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

Steel pipe piles are widely used in various situations such as supporting piles and friction piles. Especially when it is used as a supporting pile, it can be fully driven into a relatively hard supporting layer, so it can exert the bearing effect of the strength of the entire section of the steel.T

In long-distance pipeline transportation projects, pipeline welding is often the most important processing step, so the choice of welding joints and welding methods during processing will become more important. In general welding operations, fixed welding, rotary welding, and prefabricated welding a