柴油机喷油器回油管密封失效分析

Failure analysis on seal of fuel injector return pipe of a diesel engine

为解决喷油器回油管密封失效问题,以实际使用过程中出现的喷油器回油管漏油问题为例,根据喷油器回油管的密封原理,采用动力学分析软件Abacus和网格划分工具Hypermesh对喷油器回油结构进行动力学分析,查找失效原因,并提出改进方案。分析结果表明,回油管与喷油器回油锥孔之间的接触密封面积小导致材料塑性变形和密封环线部分翘起是密封失效的原因。改进回油管结构,将回油管密封方式由线接触更改为面接触;同时改进喷油器与回油管的连接套结构,加强喷油器与回油管的紧固;将压紧锥面密封更改为过油螺栓加复合式密封垫圈的密封结构。对改进后的回油管进行500 h耐久试验,结果表明:回油管没有出现漏油故障,改进措施有效。

In order to solve the problem of fuel injector return pipe seal failure,taking the problem of oil leakage from the return pipe of the injector in actual use as an example,Abacus and Hypermesh are used for injector oil return structure dynamic analysis to find the cause of failure,and the improvement is proposed.The analysis results show that the sealing failure is caused by the small contact sealing area between the return pipe and the return oil cone hole of the injector,which leads to the plastic deformation and the partial warping of the sealing ring.For improvement,the line contact is changed into surface contact for pipe seal,and the connection sleeve is strengthened.After 500 h endurance test,the improved return pipe shows no oil leakage fault,which shows the improvement is effective.