METHOD OF TUBE SCREW ROLLING AND MILL TO THIS END Russian patent published in 2011 - IPC B21B19/02 

FIELD: process engineering.

SUBSTANCE: invention is intended for increasing quality of hot-rolled weldless tubes from high-strength steels and alloys. Proposed method comprises tube billet heating, piercing it into barrel and rolling into tube in gage formed by working rolls, guide tool and piercing or rolling mandrel fitted on the rod. Barrel pierced, its front end is fed into gage for it to be rolled into tube, gage is readjusted for rolling by replacing the rod with mandrel and fitting said mandrel in gage by moving it axially relative to rolls without varying position of the latter. Proposed stand comprises feeding roll table, cross feed device, working stand with drive, front table with pusher and deflecting roll table. Two-section cross feed device is used, one section being provided with extractor and another one, a reversing overlapping extractor, being arranged parallel to rolling axis and provided with additional section arranged between device sections fitted with stationary stop with appliance to feed lubrication into barrel.

EFFECT: high-quality tubes, simplified design and control system, higher reliability and longer life.

2 cl, 4 dwg