球铁飞架缩孔原因分析及解决对策

Reason and Countermeasures of Shrinkage of Ductile Iron Bracket

分析了球铁飞架铸件时常出现缩孔的原因,用排除法确定了冒口及冒口颈的参数设计不合理是根本起因。重新计算了冒口及冒口颈的各项参数,按新参数生产的铸件没有再出现集中缩孔缺陷。指出严格的操作并不能弥补铸造工艺设计的不足,而铸造工艺设计的合理化在一定程度上却可以弥补操作的波动。

The reason often causing shrinkage defect in ductile iron bracket castings was analyzed. It was confirmed by using Factors Excluding Method that the improper parameters of both the feeder and its neck were the ultimate reason causing shrinkage defect. Therefore the parameters were changed, and the castings produced with new parameters have not any more shrinkage defect. It was pointed out that the improper casting method design can＇t be offset by strict operation, however, the fluctuation of operation can be offset in some degree by the proper casting method design.