HOLLOW POPPET VALVE AND ITS MANUFACTURING METHOD

摘要

A hollow poppet valve and its manufacturing method, wherein measures are taken to prevent welding heat from affecting face surfaces and stresses from concentrating on welded parts so as to provide an excellent high strength to weight characteristic, the hollow poppet valve comprising a fillet area (14) open in flare-shape formed integrally with one end of a cylindrical stem part (12) and a cap (16) welded integrally with the open edge part of the fillet area (14), wherein only the open edge part of the fillet area (14) is formed thicker than the other areas, a face surface (15) is formed on a thicker wall part (30) so as to suppress the hardness of the face surface (15) from lowering by a cap welding heat and avoid the concentration of stresses on a welded part (20) for improvement in the high strength to weight characteristic.