Galvanized square tube & rectangular tube
1. The allowable deviation of the wall thickness of the galvanized rectangular tube shall not exceed plus or minus 10% of the nominal wall thickness when the wall thickness is less than 10mm, and when the wall thickness is greater than 10mm, it is plus or minus 8% of the wall thickness. Except for the wall thickness in the seam area.
2. The usual delivery length of galvanized rectangular tube is 4000mm-12000mm, mostly 6000mm and 12000mm. Rectangular pipes are allowed to deliver short-length and non-fixed-length products not less than 2000mm, and can also be delivered in the form of interface pipes, but the buyer should cut off the interface pipe when using it. The weight of short-length and non-fixed-length products should not exceed 5% of the total delivery volume, and for square rectangular tubes with a theoretical weight greater than 20kg/m, it should not exceed 10% of the total delivery volume.
3. The curvature of the galvanized rectangular tube shall not be greater than 2mm per meter, and the total curvature shall not be greater than 0.2% of the total length.
1. Production process classification of rectangular tube
Rectangular tubes are classified according to the production process: hot-rolled seamless square tubes, cold-drawn seamless square tubes, extruded seamless square tubes, and welded square tubes. Among them, the welded square pipe is divided into: (a) According to the process-arc welding square pipe, resistance welding square pipe (high frequency, low frequency), gas welding square pipe, furnace welding square pipe (b) according to the weld-straight Seam welded square pipe, spiral welded square pipe
2. Material classification of rectangular tube
Square pipes are classified according to their materials: plain carbon steel square pipes and low-alloy square pipes. Common 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, etc.
3. Standard classification of rectangular tube production
Square pipes are classified according to production standards: national standard square pipes, Japanese standard square pipes, imperial square pipes, American standard square pipes, European standard square pipes, and non-standard square pipes.
4. The shape classification of the rectangular tube section
Square pipes are classified according to their cross-sectional shapes: (1) simple cross-section square pipes-square square pipes, rectangular square pipes (2) complex cross-section square pipes-flower-shaped square pipes, open-shaped square pipes, corrugated square pipes, special-shaped square pipes
5. Surface treatment classification of rectangular tube
Square pipes are divided into surface treatments: hot-dip galvanized square pipes, electro-galvanized square pipes, oil-coated square pipes, pickled square pipes
6. Use classification of rectangular tube
Square pipes are classified by purpose-square pipes for decoration, square pipes for machine tools, square pipes for machinery industry, square pipes for chemical industry, square pipes for steel structures, square pipes for shipbuilding, square pipes for automobiles, square pipes for steel beams and columns Tube, special purpose square tube
7. Classification of rectangular tube wall thickness
Rectangular pipes are classified by wall thickness-super thick-walled rectangular pipes, thick-walled rectangular pipes and thin-walled rectangular pipes
Mainly used in curtain walls, construction, machinery manufacturing, steel construction projects, shipbuilding, solar power generation brackets, steel structure engineering, power engineering, power plants, agricultural and chemical machinery, glass curtain walls, automobile chassis, airports, etc.
Theoretical weight of galvanized square pipe per meter
4*Side length*0.00785*1.06*Thickness 4*Side length*0.00785*Thickness