Mastering the bending and drawing of skelp in the line of a 73-219 electric-welded pipe mill at the Severskii Pipe Plant

Results are presented from tests performed at the Severskii Pipe Plant on the bending and drawing of unpickled hot-rolled skelp in the line of electric-welded pipe mill (EWPM) 73-219. The skelp is bent in a bending-tensioning device with seven undriven work rollers and support rollers and is withdrawn from it by the pinch-roller stands, forming stands, and sizing stands of the EWPM. The work rollers are durable (having a service life of more than 1000 h). The degree of elongation of the skelp is controlled in relation to its thickness by using the rollers to change the depth of the bends. The bending-drawing operation eliminates curvature of the skelp and reduces metal consumption by 15–20 kg/ton tubing. The savings in rubles is 13.2 times greater than the cost of introducing the technology, including the amount spent on electric power.