Classification by steel pipe material:
Steel pipes can be divided into: carbon steel pipes, alloy steel pipes, stainless steel pipes, etc. Carbon pipes can be divided into ordinary carbon steel pipes and high-quality carbon structural pipes. Alloy tubes can be divided into: low alloy tubes, composite tubes, financial tubes, high-strength tubes, precision alloys (such as Kovar) tubes, and high-temperature alloy tubes.
Classification by connection method:
According to the connection method of the pipe end, the steel pipe can be divided into: bare pipe (the pipe end is not threaded) and the wire pipe (the pipe end is threaded).
The wire tube is further 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 threading pipe can also be divided into: ordinary cylindrical or conical thread and special threading and other threading pipes.
In addition, according to the needs of users, the wire tube is generally equipped with pipe joints for delivery.
Classification by coating characteristics:
According to the characteristics of surface coating, the steel pipe can be divided into: black pipe (uncoated) and coated pipe.
Coated pipes include galvanized pipes, aluminized pipes, chrome-plated pipes, aluminized pipes and other alloy-layered steel pipes.
Coated tubes include outer coating tubes, inner coating tubes, and inner and outer coating tubes. The commonly used coatings include plastics, epoxy resins, coal tar epoxy resins and various glass-type anti-corrosion coatings.
Galvanized pipe is further divided into: KBG pipe, JDG pipe, threaded pipe, etc.
Classified by section shape:
According to the cross-sectional shape, steel pipes can be divided into two types: round steel pipes and special-shaped pipes. Plum tube, etc.
Classification by use area:
1. Pipes for pipes. Such as: seamless pipes for water, gas pipes, steam pipes, oil pipelines, and pipes for oil and natural gas trunk lines. Agricultural irrigation faucets with pipes and sprinkler irrigation pipes, etc.
2. Tubes for thermal equipment. Such as boiling water pipes, superheated steam pipes for general boilers, superheating pipes, large smoke pipes, small smoke pipes, arch brick pipes and high temperature and high pressure boiler pipes for locomotive boilers.
3. Pipes for machinery industry. Such as aviation structural pipes (round pipes, elliptical pipes, flat elliptical pipes), automobile semi-axle pipes, axle pipes, automobile tractor structural pipes, tractor oil cooler pipes, agricultural machinery square pipes and rectangular pipes, transformer pipes and bearings. tube etc.
4. Pipes for petroleum geological drilling. Such as: oil drilling pipe, oil drill pipe (kelly and hexagonal drill pipe), drill pipe, oil tubing, oil casing and various pipe joints, geological drilling pipe (core pipe, casing, active drill pipe, drill pipe) , press hoop and pin joints, etc.).
5. Chemical industry pipes. Such as: oil cracking pipes, chemical equipment heat exchangers and pipes, stainless acid-resistant pipes, high-pressure pipes for chemical fertilizers, and pipes for transporting chemical media, etc.
6. Other departments use pipes. Such as: tubes for containers (tubes for high-pressure gas cylinders and tubes for general containers), tubes for instrumentation, tubes for watch cases, injection needles and tubes for medical devices, etc.
Steel pipes can also be classified according to the rolling process, whether there are seams or not. According to the classification of rolling process, steel pipes can be divided into hot-rolled steel pipes and cold-rolled steel pipes; according to whether the steel pipes have seams, steel pipes are divided into seamless steel pipes and welded steel pipes. Among them, commonly used welded steel pipes can be divided into high-frequency welded pipes according to the type of weld , straight seam submerged arc welded pipe, spiral submerged arc welded pipe, etc. 3 kinds.