Classification of welded steel pipe

1, High frequency welded steel pipe features: tubular good, uniform thickness, internal and external burrs produced by the welding tool calibrating the appropriate online through strict control of non-destructive testing of weld quality, high degree of automation, low production costs. But relatively thin wall thickness, diameter is relatively small, usually no more than a wall thickness of 12mm, diameter generally does not exceed 610mm, particularly suitable for the production of steel tube truss structure.

2, LSAW pipe features: welding under static conditions, high weld quality, short welds, the probability is very small defects. By expanding full-length steel tubular good, precise size, wide range of pipe wall thickness and diameter range, the diameter range up 406-1829mm, wall thickness range up 6.0-60mm, high degree of automation, Compared to seamless steel, it is lower production costs, for buildings, bridges, dams, offshore platforms and other steel bearing with columns, large span structures as well as wind and seismic requirements for electrical tower mast structure.

3, Spiral submerged arc welded pipe features: spiral weld line distribution, long welds, especially under dynamic conditions is in the welding, the weld had a chance to cool and left the molding point, easy to produce welding hot cracking. Direction parallel to the weld crack, a certain angle the axis of the steel pipe, typically between  30-70 °. This angle is just consistent with shear failure angle, so the bending, tensile, compressive and torsional performance is far better than LSAW pipe welding position and because restrictions, saddle ridge seam and fish the impact beautiful. In addition, the construction process, intersecting line pipe weld spiral welded parent node of fragmented spiral seam, a greater welding stress, thus greatly weaken safety performance components, and therefore efforts should be strengthened spiral welded non-destructive testing of welds, ensure the welding quality, otherwise important occasion not to use steel spiral submerged arc welded pipe.