曲轴疲劳试验标准Crankshaft

AVL LIST GMBHNew Engine FamilyDate:08.05.2003AVL CONFIDENTIALCrankshaft Fatigue Test ProcedureChery NEF1 – 1,6L 4V CBR VVTWritten byApproved byBenjamin WestClaus KnorzMech. DevelopmentManager Mech. DevelopmentAVL LIST GMBHNew Engine FamilyDate:08.05.2003AVL CONFIDENTIAL1ObjectiveThe main objective of this test is to assess the fatigue strength of the crankshaft. The test iscarried out on a dedicated fatigue test machine, which is usuallyhydraulicallydriven andsimulates the relevant loads on the crankshaft of a running engine.The fatigue tests are regarded mainlyas a verification of the production process of thecomponents. Therefore the specimen should be ideallyfullyproduction level. In an earlyphaseof an engine development program it might be useful to perform a preliminarytest program withprototype components.The tested areas are the crankshaft fillets, where different methods are in use to increase thebending fatigue strength, i.e. rolling and hardening. The calculation (1) asseses the fatiguestrength of the crankshaft during engine operation using EXCITE software. The lowest safetyfactor was calculated to be in the crank pin fillet and was due primarilyto the bending forcespresent. This means then that bending load condition should be used for fatigue analysis.The fatigue strength evaluation will also be supported bymetallographic examination of the filletareas of at least two pins. Additionallymicrohardness measurements mayalso be specified todetermine the hardness profile within the fillet sections.2Test PreparationThe dominant load according to calculation (1) during engine operation is bending withsignificantlyless influence from the torsion loads. The fatigue assesment will therefore onlyconsider bending loads.2.1Specimen Preparat...