certification can be accomplished by appraising the experience level of personnel through an evaluation form that addresses all aspects of the task. Skills of each individual can then be assessed and appropriate training can be administered. Written or oral exams and task simulation tests can be conducted to determine the true proficiency of personnel. MT


John Piotrowski is president of Turvac Inc., an alignment training and consulting company, 125 Settlemyre Rd., Oregonia, OH 45054; (513) 932-2771; e-mail turvac@your-net.com; Internet http://www.ncinter.net/~turvac/. He is the author of Shaft Alignment Handbook.

TEST REQUIREMENTS FOR ALIGNMENT KNOWLEDGE ASSESSMENT

Basic test

  • Consequences of poor alignment on rotating machinery
  • Detecting misalignment on running rotating machinery (vibration, infrared methods)
  • Use and care of measuring tools and instruments (feeler gauges, dial indicators, optical encoders, proximity probes, laser/detector system, etc.)
  • Finding and correcting excessive runout conditions
  • Finding and correcting soft foot
  • Finding and correcting excessive piping strain
  • Foundation and baseplate design, installation, and care
  • Concrete and grouting installation
  • Alignment tolerances
  • Rigid and flexible coupling design, installation, and care
  • How to perform the reverse indicator method
  • Basic mathematical or graphical/modeling principles for realignment
  • How to determine effective alignment corrections using the reverse indicator technique
  • Keeping records of alignment work.

Intermediate test

  • How to perform the face and rim method
  • How to determine effective alignment corrections using the face and rim technique
  • How to perform the shaft to coupling spool method
  • How to determine effective alignment corrections using the shaft to coupling spool technique
  • How to perform the double radial method
  • How to determine effective alignment corrections using the double radial technique
  • How to perform the face-face method
  • How to determine effective alignment corrections using the face-face technique
  • Mathematical or graphical/modeling principles for all of the methods listed.

Advanced test

  • How to align multiple-element drive trains
  • How to align right angle drives
  • The four categories for measuring OL2R machinery movement
  • Calculating machine case thermal expansion
  • Inside micrometer-tooling ball-angle measurement methods
  • Proximity probes with water cooled stands technique
  • Using optical alignment tooling for OL2R machinery movement
  • Alignment bars with proximity probes OL2R method
  • Using laser-detector systems to measure OL2R machinery movement
  • Using the ball-rod-tubing connector system to measure OL2R machinery movement
  • Using the vernier-strobe system to measure OL2R machinery movement
  • Mathematical or graphical/modeling principles for all of the methods listed
  • How to align rotating machinery to compensate for OL2R machinery movement.

 

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1198

12:52 am
March 2, 1997
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Using Ultrasound for High Voltage Insulation Testing

Ultrasound is an effective, low cost method for evaluating the condition of insulation components on high-voltage transmission and distribution equipment. Conventional testing methods require the equipment to be shut down. Ultrasonic testing can locate failing insulation components in live electrical distribution and transmission equipment.

Ultrasonic testing is suitable for outdoor substation and aerial transmission equipment, particularly when coupled with a parabolic concentrator. Enclosed switchgear equipment also can be tested. Spectrum analysis of the ultrasound signal allows tracking to be distinguished from other sources of ultrasound in the gear or adjacent areas. Listening ports permit the safe inspection of any type of switchgear.

Overhead transmission lines
The night shift electrical supervisor at a petrochemical refinery received reports of visible arcing at porcelain insulators on a 69 kV power pole. The power line supplied a wastewater treatment facility. If the facility lost power, the refinery would be unable to operate.

From the symptoms described by the supervisor, it was likely that an insulator was failing. The failure of insulators on high-voltage (greater than 4 kV) power transmission and distribution equipment can often result in electrons discharging into the air, a phenomenon known as tracking, corona, or partial discharge. Under the right conditions, the discharge can find a path to ground, resulting in a highly destructive ground fault.

The electrical supervisor wanted to know if a recent infrared test had identified any problems at these insulators. He also wanted to know if the problems had disappeared, because arcing could no longer be seen. The supervisor was told that, except for severe cases where a current path to ground was established, infrared testing would not detect high-voltage insulator failures because the corona or tracking typically produces little or no heat. He also was informed that this situation might be extremely dangerous and that it warranted immediate attention.

A UE Systems Ultraprobe 2000 was used to evaluate the problem. The instrument hears ultrasound (sound above 20,000 Hz) and converts it to audible frequencies. High-voltage discharges that accompany the breakdown of insulation cause ionization of the air and the ionization produces ultrasound. Thus, the presence of tracking or corona can be readily detected by an ultrasonic instrument.

The instrument is simply pointed at the area of concern. If tracking or corona is present, a buzzing noise similar to static on a radio is heard through the instrument headphones. The instrument is directional, allowing the location of the insulation fault to be determined by listening from several locations until the high sound source is pinpointed.

Power pole insulators at the refinery were located about 60 ft above ground. In addition, the area around the pole had discharging steam traps and several compressed air leaks. The traps and air leaks produced high levels of background ultrasound that would ordinarily overpower the ultrasound produced by insulator failure. A parabolic concentrator was used to overcome these problems. This device has a seven element ultrasonic detector array mounted in the center of a parabolic dish. The dish features an optical sight that expedites pinpointing the source of ultrasound.

