Galvanized Square and Rectangular Tubes

Galvanized square and rectangular tubes is a hollow rectangular tube made of steel and coated with a layer of zinc to prevent corrosion. The galvanizing process involves dipping the steel into a molten zinc solution, which creates a bond between the zinc and the steel, forming a protective layer on its surface.
These tubes are commonly used in construction and industrial applications such as building framing, scaffolding, fencing and other structural applications. They are durable and galvanized for excellent protection against rust and corrosion, making them ideal for use in outdoor environments.
Schematic diagram of the processing of Galvanized square and rectangular tubes :

The characteristics of galvanized square and rectangular tubes:
Galvanized square and rectangular tubes has several properties that are well suited for industrial applications. It has a lower initial cost than stainless steel and has a long service life, making it ideal for applications in harsh environments. Thanks to the galvanized coating, this rectangular tube is strong enough to resist damage from assembly and handling.
(1) Strong anti-corrosion performance: During the production process, the outer surface of the square tube and rectangular tube will be galvanized to form a zinc layer on the surface. The thickness and quality of the zinc layer have a great influence on the anticorrosion performance of the steel pipe. Generally speaking, the greater the thickness of the zinc layer, the better the anti-corrosion performance, but the excessive thickness of the zinc layer will also affect the durability of the steel pipe.
(2) Strong acid and alkali resistance: the surface of the galvanized rectangular tube has a certain acid and alkali resistance, which can be used in an acid and alkali environment and is not easy to be corroded.
(3) Beautiful and practical: Galvanized square and rectangular tubes is made of galvanized material, with smooth surface, bright color, not easy to fade, beautiful and generous; it also has good wear resistance and toughness, and is safe and reliable to use.

Application of galvanized square and rectangular tubes:
(1) Construction field: Galvanized square and rectangular tubes are also widely used in construction and decoration. For example, partitions, display racks, chairs, doors, steel and wood floor grids, etc., are beautiful and practical.
(2) Agricultural field: In modern agriculture, rectangular tubes are used more and more widely. For example, steel frame greenhouses, fruit and vegetable sheds, etc. are all made of square tubes.
(3) Industrial field: It is also widely used in the industrial field. For example, oil, gas and other water well pipes, air pipes, filter materials, etc. are all made of square rectangular pipes.
In short, the galvanized square and rectangular tubes has the characteristics of corrosion resistance, wear resistance and good toughness. It is widely used in construction, agriculture, industry and other fields. It is an economical and practical material.

The following are the national standards of China, Britain, the United States and Japan:

Chinese national standard
GB/T 13237-2013 "High-quality Carbon Structural Steel Cold-rolled Plates and Strips", GB/T 34201-2017 "Square and Rectangular Hot-Rolled Seamless Steel Tubes for Structural Use"

British standard
BS 1387 "Heavy welded galvanized steel pipe", BS 1139 "Specification for metal pipe scaffolding"

American standard:
ASTM A500 "Standard Specification for Cold-Formed Welded and Seamless Carbon Steel Structural Pipe", ASTM A53 "Seamless and Welded Black and Galvanized Steel Pipe"

Japanese standard
JIS G 3466: "Carbon steel parts for square steel tubes"

This standard specifies the order content, dimensions, shape and weight, technical requirements, inspection and test methods, inspection rules, packaging, marks and quality certificates of square and rectangular hot-rolled seamless steel pipes for structural use.

The deviation of galvanized square and rectangular tubes specifications generally includes outer diameter, wall thickness, length and so on. The reason is mainly due to the precision limitation of the process and equipment in the manufacturing and the physical influence in the process of transportation and storage, etc.

Outer diameter: 10*10mm – 500*500mm;
Wall thickness: 0.5mm – 20mm;
Length: 0.1 – 18m.

In view of various situations of specification deviation of galvanized square and rectangular tubes, the Chinese national standard GB/T 3091-2015 "Welded Steel Pipe" stipulates the allowable deviation range, the specific content is as follows:
1. Outer diameter deviation: ±0.5%D, where D is the outer diameter of the square tube.
2. Wall thickness deviation: should meet the following requirements:
(1) When the wall thickness is ≤0.5mm, the allowable deviation is ±0.1mm;
(2) When the wall thickness is >0.5mm, the allowable deviation is ±10% of the wall thickness.
3. Length deviation: The allowable deviation is ±5mm of the pipe length.

The content of the above specifications stipulates the allowable maximum deviation of the specification deviation of galvanized square and rectangular tubes under different circumstances. Strictly following the national standards can effectively guarantee product quality and use effect, and ensure building quality and construction safety.