The welding pressure of erw pipe

Erw pipe  is a kind of welded steel pipe,welding pressure is a major factor, the two edges of the steel tube is heated to welding temperature in the extrusion under pressure to form a common metal that each crystal grain resulting from welding. Welding pressure affects the size of the weld strength and toughness. If the applied welding pressure is small, so that the edge can not be fully welded metal lamination, weld residual stress due to the small non-metallic inclusions difficult to discharge, reduce weld strength, after the force is easy to crack; width and thickness as the tube may the existence of tolerance, as well as welding temperature and welding speed fluctuations are likely to involve welding squeeze pressure changes.

Extrusion welding is generally by adjusting the distance between the squeeze roll control, you can roll around the tube with the squeeze-week difference to control. Pressure is too large to reach the temperature of the metal welding most of out, not only reduces the weld strength, and produce too much or take the burr inside and outside welding defects. therefore it should be based on different specifications in practice obtained corresponding optimal welding pressure.