Steel pipe is one of the four major categories of steel profiles, plates, pipes and metal products. It mainly began with the rise of the bicycle manufacturing industry, the development of oil in the early 19th century, the manufacture of ships, boilers and aircraft during the two World Wars, the manufacture of thermal power boilers after the Second World War, the development of the chemical industry and the drilling and transportation of oil and gas, etc., have strongly promoted the development of the steel pipe industry in varieties, output and quality.
Steel pipe classification:


According to the production method, it can be divided into two categories:seamless steel pipe and seam steel pipe, and seam steel pipe is referred to as straight seam steel pipe.

Seamless steel pipe according to the production method can be divided into:hot rolled seamless pipe, cold drawn pipe, precision steel pipe, hot expansion pipe, cold spinning pipe and extruded pipe. Seamless steel pipe is made of **** carbon steel or alloy steel, hot rolled, cold rolled (drawn) points.

Welded steel pipe is mainly welded steel pipe, because of its different welding process and divided into furnace welded pipe, electric welded pipe and automatic arc welded pipe, because of its different welding forms are divided into straight welded pipe and spiral welded pipe two kinds, because of its end shape is divided into circular welded pipe and shaped (square, flat, etc.) welded pipe.

According to the material can be divided into:carbon tube and alloy tube, stainless steel tube.

Carbon pipes can be divided into ordinary carbon steel pipes and **** carbon structure pipes.

Alloy pipe can be divided into:low alloy pipe, alloy structure pipe, high alloy pipe, high strength pipe. Bearing pipe, heat and acid resistant stainless pipe, precision alloy (such as Kovar alloy) pipe and high-temperature alloy pipe.

According to the connection method, it can be divided into light pipe (pipe end without thread) and wire pipe (pipe end with thread).

Turning wire pipe is divided into:ordinary turning wire pipe and pipe end thickened turning wire pipe.

According to the plating characteristics can be divided into:black tube (not coated) and coated tube.

The coated pipe has galvanized pipe, aluminized pipe, chromium-plated pipe, aluminized pipe and other alloy layer steel pipe.

The coated tube has an outer coated tube, an inner coated tube and an inner and outer coated tube. Commonly used coatings are plastic, epoxy resin, coal tar epoxy resin and various glass type anticorrosive coatings. Galvanized pipe is divided into KBG pipe, JDG pipe, threaded pipe and so on

Classification by use

Pipes for pipes. Such as:seamless pipe for water, gas pipe, steam pipe, oil transmission pipe, oil and natural gas trunk pipe. Agricultural irrigation water faucet with pipe and sprinkler irrigation pipe.

Pipes for thermal equipment. Such as boiling water pipe, superheated steam pipe for general boilers, superheating pipe for locomotive boilers, large smoke pipe, small smoke pipe, arch brick pipe and high temperature and high pressure boiler pipe.

Pipe for mechanical industry. Such as aviation structure tube (round tube, oval tube, flat oval tube), automobile axle tube, axle tube, automobile tractor structure tube, tractor oil cooler tube, agricultural machinery square tube and rectangular tube, transformer tube and bearing tube.

Pipe for petroleum geological drilling. Such as:oil drilling pipe, oil drill pipe (kelly pipe and hexagonal drill pipe), drilling stick, oil tubing, oil casing and various pipe joints, geological drilling pipe (core pipe, casing, active drill pipe, drill stick, press hoop and pin joint, etc.).

Tubes for the chemical industry. Such as:petroleum cracking pipe, chemical equipment heat exchanger and pipeline pipe, stainless acid resistant pipe, high pressure pipe for fertilizer and pipe for conveying chemical media.

Other departments use tubes. Such as:container tube (high-pressure gas cylinder tube and general container tube), instrument tube, watch case tube, syringe needle and medical equipment tube.

According to the section shape can be divided into:round steel pipe and shaped steel pipe.



Shaped steel pipe refers to a variety of non-circular circular section of steel pipe. The main ones are:square tube, rectangular tube, elliptic tube, flat elliptic tube, semicircular tube, hexagonal tube, hexagonal inner tube, unequal hexagonal tube, equilateral triangle tube and so on