The cross-sectional shape of the butt joint weld depends on the thickness of the welded body before welding and the form of the groove on both sides. When welding thicker steel plates, various shapes of bevels are made at the edge to facilitate penetration into the electrode or welding wire. Groove form has single-sided welding groove and two-sided welding groove. When selecting the groove type, in addition to ensuring penetration, consideration should be given to convenient welding, less metal filling, small welding distortion, and low groove processing costs.