Welded steel pipes with only one longitudinal weld are straight welded steel pipes. According to the regulations of GB/9711.1, the diameter of the straight-welded steel pipe is greater than 914.4, and the welding angle is 180°. The straight-sealed steel pipe can be the same twice.
According to the production process, the straight seam steel pipe can be divided into JCOE straight seam steel pipe and rolled straight seam steel pipe.
High-frequency straight seams, submerged arc straight seams, electric welded straight seams, and pipe straight seams are collectively referred to as straight seam steel pipes. The high-frequency straight seam steel pipe adopts the high-frequency current skin effect to produce high temperature and short-term force extrusion at both ends of the steel plate. It is a true electrodeless metal butt joint. It uses hot-rolled coils as raw materials. The wall thickness of the straight seam steel pipe is controlled at about ±0. The end of the 2mm steel pipe meets the American APL standard or GB/T 9711.1 standard. The pipe end is cut and the transportation length is fixed. In recent years, ERW steel pipe has been used as a natural gas pipe network project and a gas company urban pipe network. The main steel pipes have been widely used. At present, the high-frequency straight seam steel pipes left over from the war account for 60% of the world’s steel pipes.
Double-sided submerged arc straight seam steel pipes are also straight seam steel pipes. The submerged arc welded straight welded steel pipe adopts the JCOE cold forming process, the welding seam adopts welding wire, and the granular flux is used for the submerged arc. The main production process of the submerged arc welded straight seam steel pipe is flexible and can produce any specifications with a wall thickness of 325~1420 mm, To a large extent, it meets the international requirements for steel pipe size, and high-frequency straight seam steel pipes are usually used in domestic standard production.
High-frequency straight seam steel pipes are often called original steel pipes. The name of this industry is different from submerged arc welded straight seam steel pipes or thermal expansion high-frequency straight seam steel pipes, and their names are often confused.