The concentrator provides two advantages:

  • Instrument sensitivity is more than doubled. As a result, even low-level discharges occurring at a substantial distance can be detected.
  • The concentrator is extremely directional. Adjacent ultrasound sources are rejected and the precise source of ultrasound is easily determined.

The ultrasound instrument immediately indicated that corona discharge was occurring at each of the insulators. The C phase insulator had a very high level of discharge.

In addition, the insulators were checked with an infrared imager using a 3x telescope. The imager revealed a ring of heat on each insulator. The ring of heat was about 2 deg F above adjacent surfaces and it occurred at a different location on each insulator. There were no connections near any of the rings. It was determined that the heating probably corresponded to the location of the discharge at each insulator. Temperature differences were very small and could be overlooked easily during a typical infrared survey.

When both ultrasound and heat are detected from a failing insulator, the problem has reached a potentially dangerous stage and requires immediate shutdown. The presence of heat indicates a current flow to ground. This flow will precede catastrophic failure.

Although the insulators were subjected to periodic inspections and cleaning, they obviously were failing. Backup generators were brought in to power the facility while the insulators were replaced.

Enclosed switchgear
A combination of infrared and ultrasonic testing is often used on high-voltage electrical equipment, particularly enclosed switchgear. Infrared equipment can locate resistive faults such as dirty switch contacts or loose joints. The ultrasonic instrument locates developing insulation faults. In enclosed gear, tracking is a particularly serious problem because the distance from current carrying components to ground is usually small. Failure of insulating components can cause switchgear components to vaporize. Ultrasonic testing in enclosed switchgear may be more important than infrared testing.

At a multi-use 1 million sq ft facility, access doors to a 13 kV switch were locked and no keys were available. The internal current carrying components could not be inspected. This switch was critical; its loss would shut down the entire complex.

Because ultrasonic sound can pass through small cracks at doors or through ventilation openings, an ultrasonic test was performed. The test revealed extremely high internal ionization. Bolt cutters were used to remove the locks. With the lights out, arcing was visible where the bus passed through a supporting barrier board.

Infrared testing also revealed a track of heat leading directly to a support bolt, indicating that current was already flowing to ground. Building tenants were notified and an orderly shutdown was conducted the next evening to correct the problem. The complex was back on line the following morning.

Often, when enclosed high-voltage switchgear or transformers are inspected, it is difficult to distinguish between ultrasound produced by insulation failure and ultrasound produced by vibration of mechanical components. However, spectral analysis of the ultrasound signal can be used to distinguish tracking and corona from mechanically produced ultrasound.

Output from the ultrasound instrument is fed into a spectrum analyzer. The spectrum analyzer can be the same portable data logger used for monitoring vibration in mechanical equipment. Mechanical vibration produces a spectrum in multiples of 60 Hz (electrical field frequency). Tracking and corona ultrasound results from ionization of air. This process produces broadband noise. There may be a 60 Hz component because the arc will rise and collapse with the voltage cycle. However, distinct 60 Hz multiples are not present.

Mechanical vibration produces an easily discerned spectral pattern while tracking or corona produces a noise pattern. Thus, for example, spectral readings can be taken at a dry-type transformer to determine whether an insulation fault is developing. Alternatively, the spectral readings can distinguish between potential transformer or switchgear case vibration and tracking.

On many types of enclosed high-voltage gear, front or rear panels can be removed to provide access for ultrasonic testing. (All appropriate safety procedures must be observed during removal of panels on energized high-voltage switchgear. See National Fire Protection Association 70E, “Standard for Electrical Safety Requirements for Employee Workplaces.”)

However, high-voltage switchgear is often totally enclosed. Access is through interlocked doors that cannot be opened when the gear is energized. This type of gear can be easily tested for insulation breakdown through the use of a listening port.

Ultrasound easily passes through an opening but is readily blocked by a solid surface. On switchgear, a listening port can often be provided by removing a few bolts from the housing. The ultrasonic instrument is then held near the open bolt holes to detect the distinctive buzz of internal tracking or corona. On totally sealed gear, a 4 in. dia capped hole can be cut into the switchgear housing during an outage. The port cover can be removed for inspection. The ultrasonic instrument is then positioned at the hole and operated to detect any internal tracking. MT

Information supplied by Mid Atlantic Infrared Services, Inc., Bethesda, MD; (301) 320-2870. Continue Reading →

933

1:57 am
February 2, 1997
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Managing Preventive Maintenance

Excerpt from Joel Levitt’s book, Managing Factory Maintenance, explains how to justify a preventive maintenance program and provides insight into how to set up a program.

What is preventive maintenance (PM)? It is a series of tasks that either

  1. Extends the life of an asset (greasing a gearbox, for example) or
  2. Detects that an asset has had critical wear and is going to fail or break down (quarterly inspection of a pump seal).

These tasks are assembled into lists. Each task is marked off when it is completed. There should always be room on the bottom or side of the task list to note comments. Actionable items should be highlighted.

These tasks should be directed at how the asset will fail. The rule is that the tasks should repair the unit’s most expensive, most likely, or most dangerous failure modes. Caveat: There will still be failures and breakdown even with the best PM systems. Your goal is to reduce the breakdowns to minuscule levels and convert the breakdowns that are left into learning experiences to improve your delivery of maintenance service.

