Square Tube

Square tube standard:

ASTM A500 Grade B,

ASTM A513 (1020-1026)

ASTM A36 (A36)

EN 10210:S235,S355,S235JRH,

S355J2H,S355NH
EN 10219:S235,S355,S235JRH,

S275J0H, S275J2H, S355J0H, S355J2H

Square tube size:

Production process:

The manufacturing process of square hollow sections (SHS) can generally be divided into two categories based on the raw materials and forming route: Hot Rolled Square Tube Production Process and Cold Rolled/Cold Formed Square Tube Production Process.

Hot rolled square tube:

Hot-rolled square steel tubes are square steel pipes or hollow square steel sections manufactured using a high-temperature rolling process. The production temperature is typically between 900°C and 1250°C, where deformation and forming are completed in the metal's high-temperature plastic state. This process is suitable for producing thick-walled, large-size, and high-strength structural square tubes.

Cold rolled square tube:

Cold-rolled square steel tubes (also known as cold-formed square tubes) generally refer to square tube products manufactured using a cold bending forming process, and most of them belong to the commonly seen ERW welded square steel tubes in the market. This process is carried out continuously at room temperature and features high efficiency, high precision, and good surface quality.

Chemical composition

Mechanical properties

Main types of square steel tubes

Square steel tubes (SHS) can be classified according to manufacturing process, material, surface treatment, and application.

1. Classified by manufacturing process

Hot rolled square tube: Produced using a high-temperature rolling process, it has good load-bearing capacity and thick-wall processing capability, suitable for bridges, heavy steel structures, and large-scale engineering projects.

Cold formed/ERW square tube: Manufactured through cold bending and high-frequency welding, it is the most common type of square tube on the market, characterized by high dimensional accuracy, high production efficiency, and good surface quality.

Seamless square tube: Usually made from seamless round tubes through cold drawing or hot working, it has no weld seams, good pressure resistance, and is commonly used in high-pressure equipment, machining, and special industrial fields.

2. Classified by material

Carbon steel square tube: Common materials include Q235, Q355, and ASTM A500, widely used in construction, machinery, and structural engineering.

Stainless steel square tube: Made of 304, 316, and other stainless steels, offering excellent corrosion resistance, suitable for chemical, food, decorative, and marine environments.

Alloy steel square tube: Contains alloying elements such as Cr, Mo, and Ni, providing higher strength, heat resistance, or corrosion resistance, used in special working conditions.

3. Classified by surface treatment

Black square tube: Without special surface treatment, lower cost, mostly used for general structural applications.

Galvanized square tube: Includes pre-galvanized and hot-dip galvanized square tubes, offering strong corrosion resistance, suitable for outdoor structures, fencing, greenhouses, and conveyor systems.

Coated/Painted square tubes: Surface painting, powder coating, or anti-corrosion treatment can enhance weather resistance and decorative effect.