发动机缸盖止推面烧结失效分析及解决措施

Analysis and Solution to Thrust Surface Sintering of Cylinder Head

某六缸增压直喷汽油机在试验过程中出现缸盖排气侧止推面烧结问题。为解决此问题,首先对可能造成止推面烧结的原因逐一进行排查,再通过仿真分析、试验验证等方法对问题原因进行确认。结果表明,缸盖后端结构强度差,后端轴承座润滑压力、流量偏低,且缸盖排气侧止推面与凸轮轴止推法兰接触宽度偏大,综合以上原因造成止推面烧结。针对止推面烧结问题,制定了提高缸盖结构强度、机油压力、减小接触宽度等方案。经试验验证,以上方案可以解决缸盖轴承端面烧结问题。

This paper shows a problem of thrust surface sintering occurred on a six-cylinder turbocharged direct injection gasoline engine on exhaust side of cylinder head. To solve this problem,firstly,it needs to check the possible causes which result in the thrust surface sintering gradually. Secondly, find out the real reason by means of simulation analysis and test results, and then put forward an available solution. Finally, as the results indicate, the structure strength of cylinder head at rear end is insufficient, the bearing surface at rear end lacks enough lubrication because of too low oil pressure and flow, the contact width between thrust surface and thrust flange of exhaust camshaft is too large. Based on these causes, this paper proposed there plans to solve the sintering problem：improve the strength of structure of cylinder head at rear end,improve the oil pressure and decrease the contact width. At last, we got obvious benefits from this kind of solution verified by test results.