METHOD OF TUBE PRODUCTION AT CONTINUOUS TUBE WELDING UNITS Russian patent published in 2012 - IPC B21C37/06 

FIELD: process engineering.

SUBSTANCE: proposed method comprises using strip with width increased by amount of its pull-down over width in strip deformation, butt welding of separate coil strip ends into continuous strip, and subjecting strip to alternating deformation. Increase in adjustable range of control over amount of drawing is ensured by arranging three-roller banding device with idle rollers between multi-roller bending device and pulling device, wherein gap between extreme rollers exceeds two thicknesses of the strip. Diameter of central roller is smaller than that of extreme rollers. The angle rolled strip covers central roller at makes 180° Note here that central roller is pressed together with strip against extreme rollers by strip tension. Strip is deformed by drawing it with pulling device through multi-roller and three-roller bending devices. Strip thickness is measured before deformation. Total forming of strip in both bending machines is defined to be controlled at the level of magnitude equal to relation of strip measured thickness to preset minimum tolerable thickness by varying total strip bending angles in multi-roller bending device with limiting its drawing by value that provides for its pull-down over width not exceeding maximum tolerable value.

EFFECT: higher precision, reduced metal input.

2 cl, 1 dwg, 1 tbl