Seamless square steel pipe
Seamless square steel pipe according to the production process: hot-rolled seamless square tube, cold drawn seamless square tube, extruded seamless square tube, welded square tube.
2. Among them, the welded square tube is further divided into: (a) according to the process points - arc welded square tube, resistance welded square tube (high frequency, low frequency), gas welded square tube, furnace welded square tube; (b) according to the weld ——Stitched square tube and spiral welded square tube.
3. Material classification
Seamless square steel pipe according to material: ordinary carbon steel square tube, low alloy square tube. The carbon steel
is divided into: Q195, Q215, Q235, SS400, 20# steel, 45# steel, etc.; low alloy steel is divided into Q345, 16Mn, Q390, ST52-3 and so on.
4. Production standard classification
Seamless square steel pipe according to production standards: national standard square tube, Japanese standard square tube, inch square tube, American standard square tube, European standard square tube, non-standard square tube.
5. Section shape classification
Square tubes are classified according to the shape of the section: (1) square tube with simple section - square square tube, rectangular square tube
; (2) square tube with complex section - flower square tube, open square tube, corrugated square tube, shaped square tube.
6. Surface treatment classification
Seamless square steel pipe according to surface treatment: hot-dip galvanized square tube, electro-galvanized square tube, oil-coated square tube, pickled square tube.
7. Use classification
Seamless square steel pipe according to the purpose - decorative square tube, square tube for machine tool equipment, square tube for machinery industry, square tube for chemical industry, square tube for steel structure, square tube for shipbuilding, square tube for automobile, steel beam column Square tube, special purpose square tube.
8. Wall thickness classification
Square tubes are classified according to wall thickness - ultra thick wall square tubes, thick wall square tubes and thin wall square tubes.
9. In addition, square tube performance plasticity
Plasticity refers to the ability of a metal material to undergo plastic deformation (permanent deformation) without damage under load.