基于某型国六柴油机气门导管异常磨损问题的分析及改进

Analysis and Improvement Based on a Certain Type of CN-6 Diesel Engine Valve Guide Abnormal Wear

针对某型国六柴油机在耐久实验中出现漏气量高的问题,对整机的零部件进行拆解发现排气门导管异常磨损,通过对实验排气门外观、尺寸的分析,对排气门导管外观、材料、硬度、金相组织、磨损、内壁的扫描观察等分析,对排气门温度场实验分析,得出气门导管是因温度过高使热硬度下降,从而导致排气门与气门导管不匹配,使气门导管出现异常磨损。在此基础上提出优化水套结构,改善气门导管材料来解决这个问题,最终经过台架耐久试验验证了这一方案。

Based on a certain type of CN-6 diesel engine serious air leakage in durability experiments,this paper disassembled the parts of the engine and found the exhaust valve guide seriously worn.Through the analysis of the experimental exhaust valve appearance,size and appearance of the exhaust valve guide,the material,hardness,microstructure,wear,such as scanning analysis of the lining,and experimental analyzing the exhaust valve temperature field it is concluded that the decreased heat hardness of valve guide is due to the high temperature,thereby the exhaust valve and valve guide does not match and abnormal wear and tear of the valve guide.On the basis of the optimization of water jacket structure,improving the valve guide material is put forward to solve this problem,which finally is validated through bench endurance test.