METHOD FOR THE PRODUCTION OF COLD-FORMED ELECTROWELDED PIPES Russian patent published in 2021 - IPC B21C37/08 

FIELD: pipes.

SUBSTANCE: invention relates to the manufacture of electrically welded cold-deformed pipes from low-alloy steel of a regulated composition. The pipe of the original size is subjected to heat treatment and preliminary plastic deformation, carried out in at least one pass of short drawing to obtain a pipe of an intermediate size. Normalization of the intermediate size pipe is carried out at a temperature of 900±20°C with a holding time of at least 7 minutes. The final plastic deformation is carried out to obtain a pipe of a given size. When carrying out preliminary and final deformation, a lubricant is applied to the pipe surface in the form of saponification. In this case, the degree of final plastic deformation is regulated.

EFFECT: invention makes it possible to increase the strength properties of a welded cold-worked pipe with the simultaneous achievement of a set of required mechanical properties.

1 cl, 4 tbl