What are the factors that cause horizontal lines in spiral seam submerged arc welded steel pipes?First of all, it may be due to the stress of the spiral seam submerged arc welded steel pipe. That is, the residual stress and welding stress after the steel pipe is formed.Secondly, due to the presence

Horizontal fixed welding of thick-walled stainless steel pipe:Stainless steel pipe is a kind of hollow long steel, used as pipelines for conveying fluids, such as oil, natural gas, water, gas, steam, etc. Stainless steel tubes are lighter when they have the same bending and torsion strength. They ar

1. The surface of the plated parts is not clean⑴The surface of the plated parts contains paint, grease, and welding iron; it can be polished or prepared with related solvents for scrubbing.⑵Iron oxide; lack of pickling; continue pickling.2. Pickling and operation:⑴ Under and over pickling. Under-pic

1. Visual inspection.The visual inspection of welded joints is a simple procedure with a wide variety of inspection methods. It is an important part of finished product inspection, mainly to find welding surface defects and dimensional deviations. Generally, the test is carried out by visual observa