铸铁件的浇冒口一般可以用锤打掉。但在铸件表面上留下的部分仍须用机械加工的方法去除。可是,有些工件表面上允许有洼坑。因此,可以把浇冒口的形状加以改进(如图所示):将浇冒口置于工件上的小凹坑内,使它在折断的断口部分低于工件的表面, Cast iron parts of the riser generally can be destroyed by a hammer. However, the surface of the casting left behind parts still need to be machined to remove. However, some workpieces allow for potholes on the surface. Thus, the shape of the sprue can be improved (as shown) by placing the sprue in a small pocket on the workpiece so that it is below the surface of the workpiece at the broken fracture,