METHOD OF PRODUCING RETURN BENDS AND DEVICE FOR THEIR FORMING Russian patent published in 2010 - IPC B21D9/12 

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming, namely to methods and devices for producing tube return bends. Tubular billet is cut. Face chamfers are made on both sides of said billet and punch control point is produced perpendicular to tune lengthwise axis of symmetry. Billet is arranged in die guide sleeve. Billet is pushed in the gap between die hole working surfaces on mandrel floating in spinneret that repeats the geometry of band and has billet intake part. Stamped bend is remove from the stamping by the next billet. Proposed device comprises two semi-dies jointed to make spinneret with the help of retaining cartridge, guide sleeve, mandrel that floats in spinneret and guide sleeve. Said rigid one-piece mandrel repeats bend shape and has billet intake part.

EFFECT: higher efficiency, expanded performances.

2 cl, 3 dwg, 1 ex