1、Designation: D7874 13Standard Guide forApplying Failure Mode and Effect Analysis (FMEA) to In-Service Lubricant Testing1This standard is issued under the fixed designation D7874; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide describes a methodology to select tests to beused for in-service lubricant analysis. The selection
3、of fluidtests for monitoring failure mode progression in industrialapplications applies the principles of failure mode and effectanalysis (FMEA).1.2 Although typical FMEA addresses all possible productfailure modes, the focus of this guide is not intended to addressfailures that have a very high pro
4、bability of unsafe operation asthese should immediately be addressed by other means.1.3 This guide is limited to components selected forcondition-monitoring programs by providing a methodology tochoose fluid tests associated with specific failure modes for thepurpose of identifying their earliest de
5、veloping stage andmonitoring fault progression. The scope of this guide is alsofocused on those failure modes and their consequences that caneffectively be detected and monitored by fluid analysis tech-niques.1.4 This guide pertains to a process to be used to ensure anappropriate amount of condition
6、 monitoring is performed withthe objective of improving equipment reliability, reducingmaintenance costs, and enhancing fluid analysis monitoring ofindustrial machinery. This guide can also be used to select themonitoring frequencies needed to make the failure determina-tions and provide an assessme
7、nt of the strengths and weak-nesses of a current condition-monitoring program.1.5 This guide does not eliminate the programmatic require-ments for appropriate assembly, operational, and maintenancepractices.1.6 This standard does not purport to address all of thesafety concerns, if any, associated w
8、ith its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D7684 Guide for Microscopic Characterization of Particlesfrom In-
9、Service LubricantsD7720 Guide for Statistically Evaluating Measurand AlarmLimits when Using Oil Analysis to Monitor Equipmentand Oil for Fitness and Contamination2.2 IEC Standard:IEC 60812 Analysis Techniques for System ReliabilityProcedure for Failure Mode and EffectsAnalysis (FMEA),20063. Terminol
10、ogy3.1 Definitions:3.1.1 cause(s) of failure, nunderlying source(s) for eachpotential failure mode that can be identified and described byanalytical testing.3.1.2 component incipient failure, nmoment a componentbegins to deteriorate or undergo changes that will eventuallylead to the loss of its desi
11、gn function.3.1.2.1 DiscussionThis moment may not be easily detect-able because of sensitivity limitations of monitoring instrumen-tation or a lack of measurable change in performance charac-teristics or both.3.1.3 criticality number, C, nproduct of the severity (S)and occurrence (O) numbers for a g
12、iven failure modes causesand effects.3.1.4 design function, nfunction or task that the system orcomponent should perform.3.1.5 detection ability number, D, nranking number thatdescribes the ability of a specific fluid test to successfullydetect a failure modes causes or effects. A scale is used togr
13、ade detection ability numbers; see an example in 6.4.7.3.1.6 effect(s) of failure, npotential outcome(s) of eachfailure mode on the system or component.1This guide is under the jurisdiction of ASTM Committee D02 on PetroleumProducts, Liquid Fuels, and Lubricants and is the direct responsibility of S
14、ubcom-mittee D02.96.04 on Guidelines for In-Services Lubricants Analysis.Current edition approved Oct. 1, 2013. Published October 2013. DOI: 10.1520/D7874-13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of A
15、STMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.7 failure-developing period, FDP, nperiod from com-ponents incipient failure to funct
16、ional failure.3.1.8 failure mode, nphysical description of the manner inwhich a failure occurs.3.1.9 failure mode and effect analysis, FMEA, nanalyticalapproach to determine and address methodically all possiblesystem or component failure modes and their associated causesand effects on system perfor
17、mance.3.1.9.1 DiscussionThis approach can be used to evaluatedesigns and track risk-reducing improvements to equipmentreliability.3.1.10 failure modes, effects, and criticality analysis,FMECA, nextension to FMEA that involves ranking the riskassociated with failure modes to allow prioritization ands
18、election of an appropriate maintenance strategy.3.1.10.1 DiscussionA metric-describing criticality is de-termined by the product of a severity number (S) and itsoccurrence number (O) for each given failure modes causesand effects.3.1.11 functional failure, ninability of the component orsystem to per
