气门间隙对进气门工作可靠性的影响

葛坚，崔彦军，赵志强，张青锋，李治明，向宝山

河南柴油机重工有限责任公司，河南 洛阳  471039

摘要：为解决某船用发动机进气门断裂故障，排查零部件的技术因素、装配过程、强度分析、气门检查等,确定故障原因；采用配气机构动力学仿真和有限元分析验证故障原因，提出改进措施。结果表明：进气门断裂的主要原因为进气门间隙过大，造成进气摇臂与进气门之间的接触力及进气门落座力增大，导致气门锁夹下边缘和阀杆下部应力集中，安全系数下降；气门间隙调整需在气缸位于压缩上止点时进行，并按照发火顺序调节其余各缸气门间隙，提高气门工作的可靠性。

关键词：高速发动机；进气门断裂；断口分析；气门间隙

Influence of valve clearance on the reliability of intake valve operation

GE Jian，CUI Yanjun，ZHAO Zhiqiang，ZHANG Qingfeng，LI Zhiming，XIANG Baoshan

Henan Diesel Engine Industry Co.,Ltd., Luoyang 471039,China

Abstract：In order to solve the problem of intake valve fracture in a marine engine, the technical factors, assembly process, strength analysis, and valve inspection are investigated to determine the cause of the fault. Dynamic simulation and finite element analysis of the valve train are used to verify and improve the problem. The results show that the main reason for the fracture of the intake valve is the excessive clearance of the multicylinder intake valves, which increases the contact force between the intake rocker arm and the intake valve, as well as the seating force of the intake valve, resulting in stress concentration at the lower edge of the valve lock clamp and the lower part of the valve stem, the safety factor decreases. The adjustment of the air valve clearance needs to be carried out when the cylinder is at the top dead center of compression, and the air valve clearance of other cylinders should be adjusted according to the firing order, which can improve the reliability of the intake valve.

Keywords:high speed diesel engine;inlet valve fracture;fracture analysis;air valve clearance