BM15LC型发动机曲轴拉瓦分析

Bearing Score Analysis of BM15LC Engine Crankshaft

通过宏观分析、扫描电镜、能谱分析、组织分析等方法对BM15LC型发动机曲轴拉瓦进行分析。结果表明:发动机曲轴及轴瓦呈现明显磨粒磨损特征,曲轴表面磨痕较浅,无块状剥落现象。轴瓦内表面合金层部分剥落,并嵌入许多铁质硬质颗粒,合金层无发黑变色现象。最初进入曲轴和轴瓦间隙的硬质颗粒很可能来源于机加工后未清理干净的缸体,是造成发动机曲轴拉瓦的根源。

The crankshaft bearings in BM15LC engine was analyzed by means of macroscopic analysis,scanning electron microscopy(SEM),energy spectrum analysis(EDS)and microstructure analysis.The results show that the engine crankshaft and bearing shells show obvious abrasive wear characteristics,the surface wear marks of crankshaft is shallow and no blocky exfoliation.The alloy layer on the inner surface of the bearing shells is partially exfoliated,and many hard iron particles are embedded.The hard particles that initially entered the gap between the crankshaft and the bearing bush are likely to come from the uncleaned cylinder block after machining,which is the source of the engine crankshaft pull bush.