METHOD FOR MAKING T-PIECE FROM TUBULAR BLANK Russian patent published in 1998 - IPC

FIELD: plastic metal working, namely forming parts of tubular blanks in airplane manufacture, ship building and other allied industry branches. SUBSTANCE: method comprises steps of cutting out oval opening in blank, locally heating edge of opening and flanging it by pushing cone punch; in flanging zone on inner surface of tubular blank setting technological washer made of metal having low friction factor relative to punch surface and diameter of inner opening less than that of flange by value equal to thickness of wall of tubular blank. EFFECT: enhanced quality of T-pieces. 2 dwg