Galvanized square pipe, also known as square pipe or rectangular pipe, is a kind of steel pipe with equal length and is widely used in industry. Galvanized rectangular pipe is made of strip steel through a special process. Strip steel is generally unpacked, flattened, curled, welded into a round tube, and then rolled into a square tube from the round tube. At this time, the galvanized rectangular tube is made. Each package contains 50 galvanized square rectangular tubes, sometimes referred to as square rectangular tubes. Next, the specifications and classification of galvanized square rectangular tubes are introduced.

Specification of galvanized square pipe:

1, the allowable deviation of the wall thickness of galvanized square pipe shall not exceed+10% of the nominal wall thickness when the wall thickness is not greater than 10mm, and 8% of the wall thickness when the wall thickness is greater than 10mm, except for the wall thickness of corner and weld zone.

2. The delivery length of galvanized square rectangular pipes is usually 4000mm- 12000mm, mostly 6000mm and 12000mm. Square rectangular pipes are allowed to transport short-length and non-fixed-length products not less than 2000mm, and they can also be transported in the form of interface pipes, but the buyer should cut off the interface pipes when using them. The weight of short-length and non-fixed-length products shall not exceed 5% of the total delivery, and the square rectangular pipe with theoretical weight greater than 20kg/m shall not exceed 10% of the total delivery.

3. The bending degree of galvanized square pipe is not more than 2mm per meter, and the total bending degree is not more than 0.2% of the total length.

Classification of galvanized square pipes:

1. Square rectangular tubes are divided into hot-rolled seamless square tubes, cold-drawn seamless square tubes, extruded seamless square tubes and welded square tubes according to the production process. Among them, the welded square tube is divided into: (a) arc welding square tube, resistance welding square tube (high frequency and low frequency), gas welding square tube and furnace welding square tube; (b) Straight welded square pipes and spiral welded square pipes are arranged according to the weld.

2. Material classification of square pipes: square pipes are divided into plain carbon steel square pipes and low alloy square pipes according to materials. Plain carbon steel is divided into: Q 195, Q2 15, Q235, SS400, 20# steel, 45# steel, etc. Low alloy steel is divided into Q345, 16Mn, Q390, ST52-3, etc.

3. Square pipes are divided into national standard square pipes, Japanese standard square pipes, British standard square pipes, American standard square pipes, European standard square pipes and non-standard square pipes according to production standards.

4. Square pipes are classified according to their cross-sectional shapes: (1) Square pipes with simple sections-square pipes and rectangular square pipes; (2) Square pipes with complex cross sections-flower-shaped square pipes, open square pipes, corrugated square pipes and special-shaped square pipes.

5. Square pipes are divided into hot-dip galvanized square pipes, electro-galvanized square pipes, oiled square pipes and pickled square pipes according to surface treatment.

6. Square pipes are classified according to their uses-square pipes for decoration, machine tools and equipment, square pipes for mechanical industry, square pipes for chemical industry, square pipes for steel structure, square pipes for shipbuilding, square pipes for automobiles, square pipes for steel beams and columns, and square pipes for special purposes.

7. Rectangular tubes are classified according to wall thickness-ultra-thick-walled rectangular tubes, thick-walled rectangular tubes and thin-walled rectangular tubes.

The above is a detailed introduction to the specifications and classification of galvanized square rectangular pipes. Galvanized rectangular pipes are widely used in buildings, such as fixing, storing and supporting. Choosing the right square tube among different types of square tubes still depends on the use. Zinc in galvanized square pipe has a good protective effect on trimming, scratch and coating wear, and an insoluble oxide layer can be formed on the surface of zinc, which can play a role of barrier protection in many cases.