PIERCING INSTALLATION, MANDREL BAR AND METHOD FOR MANUFACTURING SEAMLESS METAL PIPE USING THEM Russian patent published in 2020 - IPC B21B19/04 

FIELD: technological processes.

SUBSTANCE: invention relates to piercing installation. Piercing installation comprises a plurality of skewed rolls arranged around the rolling line, a mandrel disposed on the rolling line between the plurality of skewed rolls, and a mandrel bar extending backward from the mandrel along the rolling line from the mandrel back end. Mandrel bar comprises rod body, channel for cooler formed inside rod body, cooling mechanism of inner surface located inside cooling zone in rod body, and the internal surface blocking mechanism located near the cooling zone on the rear side of the cooling zone. Cooling zone is located near the front end part of the mandrel bar. Cooling mechanism of inner surface provides outlet of cooler supplied from coolant channel under pressure outside from rod body to cool inner surface of hollow shell. Internal surface blocking mechanism ensures suppression of the contact of the cooler discharged under pressure outside from the rod body to the inner surface of the hollow shell after the hollow shell outlet from the cooling zone.

EFFECT: result is suppression of occurrence of temperature variations in longitudinal direction of hollow shell.

29 cl, 58 dwg