Welding Process of SAWH Steel Pipe
Update:2016-12-15 View(s):2695 Keywords :
SAWH Steel Pipe will strip into welded pipe unit, the multichannel roll rolling, strip steel rolled up gradually, there is an open space form of round billet, adjust the quantity of the squeezing roller, make the weld gap control in 1 ~ 3 mm, and make joint flush on both ends.
1 If the gap is too large, resulting in a reduction in the proximity effect, the eddy heat is insufficient, the welding seam between the joint crystal is not fused or cracking.
2 If the gap is too small due to the proximity effect increases, excessive heat loss caused by welding, weld seam; or by extrusion, rolling after the formation of the pit, affecting the quality of the weld surface.
The two edge of the tube blank is heated to the welding temperature, and the common metal grains are formed to penetrate, crystallize and form a firm weld under the extrusion of the extruding roller.
If the squeeze pressure is too small, the number of common crystals is small, the strength of the weld metal is decreased, and the cracking is caused by the force.If the extrusion pressure is too large, will make the molten state of the metal is extruded weld, not only reduces the weld strength, and will produce a lot of internal and external burr, and even cause the defects such as welding seam.