Remerciez-le!

Remerciez @Admin pour avoir partagé cet document gratuitement, de la manière la plus simple, en partageant sur les réseaux sociaux.

US Army Corps of Engineers Construction Engineering Research Laboratories Relia

US Army Corps of Engineers Construction Engineering Research Laboratories Reliability Centered Maintenance (RCM) Guide Operating a More Effective Maintenance Program Alan Chalifoux and Joyce Baird This manual outlines a comprehensive method of organizing an efficient maintenance program by applying the concepts of Reliability Centered Maintenance (RCM). RCM combines professional intuition and a rigorous statistical approach, and recognizes that different maintenance strategies apply to different facility equipment: run-to-failure, preventive, predictive, and proactive maintenance. The RCM approach applies these differing maintenance strategies in an optimal mix, to ensure that facility equipment is maintained sufficient to accomplish the facility mission without wasting maintenance labor. This guide is meant to help maintenance supervisors, managers, and technicians organize and operate an efficient and effective maintenance program in an environment of maintenance budget cutbacks. Approved for public release; distribution is unlimited. USACERL Technical Report 99/41 April 1999 USACERL TR 99/41 1 Executive Summary Maintenance management is a complicated business. Facility maintenance budgets are continually scrutinized by fiscal managers in a constant effort to trim dollars. Maintenance managers are under constant pressure to squeeze every last bit of productivity out of every maintenance dollar. This manual outlines a comprehensive method of organizing an efficient mainte- nance program through applying the concepts of Reliability Centered Mainte- nance (RCM). Combining professional intuition and a rigorous statistical ap- proach, RCM recognizes that there are different maintenance strategies followed for different facility equipment: run-to-failure, preventive maintenance, predic- tive maintenance, and proactive maintenance. The RCM approach applies these differing maintenance strategies in an optimal mix, to ensure that facility equipment is being maintained sufficient to accomplish the facility mission with- out wasting inordinate amounts of maintenance labor “baby sitting” facility equipment. This manual presents the RCM approach for maintenance supervisors, manag- ers, and technicians to use as a guide in organizing and operating a tight, cost- effective, “lean and mean” maintenance program in light of and in spite of the continual cutbacks in maintenance budgets. 2 USACERL TR 99/41 Foreword This study was conducted for the Facilities Management Division (EMD) at Madigan Army Medical Center (MAMC) under Project 4A162720D048, “Indus- trial Operations Pollution Control Technology.”; Work Unit Y67, “Reliability Cen- tered Maintenance.” The technical monitor was Michael Carico, MAMC-FMD. The work was performed by the Industrial Operations Division (UL-I) of the Utilities and Industrial Operations Laboratory (UL), U.S. Army Construction Engineering Research Laboratories (CERL). The CERL principal investigators were Alan Chalifaux and Jearldine I. Northrup. Special credit is given to the National Aeronautics and Space Administration (NASA) for the use of its docu- ment Reliability Centered Maintenance Guide for Facilities and Collateral Equipment, December 1996 in the preparation of this report. Walter J. Mikucki is Chief, CECER-UL-I; Dr. John Bandy is Laboratory Operations Chief, CECER- UL; and Gary W. Schanche was the responsible Technical Director, CECER-TD. The CERL technical editor was William J. Wolfe, Technical Information Team. Dr. Michael J. O’Connor is Director of USACERL. USACERL TR 99/41 3 Contents Executive Summary .........................................................................................................1 Foreword............................................................................................................................2 1 Introduction.................................................................................................................9 Background .........................................................................................................................9 Objectives..........................................................................................................................12 Approach...........................................................................................................................13 Scope ................................................................................................................................13 Units of Weight and Measure............................................................................................13 2 RCM Definition and Philosophy .............................................................................14 Definition ...........................................................................................................................14 RCM Analysis....................................................................................................................14 RCM Principles .................................................................................................................15 The RCM Process.............................................................................................................17 RCM Program Benefits .....................................................................................................19 Impact of RCM on a Facility’s Life Cycle...........................................................................22 3 RCM Program Components....................................................................................24 Reactive Maintenance.......................................................................................................24 Preventive Maintenance (PM)...........................................................................................25 Preventive Maintenance Criteria ..................................................................................................26 Determining PM Task and Monitoring Periodicity.........................................................................26 Condition Monitoring (CM)................................................................................................28 Proactive Maintenance......................................................................................................30 Specifications for New/Rebuilt Equipment ........................................................................31 Balance........................................................................................................................................32 Alignment.....................................................................................................................................34 Alignment Effects .........................................................................................................................35 Failed-Part Analysis .....................................................................................................................37 Root-Cause Failure Analysis (RCFA)...........................................................................................37 Reliability Engineering and Reliability Calculations......................................................................38 Rebuild Certification/Verification ..................................................................................................42 Age Exploration............................................................................................................................42 Recurrence Control......................................................................................................................43 4 USACERL TR 99/41 Facility Condition Assessment .....................................................................................................44 4 Use of Condition Monitoring (CM) Technologies .................................................45 Introduction .......................................................................................................................45 Spot Readings versus Continual Real-Time Data Collection ...........................................45 5 Vibration Monitoring and Analysis.........................................................................47 Theory, Applications, and Techniques...............................................................................47 Basic Vibration Theory .................................................................................................................47 Information Obtained through Vibration Monitoring......................................................................51 Detection Interval/Amount of Data Collected ...............................................................................52 Overall