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, as well as bimetallic composite pipes, coated and coated pipes to save precious metals and meet special requirements. There are various types and uses of stainless steel pipes, with varying technical requirements and production methods. The current production of steel pipes has an outer diameter range of 0.1-450mm and a wall thickness range of 0.01-250mm. To distinguish its characteristics, steel pipes are usually classified according to the following method.
Production method
Stainless steel pipes are divided into two categories according to production methods: seamless pipes and welded pipes. Seamless steel pipes can also 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 are divided into straight seam welded pipes and spiral welded pipes.
Section shape
Stainless steel pipes can be divided into circular and irregular pipes according to their cross-sectional shape. Special shaped pipes include rectangular pipes, diamond pipes, elliptical pipes, hexagonal pipes, octagonal pipes, and various asymmetric pipes with different cross-sections. Specially shaped pipes are widely used in various structural components, tools, and mechanical components. Compared with circular pipes, irregular pipes generally have larger moments of inertia and cross-sectional modulus, and have greater bending and torsion resistance, which can greatly reduce structural weight and save steel.
Stainless steel pipes can be divided into equal section pipes and variable section pipes according to their longitudinal shape. Variable cross-section pipes include conical pipes, stepped pipes, and periodic cross-section pipes.
Tube end shape
Stainless steel pipes can be divided into smooth pipes and threaded pipes (with threaded steel pipes) based on the state of the pipe ends. Car thread pipes can also be divided into ordinary car thread pipes (low-pressure pipes for conveying water, gas, etc., connected with ordinary cylindrical or conical pipe threads) and special thread pipes (pipes for petroleum and geological drilling, and important car thread pipes connected with special threads). For some special pipes, in order to compensate for the impact of threads on the strength of the pipe end, the pipe end is usually thickened (internal thickening, external thickening, or internal and external thickening) before the car thread.
Usage classification
According to their usage, they can be divided into oil well pipes (casing, oil pipes, drill pipes, etc.), pipeline pipes, boiler pipes, mechanical structure pipes, hydraulic support pipes, gas cylinder pipes, geological pipes, chemical pipes (high-pressure fertilizer pipes, petroleum cracking pipes), and ship pipes.