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Classification of rectangular tubes

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Rectangular tube, also known as square and rectangular cold-formed hollow section steel, is a kind of address for square pipe and rectangular pipe, that is, steel pipe with equal or unequal side length, code named F and j respectively. It is made of strip steel after process treatment. Generally, the strip steel is unwrapped, flattened, crimped and welded to form a round tube, which is then rolled into a square tube and then cut into the required length.

I. process classification:

According to the production process, square rectangular tube is divided into hot rolled seamless square tube, cold drawn seamless square tube, extruded seamless square tube and welded square tube. The welded square tube is divided into: 1. According to the process, it is divided into arc welding square pipe, resistance welding square pipe (high frequency and low frequency), gas welding square pipe and furnace welding square pipe. 2. According to the welding seam, it is divided into longitudinal welding square pipe and spiral welding square pipe.

2、 Material classification

According to the material, the square pipe is divided into ordinary carbon steel square pipe and low alloy square pipe. 1. Ordinary carbon steel is divided into: Q195, Q215, Q235, SS400, 20 ᦇ steel, 45 ᦇ steel, etc. 2. Low alloy steels are divided into Q345, 16Mn, Q390, St52-3, etc. 3、 Classification of production standards:

Square tube according to the production standards: national standard square tube, Japanese standard square tube, English square tube, American standard square tube, European standard square tube, non-standard square tube. 4、 Classification of section shape:

Square tubes are classified according to section shape: 1. Simple section square tubes: square square tubes and rectangular square tubes. 2. Complex cross-section square pipe: flower shaped square pipe, open-ended square pipe, corrugated square pipe, special-shaped square pipe.

V. classification of surface treatment:

According to the surface treatment, square pipes are divided into hot-dip galvanized square pipes, electro galvanized square pipes, oil coated square pipes and acid pickling square pipes. 6、 Usage classification:

Square tubes are classified according to their uses: square tubes for decoration, square tubes for machine tools, square tubes for mechanical industry, square tubes for chemical industry, square tubes for steel structures, square tubes for shipbuilding, square tubes for automobiles, square tubes for steel beams and columns, and square tubes for special purposes. 7、 Wall thickness classification: rectangular tubes are classified according to wall thickness: ultra thick rectangular tubes, thick rectangular tubes and thin-walled rectangular tubes.

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