发动机故障询问与分析

故障分析检查

FailureAnalysisReview发动机为何发生故障?该故障是否在保修范围内?Whydidthisenginefailandisitawarrantablefailure?故障分析过程

TheProcessofFailureAnalysis询问顾客Questionthecustomer

核实投诉/症状

Verifycomplaints/symptoms

拆卸Disassemble

定义故障类型Definethetypeoffailure

确定原因Determinethecause

排除故障原因，防止再次发生。Correctthecauseoffailuretopreventfurtheroccurrence.询问顾客

QuestiontheCustomer询问维护记录

Askaboutmaintenancehistory

问题发生持续时间Lengthofproblemoccurrence

故障发生前的症状(如噪音、烟雾等)Symptomspriortofailure(i.e.,noise,smoke,etc..)

故障发生前是否有任何异常Anyabnormalitiespriortofailure

操作机器的人是否为机器所有者Wasowneroperatingmachine核实投诉和检查症状

VerifyComplaint&CheckSymptoms运行状态是否与描述的一样?Isitworkingasdescribed?检查以下各项LOOKFORTHEFOLLOWING

漏油OilLeaks

烟雾Smoke

检查液位Checkfluidlevels

机器的整体状况Overallconditionofunit

是否有任何改造Anymodifications拆卸

Disassembly拆卸零件/发动机Disassemblethecomponent/engine放置好零件，使其免受损坏并便于以后检查Organizepartstoprotectfromdamageandforlaterreview如有需要，对油、燃料和冷却液进行采样Takeoil,fuel,andcoolantsamplesincasetheyareneeded寻找解决疑难问题的线索Lookforcluestosolvethemystery故障类型

TypesofFailure活塞环损坏和故障PistonRingDamage&Failure活塞损坏和故障PistonDamage&Failure轴承故障BearingFailures曲轴故障CrankshaftFailures其它零件故障Othercomponents活塞环故障分析

PistonRingFailureAnalysis微粒磨损FineAbrasiveWear环划痕RingScoring粘性环StickingRings断裂Breakage微粒磨损

FineAbrasiveWear外观/线索：Appearance/Clues:外表呈暗灰色DullGrayFinish细小垂直划痕FineVerticalScratches积碳CarbonBuild-up环形槽磨损WornRingGrooves油环轨磨损WornOilRingRails微粒磨损

FineAbrasiveWear可能的原因：PossibleCauses:空气滤清器泄漏LeaksinAirCleaner空气过滤器维护不当ImproperAirFilterMaintenance维修后发动机中留有磨屑AbrasivesLeftinEngineafterRepair加油时漏斗中有脏物DirtinFunnelswhenAddingOil环划痕

RingScoring外观/线索Appearance/Clues金属错位造成的明显凹槽VisibleGroovesCausedbyDisplacedMetal可能是钢制零件变色PossibleDiscolorationofSteelParts刮伤的环

ScoredRings可能的原因：PossibleCauses:缺少润滑LackofLubrication过度供油Overfueling冷却液泄漏到气缸内CoolantLeakingintoCylinder过热和过载Overheating&Overloading活塞上有积碳CarbonBuilduponpiston粘性环

StickingRings外观/线索Appearance/Clues环上沉积物过多ExcessiveRingDeposits环过度磨损ExcessiveRingWear环被卡在槽内RingsSeizedinGrooves环和活塞在后阶段磨擦ScuffingofRingsandPistonsinLaterStages粘性环

StickingRings可能的原因：PossibleCauses:沉积物过多ExcessiveDeposits燃烧不充分PoorCombustion过早磨损PrematureWear发动机油使用时间过久ExtendedEngineOilService环断裂

RingBreakage外观/线索Appearance/Clues断裂！Broken!磨损或刮伤ScuffingorScoring槽变宽或变形WidenedorDeformedGroove气缸壁有划痕CylinderWallScratching新断裂处FreshBreak!断裂的环

BrokenRings可能的原因：PossibleCauses:组装不当ImproperAssembly冲击载荷ShockLoading环槽过宽ExcessiveRingGrooveWidth积碳过多ExcessiveCarbonBuild-up使用了启动剂UseofaStartingAgent除尘不当SevereDusting是的，如果对发动机除尘，拆下了活塞而没有拆下环脊，可能会弄断环，这可能就是导致故障的原因。Yes,ifanengineisdustedandyouremovethepistonswithoutremovingtheridge,youmaybreaktheringsandthinkthattheyarethecauseoffailure.活塞故障分析

PistonFailureAnalysis微粒磨损FineAbrasiveWear爆裂Detonation活塞磨损PistonScuffing活塞刮伤PistonScoring活塞卡住PistonSeizure过热Overheating腐蚀Erosion断裂Breakage微粒磨损

