Currently on the market sales of steel pipes, welded pipe in accordance with the manufacturing process can be divided into: straight seam welded steel pipe, spiral welded steel pipe, pipe coil butt welded steel pipe, welded pipe thermal expansion pipe, erw steel pipe.
Spiral steel pipe welding production process is simple, high production efficiency, low cost and rapid development. Spirally-welded steel pipes are generally higher in strength than straight-slot welded pipes. They can use narrower blanks to produce larger-diameter welded pipes, and they can also produce pipes of different pipe diameters using blanks of the same width. However, compared with the straight seam pipe of the same length, the weld seam length increased by 30 to 100% and the production price was lower.
Spiral welded steel pipe quality requirements: lsaw steel pipe is strip coil as the raw material is often warm extrusion molding with automatic double wire double-sided submerged arc welding process welded spiral welded steel pipe. Spiral welded pipes on the steel pipe market are mainly divided into: anti-corrosion spiral steel pipes. Corrosion-resistant steel pipes refer to steel pipes that are processed through anti-corrosion technology and can effectively prevent or reduce the occurrence of corrosion due to chemical or electrochemical reactions during transportation and use. Insulating spiral steel pipes and heat-insulating steel pipes refer to steel pipes that are guaranteed to meet or meet the requirements of working steel pipe inner temperature and surface temperature under the influence of different working environments and external media after being processed by thermal insulation technology.
Spiral steel pipe welding development direction:
(1) Produce large-diameter thick-walled pipes to improve pressure resistance;
(2) The design and production of new structure steel pipes, such as double spiral welded pipe, that is, the use of a steel pipe with half the thickness of the pipe to be welded into a double pipe, is not only higher in strength than a single pipe of the same thickness, but also does not cause brittle failure;
(3) To develop new steel grades and improve the technological level of the smelting process, and extensively adopt controlled rolling and residual heat treatment processes after rolling to continuously improve the toughness and welding performance of the pipe body;
(4)Strengthen the development of coated pipes, such as applying anti-corrosion coating on the inner wall of the pipe, not only can prolong the service life, but also can improve the smoothness of the inner wall, reduce the frictional resistance of the fluid, reduce the accumulation of wax and dirt, reduce the number of pigging, and reduce maintenance. cost.