Various classification methods of stainless steel pipes

In the category of stainless steel materials, as long as it is open at both ends and has a hollow section, and the ratio of its length to the circumference of the section is relatively large, it can be called a stainless steel pipe. If the ratio of length to section circumference is relatively small, it can be called a pipe segment or a pipe fitting, but they all belong to the scope of pipes.

There are many types of stainless steel pipes, with different uses and technical requirements, and the production and processing techniques are also different. In order to make a distinction, various stainless steel pipes are generally classified according to the following methods.

According to the production method, stainless steel pipes are divided into two types: seamless pipes and welded pipes. Seamless steel pipes can be divided into hot-rolled pipes, cold-rolled pipes, cold-drawn pipes and extruded pipes. Cold-drawn and cold-rolled pipes are secondary processing of steel pipes. . Welded pipes can be divided into straight seam welded pipes and spiral welded pipes.

According to the cross-sectional shape, stainless steel pipes can be divided into round pipes and special-shaped pipes. Special-shaped tubes include rectangular tubes, rhombus tubes, oval tubes, hexagonal tubes, octagonal tubes and various asymmetrical cross-section tubes. Special-shaped tubes are widely used in various structural parts, tools and mechanical parts. Compared with round pipes, special-shaped pipes generally have a larger moment of inertia and section modulus, and have greater bending and torsion resistance, which can greatly reduce the structural weight and save steel. In addition, according to the shape of the longitudinal section, it can be divided into equal-section pipes and variable-section pipes. Variable-section pipes include tapered pipes, stepped pipes, periodic section pipes, etc.

According to material, stainless steel pipes can be 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 bimetallic composite pipes, plating and coatings to save precious metals and meet special requirements. Guan et al.

According to the purpose, stainless steel pipes can be divided into oil well pipes, pipeline pipes, boiler pipes, mechanical structural pipes, hydraulic support pipes, gas cylinder pipes, geological pipes, chemical pipes (high-pressure fertilizer pipes, petroleum cracking pipes) and ship pipes.

Finally, according to the shape of the pipe end, stainless steel pipes can be divided into plain pipes and wire pipes. Threaded pipes can also be divided into ordinary threaded pipes and special threaded pipes. For some special-purpose pipes, in order to compensate for the adverse impact of threads on the strength of the pipe end, the pipe end is generally thickened before threading.