| 摘要 |
PURPOSE:To improve the quality of a welded part and the productivity by joining thick steel plates without leaving spaces, assembling them in the columnar shape of a flat cross section, irradiating these joined surfaces with beam from the outside and welding the joined surfaces. CONSTITUTION:Four thick steel plates 1a, 1b, 1c, 1d are joined without leaving spaces, assembled in the columnar shape having a closed section, the outer faces of four corner parts are chamfered further in the directions orthogonal to the joined surfaces, then, beam welding is performed. from the outer faces of four corner parts to the joined surfaces Further, backing strips 3 are attached to the back sides of the joined surfaces so that the steel plates in the shape of diagonal lines are prevented from being damaged by the laser beam penetrating the welded surfaces. Electronic beam welding, laser beam welding or any other beam welding work well as beam welding. Consequently, a square steel tube column can be manufactured by beam welding irrelevant to plate pressure and the productivity, the quality of the welded part and the apperance of a product are improved. |
