PRODUCTION OF CYLINDER HEAD FOR INTERNAL-COMBUSTION ENGINE

摘要

PURPOSE:To improve toughness and strength by chilling the surface parts in inter-valve parts and inter-valve and chamber parts to a specific depth and heating the chilled parts to a specific temp. thereby decomposing cementite. CONSTITUTION:Chillers 4 are installed to the parts of the casting mold corresponding to the respective surfaces of the inter-valve parts 10 between the suction valves and exhaust valves as well as the parts 11 between the suction valves and chamber and the parts 12 between the exhaust valves and chamber of a cylinder head. The surface parts in the inter-valve parts 10 and the inter- valve and chamber parts 11, 12 are chilled to at least >=0.2mm depth by casting. The chilled parts of the cylinder head taken out of the casting mold are heated to 900-1,050 deg.C to decompose the cementite to and to allow spheroidal or mass graphite to precipitate. The toughness and strength are thereby improved.