Electric resistance welding (ERW) refers to a group of welding process such as spot and seam welding that produce coalescence of faying surfaces where heat to form the weld is generated by the electrical resistance of material combined with the time and the force used to hold the materials together during welding.
ERW pipes means Electric Resistance Welded Pipes. ERW steel pipes and tubes are used. ERW steel pipes and tubes are used in various engineering purposes, fencing, scaffolding, line pipes etc. ERW steel pipes and tube are available in various qualities, wall thicknesses, and diameters of the finished pipes.
ERW pipes are available in lengths from single random to 120 feet depending on mill capability. ERW pipe is available with square ends or beveled for welding, threaded and coupled and victaulic grooved. Surface finish are available in black or bare, or with protective coatings.
For ERW pipes or tubes size 4 inch (10.2mm) OD and below, strip is fed into a set of forming rolls which consists of horizontal and vertical rollers so placed as to gradually from the flat strip in to a tube which is then allowed to pass the welding electrodes. The electrodes are copper disks connected to the secondary of a revolving transformer assembly.
ERW line pipe-- for the transportation of oil, natural gas and chemical materials
Standards: AP-5L PSL1/ PSL2 GB/T9711.1-1997 GB/T9711.2-1999Steel
ERW Casing pipe--petroleum and nature air exploration
Standards： API SPEC 5CT, SY/T5989
Materials ：H40 J55 K55
Structure and Mechanical Roundpipe and Tubing
Standards: JIS3466、JIS3445; ASTM A513; GB/T 6728-2002
Steel Materials: Carbon steel, Stainless, and low ally steel
Structure and Mechanical Square or Rectangular Pipe
Standards: GB/T3091 JIS G3452
Steel grade: Q215A、Q215B、Q235AB 、Q295AB、Q345AB