Spiral submerged arc welded steel pipes are a commonly used welding method in pipeline engineering. It is usually used for welding large-diameter steel pipes, such as oil and gas pipelines. The process of spiral submerged arc welded steel pipes involves pre welding spiral shaped steel plates inside and outside the pipe wall, and then fixing the steel plates together through the submerged arc welding process to form the steel pipe. The advantages of this welding method are high production efficiency, good weld quality, and suitability for large-diameter pipelines, making it widely used in engineering.