Welded steel pipes are divided into furnace welded pipes, electric resistance welded (resistance welded) pipes and automatic arc welded pipes due to their different welding processes. Due to their different welding methods, they are divided into two types: straight seam welded pipes and spiral welded pipes. They are divided into two types because of their end shapes. It is round welded pipe and special-shaped (square, flat, etc.) welded pipe.
Welded steel pipes are formed by welding steel plates rolled into a tube shape with butt or spiral seams. In terms of manufacturing methods, they are divided into welded steel pipes for low-pressure fluid transportation, spiral seam electric welded steel pipes, direct coil welded steel pipes, and electric welded pipes. Seamless steel pipes can be used for liquid pneumatic pipelines and gas pipelines in various industries. Welded pipelines can be used for water pipelines, gas pipelines, heating pipelines, electrical pipelines, etc.
Folded by material
Steel pipes can be divided into carbon pipes, alloy pipes, stainless steel pipes, etc. according to the pipe material (that is, steel type).
Carbon tubes can be divided into ordinary carbon steel tubes and high-quality carbon structural tubes.
Alloy tubes can be divided into: low alloy tubes, alloy structural tubes, high alloy tubes, and high strength tubes. Bearing tubes, heat-resistant and acid-resistant stainless tubes, precision alloy (such as Kovar) tubes and high-temperature alloy tubes, etc.
Folding is classified by connection method
Steel pipes can be divided into smooth pipes (with no threads on the pipe ends) and threaded pipes (with threads on the pipe ends) according to the connection method of the pipe ends.
The wire tube is divided into: ordinary wire tube and tube end thickened wire tube.
Thickened wire tubes can also be divided into: external thickening (with external threads), internal thickening (with internal threads), and internal and external thickening (with internal and external threads).
According to the thread type, the threaded tube can also be divided into: ordinary cylindrical or conical thread and special thread and other threaded tubes.
In addition, according to user needs, wire pipes are generally delivered with pipe joints.
Folding and coating features
Steel pipes can be divided into black pipes (not plated) and coated pipes according to the characteristics of surface coating.
Coated pipes include galvanized pipes, aluminized pipes, chrome-plated pipes, aluminized pipes and other alloy-coated steel pipes.
Coated pipes include outer-coated pipes, inner-coated pipes, and inner-outer coated pipes. The commonly used coatings are plastic, epoxy resin, coal tar epoxy resin and various glass-type anticorrosive coating materials. Galvanized pipes are divided into KBG pipes, JDG pipes, threaded pipes, etc.
Folded by purpose
1. Pipes for pipes. Such as: seamless pipes for water, gas pipes, steam pipes, oil transportation pipes, and oil and gas trunk lines. Agricultural irrigation water taps with pipes and sprinkler irrigation pipes, etc.
2. Thermal equipment pipes. Such as boiling water pipes and superheated steam pipes for general boilers, superheating pipes, large smoke pipes, small smoke pipes, arched brick pipes and high temperature and high pressure boiler pipes for locomotive boilers.
3. Pipes for machinery industry. Such as aviation structural tubes (round tubes, oval tubes, flat oval tubes), automotive half-shaft tubes, axle tubes, automotive tractor structural tubes, tractor oil cooler tubes, agricultural machinery square tubes and rectangular tubes, transformer tubes, and bearings Tube and so on.
4. Pipes for petroleum geological drilling. Such as: oil drilling pipes, oil drill pipes (kelly and hexagonal drill pipes), drill pipes, oil tubing, oil casing and various pipe joints, geological drilling pipes (core pipes, casings, active drill pipes, drill pipes) , Press hoop and pin joints, etc.).
5. Tubes for the chemical industry. Such as: petroleum cracking pipes, chemical equipment heat exchangers and pipes, stainless acid-resistant pipes, high-pressure pipes for fertilizers, and pipes for transporting chemical media.
6. Other departments use management. Such as: container tubes (tubes for high-pressure gas cylinders and general container tubes), tubes for instruments and instruments, tubes for watch cases, injection needles and tubes for medical devices, etc.