Machinery for welding helical-seam pipe from metal strip

Abstract

Machinery for welding helical-seam pipe from metal strip. It includes a strip feed, a strip shaper, a seam welder, a pipe output, and a downstream pipe sectioner. The pipe sectioner has a cutter that moves back and forth axially, trimming sections of different lengths from the pipe as it rotates around its axis and leaves the machinery. The machinery also has controls that determine the welding gap between the section of the strip and the beginning of the pipe and how rapidly the pipe cutter moves along the pipe. How rapidly (v) the pipe cutter (47) moves along the pipe is controlled by three detectors. One detector (60 determines how rapidly (v.sub.b) the strip is traveling. Another detector (62) determines the strip-infeed angle (.alpha.) between the section (9) of strip and the axis of the pipe. A third detector, a camera (53), determines the axial deviation of the incision (54) over an angle (.beta.) to the pipe cutter at the circumference of the pipe.

Dependencies are inferred from the claim text.