19、form its required design function.3.1.12 occurrence number, O, nranking number that de-scribes the probability of occurrence of a failure modes causesand effects over a predetermined period of time based on pastoperating experience in similar applications; see an example in6.3.2.3.1.13 P-F curve, ni
20、llustration of component failure pro-gression (component condition versus time) from incipientfailure to functional failure (F).3.1.14 P-F interval, nperiod from the point in time inwhich a change in performance characteristics or condition canfirst be detected (P) to the point in time in which func
21、tionalfailure (F) will occur as illustrated on a P-F curve.3.1.15 severity number, S, nranking number that describesthe seriousness of the consequences of each failure modescauses and effects on potential injury, component or equipmentdamage, and system availability.3.1.15.1 DiscussionA scale is use
22、d to grade severitynumbers. See an example in 6.3.1.4. Summary of Guide4.1 This guide is designed to aid the user to optimize theircondition-monitoring program.4.2 Failure mode and effect analysis (FMEA) is applied bythe user of this guide to those machines selected in theircondition-monitoring prog
23、ram based on their significance toproduction and safety. The user of this guide determines thepossible failure modes for each machine and applies FMEAseparately for each failure mode. A severity number (S) isassigned for each failure modes causes and effects.4.3 The user of this guide then determine
24、s how frequentlythe failure modes causes or effects are likely to occur based onpast operating experience under similar applications for apredetermined time period. An occurrence number (O)isassigned for each failure modes causes and effects.4.4 The severity and occurrence numbers are constant forea
25、ch failure modes specific cause or effect. Calculating theproduct of the severity and occurrence numbers (criticalitynumber) for all failure modes causes and effects allows theuser to establish a ranked hierarchy of the risk associated withequipment failure. A table matrix of severity versus occurre
26、nceranks can then be used to allow the user to determine whethera given failure modes cause or effect is tolerable and requiresperiodic inspection, fluid testing, or design modification (forexample, Table 1). This is used to justify the need for testing ofspecific failure modes causes or effects wit
27、hin a predictivemaintenance program.4.5 For those failure modes causes and effects that requirefluid testing, several test methods should be considered. Adetection ability number (D) is determined by the user for eachtest method based on the tests ability to detect the failuremodes causes and effect
28、s. By comparing the ranking ofcriticality numbers with their corresponding detection abilitynumbers, the user may assess the strengths and weaknesses oftheir fluid testing program. Cases in which the detection abilitynumbers are low compared to a high corresponding criticalitynumber indicates weakne
29、ss within a fluid testing program.TABLE 1 Criticality MatrixOccurrenceNumberSeverity NumberS-1InsignificantS-2MarginalS-3ModerateS-4CriticalS-5CatastrophicO-1ImprobableTolerable Tolerable PeriodicInspectionPeriodicInspectionTestingO-2RemoteTolerable PeriodicInspectionPeriodicInspectionTesting Testin
30、gO-3OccasionalPeriodicInspectionPeriodicInspectionTesting Testing TestingO-4ProbablePeriodicInspectionTesting Testing Testing DesignModificationO-5FrequentTesting Testing Testing DesignModificationDesignModificationD7874 1324.6 An optimal sampling interval with consideration to thecost of sampling a
31、nd benefits to the monitoring program canalso be determined to implement a balanced testing approach.5. Significance and Use5.1 This guide is intended as a guideline for fluid analysisprograms and serves as an initial justification for selecting fluidtests and sampling frequencies. Plant operating e
32、xperiencealong with the review and benchmarking of similar applica-tions is required to ensure that lessons learned are imple-mented.5.2 Selection of proper fluid tests for assessing in-servicecomponent condition may have both safety and economicimplications. Some failure modes may cause componentdi
33、sintegration, increasing the safety hazard. Thus, any fluid testthat can predict such conditions should be included in thecondition-monitoring program. Conversely, to maintain a sus-tainable and successful fluid-monitoring program, the scope ofthe fluid tests and their frequency should be carefully
34、balancedbetween the associated risks versus expected program costsavings and benefits.5.3 The failure modes monitored may be similar from oneapplication to the next, but the risk and consequences of failuremay differ.5.4 This analysis can be used to determine which in-servicelubricant analysis tests
