GAS PERMEABLE METAL CASTING MOLD HAVING GAS COLLECTION VOIDS

摘要

ABSTRACTUnitary, rigid, self-supporting, gas permeable, low temperaturebonded, sand grain molds having peripheral side surfaces extending betweenvertically spaced upper and lower surfaces with mold cavity means spaced there-between connected to gate passage means having lower open ends exposed at saidlower surface, adapted to be filled with molten metal through the gate passagemeans by applying reduced pressure to the top surface of the mold while itslower surface with the gate passage means lower open ends are submerged inmolten metal, are provided with enclosed gas collection void means adjacent toand spaced from each of the mold cavity means, the gate passage means and theupper and lower mold surfaces for collecting gases from the cavity means andgate passage means during filling of the cavity means for controlled removalof gases from the void means through the upper mold surface by application ofreduced pressure thereto.