气缸盖罩橡胶密封圈的密封性能分析

Analysis on Sealing Performance of Rubber Seal Ring of Cylinder Head Cover

利用有限元法对气缸盖-密封圈-气缸盖罩组合件进行螺栓预紧状态下的结构分析,得到了密封圈上的压力分布云图,发现密封圈主刃口的两个拐角处密封压力接近于零,不能有效地密封润滑油,与试验中该处漏油的实际情况一致。进一步的分析表明:漏油的主要原因是由于结构不对称,使得该位置缺少螺栓,导致密封压力接近于零。改进方案采取将气缸盖罩材质改为铝,将盖罩螺栓组中橡胶衬套改为减震弹簧等措施,大幅度地提高了最小密封压力,从而解决了密封问题。

The assembly of cylinder head,seal ring and cylinder head cover in pre-tightening condition were analyzed by finite element method.And the pressure distribution on the seal ring was obtained.It is found that the sealed pressure around the two main edge of seal ring is close to zero,which made the lubricant cannot be effectively sealed.This is constant with actual situation of oil spill in the same area during the test.Further analysis showed that the main reason for oil spill is due to structural asymmetry,which makes the location lack of bolts,leading the seal pressure close to zero.The improvement program is replacing cylinder head cover material with aluminum,replacing rubber bush of the cylinder head cover bolt group with damping spring.This improvement program substantially increases the minimum sealing pressure,so as to solve the sealing problem.