Welded Square Tube
made in China
Application: boiler tube,
Whether the pipeline is connected with alloy: non-alloy
Sectional shape: square
Special tube: API
Tube thickness: 1.5-60
Surface treatment: black paint
Tolerance: ±1%
Processing services: bending, welding, punching, cutting
Material: Q195/Q215/Q235/Q345/10#/20#
Surface: black spray paint
Shape: square tube
Packing: standard packing
Keywords: seamless steel pipe
Delivery time: 7-15 days
Inner shape steel pipe: black hollow section
Minimum order quantity: 1 ton
Purpose: Building structure
Technology: Hot Rolling
Authentication: API
1. Welded square tube is a hollow square section steel square tube, also known as hollow cold-formed steel. It is formed by cold bending and high-frequency welding after hot-rolled or cold-rolled strip or coil as the blank Shaped steel with square cross-sectional shape and size.
In addition to the thickening of the wall thickness of the thick-walled square tube, the corner size and edge flatness reach or exceed the level of the resistance welded cold-formed square tube. The size of the R angle is generally between 2 times and 3 times the wall thickness. .According to the needs of customers, we can also produce R-angle square tubes of the size required by customers;
2. Square tube Seamless square tube is a long steel strip with a hollow section and no joints on the periphery. It is a square tube formed by extruding a seamless tube through 4 sides of a mold. The square tube has a hollow section and is used in large quantities. It is used in liquid transportation, hydraulic support, mechanical structure, medium and low pressure, high pressure boiler tube, heat exchange tube, gas, petroleum and other industries. It is stronger than welded and will not crack.
1. Process flow of sanitary mirror tube:
Tube blank-inspection-peeling-inspection-heating-perforation-pickling-grinding-lubrication and air drying-welding head-cold drawing-solution treatment-pickling-pickling Passivation-inspection-cold rolling-degreasing-cutting-air drying-internal polishing-external polishing-inspection-marking-finished product packaging.
2. Industrial pipe process
Tube blank-inspection-peeling-inspection-heating-perforation-pickling-grinding-lubrication and air drying-welding head-cold drawing-solution treatment-pickling-pickling Passivation-inspection.
3. Process flow of welded pipe
Uncoiling-leveling-end shearing and welding-looper-forming-welding-inner and outer bead removal-pre-correction-induction heat treatment-sizing and straightening-eddy current testing-cutting ——Hydraulic pressure inspection——Pickling——Final inspection——Packing.
4. Seamless square tube process
Round steel-tube billet-inspection-heating-piercing-sizing-hot rolling-flat head-inspection-pickling-spherical annealing-cold drawing-forming-Qikou- -test
Q345A：C≤0.20，Mn ≤1.70，Si≤0.50，P≤0.035，S≤0.035；
Q345B：C≤0.20，Mn ≤1.70，Si≤0.50，P≤0.035，S≤0.035；
Q345C：C≤0.20，Mn ≤1.70，Si≤0.50，P≤0.030，S≤0.030，Al≥0.015；
Q345D：C≤0.18，Mn ≤1.70，Si≤0.50，P≤0.030，S≤0.025，Al≥0.015；
Q345E：C≤0.18，Mn ≤1.70，Si≤0.50，P≤0.025，S≤0.020，Al≥0.015；
Q345A, B, C, D, E Nb≤0.07，V≤0.15，Ti≤0.20，Cr≤0.30，N≤0.012，Mo≤0.10. 20#, Q235B
| Thick-walled square pipe specification table (mm) | Thick-walled rectangular pipe specification table (mm) | ||
| 16~34×0.4～2.0 | 380~500×380~500×8.0～30.0 | 10~20×20~40×0.6～12.0 | 250~300×100~250×6～30.0 |
| 16~34×0.4～2.0 | Another redraw specification is as follows | 20×50×1.0～2.0 | 400×250×8～30.0 |
| 38×38×1.0～4.0 | 550×550×10.0～40.0 | 22~40×35~100×0.9～5.0 | 400~×300×8～30.0 |
| 40~95×40~95×1.0～8.0 | 600~1000×600~1000×10.0～50.0 | 25×40×0.9～3.75 | 450~500×200~450×8～30.0 |
| 100×100×2.0～8.0 | 50×60×2.0～5.0 | Another redraw specification is as follows | |
| 120~350×120~350×4.0～30.0 | 50~200×60~150×2.0～12.0 | 600~1000×200~800×10～28.0 | |