PM systems also include

  1. Maintaining a record keeping system to track PM, failures, and equipment utilization. Creating baselines for other analysis activity.
  2. All types of predictive activities, including inspection, taking measurements, inspecting parts for quality, and analyzing oil, temperature, and vibration. Recording all data from predictive activity for trend analysis.
  3. Short or minor repairs up to 30 minutes in length. This activity is a great boost to productivity because no additional travel time is required.
  4. Writing up conditions that require attention (conditions that will lead or potentially lead to a failure). Writeups of machine condition.
  5. Scheduling and actually doing repairs written up by PM inspectors.
  6. Using the frequency and severity of failures to refine the PM task list.
  7. Continual training and upgrading of inspectors’ skills, improvements to PM technology.

One point that is commonly missed is that PM is a way station to the ultimate goal of maintainability improvement. PM can be an expensive option because it requires constant inputs of labor, materials, and downtime. The ultimate goal of maintenance is high reliability without the inputs.

Some benefits of a PM system
Your inspectors are your eyes and ears into the condition of your equipment. You can use their information on decisions to change your equipment makeup, change specifications, or increase availability.

Equipment has a breakdown curve; once over the threshold, failures increase rapidly and unpredictably. Working lower on the curve adds predictability and reliability.

Early detection prevents core damage and gives you more time to plan and secure parts and specialized tools.

Predictability shifts the maintenance workload from emergency fire fighting due to random failures to a more orderly scheduled maintenance system.

The frequency of user-detected failures will decrease as inspectors catch more and more of the problems. Decreased user problems translates to increased satisfaction.

Cost justification for PM
One way to sell PM is to discuss the effect of downtime from breakdowns. Breakdowns can be a strong selling point when we develop data on the costs.

Accumulate your average number of breakdowns per year and compare 70 percent of that cost to the cost of inspections, adjustment, cleaning, bolting, lubrication, short repairs, and corrective maintenance. We assume that 70 percent of your breakdowns will be eliminated through an average quality PM system. The following formula should be true to go ahead with a PM system:

(Number of breakdowns x average cost per breakdown x 70 percent) > cost of PM system.

Management needs to see the longer view on the nature of proper maintenance that only you can show. Sometimes, at trade conventions or meetings, managers hear that PM is hot this year and they use this enthusiasm to help get a program approved or upgraded. Be conservative in your return on investment estimate and liberal on the amount of funds it will take.

The benefits possible from a PM program are real. Getting the benefit of the installation of a PM system requires a commitment to the elements of a successful system. To maximize the return on investment in your equipment, technicians must keep equipment in peak operating condition.

The PM approach is the long-term approach. Anything less than peak operating condition results in increased operating, maintenance, ownership, or downtime costs. These costs vary slowly. Low overall costs of operation are the result of years of good maintenance policy.

Anyone can reduce maintenance costs for a few quarters by cutting back on PM inspections and associated repairs. The temptation to cut back is sometimes great because the piper gets paid 1 to 2 years down the road.

Because of the temptation and the length of time to get a return on the investment, most organizations have either no PM system or only a partial PM system. Some organizations inspect, lubricate, and adjust but don’t feed back repairs to be scheduled unless there are clear and present dangers. Other organizations use fixed PM task lists with fixed frequencies without any review of failure, histories, or service.

Selling PM to management
The first step is to determine the cost of operating in your current mode. The second step is to prove through rigorous modeling that savings or significant improvement to service will result from the proposed improvement.

When possible, include other departments such as production, accounting, or even marketing to help prepare your arguments. Good maintenance effort affects every part of the plant, so every part of the plant has candidates to contribute in your discussions. Marketing is often a good choice because good maintenance will help them with the customers by ensuring delivery dates and maintaining quality.

The end customer is sometimes the strongest voice for PM. All new vendors to General Motors are subject to a plant audit. One of the elements of the audit is the existence of a PM system (that seems to work). They don’t want to put their production in the hands of an organization that uses haphazard maintenance practices.

In some cases maintenance costs increase while overall costs decrease. The offset comes from decreased downtime, improved customer service, or other areas.

We are in an extremely competitive battle for the organization’s investment dollars. Investments in maintenance can earn big returns. We must sell our strong suits, which are cost avoidance, improved customer satisfaction, and reduced downtime. Use the language (and issues) of your organization to sell a PM program. In every organization some issues are more important than any others. The benefits of PM are summarized in the section “Benefits of a PM System: The Stakeholders’ Priorities.”

Steps for installing a PM system

1. Set up the PM task force. The PM task force should include craftspeople (I prefer to include the shop steward in union environments or another opinion leader), one or two staff people (particularly an old timer who has seen everything), and someone from data processing (if you are computerizing at this point). In a modern production facility members of production and production control should be involved on some basis.

2. Analyze the needs and concerns of the maintenance stakeholders. Look at each group and see how they contribute to the success of the organization. Determine who is affected by changes in maintenance. The stakeholders should include at least production, production control, stores, plant manager, top management, purchasing, accounting, housekeeping, maintenance craftspeople, maintenance staff (supervisors, planners, clerks), and even outside vendors. Remember each stakeholder group must be sold individually. Each one has different needs, concerns, fears, and prejudices.

3. Provide the task force with available resources (people/skills/hours), the required demands (zero-based budget documents), and an analysis of the replacement cost of the asset being supported. The value of the productive output and its associated factory cost also is useful.

