METHOD OF SLEEVE ROLLING INTO PIPE Russian patent published in 2019 - IPC B21B17/00 

FIELD: technological processes.

SUBSTANCE: invention relates to hot rolling of pipes. Method of sleeve rolling into tube includes rolling of heated sleeve in caliber of rolls, axes of which are perpendicular to direction of rolling, with its deformation on mandrel, arranged in pass, subsequent reversal of rolls, cuffing of sleeve by 90° and rolling in reverse direction. Rolling is performed in rolls forming along their drums length several gauges of successively decreasing height, last two of which have equal height, wherein after each pass and reverse of rolls sleeve is transferred to adjacent gauge of lower height, with corresponding reduction of diameter of mandrel used in this pass, at that, deformation of sleeve in calibers is carried out on cylindrical mandrels, which are moved during deformation with speed lower than rolling speed, with subsequent return to initial position, and last pass is made in gauge height equal to height of previous gauge.

EFFECT: possibility of increasing drawing coefficient at rolling and improving quality of pipes.

1 cl, 2 dwg