Check whether the curling edge is normal and uniform, and use the curling edge measuring instrument to measure its width within the specified size range; after cutting the curling edge, check that there should be no contamination at the bottom of the curling edge and the welding interface of the pipe; check the welding interface at the bottom of the curling edge There should be no cracks caused by insufficient fusion and insufficient fusion; bend the curling edge to the back, and no cracks caused by insufficient fusion should appear; check that the pipes at both ends should be aligned on the joint.