4. Have the task force set goals from the system. Objectives are set. At this early point consider training for members of the task force in computer skills (if you plan on computerizing) like typing, Windows, word processors, and spreadsheets. Create daily situations in which the newly trained people have to interact with the computer, such as using the word processor or developing spreadsheet templates. This practice is essential at the early point because you want the task force members to have expertise with computers before computerization of maintenance. Also consider putting in a manual work order system at this point (if you don’t have one).

5. After the goals are set, pick a name for the effort. I suggest you stay away from PM system as a name because it has negative connotations for nonmaintenance professionals. Some good names might include PIE (Profit Improvement Effort), DEEP (Downtime Elimination and Education Effort), or QIP (Quality Improvement Effort). The name should reflect the goals.

6. Prepare a preliminary budget for the project and divide the numbers into setup and ongoing.

Setup budget items

  • Modernization of equipment to PM standard (capital costs)
  • Pay for system to store information
  • Labor for data collection, data entry
  • Labor to train inspectors
  • Labor for task force meetings, losses on shop floor
  • Labor to set up task lists, frequencies, standards
  • Purchase of any predictive maintenance devices
  • Labor to train all mechanics in entry and use of system.

Ongoing budget items

  • Labor to carry out PM task lists, short repairs
  • Parts costs for task lists, planned component replacement
  • Additional investments in predictive technology
  • Funds to carry out writeups (corrective maintenance tasks that will maintain a higher standard of maintenance).

7. Sell the PM project to all stakeholders, focusing on their needs, concerns, and fears. When approval or sign-off is given, continue to the next steps. If approval is withheld, retrace your steps and reanalyze.

8. Inventory and tag all equipment to be considered for PM. Compile a list of all of the assets (or units) that you are responsible for. If no list exists, start the process with the accounting asset list. This list is a starting point; beware of assets too old and fully depreciated on the accounting list because these assets are the biggest maintenance consumers. The accounting list will aggregate all building systems under “building” rather than breaking them out to electrical distribution system, compressed air piping, etc.

The list should include the following:

  • Asset number, brass tag number, or unit number. It should be a unique number.
  • Make and model of the equipment, if relevant.
  • Serial number, basic specifications, and capacities.
  • Physical location.
  • Financial location (where to charge)–department, area of responsibility.
  • Subcomponents of the asset. Include high cost items, especially if they require special skills to support.

 

9. Select a system to store information about equipment and select forms for PM-generated work orders and check-off sheets. Design first draft of performance reports, to be revised later, that audit the PM system.

10. Draft a standard operating procedure (SOP) for the PM system. This document will be revised many times before the first year is up. Begin training in the SOPs with the rest of the crew.

11. Task force members or other people from the shop and staff complete data entry or preparation of equipment record cards. Rotate this job so many people have experience. Make sure the SOP truly reflects how to enter new assets (modify as required).

12. Consider temporary workers to replace the task force’s hours on the shop floor (and to replace anyone who is rotated through the data entry position). Take this opportunity to build critical mass in knowledge of your system by having your people do the data entry.

13. Conduct daily audits of data typed into the system. Verify the previous day’s entries against the source document or (even better) against the nameplate information on the machine. Rotate the audit job with the data entry job.

14. Select and train people to be inspectors. Allow their input into the next steps. Consider using inspectors to help set up the specifics of the system. Include training in root cause analysis.

15. Determine which units will be under PM and which units will be B’n’F (Bust’n’fix). Remember that there is a real cost associated with including any item in the PM program. If, for example, you spend time on PM tasks for inappropriate equipment, you will not have time for the essential equipment. Costs to include in a PM program:

Cost of inclusion = cost per PM x number of PM tasks per year.

To decide which units to include in the PM system, apply the principles outlined in the section “Rules for Inclusion of Equipment in a PM System.”

16. Schedule modernization on units requiring it. Plan to retire bad units if possible. Bad units that are not fixed present big problems for PM systems. It may be better to leave bad units off the system. A bad unit on the system will numb and demoralize the inspectors because they are asked to not see the problems when it comes up for PM because nothing is done between inspections.

17. Select which PM clocks you will use (days, utilization, energy, add-oil). A clock is designed to indicate wear on a system or asset. Using the number of days elapsed (every 30 days, 90 days, 1 year) is good for assets in regular use. A compressor used irregularly might respond better to run-time hours (PM every 500 hours). A concrete plant might use yards of product (PM every 10,000 yards); a steel mill might use tons of steel.

18. Decide what predictive maintenance technologies you will use. Train inspectors in techniques. Even better, provide the information to the inspectors or to the task force and let them pick the modalities.

19. Set up task lists for different levels of PM and different classes. Factor in your specific operating conditions, skill levels, operator experience, etc. Consider unit based, string based, future benefit based, and both interruptive and noninterruptive techniques. Consider a pilot program on a piece of critical equipment. Build your support through publicizing your successes.

20. Be sure inspectors are well equipped for their jobs. They need the following:

  • Actual task list with space for readings, reports, observations. Task list should include specifications for the completion of the tasks and individualized drawings if indicated.
  • Equipment manual, access to unit history files. Inspectors or operators should be encouraged to look through and familiarize themselves with the manuals.
  • Standard tools and materials for short repairs. Operators should be given the exact tools needed for the PM or cleaning (10 mm wrench, 4 mm allen wrench, etc.). A cart designed for most short repairs (with tools and commonly needed materials) can significantly improve productivity of the mechanics.
  • Any specialized tools or gauges to perform inspection.
  • Standardized PM parts kits, lubricants, cleaning supplies.
  • Log sheets to write up short repairs.
  • Forms to write up longer jobs.

