METHOD FOR PREVENTING CRACKING OF CYLINDER HEAD IN INTERNAL-COMBUSTION ENGINE

摘要

PURPOSE:To prevent buried metal layers containing banked-up parts from cracking by providing a concaves among suction and exhaust valve seats and a fuel injection nozzle hole on a cylinder heat at the time of casting for injecting, banking up, and cooling heat-resisting metal in these concaves just after the casting. CONSTITUTION:Concaves 5 are grooved among a suction valve seat 2, an exhaust valve seat 3, and a fuel injection nozzle hole 4 on a cylinder head 1 at the time of the casting of the cylinder head 1. Heat resisting metal of nickel or the like is banked up by injecting or welding on the said concaves in a high temperature just after the cylinder head is taken out from its mold. Then, after the metal is cooled to give pressure strain, an ordinary machine work is applied to the heat-resisting metal layer 6 containing banks 6a for cutting or grinding. The heat-resisting metal is heaped up when the cylinder head 1 is in a high temperature. Consequently, concaves 5 and heat-resisting metal layers 6 are fused in a bridged and biting state, and prevented from coming off.