Countergravity casting apparatus and method

摘要

In vacuum countergravity casting a melt into a mold sealingly engaged to a vacuum container by an elastomeric sealing gasket, the sealing gasket is isolated from the heat of an underlying source of the melt and from contact therewith during casting by substantially binderless refractory particulates, such as loose foundry sand, held in a particulate-receiving space in the container about a lower, melt-engaging portion of the mold by a negative differential pressure established between the inside and outside of the particulate-receiving space.