FineAbrasiveWear外观/线索Appearance/Clues外表呈暗灰色DullGrayFinish细小垂直划痕FineVerticalScratches环槽磨损WornRingGrooves油环轨磨损WornOilRingRails积碳CarbonBuild-up微粒磨损

FineAbrasiveWear可能的原因：PossibleCauses:空气滤清器维修过度Over-servicingAirCleaner空气过滤器系统泄漏LeaksinAirFilterSystem来自脏漏斗中的脏物DirtfromDirtyFunnels大修后发动机中留有磨屑AbrasivesLeftinEngineafterOverhaul爆裂

Detonation外观/线索Appearance/Clues活塞断裂FracturedPiston穿孔Holes零件断裂PartsBroken爆裂

Detonation可能的原因：PossibleCauses:启动剂StartingAgents正时不正确IncorrectTiming发动机振动Lugging冷却不足InadequateCooling燃料中有汽油GasolineinFuel活塞磨损

PistonScuffing外观/线索Appearance/Clues垂直划痕VerticalScratches外表呈暗灰色DullGrayFinish环槽磨损WornRingGrooves活塞磨损

PistonScuffing可能的原因：PossibleCauses:间歇性润滑不足IntermittentLackofLubrication预热时间过短ImproperWarm-up过度供油Overfueling过热/100%防冻剂Overheating/100%Antifreeze过载Overloading重新装配时，磨屑清洗不当ImproperCleaningofAbrasivesduringRebuild活塞刮伤

PistonScoring外观/线索Appearance/Clues金属错位造成的明显凹槽VisibleGroovesCausedby

DisplacedMetal可能是钢制零件变色PossibleDiscolorationofSteelParts活塞刮伤

PistonScoring可能的原因：PossibleCauses:过热Overheating缺少润滑LackofLubrication过度供油Overfueling环棱中或活塞上有积碳CarbonBuild-upinRingLandoronPiston活塞卡住

PistonSeizure外观/线索Appearance/Clues严重刮伤和金属变形SevereScoring&MetalTransfer可能是销径处的活塞断裂PossiblePistonBreakageatPinBore活塞或环棱熔化，热变色MeltedPistonorRingLands,HeatDiscoloration裂缝Cracking活塞卡住

PistonSeizure可能的原因：PossibleCauses:大修中使用了错误的活塞WrongPistonusedDuringOverhaul缺少润滑LackofLubrication活塞销/径断裂PistonPin/BoreBreakage气缸中有冷却液CoolantinCylinder以下是活塞卡住的示例，活塞上留下的痕迹是阀撞击造成的损伤。ExampleofPistonSeizurewithdamagefromvalvehittingwhatwasleftofpiston腐蚀

Erosion外观/线索Appearance/Clues表面磨损或腐蚀WornawayorErodedSurface表面生锈、有蚀坑Rusted,PittedSurface表面有气蚀的凹坑CavitationPittedSurface腐蚀

Erosion可能的原因：PossibleCauses:燃料喷油嘴泄漏LeakingFuelInjector正时提前AdvancedTiming在高处运转而功率不降低HighAltitudeOperationwithoutDerating活塞环断裂BrokenPistonRings断裂

Breakage外观/线索Appearance/Clues活塞破碎PistoninPieces刮伤Scoring阀标记ValveMarkings热变色HeatDiscoloration断裂

Breakage可能的原因：PossibleCauses:卡住Seizure使用了乙醚EtherUsage预燃室松动LoosePre-CombustionChambers过度供油Overfueling进气口中有碎片DebrisinAirIntake轴承故障分析

BearingFailureAnalysis轴承变色BearingDiscoloration轴承缺油OilStarvation过载Overloading放电故障ElectricDischargeFailure磨蚀Fretting气蚀CavitationErosion轴承变色

BearingDiscoloration外观/线索Appearance/Clues轴承边缘呈现乳灰色MilkyGrayonEdgeofBearing轴承边缘有黑色腐蚀BlackCorrosiononEdgeofBearing非常暗的灰色，比较光滑的表面VeryDullGray,RelativelySmoothSurface青蓝色/黑色Bluish/Black有黑色的“痕迹”，像拖痕和穿过轴承电弧焊机的电极Black“Tracks”,LikeDraggingandArcWelderElectrodeAcrossBearing轴承中的油槽黑化OilGroovesinBearingareBlackened轴承变色

BearingDiscoloration可能的原因：PossibleCauses:水/防冻剂污染Water/AntifreezeContamination润滑不足InsufficientLubrication微粒磨光FineParticlePolishing油温高HighOilTemperature燃料污染FuelContamination放电ElectricDischarge轴承缺油

