本文主要根据冒口系统的补缩作用,提出防止收缩缺陷的措施。一、可锻铸铁件的铸态收缩在铸型和铸件尺寸一定的情况下,化学成分是决定可锻铸铁件的铸态组织和凝固过程的一项基本因素。可锻铸铁一般的化学成分(%)为:C2.4～2.7;Si1.5～1.9;Mn0.4～0.75;S<0.25;P<0.2;Cr≤0.06。可锻铸铁的铸态组织为珠光 In this paper, mainly based on the role of riser system of shrinkage, proposed measures to prevent shrinkage defects. First, the malleable cast iron shrinkage In the case of molds and castings of a certain size, the chemical composition is to determine the malleable castings of the as-cast structure and solidification process is a basic factor. The general chemical composition (%) of malleable iron is: C2.4 ~ 2.7; Si1.5 ~ 1.9; Mn0.4 ~ 0.75; S <0.25; P <0.2; Cr≤0.06. Malleable cast iron as pearlescent organization