Classification of square steel tube

Square steel tubes are widely used in various industries due to their versatility and structural integrity. They can be categorized based on several factors, such as production process, material, production standards, cross-sectional shape, surface treatment, and their intended application. Below is a detailed breakdown of the different classifications.

Craft Classification

Square steel tubes are classified by their production methods:

Hot-rolled seamless square tubes

Cold-drawn seamless square tubes

Extruded seamless square tubes

Welded square tubes

Welded square tubes can be further subdivided:

By process: arc welded, resistance welded (high frequency, low frequency), gas welded, and furnace welded square tubes.

By welding seam type: straight seam welded and spiral welded square tubes.

Material Classification

Square steel tubes are also categorized based on the material:

Plain carbon steel square tubes include grades such as Q195, Q215, Q235, SS400, 20# steel, and 45# steel.

Low alloy square tubes feature materials like Q345, 16Mn, Q390, and ST52-3.

Production Standard Classification

Production standards define the specifications of square tubes, including:

National standard square tubes

Japanese standard square tubes

Imperial square tubes

American standard square tubes

European standard square tubes

Non-standard square tubes

Section Shape Classification

Square tubes can be grouped by their cross-sectional shape:

Simple cross-section: square or rectangular tubes.

Complicated cross-sections: flower-shaped, open-shaped, corrugated, or other special-shaped square tubes.

Surface Treatment Classification

Surface treatments are applied for durability and protection:

Hot-dip galvanized square tubes

Electro-galvanized square tubes

Oil-coated square tubes

Pickled square tubes

Application Classification

Square tubes serve various functions depending on their intended use:

For decoration

For machine tools

For the machinery industry

For the chemical industry

For steel structures

For shipbuilding

For automobiles

For steel beams and columns

For special purposes

Wall Thickness Classification

Lastly, square tubes are categorized based on their wall thickness:

Super thick-walled square tubes

Thick-walled square tubes

Thin-walled square tubes

These classifications allow for precise selection based on the specific requirements of a project or application.