OilStarvation外观/线索Appearance/Clues磨损的表面发亮ShinyWearSurface污点Smearing,then磨损Scuffing,then刮伤Scoring,then卡住Seizure,then孔径内旋转SpinninginBore在“高负载”区域显示过早磨损ShowsPrematureWearin“HighLoad”Areas轴承缺油

OilStarvation可能的原因：PossibleCauses:油被稀释DilutionofOil油位低LowOilLevel滤油器或滤网堵塞RestrictedOilFilterorScreen油泵磨损WornOilPump油盘堵塞RestrictedOilGalleys吸附碳或污垢CarbonorDirtIngestion润滑不足

InsufficientLubrication这是润滑不足的个案研究示例。ThisisaCaseStudyexampleofinsufficientlubrication.连杆主线过载

Overloading外观/线索Appearance/Clues“高负载”区域的磨损Wearon“HighLoad”Areas轴承被锤打变薄BearingHammeredThin发出锤打噪音(敲击)HammeringNoises(Knock)过载

Overloading可能的原因：PossibleCauses:发动机振动LuggingtheEngine在齿轮速度过高的状态下运行机器OperatingUnitinTooHighofGear试图运行更大的机器AttemptingtodoWorkofaLargerUnit放电故障

ElectricDischargeFailure外观/线索Appearance/Clues曲轴的表面结霜FrostedAppearanceofCrankshaft主轴承“高负载”区域中的过早磨损PrematureWearinMainBearing“HighLoad”Area连杆轴承未损坏RodBearingsAreUndamaged主轴承背面有黑色点蚀MainBearingBacksHaveBlackPitting曲轴的负载端损坏DamagetoLoadedEndofCrankshaft放电

ElectricDischarge可能的原因：PossibleCauses:机器上的电弧焊接ArcWeldingonUnit系统接地不良PoorSystemGround电流被其它电源放电ElectricCurrentbeingDischargedbyOtherSources电动离合器安装与接地不当ElectricClutchesImproperlyInstalledandGrounded磨蚀

Fretting外观/线索Appearance/Clues早期的轻度粘着磨损LightAdhesiveWearinEarlyStages轴承表面点蚀PittingOnBearingSurfaces生锈和腐蚀RustandCorrosion轴承背面和孔变色DiscolorationonBearingBackandBore磨蚀

Fretting可能的原因：PossibleCauses:孔径内轴承松动BearingLooseinBore固定盖螺栓的扭矩不正确IncorrectRetainingCapBoltTorque锥孔不圆BoretaperOutofRound轴承挤压力不足PoorBearingCrush请记住，极少量的磨蚀被视为正常现象。Remember,averysmallamountoffrettingisconsiderednormal.气蚀

CavitationErosion外观/线索Appearance/Clues轴承顶层的小块碎片残缺SmallPatchesofBearingTopLayerMissing碎片可能正好在轴承“高负载”区域前PatchesWouldbeJustBeforethe“HighLoad”AreaofBearing气蚀

CavitationErosion可能的原因：PossibleCauses:油质不好或等级错误PoorQualityOilorWrongGrade油位过低或过高OilLevelTooLoworTooHigh吸油侧漏气OilSuctionSideAirLeaks负载和速度条件过高TooHighLoadandSpeedConditions油的搅拌(空气含量高)ChurningofOil(HighAirContent)在发动机上的时间长HighHoursonEngine曲轴故障分析

CrankshaftFailureAnalysis弯曲故障BendingFailures扭转疲劳TorsionalFatigue弯曲故障

BendingFailure外观/线索Appearance/Clues与曲轴中心线呈90度断裂Breakage90degreestoCenterlineofCrankshaft断裂表面相当光滑，有明显的“浪状条纹”FairlySmoothBreakwithVisible“BeachMarks”从轴颈一侧到另一侧断裂FracturefromOneSideofJournaltotheOther弯曲故障

BendingFailures可能的原因：PossibleCauses:侧面负载过大ExcessiveSideLoads飞轮失去平衡FlywheelOutofBalance孔未对齐MisalignedBores轴承磨损BearingWear重复过载RepeatedOverloading扭转疲劳

TorsionalFailures外观/线索Appearance/Clues与曲轴中心线呈45度断裂Fracture45degreesfromCenterlineofCrankshaft轴颈周围的断裂螺纹FractureSpiralsAroundJournal几道“浪状条纹”SeveralSetsof“BeachMarks”断裂表面呈粗糙的阶梯形Rough,Step-LikeFractureSurface扭转疲劳

TorsionalFailures可能的原因：PossibleCauses:重复过载RepeatedOver