METHOD FOR MAKING HOLLOW SPHERICAL PRODUCTS WITH THROUGH TUBULAR DUCT Russian patent published in 2000 - IPC

FIELD: plastic metal working, namely manufacture of hollow spherical articles with through duct such as stoppers of ball cocks and other members of lock fitting. SUBSTANCE: two shells are coaxially mounted on central rod of shaping tool. Inner shell has inner diameter equal to that of nominal opening of through duct. It allows to make spheres with through tubular duct. Edges of shell may be mutually joined by means of lap welded joint or shell blank is made with protrusion in its mean portion. Said protrusion is joined with inner surface of shell by lap welded joint. It allows to make spheres with thickened portion of wall designed for making blind groove in it. EFFECT: lowered labor and metal consumption, enhanced quality of products. 3 cl, 8 dwg, 1 exp, 1 tbl