Incomplete penetration and lack of fusion defects

During the welding process, there is a tendency for some parts of the steel plate and welding electrode not to melt into each other. This results in defects such as incomplete penetration or lack of fusion during welding. Incomplete penetration defects mainly occur at the root of the welded joint, especially when the steel plate is relatively thick, making the incomplete penetration phenomenon more pronounced. In the welding process of spiral steel pipes, lack of fusion can occur in any part of the weld. It is evident that incomplete penetration and lack of fusion defects are major defects in the production of spiral steel pipes. These defects will lead to a sharp decline in the overall quality of the steel pipes, thereby affecting their normal use.