Advantages of erw steel pipe compared with seamless steel pipe are following below:
A) High dimensional accuracy. ERW steel pipe diameter and wall thickness than the seamless steel pipe deviation is much smaller, because the strip rolling and pipe forming easy to control, so high dimensional accuracy.
B) Good mechanical properties. As the ERW steel pipe with easy control of rolling, with the welding technology and on-line heat treatment technology, the performance of the weld can be controlled, so straight seam welded steel pipe elongation than seamless steel pipe 8% -10% higher, which Is because the straight seam electric-welded pipe carbon content of less than 12% lower than the seamless tube.
C) ERW steel pipe with high concentricity, uniform wall thickness. Weld after heat treatment, microstructure uniform, with a strong ability to collapse collapse.
D) As the extension of the steel is good, straight seam sewing machine sister pipe flattening test is better than seamless.
E) The impact toughness of ERW steel pipe is higher than that of seamless steel pipe.
F) Longitudinal resistance welded pipe is not welded into the dissimilar metals, but also undergo a rigorous on-line heat treatment, so the basic performance of the weld and material properties.