21. Assign work standards to the task lists for scheduling purposes. Observe some jobs to get an idea of the time.

22. Engineer the PM tasks. Look at the tasks through the eyes of an industrial engineer. Try to simplify, eliminate, speed up each task. Improve the tooling and ergonomics of each task.

23. Determine frequencies for the task lists (based on the clocks chosen earlier). Select parameters for the different task lists.

24. Implement system, load schedule, and balance hours. Be sure you predict when the PM hours are going to be needed and balance these needs to the crew availability. Schedule December and August very lightly. Allow catchup times.

Managing Factory Maintenance (ISBN 0-8311-3063-6), published by Industrial Press Inc., New York, provides considerably more information on preventive maintenance than is contained in this brief excerpt. The book also covers most every aspect of maintenance management, including maintenance department evaluation, communication and delegation, zero-base budgeting, predictive maintenance, total productive maintenance, managing maintenance with a computerized maintenance management system, planning and scheduling techniques, time management, and supervisor evaluation. To purchase a copy of the book, contact Industrial Press by telephone, (212) 889-6330, or on the Internet, www.industrialpress.com, or your book seller. MT


Joel Levitt is president of Springfield Resources, a maintenance consulting and training company in Philadelphia, PA; (800) 242-5656; e-mail jlevitt@worldnet.att.net. He also has produced a set of audio tapes and a workbook that can be used with the book for self-study or education of plant personnel. He has published additional articles on his Internet site at www.maintrainer.com.

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276

8:24 pm
February 1, 1997
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Setting Up a Condition Management Program

Computerized plant condition management systems outperform manual methods in the enhancement of safety and the reliability of equipment and piping. Accurate treatment of inspection data can cut inspection monitoring costs.

Regulatory requirements and industry codes and practices, combined with an international drive for more cost-effective preventive maintenance, are leading many plants toward computerized information management systems to help organize and prioritize maintenance activity.

This shift coincides with a movement toward a risk-based approach to plant condition management that ranks units or individual equipment according to criticality or risk, allowing inspection efforts to be focused where they can have the greatest effect in risk reduction. There are a number of points to bear in mind when planning to implement a plant condition management system.

Data analysis software systems are now used in many refineries, chemical plants, and production facilities for the management of inspection information on piping, pressure vessels, and other equipment. These systems provide the economic tools to budget and plan long-term maintenance strategies, and they increase the ability to identify a problem before failure actually occurs. Inspections then lead to cost reductions.

Linking risk assessment to an information management system focuses inspection and preventive maintenance resources on high-risk areas where problems are most likely to occur. Equipment such as ultrasonic dataloggers cut costs by reducing the required inspection labor, reducing the required data entry, and eliminating the need for manual calculation of corrosion rates and remaining life predictions.

Plant piping and vessel condition management programs help answer a number of key questions:

  • How can the safety of operating personnel, the general public, and property be assured?
  • What engineering and metallurgical concerns need to be addressed?
  • What equipment, piping, and appurtenances require maintenance attention, replacement, or monitoring?
  • How should we prioritize this maintenance?
  • What is the remaining useful life of each piece of equipment?
  • How much inspection is required for each type of process or service?
  • What are the most efficient and cost-effective methods to achieve these goals?
  • What is the repair, alteration, and inspection history of piping and equipment?
  • How can records be updated to reflect the rapid changes in design and layout?

The issues that must be addressed when implementing any piping and pressure vessel condition management process were identified at a recent PCMS Users Conference. A number of those observations are outlined in the following sections.

Understand the objectives and software
Setting objectives was identified as the first implementation step. This step calls for the development of a comprehensive understanding of the compliance requirements for the applicable codes. Each plant must develop a specific mission statement for its program, wherein the expected improvements in plant reliability are clearly stated and then evaluated to meet the constraints of existing resources. Such resources include manpower availability and overall budget allowances. This step clarifies for the entire management team that project completion is a long-term goal that must be continually revisited and re-evaluated.


INSPECTION METHODS FOR INSULATED PIPING SYSTEMS
Uninsulated piping can be inspected by straight beam or L-wave ultrasonic techniques to gauge pipe thickness. Instruments with datalogging capabilities can be used to collect and store data for electronic download directly into the information management system. The detection of corrosion under insulation presents a challenge.

Insulation removal
The most effective method for inspecting insulated piping for corrosion is to remove the insulation, check the surface condition of the pipe, and replace the insulation. This approach will detect corrosion-induced stress corrosion cracking (CISCC) on stainless steels and may require eddy current, field metalography, or liquid penetrant inspection. This method is the most expensive method in terms of cost and time lost. The logistics of insulation removal will probably involve asbestos and its attendant complications. Process-related problems may occur if the insulation is removed while the piping is in service.

