METHOD FOR MANUFACTURING SEAMLESS METAL PIPES Russian patent published in 2023 - IPC B21B19/04 B21B19/06 B21B27/02 B21B37/16 

FIELD: pipe manufacturing.

SUBSTANCE: invention is related to a method for manufacturing the first seamless metal pipe with the first wall thickness and the second seamless metal pipe with the second wall thickness by using a three-roll inclined roll mill. The first stage of inclined rolling, the stage of changing the settings and the second stage of inclined rolling are carried out. During the first inclined rolling step, the first billet is rolled by means of an inclined roll mill. During the second inclined rolling step, the second billet is rolled by means of the inclined roll mill in the changed state. When the second wall thickness is smaller than the first wall thickness, the rolling angle of each of the inclined rolls is set to be larger than the rolling angle set for the first inclined rolling step. When the second wall thickness is larger than the first wall thickness, the rolling angle of each of the inclined rolls is set to be smaller than the rolling angle set for the first inclined rolling step.

EFFECT: occurrence of defects in manufacturing of pipes is prevented.

6 cl, 23 dwg, 8 tbl, 6 ex