Vibration...........................................................................................................................52 Spectrum Analysis and Waveform Analysis .................................................................................52 Torsional Vibration........................................................................................................................53 Multi-Channel Vibration Analysis..................................................................................................53 Shock Pulse Analysis...................................................................................................................53 Vibration Sensor Mounting (Permanent Installations) ..................................................................53 Laser Shaft Alignment..................................................................................................................54 Limitations .........................................................................................................................54 Logistics ............................................................................................................................54 Equipment Required ....................................................................................................................54 Operators.....................................................................................................................................55 Available Training .........................................................................................................................55 Cost .............................................................................................................................................55 6 Thermography ..........................................................................................................56 Theory and Applications ...................................................................................................57 Limitations .........................................................................................................................58 Logistics ............................................................................................................................58 Equipment Required ....................................................................................................................58 Operators.....................................................................................................................................58 Training Available .........................................................................................................................58 Cost .............................................................................................................................................59 7 Passive (Airborne) Ultrasonics...............................................................................60 Theory, Applications, and Techniques...............................................................................60 Basic Theory of Ultrasonic Detection ...........................................................................................61 Leak Detection.............................................................................................................................62 Electrical Problems ......................................................................................................................65 Mechanical Inspection .................................................................................................................66 Ultrasonic Translators...................................................................................................................69 Limitations .........................................................................................................................69 USACERL TR 99/41 5 Logistics ............................................................................................................................69 Equipment Required ....................................................................................................................70 Operators.....................................................................................................................................70 Training Available/Required..........................................................................................................70 Cost .............................................................................................................................................70 8 Lubricant and Wear Particle Analysis....................................................................71 Purpose.............................................................................................................................71 Machine Mechanical Wear Condition...........................................................................................71 Lubricant Condition......................................................................................................................71 Lubricant Contamination..............................................................................................................72 Standard Analytical Tests..................................................................................................72 Visual and Odor ...........................................................................................................................72 Viscosity.......................................................................................................................................73 Water ...........................................................................................................................................73 Percent Solids/Water....................................................................................................................73 Total Acid Number (TAN)..............................................................................................................73 Total Base Number (TBN)............................................................................................................74 Spectrometric Metals ...................................................................................................................74 Infrared Spectroscopy..................................................................................................................74 Analytical Ferrography .................................................................................................................74 Special Tests .....................................................................................................................75 Glycol Antifreeze..........................................................................................................................75 Karl Fischer Water .......................................................................................................................75 Application.........................................................................................................................76 Motors, Generators, Pumps, Blowers, Fan...................................................................................77 Gearboxes ...................................................................................................................................77 Chillers.........................................................................................................................................78 Diesel Engines.............................................................................................................................78 Compressors ...............................................................................................................................78 Hydraulic Systems .......................................................................................................................78 Large Reservoirs..........................................................................................................................78 Lubrication Analysis.....................................................................................................................78 Sampling......................................................................................................................................79 9 Electrical Condition Monitoring..............................................................................80 Techniques ........................................................................................................................80 Megohmmeter Testing..................................................................................................................81 High Potential Testing (HiPot).......................................................................................................81 Surge Testing ...............................................................................................................................81 