Ultrasonic thickness
Ultrasonic thickness measurement taken through inspection holes cut in the insulation is an effective inspection method but it is limited to a small area. It is expensive to cut the inspection holes and cover them with caps or covers. It is not practical to cut enough holes to get a reliable result. Inspection holes cut in the insulation may compromise the integrity of the insulation and add to the corrosion-under-insulation problem if they are not re-covered carefully. This technique will not detect CISCC on stainless steels.

Profile radiography
Profile radiography provides an x-ray type photograph of a small section of the pipe wall. The exposure source is usually iridium 19, or cobalt 60 for heavier wall pipe. A comparator block is included in the picture to determine the blowout factor for the exposure in order to calculate the remaining wall thickness of the pipe. Profile radiography is an effective evaluation method, but it becomes technically challenging in piping systems over 10 in. in diameter and offers the luxury of verifying only relatively small areas. This technique will not detect CISCC on stainless steels. In addition, radiation safety is a concern. Plant personnel cannot work within the area while the inspection is under way, which can result in downtime and manpower scheduling conflicts.

Real-time radiography
Real-time radiography (RTR) or fluoroscopy provides a clear view of the pipe’s outside diameter through the insulation, producing a silhouette of the pipe’s outside diameter on a television-type monitor that is viewed during the inspection. No film is used or developed. The real-time device has a source and image intensifier and detector connected to a C-arm. There are two major categories of RTR devices: one using an x-ray source and one using a radioactive source. Each has advantages and limitations; however, the x-ray systems deliver far better resolution than the isotope type equipment.


It is important to understand the software features that assist with data analysis. To operate an effective program from a limited budget, it is vital to distinguish among information required to operate the system, supplementary information that maximizes the analytical ability of the system, and truly optional information. Optional information adds value, but it can be added later, after the first round of implementation.

Develop an implementation plan
The next step is developing an implementation plan. Because costs of data entry, record organization, quality assurance checks on historical data, and program related inspections by far outweigh the costs of the software, a well planned implementation approach can deliver considerable savings. This step includes decisions on how much of the plant will be included in the initial implementation: the entire plant or perhaps only selected units or critical areas first.

Existing historical data from paper files, spreadsheets, process and instrumentation drawings, and isometric drawings should be carefully evaluated to decide what information is pertinent for transfer to the new software. Then the quality of this historical data must be evaluated. Obviously inaccurate thickness readings will distort the calculations for corrosion rates and remaining life. User experience shows that failure to check these data leads to problems following implementation, such as incorrect pipe sizes and schedules and thickness readings, which slow the program and increases costs.

Data entry methods must be considered. Although data always can be entered at the program screens, software that allows mass data entry from spreadsheets and dataloggers enhances the process. It may be necessary to gather data immediately to populate or enhance the database. The users group recommends the development and immediate documentation of guidelines for gathering thickness data. The guidelines should cover where to place thickness monitoring locations (TML), how to find TMLs in the field, and how the thickness readings should be taken. Over half of the users developed their own guidelines.

With the implementation plan in place it is possible to estimate the labor resources (internal, external, or both) needed to staff the project. Users report considerable success through a joint steering committee composed of plant personnel and representatives of the inspection company contracted to gather data. Used correctly, the steering committee keeps the relationship fresh, encourages change, and helps address problems in their infancy. Whether a steering committee or an individual, someone must be assigned responsibility to drive the project. Experience demonstrates that piecemeal planning will not work.

Field operations
The following information can help with planning, implementation, and operation of the plant condition management process.

  • Check quality of historical data. This task is tedious and exasperating but it is a key part of the operation. Plant personnel often find ingenious uses and filing systems for key data such as UW 1 forms. The more remote the plant site is, the more extraordinary the hiding places. In addition, the adage “garbage in, garbage out” keenly applies. To avoid this concern, it is vital to check the quality of data before input.
  • Systemize and circuitize according to like service and components. Systems should be broken down into circuits of similar corrosion rates and failure mechanisms. Visual inspectors should walk down every line and piece of equipment to verify that existing drawings are accurate. It is common to find that repairs and alterations affected over the years have not been updated in plant records or drawings. Visual inspectors make changes on the drawings or draft new isometric drawings if none exist and return the drawings for CAD drafting.

Thickness monitoring locations are then assigned for ultrasonic and radiographic thickness measurements at the locations most susceptible to corrosion. TMLs are assigned to offer a representative sampling of the piping or equipment, for example, 20 percent of fittings, elevation changes, and high and low vents and drains. The inspection work is then assigned to the plant’s nondestructive testing (NDT) crew or a contractor. Data are entered into the system upon completion of the inspections.

Data and information management
An efficient plant condition management program manages data and converts it into information. Data can be numeric and text based. Numeric data include material thickness readings, corrosion coupon data, cathodic protection system data, and NDT results. Text-based data are usually reports on visual inspections performed. The use of both numeric and textual data is important in developing a cost-effective preventive maintenance program.

Although numeric thickness data provides a view of system condition, it is not complete without reports from radiography inspection and corrosion-under-insulation fluoroscopy inspection, together with other text-based data that cover external corrosion. Other failure mechanisms such as weld deterioration and wet H2S attack also are reported through textual data. The combination and compilation of these data for analysis and reporting lead to a better understanding of plant equipment and the mechanisms for potential failures.

The PCMS Users Group indicated that the keys to implementing an effective software-based plant condition management program are

  1. Develop realistic achievable objectives and agree on comprehensive guidelines
  2. Perform quality assurance checks on design data and on the historical records that will be used
  3. Estimate the work and budget realistically.

