METHOD AND DEVICE FOR VACUUM AND PRESSURE CASTING

摘要

PURPOSE:To produce a thin-walled or large-sized product having high density and high strength by evacuating the cavity of a metallic mold prior to filling of a molten metal into the cavity and pressurizing quickly the molten metal after the filling. CONSTITUTION:A communication path 6 is shut off by a counter chip 5 and a vacuum pump is operated to evacuate the inside of the cavity 2. The molten metal 7 is then poured into a runner 8 and is charged into a sleeve 3 and in succession, the chip 5 is lowered to open the path 6. The molten metal 7 is vigorously admitted into the cavity 2 by the own weight thereof and the negative pressure in the cavity 2, by which the molten metal is quickly filled into the cavity. The chip 5 is risen after the filling to close a gate and pressurizing cylinders 9... are lowered to pressurize the molten metal 7 in the cavity. The evacuation is released upon solidification of the metal 7 and the casting product is taken out.