What is the difference between straight steel pipe and spiral steel pipe?
Straight steel pipe and spiral steel pipe are all kinds of welded steel pipes. They are widely used in national production and construction. Straight steel pipes and spiral steel pipes have many differences due to different production processes. The difference between seam steel pipe and spiral steel pipe. The production process of straight steel welded pipe is relatively simple. The main production processes include high-frequency welding straight seam steel pipe and submerged arc welding straight seam steel pipe. The straight steel pipe has high production efficiency, low cost and rapid development. The strength of spiral welded pipe is generally higher than that of straight welded pipe. The main production process is submerged arc welding. Spiral steel pipe can produce welded pipe with different pipe diameter with blank of the same width, and can also produce welded pipe with larger diameter with narrower blank. However, compared with the straight pipe of the same length, the weld length is increased by 30 to 100%, and the production speed is low. Therefore, most of the smaller diameter welded pipes are straight seam welded, and the large diameter welded pipes are mostly spiral welded. In the industry to produce larger diameter straight seam steel pipe will use T-welding technology, that is, a short length of straight seam steel pipe will be butt jointed to meet the length of the project, the probability of T-weld straight seam steel pipe defects is greatly improved, and T-welding The welding residual stress at the joint is large, and the weld metal tends to be in a three-direction stress state, increasing the possibility of cracking.