There is a popular movement in the industry toward the risk-based inspection approach to plant condition management. This approach ranks equipment according to criticality or risk, allowing inspection efforts to be focused where they can have the greatest effect in risk reduction. The correct plant condition management system provides the platform for this fundamental shift in management strategy. MT

Michael Twomey is located in the California office of Conam Inspection, Inc., Itasca, IL; (630) 773-9400; http://www.conaminsp.com. Twomey can be reached at (310) 597-3932.

Jay Rothbart is president, PCMS Enterprises, Cleveland, OH; (216) 581-5777. PCMS Enterprises, a division of Conam Inspection, Inc., provides the Plant Condition Management Systems suite of software.

Copyright 1997 Michael Twomey, Jay Rothbart, and Applied Technology Publications.

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274

8:07 pm
February 1, 1997
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CMMS Integrated with Facilities Systems

Huntsville Hospital was established in 1895 as a small infirmary serving the growing community of Huntsville, AL. The hospital has become known for its many firsts. It was the first modern hospital established in the Tennessee Valley. It opened Alabama’s first onsite employee child care center in 1967. It became northern Alabama’s first hospital to open a neonatal nursery. In 1979, doctors on the staff at the hospital performed the first cardiac catheterization in the region. Two years later, doctors completed the region’s first open heart surgery.

Consistent with all of these firsts, Huntsville Hospital also has made strides behind the scenes. For example, as part of a larger effort to install a hospital-wide facilities management system, the hospital has installed a computerized maintenance management system (CMMS) from Datastream Systems, Inc., Greenville, SC. When this system becomes fully functional, every facet of building maintenance, equipment inventory and history, asset management, purchasing, and predictive and preventive maintenance, as well as service requests from individual patients, will be automatically documented, communicated to the right people, monitored to completion, closed out, and billed. Everyone in the hospital–patients, doctors, nurses, employees, and even contractors–will have some contact with the system and will benefit from its broad perspective on automated, integrated service.

Re-engineering maintenance management
After operating for over 100 years and completing dozens of expansions, Huntsville Hospital today is a public, 901-bed, not-for-profit facility comprising Huntsville Hospital and Huntsville Hospital East. The medical staff includes more than 450 physicians representing 55 medical specialties. Joining them are 4100 employees, including a maintenance staff of 70 people.

A few years ago, Huntsville Hospital began the process of completely re-engineering the service aspects of its operations. “The goal was to remove all of the stumbling blocks that kept our service personnel from doing what they do best,” says Dave Spurlin, support services network manager. Those stumbling blocks range from receiving instructions to chasing parts to doing paperwork, and more.

At the same time, the hospital was overdue for a new CMMS. Several needs were identified. The staff wanted a system that could provide “the full spectrum of maintenance functions normally associated with operating a facility,” says Spurlin.

The hospital wanted a system that would provide an open platform for multiuser operations, information sharing, adaptability, and administrative resource sharing. “We needed a tool that did more than just maintenance; we needed a facilities management tool that included automated work order dispatch, inventory management, purchasing control, and provisions for tracking more than one person per work order,” continues Spurlin.

Because of its focus on integration with existing systems, the hospital wanted a maintenance software supplier that was experienced in providing custom work and implementation services.

Keys to facilities management
After an 18 month search concluding in June 1995, Huntsville chose Datastream’s MP2 Enterprise. A little more than a year later, the hospital has begun integrating the CMMS with three other independent systems. Together, these four systems make up the hospital’s facilities management system.

The Building Information System is a high-end computer-aided design product from Intergraph Corp. It provides detailed drawings of everything from the layout of patient rooms to the area of a new facility. It links objects shown on blueprints and other drawings to lines of information in a database, thereby giving technicians easy access to information about any subsystem in the hospital, including piping and electrical specifications, locations, vendors, model numbers, and technical diagrams.

The Building Automation System constantly monitors and controls the critical process systems within the hospital, including chillers, boilers, power systems, elevators, and heating, ventilation, and air conditioning (HVAC). It supports local and remote equipment setup, alarm management, and equipment control. The Building Automation System involves four suppliers: Automated Logic, Control Systems Inc., Landis & Gyr Power, and Trane Co.

The CMMS monitors and manages the maintenance of both nonclinical and clinical equipment throughout the hospital. “We’re talking about physical assets,” points out Spurlin. Nonclinical equipment includes systems for power distribution, emergency power, chilled and hot water, HVAC, and refrigeration–even the hospital kitchen. Clinical equipment includes ultrasound and dialysis machines, defibrillators, laboratory equipment, and other devices used by medical practitioners.

The core of the facilities management system is the Advanced Patient Response Platform (APRP), a highly sophisticated automation system developed and designed by Huntsville Hospital. It is used in several hospitals nationwide. APRP operates like a giant dispatch system, explains Spurlin. “It takes service calls from all over the hospital, regardless of what that call is and where it comes from, and routes it to the appropriate person and system.”

The four systems that make up this facilities management system run on four Hewlett-Packard dual-processor servers: two LH100-2 servers and two LC133-2 running a mix of Microsoft Windows NT 4.0 and Unix operating systems. Client systems include approximately 30 Pentium workstations and more than 70 interface stations dedicated to APRP. The Pentium workstations are multifunctional; APRP terminals communicate to the other systems through the APRP interface.

