METHOD FOR MANUFACTURE OF HOLLOW BALLS AND OTHER ROTARY PARTS Russian patent published in 1999 - IPC

FIELD: plastic working of metals, in particular, manufacture of hollow rotary parts with profiled outer surface. SUBSTANCE: method involves placing mandrel inside hollow piece formed as thick-walled sleeve; positioning thick-walled sleeve between two rotating rollers having profile repeating profile of outer surface of part to be produced; moving one of rollers through predetermined distance or till reaching predetermined force in the direction of rotation of other roller and providing deformation; rotating rollers in one direction, with mandrel resting upon cutter provided with sleeve receiving recess positioned in opposed relation to forming surfaces of rollers; making belt with convex surface on mandrel, with diameter of belt being equal to or less than diameter of sleeve opening; squeezing part in respective device to eliminate ovality of produced part; providing sleeve ends with outer faces. Cutter has step for retaining mandrel during deformation process. EFFECT: increased efficiency and improved quality of produced part. 5 cl, 3 dwg