气缸体水泵壳气缩孔的解决方案

Measure to Eliminate Shrinkage-blowhole Defect of Cylinder Block Water Pump Housing

介绍了一种带齿轮室和冷却水泵壳的四缸柴油气缸体铸件的结构,详细阐述了该铸件的生产工艺,对水泵壳高点周围3个位置出现的孔类缺陷进行了大量分析,初期从气孔角度分析和采取措施,均不能彻底消除该孔类缺陷。后期从气缩孔角度考虑,通过结构分析和数值模拟相结合的方法,将浇注系统各组元截面积增加14.8%~15.1%,浇注速度提高到12~14 s,顶面氧化物由2.1%下降为1.8%,彻底解决了最高点气缩孔问题,其废品率由最初的60%以上降至0,取得了很好的效果。

The cylinder block casting structure of 4-cylinder diesel engine having gear chamber and cooling water pump housing was introduced,its production method and process was described in detail.The reason causing hole type defects in 3 places around the water pump top was repeatly analyzed.Initially,considering the defects being blowholes and corresponding measures were adopted,however the defects could not be eliminated completely.Later,considering the defects being shrinkage-blowhole,by using structure analysis and numerical simulation,the every elements sections of the gating system were increased by 14.8%~15.1%,the pouring time was reduced to 12~14 s,the oxide on top surface reduced from 2.1%to 1.8%,thereby the shrinkage-blowhole defects on top surface had been eliminated thoroughly,the scrap rate was reduced from higher than 60%to 0,very good results were achieved.