METHOD FOR PRODUCTION OF HOLLOW PRODUCTS Russian patent published in 2009 - IPC B21K21/08 

FIELD: technological processes.

SUBSTANCE: invention is intended for production of hollow high precision pipe forged pieces with alternating profiles of external surface by cold radial compression. Method for production of hollow products with alternating profile of external surface includes production of initial billet, its mechanical processing with production of hollow billet, fixation of hollow billet between support and driving devices of radial clamping machine, deformation of hollow billet by means of radial clamping in holder installed in opening of hollow billet during length feed of the latter and final mechanical processing of deformed forged piece. Radial compression is done along the whole length in two operations, the first of which is carried out to produce semi-finished product with unstrained section. After the first operation of radial compression produced semi-finished product is turned by 180°, installed with unstrained section in direction of support device, and the second operation of radial compression is carried out.

EFFECT: high precision of products.

2 cl, 3 dwg