大型轮船曲轴推力盘开裂分析

船用柴油机曲轴推力盘在运行过程中推力面产生大量放射状裂纹,在随后修补裂纹过程中发生开裂失效。采用宏观观察、化学成分分析、力学性能测试、金相组织观察、透射电镜实验分析和断口扫描电镜分析等方法对断裂的推力盘进行了分析。结果表明:修补工作未完全消除的陈旧性裂纹,是推力盘产生崩裂的裂纹源;推力盘低温冲击韧性较低,脆性大,修补过程采用的感应加热方式引起了难以消除的的热应力,最终造成推动盘开裂。

Failure Analysis on Crankshaft Thrust Plate of Large Ship

A number of radial cracks were found in a crankshaft thrust plate of marine diesel engine during working. Then, the thrust plate fractured in the subsequent process of repair. Macro examination, chemical composition analysis, mechanical property test, metallurgical structure examination, TEM analysis, and SEM observation were used to study the fracture reason of the thrust plate. The results indicate that the original cracks formed during working were not removed in the repair process, leading to the subsequent propagation of cracks;In addition, the higher brittleness of the material and the thermal stress caused by improper induction heating in the repair process promoted the cracking failure of the thrust plate.