REMAINING STRESS IMPROVING APPARATUS FOR TUBE AND METHOD FOR ADJUSTING THE REMAINING STRESS IMPROVING APPARATUS

摘要

Provided are a remaining stress improving apparatus for a tube, for adjusting irradiation position with excellent repeatability without being affected by core shift of an optical fiber, and a method for adjusting such apparatus. In the remaining stress improving apparatus, a laser head (5) is provided with a rotating holding mechanism (9) for holding an optical fiber (6) to be rotated in the circumference direction, and when the position of the intensity peak of the laser beam from the fiber (6) in the axial direction of a piping (2) is shifted from the center of an irradiation profile, the holding position of the optical fiber (6) in the circumference direction is adjusted by the rotating holding mechanism (9) to eliminate the shift or to minimize the influence.