Processing Technology of Spiral Steel Pipe

　　ASTM A53 Spiral Welded Carbon Steel Pipe is a strip coil as raw material, often temperature extrusion molding, automatic double wire double-sided submerged arc welding process welded seam steel pipe. The spiral steel pipe is fed into the welded pipe unit, rolled by the multi-way roll, the strip is gradually rolled up to form the circular tube with the opening gap, the pressure reduction of the squeeze roller is adjusted so that the gap gap is controlled at 1 ~ 3mm, and make the ends of the weld flush.

　　1. If the gap is too large, the adjacent effect is reduced, the eddy current is insufficient, and the joint between the welds is poor. 2. If the gap is too small is caused by the adjacent effect increases, welding heat is too large, resulting in weld burning; or weld by squeezing, rolling after the formation of deep pit, affecting the surface quality of the weld. After the two edges of the tube are heated to the welding temperature, the common metal grains penetrate and crystallize under the extrusion of the squeeze rollers to form a firm weld. If the extrusion force is too large, the metal in the molten state will be squeezed out of the weld, and if the extrusion force is too large, the weld metal will be squeezed out, Not only reduces the weld strength, and will produce a lot of internal and external burrs, and even lead to welding joints and other defects.