There are various of cold forming selectional steel. Differing from their shapes of sections, they are open, semi—close and close. And the main products are cold bending channel steel, angle steel, Z type steel, cold bending corrugated steel plate, square tube, rectangular tube, electric welding special-shaped steel pipe, curtain door and so on. Generally, the thickness of cold forming selectional steel produced are below 6mm, with the width of under 500mm.
The regular specifications used in China are equal angle steel( the length of legs are 25-75mm), curb angle with involution( the length of legs are 40-75mm), U-steel(the height is 25-250mm), U-steel with involution(the height is 60-250mm), Z type steel (the height is 100-180 mm), which are more than 400 specifications and varieties. The products are widely used in many industries like mines, buildings, agricultural machinery, transportation, bridges, petrochemicals, light industry and electronics.
The cold forming selectional steel of Puri steel is the main material for making the lightweight steel structure, which is made with steel plate and cold forming selectional steel with steel band. The wall thickness of it can not only be made very thin but it can simplify the productive technology and enhance the productivity.
It can produce a variety of cold forming selectional steels that have uniform wall thickness and complicated shapes of sections and different materials ones. All that are difficult to realize when using hot rolling method. It is not only widely used in all kinds of building structure but cars manufacture and agricultural machinery. There are various cold forming selectional steel. Differing from their shapes of sections, there are open, semi-closed and closed. According to the shapes, there are cold-formed channel steel, angle steel, Z type steel, square pipe, rectangular tube, special-shaped tube, rolling curtain, etc. On the basis of the regulations of GB6725-92, the cold forming selectional steel is produced by common carbon structural steel, high-quality carbon structural steel, low alloy steel plate or steel strip made in cold bending.
The cold forming selectional steel belongs to economic section steel product and energy-efficient material, which is a new steel product owning strong vitality. And it is widely taken advantage of every field in national economy including 10 varieties such as road guardrails, steel structures, cars, containers, steel formwork and scaffolding, railway vehicles, ships and bridges, steel sheet piles, transmission towers and others.
At present, in the production of cold bending and hollow square rectangular steel, there are two kinds of different forming process. One is to be round first and then to be square or rectangular. Another is to be square or rectangular directly. For the time being, in the field of forming of square and rectangular steel tube, to be square and rectangular directly is the most advanced forming technology in international society. The technology to be square or rectangular straightly is more advanced than that of being round first and then being square or rectangular. The technology of being round first and then being square or rectangular will be harmful to steel band or material of plate rolling greatly while the one to be square and rectangular straight will not damage the materials, which can maintain the mechanical and physical properties, ensuring the high quality of product. It is known that a large steel pipe factory in Tai'an, Shandong, is using the direct square and rectangular forming technology, which has great molding effect.
In recent years, the needs of cold forming selectional steel market have been on the rise, and the range of applications for it has been enlarging constantly, which has a promising future. At present, it is urgent to develop stainless steel, galvanized sheet, cold forming selectional steel have high strength, ultra-high strength and low alloy, and a series of products with complex section that are super thick , ultra-thin.