Submerged arc welding is commonly used to manufacture LSAW steel pipe and SSAW steel pipe, and those two kinds of steel pipe are widely used in various kinds of production and transportation activities. The main feature of submerged arc welding is that the weld and the arc area is protected from environmental contamination by the application of a granular flux which is fusible. The weld pool is protected by a blanket of flux. So that area is actually submerged under that flux. When temperature rises and molten the flux becomes conductive. And thus this creates a path for electron flow between electrode and workpiece. SAW or Submerged Arc welding can be done by manual procedure or automatic process. But it can be done by semi-automatic process where welding gun is hold by hand.