如图1所示的离合器壳体,是我公司采用消失模铸造工艺生产批量较大的一类离合器壳体铸件。其材我公司从2002年底开始采用消失模工艺生产离合器壳体铸件,2010年离合器壳体铸件出现缩孔缺陷,全年缩孔废品率约为4%,占到全年废品率的 As shown in Figure 1 clutch housing, is my company using EPC technology to produce large quantities of a class of clutch housing castings. The material I started from the end of 2002 the use of EPC technology to produce the shell castings, clutch housing casting shrinkage defects in 2010, the annual rate of shrinkage cavity shrinkage of about 4%, accounting for the full year scrap rate