以往计算慢速压射行程都是从“慢速压射行程是从冲头起动运行至金属液充满压室和浇注系统为止的行程”这一观念出发的。其理由是:如果在冲头的快速压射阶段开始时,压室和浇注系统内还没有填满金属,那么,由于在快速压射阶段中,冲头以很大的速度运行,因而金属液的流动及其颤动,就会卷入压室和浇注系统中残余的气体;金属液和气体两相混流,一起进入型腔,从而造成铸件的气孔。但是,这只是矛盾中的主要 In the past, the calculation of the slow injection stroke was based on the concept that “the slow injection stroke is the stroke from the start of the punch operation to the filling of the molten metal into the pressure chamber and the casting system”. The reason for this is that if the press chamber and gating system are not yet filled with metal at the beginning of the rapid shot-injection phase of the punch, then since the punch runs at a very high speed during the rapid shot-injection phase, the molten metal Of the flow and its vibration, it will be involved in the pressure chamber and the residual gas in the casting system; metal liquid and gas two-phase flow, together into the cavity, causing the pores of the casting. However, this is only the main contradiction