| 摘要 |
FIELD: plastic metal working, namely production of coils and branch pipes of tubular blanks by bending at acting upon them by cross and longitudinal efforts. SUBSTANCE: method comprises steps of bending tubular blank by cross efforts normal relative to its axis, selecting predetermined distance between acting lines of adjacent efforts directed one opposite to another. It allows to reduce degree of wall thickness difference and out-of-roundness until value less than 5 % and to eliminate step of preliminary heating of blank up to high temperature with use of sand and melt glass. EFFECT: enhanced efficiency. 4 dwg, 1 ex |
