METAL MOLD

PURPOSE:To maintain metal molds at a required temp. without requiring any special apparatus for control, by charging a latent heat type heat accumulating material having a m.p. approximately equal to the temp. to be maintained in the body of the metal molds in said body. CONSTITUTION:When molten metal is charged into a body 11 of metal molds through a sprue 12, the molten metal fills a runner 13, a cavity 14 and a flow- off 15 and the temp. of the body 11 is going to rise. A heat accumulating material 17 melts and absorbs large quantity of latent heat while the material 17 is in a coexistence state of solid and liquid, then the temp. rise of the body 11 ceases until the material 17 melts down completely, and the body is maintained at the m.p. temp. The complete melting of the material 17 is thus prevented by the quantity of the heat held by the molten metal to be charged into the body 11 by setting the amt. of the material 17 to be charged into the body 11 suitably, whereby the body 11 and the material 17 are maintained always at the m.p. temp.