WELDED PIPE MANUFACTURING METHOD, AND WELDED PIPE MANUFACTURING DEVICE

摘要

In this method for manufacturing a welded pipe by bending a stainless steel strip having a thickness of 0.15 mm or more and 0.45 mm or less while conveying the stainless steel strip in one direction, to form a pipe, and welding abutting portions of the formed pipe by irradiating the same with a laser beam while applying compressive stress thereto by means of a set of squeeze rollers: the laser beam irradiation position is on the upstream side, in the pipe conveying direction, of the position of an axis of rotation of the squeeze rollers; the size of the spot diameter of the laser beam at the laser beam irradiation position is at least equal to 0.60 mm and at most equal to 1.2 mm; and an inert gas is blown from a gas nozzle onto the abutting portions irradiated by the laser beam.