Shell Molding Process

Shell Molding Process Points : Shell Molding Casting Process Shell molding is a metal casting process in manufacturing industry in which mold is a thin hardened shell of sand and thermosetting resin binder, backed up with some other material. Shell mold casting is mainly proper for steel castings under 20 lbs; though approximately any metal that can cast in sand can cast by the shell molding process. Moreover much larger parts have been manufactured by shell molding. Usual parts manufactured in industry using shell mold casting process contain cylinder heads, bushings, gears, connecting rods, camshafts and valve bodies. Shell molding process in which sand mix by a thermosetting resin is allowed to come in contact by a heated pattern plate (200 °C), this cause a skin (Shell) of about 3.5 mm of sand/plastic mix to stick to the pattern. Then shell is removed as of pattern. Cope and drag shells are kept in flask by necessary backup material and molten metal is pouring into mold. Shell molding process can make difficult pails by good surface finish 1.25 m to 3.75 um, and dimensional tolerance of 0.5 00. Good surface finish and good size tolerance reduce need for machining. The process on the whole is fairly cost of use due to reduced machining and cleaning costs. The materials that can use by this process are cast irons, and aluminum and copper alloys.