Conductor Complex Impedance...................................................................................................82 Time Domain Reflectometry ........................................................................................................82 6 USACERL TR 99/41 Motor Current Spectrum Analysis (MCSA) ..................................................................................82 Radio Frequency (RF) Monitoring................................................................................................82 Power Factor and Harmonic Distortion ........................................................................................82 Motor Current Readings...............................................................................................................83 Airborne (Passive) Ultrasonics.....................................................................................................83 Transformer Oil Analysis ..............................................................................................................83 Applications.......................................................................................................................83 Equipment to be Monitored..........................................................................................................83 Conditions Monitored...................................................................................................................84 Detection Interval.........................................................................................................................84 Accuracy ......................................................................................................................................84 Limitations....................................................................................................................................84 Logistics ............................................................................................................................85 Equipment Required ....................................................................................................................85 Operations ...................................................................................................................................85 Training Available .........................................................................................................................85 Cost .............................................................................................................................................85 10 Non-Destructive Testing ..........................................................................................86 Techniques ........................................................................................................................86 Radiography.................................................................................................................................86 Ultrasonic Testing (Imaging).........................................................................................................87 Magnetic Particle Testing .............................................................................................................88 Dye Penetrant ..............................................................................................................................89 Hydrostatic Testing.......................................................................................................................89 Eddy Current Testing....................................................................................................................89 Location and Intervals.......................................................................................................90 Intervals .......................................................................................................................................90 Locations .....................................................................................................................................92 Applications.......................................................................................................................92 Limitations .........................................................................................................................93 11 Conclusions..............................................................................................................95 References.......................................................................................................................96 Distribution USACERL TR 99/41 7 List of Figures and Tables Figures 1 Bearing life scatter. ....................................................................................................11 2 RCM logic tree...........................................................................................................17 3 Sample RCM system data sheet...............................................................................19 4 Sample failure mode sheet........................................................................................20 5 Failure mode sheet for bearings................................................................................21 6 Failure mode sheet for stator. ....................................................................................21 7 Maintenance cost trends under an RCM program. ...................................................22 8 Stages of life cycle cost commitment. .......................................................................23 9 Decrease in life of cylindrical roller bearings as a function of misalignment. ............36 10 Sample vibration data................................................................................................50 11 Two plots of vibration data juxtaposed in the same graph.........................................51 Tables 1 Recommended coupled alignment tolerances (General Motors, 1993)....................35 2 Recommended maximum inspection intervals (API 570). ........................................90 USACERL TR 99/41 9 1 Introduction Background Maintenance often takes a low priority in the overall operating strategy of a fa- cility. Maintenance programs are managed and funded by people, and human nature seems to abide the old tenet, “If it ain’t broke, don’t fix it.” In facilities management the definition of “broke” is extreme. “Broke” typically means that a piece of equipment has catastrophically failed (e.g., resulting in a pollution fine), or (at the very least) that it has failed to the point that it has become an annoy- ing disturbance in the normal daily operation of a facility. While few people will argue against the need for performing regular mainte- nance, few fiscal managers will make the financial commitment to funding main- tenance programs at a level that will keep a facility well maintained. Fiscal managers usually assign maintenance programs a very low priority. Compared to other facility departments, maintenance departments have no real “product” and - as such - produce no real income. Many fiscal managers view money spent on maintenance as money thrown down a black hole. In spite of any life-cycle “proofs” to the contrary, fiscal managers look to cut maintenance budgets first when any other fiscal need arises. Not until they see the bathroom floor flooded with sewage or swelter in an office working at 85 °F for hours do they realize that something is “broken” and may need repair. Fiscal managers continually put maintenance budgets under the closest scrutiny in an effort to reduce dollars spent on maintenance, while expecting facility per- formance to remain on a constant par. This forces maintenance supervi- sor/managers to trim essential (but less obvious) work from their daily agendas. The most common area trimmed is preventive maintenance, i.e., those mainte- nance activities performed on facility equipment before equipment failure. The importance of preventive maintenance is less obvious to those people not inti- mately familiar with facility equipment and operation. The consequences and cost of not performing PM only become obvious when it is too late. Preventive maintenance requires that maintenance personnel pay regular visits to observe the condition of facility equipment. The most basic tasks on these PM visits is to take a look at the equipment to see if there are any telltale signs of 10 USACERL TR 99/41 failure or imminent failure. Also, depending on the type of equipment, the main- tenance mechanic may have a checklist of tasks he has to perform (e.g., draining a little oil and visually checking for foreign matter or discoloration). In large fa- cilities such as MAMC, the basic PM task of walking out to a piece of equipment and giving it a quick look over requires a great deal of time. It also requires that this time be invested by a trained mechanic; untrained personnel are likely to miss telltale signs of failure. uploads/Management/ rcm-guide.pdf