1. Classified by production method
(1) Seamless pipe -- hot rolled pipe, cold rolled pipe, cold drawn pipe, extrusion pipe, pipe jacking
(2) Welding pipe
(a)According to the process - arc welding pipe, resistance welding pipe (high frequency, low frequency), gas welding pipe, furnace welding pipe
(b) According to the weld, it can be divided into straight welded pipe and spiral welded pipe
2. Classification by section shape
(1) Simple section steel pipe -- round steel pipe, square steel pipe, oval steel pipe, triangular steel pipe, hexagonal steel pipe, diamond steel pipe, octagonal steel pipe, semicircular steel circle, other
(2) complex section steel pipe -- unequal hexagonal steel pipe, five valve plum shaped steel pipe, double convex steel pipe, double concave steel pipe, melon shaped steel pipe, conical steel pipe, corrugated steel pipe, watchcase steel pipe, other
3. According to the wall thickness classification - thin wall steel pipe, thick wall steel pipe
4. According to the use of the classification - pipe pipe, thermal equipment with steel pipe, mechanical industry with steel pipe, petroleum, geological drilling with steel pipe, container steel pipe, chemical industry with steel pipe, special purpose steel pipe, other
