1. by production method

Steel pipes can be divided into two categories according to production methods: seamless steel pipes and welded steel pipes

1. Seamless steel pipes are made of carbon steel or alloy steel, and are hot-rolled and cold-rolled (drawn). Seamless steel pipes can be used for liquid pressure pipes and gas pipes in various industries.

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.

2. Welded steel pipe is made of rolled into a tube-shaped steel plate to seam or spiral seam welding. Our common water pipes, gas pipes, heating pipes, electrical pipes, etc. are welded steel pipes.

According to the welding process, it is divided into furnace welded pipe, electric welding (resistance welding) pipe and automatic arc welded pipe.

According to the welding form is divided into: straight seam welded pipe and spiral welded pipe two kinds.

According to the end shape, it is divided into round welded pipe and special-shaped (square, flat, etc.) welded pipe.

According to the manufacturing method, it is divided into low-pressure fluid conveying welded steel pipe, spiral seam welded steel pipe, direct coil welded steel pipe, electric welded pipe, etc.

2. classified by connection method

The steel pipe can be divided into: smooth pipe (pipe end without thread) and turning wire pipe (pipe end with thread).

Turning wire tube is divided into: ordinary turning wire tube and tube end thickening turning wire tube. Thickened turning pipe can also be divided into: external thickening (with external thread), internal thickening (with internal thread) and internal and external thickening (with internal and external thread) and other local turning pipe.

According to the thread type, the thread turning tube can also be divided into: ordinary cylindrical or conical thread and special thread turning tube.

3. by Purpose

1. Pipeline steel pipe: such as: water, gas pipe, steam pipe with seamless pipe, oil pipeline, oil and gas trunk pipe. Agricultural irrigation tap with pipe and sprinkler irrigation pipe, etc.

2. Steel pipes for thermal equipment: such as boiling water pipes and superheated steam pipes for general boilers, superheat pipes, large smoke pipes, small smoke pipes, arch brick pipes and high temperature and high pressure boiler pipes for locomotive boilers.

3. Steel pipes for machinery industry: such as aviation structural pipes (round pipes, elliptical pipes, flat elliptical pipes), automobile half-shaft pipes, axle pipes, automobile tractor structural pipes, tractor oil cooler pipes, agricultural machinery square pipes and rectangular pipes, transformer pipes and bearing pipes.

4. Steel pipes for petroleum geological drilling: such as: petroleum drilling pipes, petroleum drill pipes (kelly and hexagonal drill pipes), drilling sticks, petroleum oil pipes, petroleum casings and various pipe joints, geological drilling pipes (core pipes, casings, active drill pipes, drilling sticks, press hoops and pin joints, etc.).

5. Steel pipes for chemical industry: such as petroleum cracking pipes, heat exchangers and pipelines for chemical equipment, stainless acid-resistant pipes, high-pressure pipes for chemical fertilizers, and pipes for conveying chemical media.

6. Steel pipes for other departments: such as: container pipes (high-pressure gas cylinder pipes and general container pipes), instrument pipes, watch case pipes, injection needles and medical equipment pipes, etc.

4. by section shape

Steel pipes can be divided into round steel pipes and special-shaped steel pipes according to their cross-sectional shapes.