Classification
By production method
Steel pipes can be divided into two categories according to the production methods: seamless steel pipes and seamed steel pipes, and seamed steel pipes are referred to as straight seam steel pipes.
1. Seamless steel pipes can be classified according to production methods: hot-rolled seamless pipes, cold-drawn pipes, precision steel pipes, heat-expanded pipes, cold spinning pipes and extruded pipes.
Seamless steel tubes are made of high-quality carbon steel or alloy steel, with hot rolling, cold rolling (pulling).
Bundle of steel pipes
Bundle of steel pipes
2. Welded steel pipes are divided into furnaces, electric welding (resistance welding) pipes and automatic arc welding pipes because of their different welding processes. Because of their different welding modes, they are divided into two types: straight seam welded pipe and spiral welded pipe. For the round pipe and shaped (square, flat, etc.) welded pipe.
Welded steel tubes are made by rolling into a tube-shaped steel plate and welded to a seam or spiral seam. In terms of manufacturing methods, they are divided into welded steel pipes for low-pressure fluid transportation, spiral welded steel pipes, direct welded steel tubes, and welded pipes. Seamless steel tubes can be used in various industries such as liquid pressure piping and gas piping. Welded pipes can be used for water pipes, gas pipes, heating pipes, electrical pipes, etc.
By material
According to the pipe material (steel), the steel pipe can be divided into: carbon pipe and alloy pipe, stainless steel pipe and so on.
Carbon tubes can be divided into ordinary carbon steel tubes and high-quality carbon structural tubes.
Alloy tube can be divided into: low alloy tube, alloy structure tube, high alloy tube, high strength tube. Bearing tube, heat-resistant acid-resistant stainless tube, precision alloy (such as Kovar) tube, and high-temperature alloy tube.
Classified by connection method
According to the pipe end connection, the steel pipe can be divided into: light pipe (without pipe end) and wire pipe (with pipe end with thread).
The wire tube is divided into: ordinary wire tube and pipe end thickened wire tube.
Thickened wire tube can also be divided into: external thickening (with external thread), internal thickening (with internal thread) and internal and external thickening (with internal and external threads) and other ground wire tube.
If the wire tube type according to the thread type can also be divided into: ordinary cylindrical or conical thread and special thread and other wire tube.
In addition, according to the needs of users, the wire tube is generally equipped with a pipe joint delivery.
Press coating features
According to the surface coating characteristics of steel pipes can be divided into: black (not coated) and coated pipe.
The coating tubes include galvanized tubes, aluminized tubes, chrome-plated tubes, aluminized tubes, and other alloyed steel tubes.
Coating tubes include outer coating tubes, inner coating tubes, and inner and outer coating tubes. Commonly used coatings are plastics, epoxy resins, coal tar epoxy resins, and various types of glass anti-corrosion coating materials. Galvanized pipe is divided into KBG pipe, JDG pipe, threaded pipe, etc.
By use
1. Pipeline pipe. Such as: water, gas pipe, steam pipe with seamless pipe, oil pipe, oil and gas trunk pipe. Agricultural irrigation taps with pipes and irrigation sprinklers.
2. Tubes for thermal equipment. Such as general boiler boiling water pipe, superheated steam pipe, locomotive boiler superheated pipe, smoke pipe, small smoke pipe, arched brick pipe and high temperature and high pressure boiler pipe.
3. The tube for machinery industry. Such as aeronautical structural tubes (circular tubes, elliptical tubes, flat oval tubes), automotive axle tubes, axle tubes, automobile tractor structural tubes, oil cooler tubes for tractors, square tube and rectangular tubes for agricultural machinery, tubes for transformers, and bearings Tubes and so on.
4. Petroleum geological drilling pipe. Such as: oil drilling pipe, oil drill pipe (for kelly and hexagonal drill pipe), drill collar, petroleum tubing, oil casing and various pipe joints, geological drilling pipe (core pipe, casing, active drill pipe, drill collar , hoop and pin joints, etc.).
5. Pipes for the chemical industry. Such as: oil cracking pipe, chemical equipment, heat exchangers and pipelines, stainless acid, high-pressure chemical fertilizers, and transportation of chemical media.
6. Other departments use the tube. Such as: container tube (high-pressure gas cylinder tube and general container tube), instrumentation equipment, watch shell tube, injection needle and its medical device tubes. [2]
By section shape
The steel grades and specifications of steel pipe products are extremely varied, and their performance requirements are also varied. All of these should be differentiated as user requirements or working conditions change. In general, steel pipe products are classified according to the cross-sectional shape, production method, pipe material, connection method, plating characteristics, and use.
According to the cross-sectional shape of the steel pipe can be divided into: round steel pipe and shaped steel pipe.
Special-shaped steel pipe refers to all kinds of non-circular-shaped steel pipe. Among them are: square tube, rectangular tube, oval tube, flat elliptical tube, semicircular tube, hexagonal tube, hexagonal inner tube, unequal hexagonal tube, equilateral triangle tube, pentagonal plum tube, octagonal tube, convex Font tube, double convex tube. Bi-concave tube, multi-concave tube, melon tube, flat tube, diamond tube, star tube, parallelogram tube, ribbed tube, drop tube, inner fin tube, twisted tube, B-tube, D Type tubes and multilayer tubes.
According to the longitudinal section of the steel pipe is divided into: equal section steel pipe and variable section steel pipe. Variable section (or variable section) steel tube refers to a steel tube that undergoes periodic or aperiodic changes along the length of the tube in the cross-sectional shape, inner and outer diameters, and wall thicknesses. The main ones are: outer conical tube, inner conical tube, outer step tube, inner step tube, periodic cross-section tube, corrugated tube, spiral tube, steel tube with radiating fins, and barrel with double wire.