Integration is accomplished through a data network running three protocols: Novell Netware IPX/SPX, Microsoft NetGUI to perform directory services, and Microsoft TCP/IP to link databases. The databases include Informix for the Building Information System, Oracle for MP2 Enterprise, and Microsoft SQL Server for APRP. All systems share a common set of Oracle tables, which provide the primary means for the applications to communicate.

Integrated operations
The facilities management system will work to benefit patients, visitors, the maintenance department, and the hospital staff, as well as increase the overall responsiveness of the hospital.

A patient wanting a fresh pillow pushes the APRP button (similar to a call button) beside the bed. This call shows up as a request for service at the Patient Response Center. Personnel at the response center talk to the patient, determine the patient’s needs, and follow an automated process displayed by APRP to determine the most appropriate person or department to handle the request. Once the selection is made, APRP automatically transmits the request over a pager system to the appropriate person or department.

Dispatching service requests is only part of the story. All patient care employees wear a sensor device that hangs from their name badge. For example, when a nurse walks into the patient’s room to deliver the pillow, the sensor automatically identifies the nurse for APRP. If the system determines that the nurse matches the individual assigned to the open service request, APRP will terminate the service call and log the service request as complete.

If the service request is maintenance or biomedical related, the Patient Response Center instructs APRP to create a maintenance service call and transfer it to the CMMS. The system assigns a work order number to the request, creates the work order, assigns a technician, and sends the work order number back to APRP. APRP dispatches the service call over the pager system with the work order number and the location for service. The entire process usually takes 5 to 10 seconds.

A maintenance technician reading the service call on a pager can walk to the nearest terminal–located in strategic areas throughout the hospital–to access the CMMS directly for more detailed information. The portable sensor devices also monitor the movement of maintenance personnel and equipment throughout the hospital. APRP can automatically communicate the relevant maintenance-related movements of both people and equipment to the system.

Once the work order has been completed, the technician goes to the nearest touch screen terminal to close it. The technician can initiate a purchase order from the terminal if the work order cannot be completed because spare parts are not in stock. “The CMMS documents the service requests from a maintenance history standpoint,” explains Spurlin. “With that, we now have a means to track the number and type of work order requests, as well as a better method for scheduling preventive maintenance on pieces of equipment and areas of the hospital needing emergency or routine repair.”

Saving money, satisfying regulatory agencies
“When integration of the CMMS with the other systems is complete, we will have created a totally paperless system for our maintenance operation,” continues Spurlin. “With 14,800 inventory items and nearly 38,000 issued work orders to date—over 100 per day—the CMMS and APRP link is invaluable to our hospital’s success.”

To date, the system has successfully put a lock on inventory. Because of its growth and continual expansion, Huntsville Hospital routinely hires outside contractors for construction projects. Often, these contractors pulled equipment and tools from the hospital’s inventory without documenting their use, causing an enormous problem for the hospital maintenance staff who were unable to account for inventory. Now, contractors can access the CMMS along with the hospital’s employees. And like those employees, the contractors have a tool to track all inventory items.

The CMMS also controls contract work. Work orders displayed are essentially the contractor’s purchase order to proceed with the job. If the job is not on a work order, the contractor does not get paid for it. “Now we have a way to keep track of billings and contracted maintenance work. Plus, our inventory shrinkage has been drastically reduced, immediately saving the hospital $7200,” says Spurlin.

Other information on line lets the maintenance department forecast future work load and schedule work appropriately. “I can avoid having 300 hours of labor available for a 600 hour load. Before, I wouldn’t know about this until the paperwork came off the printer,” says Spurlin. Work schedules can be adjusted 90 days–even 6 months–in advance. Maintenance not only stays on schedule, but the hospital is freed from paying extra in overtime or contract labor.

The CMMS also has done its duty as an analytical tool. “It shows us exactly how much time we spend chasing parts,” explains Spurlin. “And it has shown where we can easily save $50,000 by improving the way we perform maintenance.”

Huntsville Hospital also purchased several optional modules for the CMMS. The Occupational Safety & Health Administration (OSHA) database, for example, can print references for major certification inspection requirements directly from the CMMS, information that would have taken weeks to acquire without the data-base.

OSHA is not the only regulatory agency concerned with maintenance documentation. The Joint Commission on Accreditation of Healthcare Organizations (JCAHO), which accredits hospitals, views equipment maintenance as essential to the safety and well-being of the patient. JCAHO’s view is that if the paperwork and documentation are not done, the job is not done, regardless of how many people are saved. And the legal system agrees; maintenance documentation is absolutely crucial from a liability standpoint.

Huntsville Hospital is realizing its main goal of creating a seamlessly integrated facility management system. “That brings us back to the issue of openness,” says Spurlin, “aided not only by the design of MP2 Enterprise, but also the openness of the company’s staff to work with us in making this system work.”

For example, at the request of the hospital, custom menus and screens were created, making them easier for the entire hospital staff to use. Similarly, touch screens were installed as a user-friendly feature of the terminals. “The seamless integration of the CMMS into our existing facilities package will make the hospital even more responsive to maintenance-related needs and issues,” concludes Spurlin. MT

Information supplied by Datastream Systems, Inc., Greenville SC; telephone (800) 955-6775.

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