METHOD FOR MAKING VALVE FOR INTERNAL COMBUSTION ENGINE (VARIANTS) Russian patent published in 2003 - IPC

FIELD: plastic metal working, possibly manufacture of valves of internal combustion engines. SUBSTANCE: in first variant of invention blank is placed in die in such a way that it protrudes out of die by value whose length exceeds blank diameter no more than by three times. Then valve disc is formed due to end expansion of protruded portion by punch mounted with inclination angle equal to 0.5 - 15 degrees relative to die. In second variant of invention blank is placed in die having opening whose diameter is equal to that of valve stem and central cone surface. Disc of valve is formed by end expansion of blank by means of punch inclined relative to die axis. At process of end expansion of valve, stem is pressed out to opening of die. EFFECT: valve with metal microstructure having uniform distribution of fibres in parallel relative to contour of valve disc. 4 cl, 1 dwg, 2 ex