齿轮传动水泵机械密封失效分析及改进

刘井年^1,2,李建文^1,2,申加伟^1,2,张志权^1,2,时胜文^1,2,陈国强^1,2

1.内燃机可靠性国家重点实验室,山东 潍坊  261061;2.潍柴动力股份有限公司，山东 潍坊  261061

摘要：针对柴油机齿轮传动水泵机械密封失效问题，对水泵进行失效模式机理分析、试验验证，得出导致水泵失效的主要原因为水泵转速波动大。为降低水泵转速波动，优化柴油机发火顺序、优化减振器匹配以降低曲轴转速波动，优化齿轮系以降低高压油泵、凸轮轴等附件振动冲击影响。试验验证表明，改进方案有效，可以采用转速波动量化评价齿轮水泵可靠性，为柴油机可靠性设计提供了理论依据。

关键词：齿轮传动；水泵；机械密封；转速波动

Failure analysis and improvement of mechanical seal of gear transmission water pump

LIU Jingnian^1,2，LI Jianwen^1,2，SHEN Jiawei^1,2，ZHANG Zhiquan^1,2，

SHI Shengwen^1,2，CHEN Guoqiang^1,2

1.State Key Laboratory of Engine Reliability，Weifang 261061，China；

2.Weichai Power Co., Ltd., Weifang 261061，China

Abstract：Aiming at the failure of mechanical seal of a diesel engine gear driven pump, the failure mode mechanism analysis and test are carried out. It can be found that the large fluctuation of pump speed is the main reason for the failure. In order to reduce the pump speed fluctuation, the optimized firing sequence and shock absorber matching are used to reduce the crank shaft speed fluctuation. Meanwhile，the vibration impact of high pressure oil pump, camshaft and other accessories can be reduced by optimizing gear system. The experimental results show that the improved scheme is effective, and the reliability of gear pump can be evaluated quantitatively by speed fluctuation, which provides a theoretical basis for reliability design of diesel engine.

Keywords:gear transmission; water pump; mechanical seal failure; speed fluctuation