ERW steel pipe welding common defects

ERW pipe into the molding machine, the deformation of the pipe through an induction coil or contact welding angle, the induction coil current induced by the magnetic field is caused by the strip edge, the strip edge due to its resistance to heat resistance heating, heat extrusion Tape edge forming roller extrusion weld. Do not add high-frequency welding metal, in fact, forging welding. If the production control is good, the molten surface of the molten metal or oxide is not maintained. The heat-affected zone shapes like a drum because the edges of the strip enter the strip into the high-frequency current to generate heat from the edges of the strip at the sides and ends. The color of the HAZ is slightly darker than the base metal because the edges of the welded carbon steel strip heat diffuse and the cooled welded carbon is absorbed at the strip edge.


ERW pipe welding common defects
High frequency tube may be a variety of welding defects. There are many different names for each defect, and there are no accepted terminology. The names of the defects are given below, with another common name for the defects in the parentheses: 1 Inclusions (fired black oxide); 2 Pre-arc (white burn oxidation); 3 Lack of fusion (slotted); 4 Edge not Fusion (wavy edge); 5 lack of fusion in the center (cold welding center); 6 rod welding (welding); 7 cast welding (weld welding); 8 pores (pinhole); 9 jump welding. These defects are not the most common high-frequency welding defects.