Classification of stainless steel pipes

Classification of stainless steel pipes

Stainless steel pipe is a common steel material, more different standards and uses, can be divided into a variety of types.

Classified by manufacturing process

1. Seamless stainless steel pipe
Seamless stainless steel pipes are produced by hot rolling, cold rolling or cold drawing processes. The whole steel pipe has no weld, and the structure is uniform.
2. Weld stainless steel pipes
It is welded by stainless steel plate or steel coil and has obvious welding seam. The welded stainless steel pipe can also be classified as straight seam welded pipe and spiral welded pipe. The weld of the straight seam welded steel pipe is a straight line, which is suitable for low-pressure liquid transportation. The weld of spiral welded steel pipe is spiral, which is suitable for long-distance transportation.

Classification by material:

Austenitic stainless steel pipe:
Main composition: Chromium (Cr) ≥ 18%, nickel (Ni) ≥ 8%, containing a small amount of molybdenum (Mo), titanium (Ti) and other elements.
Features: Excellent corrosion resistance, good toughness, suitable for a variety of complex environments.

Ferritic stainless steel pipe:
Main ingredients: high chromium content (12%-30%), low nickel content or no nickel.
Features: pitting resistance, oxidation resistance is strong, but the welding performance is poor.

Martensitic stainless steel pipe
Main ingredients: Chromium content is 12%-18%, high carbon content.

Duplex stainless steel pipe
Main components: austenite and ferrite two-phase structure, moderate chromium and nickel content, high molybdenum content.
Features: High strength, excellent corrosion resistance, especially suitable for chloride-containing environment.

Precipitation hardened stainless steel tube
Features: Strength and hardness can be significantly improved by heat treatment, medium corrosion resistance.

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

Classification by raw materials
It is divided into general carbon steel pipe, high-quality carbon structure steel pipe, alloy structure pipe, alloy steel pipe, bearing steel pipe, stainless steel pipe and bimetal composite pipe, coated pipe and coated pipe used to save precious metals and meet special requirements.