改进浇注系统解决铸件缩孔缺陷

Improving Gating System to Solve Shrinkage Cavity Defects

介绍了HT250正时齿轮室铸件的结构特点及铸造工艺,分析了铸件缩孔缺陷的特征及形成原因,采取减小内浇道尺寸和减少一个内浇道的两种改进工艺措施,生产条件下齿轮室铸件均未发生缩孔现象。经过比对,最终采用减少内浇道的工艺,既解决了铸造缺陷,又因减少了部分横浇道和内浇道而节约了铁液,提高了工艺出品率,而且还减少了铸件该处的打磨工作量。

The configuration features of the gray iron timing gear chamber casting was introduced.The characteristics of the shrinkage cavity and its formation reason were analyzed.The shrinkage cavity defect had no more occurred again after reducing the dimensions of the ingates or removing one ingate.According to the result of two measures comparison it was decided finally to adopt the casting method with reduced ingates number.As the result,not only the casting defect was reduced,and the method yield rate was also increased due the iron melt saving brought by reducing of ingates number and shortening of the runner bar.