35、 would be of highest value and whichwould be ineffective for the failure modes of interest. Thisinformation can also be used to determine the best monitoringstrategy for a suite of failure modes and how often assessmentis needed to manage the risk of failure.6. Failure Mode and Effect Analysis (FMEA
36、)6.1 The FMEA process requires a thorough understandingof machine design requirements and equipment operatingconditions. Detailed knowledge is required of the componentdesign configuration, dimensional tolerances, load directions,design limitations, lubrication mechanisms, lubricantcharacteristics,
37、metallurgy of lubricated components, and en-vironmental conditions. System significance, equipmentaccessibility, and application of on-line sensors or other moni-toring techniques (for example, vibration, ultrasound, andthermal images) also provide critical information in thisanalysis process.Acommi
38、ttee of individuals may be assembledto ensure the listed knowledge areas are properly represented.6.2 An overview of the FMEA process is presented in Fig.1.6.3 The FMEA methodology prioritizes failures modesbased on how serious the consequences of their effects are (S)and how frequently they are exp
39、ect to occur (O).6.3.1 For in-service fluid analysis applications, S is catego-rized according to a ranked-number scale. An example isprovided here of a five-rank scale; however, users may modifythis scale to satisfy their specific requirements.6.3.1.1 Number S-1 indicates an insignificant condition
40、 thathas little to no effect on component performance.6.3.1.2 Number S-2 indicates a marginal condition thatcauses a minor effect on component performance without theneed for repair.6.3.1.3 Number S-3 indicates a moderate condition thatreduces component performance and requires repair.6.3.1.4 Number
41、 S-4 indicates a critical condition caused bythe loss of component design function that makes the compo-nent inoperable.6.3.1.5 Number S-5 indicates a catastrophic conditioncaused by the loss of component design function that mayendanger the operator and others.6.3.2 For in-service fluid analysis ap
42、plications, O is catego-rized according to a ranked-number scale. An example isprovided here of a five-rank scale. As previously mentioned,users may modify this scale to satisfy their specific require-ments.6.3.2.1 Number O-1 indicates improbable occurrence basedon no identified failures in similar
43、applications.6.3.2.2 Number O-2 indicates remote occurrence based on avery few number of failures in similar applications for apredetermined operational period.6.3.2.3 Number O-3 indicates occasional occurrence basedon a moderate number of failures in similar applications for apredetermined operatio
44、nal period.6.3.2.4 Number O-4 indicates probable occurrence based ona high number of failures in similar applications for a prede-termined operational period.6.3.2.5 Number O-5 indicates frequent occurrence based ona very high number of failures in similar applications for apredetermined operational
45、 period.6.3.3 The predetermined operational period is selected bythe user based on factors such as production schedules, outageand inspection intervals, and so forth.6.4 Failure mode, effects, and criticality analysis (FMECA)is a part of FMEA.6.4.1 Criticality numbers are calculated for all failurem
46、odes causes and effects by multiplying their severity (S),6.3.1, and occurrence numbers (O), 6.3.2.6.4.2 Criticality numbers are then used to quantify therelative magnitude of each failure modes causes and effects toestablish a ranked hierarchy of equipment failure risk andadjust the condition-monit
47、oring program in response.6.4.3 To improve analysis efficiency, the list of failure modecauses and effects should be rearranged according to thehierarchy of criticality numbers.6.4.4 The hierarchy of criticality numbers can be listedusing either their actual criticality values or their numericalrank
48、ing in the hierarchy (for example, 1, 2, 3, and so forth).The list of actual criticality values may provide additionalinformation about the difference in magnitude of risk betweeneach rank.6.4.5 The user should develop a criticality table matrix ofseverity versus occurrence ranks that can be used to
49、 determinethe preferable maintenance approach for the detection of eachparticular failure modes cause or effect. An example of such acriticality matrix is provided in Table 1.6.4.6 For failure mode causes and effects that require fluidtesting, users should consider a broad selection of differentD7874 133fluid test methods capable of detecting and monitoring theprogression of the specific failure modes.6.4.7 For each fluid test method, users should assign adetection ability number, D, based on how easily and reliablythe failure modes causes and
