发动机曲轴箱内腔脉纹成因分析及对策

Veining Reason Analysis and Countermeasure in Inner Cavity of Engine Crankcase

介绍了发动机曲轴箱铸件的结构及生产中出现的铸件内腔脉纹问题,分析了曲轴箱油道内腔脉纹缺陷的形成机理,并采取多种措施进行改进,试验结果表明:(1)采用特种砂能解决脉纹问题,但显著增加铸件成本;(2)选择有机或无机防脉纹剂都会降低砂芯的强度,增加了铸件粘砂或烧结的风险,影响尺寸精度,造成铸件尺寸超差;(3)D381防脉纹涂料对铸件脉纹缺陷有着显著的抑制作用,并具有操作简单等综合成本上的优势。

The structure of engine crankcase casting and veining defect in casting inner cavity found in production was introduced,the formation mechanism of veining defect in oil channel of crankcase was analyzed,and multiple improving measures were adopted.Test results showed:(1)Using special sand could eliminate veining defect,however cost would obviously increased.(2)Using both organic or inorganic veining protection agents would decrease strength of sand core,and increase burning-on or sintering risk of casting and influence dimensional accuracy,cause casting dimension deviation.(3)D381 anti-veining coating had obvious inhibitory action on the veining defect,had simple operation and low composite cost.