The oil casing is short joint, causing this phenomenon due to internal mechanical failures such as roller or shaft eccentricity, or excessive welding power, or other reasons. As the welding speed increases, the tube blank extrusion speed increases. This facilitates the extrusion of the liquid metal layers and oxides that have been heated to the melt to the high quality weld. At the same time, increasing the welding speed can also reduce the heating time of the groove surface, so that the short circuit of the oil can be shortened and the heat affected zone can be narrowed.

On the contrary, not only the heat affected zone is wide, but also the thin layer of liquid metal main compound formed on the groove surface becomes thick, and large burrs are generated, which deteriorates the quality of the weld. However, at a certain output power, the cold welding speed cannot be increased without limitation. Otherwise, the heating on both sides of the billet groove will not reach the welding temperature, so that there is a defect or no welding at all.

For stainless steel, the short joint ripple coefficient of oil affects the formation of welds. Capacitance filtering reduces the ripple to less than 1%. When welding stainless steel, the frequency is usually 200 welds with good toughness and high frequency heat affected zone. . Usually, the inner and outer walls of the welded pipe are sprayed back from the welding area. Moderate, continuous foams are good at suggesting that the welding power is sufficient and the mechanical condition is uneven and the foam dark welding conditions are uneven and the weld quality is poor.