Stainless steel pipes are divided into ordinary carbon steel pipes, high-quality carbon structural steel pipes, alloy structural pipes, alloy steel pipes, bearing steel pipes, stainless steel pipes and bimetal composite pipes, coatings and coated pipes to save precious metals and meet special requirements. There are many kinds of stainless steel pipes, because of different uses, their technical requirements are different, and the production methods are also different. The current production of steel pipe diameter range 0.1-4500mm, wall thickness range 0.01 ~ 250mm. In order to distinguish its characteristics, the steel pipe is usually classified according to the following method.

Mode of production

Stainless steel pipe according to the production method is divided into seamless pipe and welded pipe two categories. Seamless steel pipes can also be divided into hot-rolled pipes, cold-rolled pipes, cold-drawn pipes and extruded pipes. Cold drawing and cold rolling are the secondary processing of steel pipe. The welded pipe is divided into straight seam welded pipe and spiral welded pipe.

Section shape

Stainless steel pipe according to the cross-section shape can be divided into round pipe and shaped pipe. The special-shaped pipe has rectangular pipe, diamond pipe, oval pipe, hexagonal pipe, eight pipe and a variety of cross-section asymmetric pipe. Shaped tubes are widely used in various structural parts, tools and mechanical parts. Compared with the round tube, the shaped tube generally has a larger moment of inertia and section modulus, and has a larger bending and torsional resistance, which can greatly reduce the weight of the structure and save steel.

Pipe end shape

Stainless steel pipe can be divided into light pipe and wire pipe (with rebar steel pipe) according to the state of the pipe end. Wire pipe can also be divided into ordinary wire pipe (conveying water, gas and other low pressure pipe, using ordinary cylindrical or conical pipe thread connection) and special thread pipe (oil, geological drilling pipe, for important wire pipe, using special thread connection), for some special pipe, in order to make up for the impact of thread on the strength of the pipe end, Tube end thickening (internal thickening, external thickening or internal and external thickening) is usually carried out before wire drawing.

Use classification

According to the use can be divided into oil well pipe (casing, tubing and drill pipe, etc.), pipeline pipe, boiler pipe, mechanical structure pipe, hydraulic support pipe, gas cylinder pipe, geological pipe, chemical pipe (high-pressure fertilizer pipe, oil cracking pipe) and ship pipe.