Stainless steel pipe can be divided into ordinary carbon steel pipe, high quality carbon steel pipe, alloy structure pipe, alloy steel pipe, bearing steel pipe, stainless steel pipe and bimetal composite pipe, coating and coating pipe to save precious metals and meet special requirements. Stainless steel pipes have many kinds and different uses, different technical requirements and different production methods. At present, the outer diameter and wall thickness of steel pipes are 0.1-4500 mm and 0.01-250 mm respectively. In order to distinguish its characteristics, steel pipes are usually classified according to the following methods.

 

Mode of production

 

Stainless steel pipes can be divided into seamless pipes and welded pipes according to the mode of production. 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 the secondary processing of steel pipes. Welded pipes can be divided into straight-welded pipes and spiral-welded pipes.

 

Section shape

 

Stainless steel pipes can be divided into round pipes and special-shaped pipes according to their cross-sectional shapes. There are rectangular, rhombic, elliptical, hexagonal, octagonal and various cross-section asymmetrical tubes. Profiled tubes are widely used in various structural parts, tools and mechanical parts. Compared with circular tubes, special-shaped tubes generally have larger inertia moment and section modulus, and have greater flexural and torsional resistance, which can greatly reduce the weight of the structure 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 pipe has conical pipe, ladder pipe and periodic cross-section pipe, etc.

 

Tube End Shape

 

Stainless steel pipe can be divided into smooth pipe and threaded pipe according to the state of pipe end. The threaded pipe can be divided into ordinary threaded pipe (conveying water, gas and other low-pressure pipes, using threaded connection of ordinary cylinder or conical pipe) and special threaded pipe (petroleum, geological drilling pipe, for important threaded pipe, using special threaded connection), and some special threaded pipes. In order to compensate for the influence of threads on the strength of the end of the pipe, the end of the pipe is usually thickened before the threaded pipe (internal thickening, geological drilling pipe). External or internal thickening.

 

Classification of uses

 

It can be divided into oil well pipes (casing, tubing and drill pipe, etc.), pipelines, boiler pipes, mechanical structure pipes, hydraulic prop pipes, cylinder pipes, geological pipes, chemical pipes (high pressure fertilizer pipes, petroleum cracking pipes) and marine pipes.

 

production

 

Stainless steel welded pipe production process:

 

Raw materials - strip - welding pipe - repair end - polishing - Inspection (spray printing) - Packaging - delivery (warehousing) (decorative welded pipe).

 

Raw materials - slicing - welded pipe - heat treatment - straightening - Repair - Pickling - Hydrostatic testing - Inspection (spray printing) - Packaging - delivery (warehousing) (pipe for pipe distribution in welded pipe industry).