Failure Analysis And Prevention For Diesel Engine Crankshaft

The material, geometrical size and figuration technics process of WD615 crankshaft are introduced in this thesis. The crankshaft after nitridation is tested and analyzed. Meanwhile, the fatigue strength of crankshaft is tested and calculated for the reason of failure mode of the crankshaft provided by consumers'feedback.This paper has done finite element analysis of WD615 crankshaft, which accords with the actual situation, and then checkout the fatigue strength of crankshaft. Also, the fatigue experiments are done to validate the results of analysis and calculation.The broken type, broken position and plastic deformation degree of the failed crankshafts which are back from market are checked and classified according to their different failure positions so that the failure rule can be found. The following rule finds that bush melting or oil lack may cause the crankshaft failed passively. Other factors such as bad manufacture or assembly may also cause the crankshaft failed. Then appropriate preventions are made: enhancing propaganda in order to ensure correct operation and maintenance in time; screwing down the bolts while mounting absorber; machining round corner correctly.The statistics and summarizing to failed crankshafts can supply actual data for crankshaft design and technics improvement in our company. Preventions which are put forward in this article are in favor of decreasing crankshaft accident, continuously improving product quality and enhancing market competitive power.