Influence of strip edge shape on welding quality:
Shape and adjustment of staggered edges
Misalignment of plate edges (also known as lap welding) is an important reason for affecting welding quality. If the adjustment is improper, the misalignment will occur, which will reduce the effective wall thickness at the weld seam, and stress concentration will easily occur here
Torsion of welds:
Causes:
(1) The two welding side rolls have different heights, which can be corrected by adding or removing metal shims at the bottom or side of the horizontal roll frame.
(2) The roll positions of the two extrusion side rolls are asymmetric along the rolling center of the welded pipe, resulting in unequal force applied by the two extrusion side rolls on the pipe blank, causing the pipe blank to twist
(3) The bearing or guide plate of the finishing roll is damaged, which makes it impossible to control the torsion of the weld.
(4) The vertical direction of the guide roll position is adjusted too high, and only part of the guide roll pass contacts the billet, resulting in too little force applied to the billet, which can not control the roll torsion, or the guide roll or bearing is damaged.
