Classified by production methods
(1) Seamless steel pipes-hot rolled pipes, cold rolled pipes, cold drawn pipes, extruded pipes, pipe jacking
(2) Welded steel pipe
Classified by pipe material-carbon steel pipe and alloy pipe
Carbon steel pipes can be further divided into: ordinary carbon steel pipes and high-quality carbon steel structural pipes
Alloy pipes can be further divided into: low alloy pipes, alloy structural pipes, high alloy pipes, heat-resistant and acid-resistant stainless pipes, high-temperature alloy pipes, etc.
Classified by section shape-round and special-shaped
Classification by wall thickness-thin-walled steel pipe, thick-walled steel pipe
Classified by purpose-steel pipes for pipelines, steel pipes for thermal equipment, steel pipes for machinery industry, steel pipes for petroleum, geological drilling, steel pipes for container, steel pipes for chemical industry, steel pipes for special purposes, steel pipes for other purposes.
Seamless steel pipes are made of steel ingots or solid tube billets through perforation into rough tubes, and then made by hot rolling, cold rolling or cold drawing.
The specification of seamless steel pipe is generally expressed by the nominal size of the outer diameter and wall thickness of the finished steel pipe (mm)
Because of their different manufacturing processes, they are divided into two types: hot-rolled (extruded) seamless steel pipes and cold-drawn (rolled) seamless steel pipes.
Hot-rolled seamless steel pipes are divided into general steel pipes, low and medium pressure boiler steel pipes, high pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, geological steel pipes and other steel pipes.
Cold-rolled (dial) seamless steel pipes are divided into general steel pipes, low and medium pressure boiler steel pipes, high pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, and other steel pipes, as well as carbon thin-walled steel pipes, alloy thin-walled steel pipes, Stainless thin-walled steel pipes, special-shaped steel pipes.