孙琛媛^1,2，刘召伟^1,2，宋树峰^1,2，郭庆元^1,2

1.滨州渤海活塞有限公司，山东 滨州 256602；

2.山东省发动机活塞摩擦副重点实验室，山东 滨州 256602

摘要：为了降低某柴油机铝活塞降低摩擦磨损，在不更改活塞刚性的基础上，通过优化销孔偏置设计、降低活塞环高度、更改裙部型面等措施对活塞进行优化改进。利用动力学分析软件对优化前后活塞进行对比，模拟结果显示活塞的机油耗和漏气量明显降低，敲击动能和摩擦平均有效压力降低。通过倒拖法和可靠性试验验证改进措施的有效性。结果表明：销孔向主推力侧偏置0.5 mm，配合减小活塞环环槽宽度、优化裙部形线时，活塞摩擦平均有效压力最小，可以有效降低活塞的摩擦磨损。

关键词：活塞；摩擦磨损；有限元分析；动力学分析

Abstract: In order to reduce the friction and wear of a diesel engine piston without changing its stiffness, improvements have been conducted including optimizing pin bore offset, lowering rings’ heights, optimizing side profile. Dynamics analysis was used for comparison of piston proposals before and after these optimization. The simulated results show that the oil consumption, blow by, knocking energy and average friction pressure have been reduced, which have been verified by dynometer test and reliability test. It could be found that the average friction pressure is the lowest when offset of pin bore is 0.5mm to thrust side, with ring groove width reduced and side profile optimized, which can eventually reduce the piston’s friction and wear.

Key words: Piston; Frictional and wear; Finite element analysis; Dynamics analysis