Black steel pipe used for conveying fluid and solid, not only to exchange heat, manufacturing machinery parts and container, it is also a kind of economic steel. With black steel pipe manufacturing space truss structures, pillar and mechanical support, can reduce light weight, saving metal 20 ~ 40%, and can realize the mechanization of factory construction. Black steel pipe manufacturing highway Bridges not only can save steel, simplify construction, and can greatly reduce the area of the coating layer, save investment and maintenance costs.
So, any other types of steel cannot completely replace steel tube, but the steel tube can replace part of the profile and bar. Black steel pipe to the national economic development and improvement of quality of human life, is far better than the other steel products. From People's Daily appliances, furniture, water supply and drainage, gas supply, ventilation and heating facilities to various kinds of agricultural machinery equipment manufacturing. The development of underground resources, defense and aerospace used guns, bullets, missiles, rocket is inseparable from the steel tube and so on.
Because of the steel tube is closely connected with human life and production activities, production technology of black steel pipe industry has developed rapidly, not only bring forth the fresh, Also black steel pipe production in iron and steel industry occupies an irreplaceable position. Black steel pipe and welded pipe, is to use steel plate or steel strip after crimp molding made of welded steel pipe. The technology of producing black steel pipe is simple and the production efficiency of it is high, but the general strength of the black steel pipe is lower than that of the seamless steel tube. This can increase the profiles of the black steel pipe. The seamless steel tube is instead in the field. The welded steel pipe formed according to the weld seam welded pipe and the spiral welded pipe.
The technology of straight seam welded pipe production is also simple, and with high production efficiency, low cost and rapid development. The strength of the straight seam API steel pipe is lower than that of the black steel pipe, which uses a narrow billet production with a smaller diameter welded pipe. Also you can adopt the production of the same width of billet with different pipe diameter welded pipes. If compared with the same length of straight seam welded steel pipe, its length is 30~100 percent and its production speed is low. As a result, a small diameter black steel pipe is mostly with straight seam welding, large diameter welded pipe for the most part adopts spiral welded. These profiles of black steel pipe are used for transporting oil, gas, air, water, heating steam and so on.