Arc-Welded Square & Rectangular Tubing

Arc-welded square and rectangular steel tubing is manufactured by forming high-quality steel plates or steel strips into square or rectangular cross-sections and welding the longitudinal joints through advanced electric arc welding processes. This method is exceptionally advantageous when structural designs require high tensile strength, extreme wall thicknesses, or specialized steel alloys.

During the entire welding process, key parameters—such as welding current, voltage, and travel speed—are strictly controlled to guarantee deep joint penetration and prevent thermal deformation or weld defects. Known for high mechanical strength and excellent material plasticity, arc-welded hollow sections are widely used in heavy-duty applications, including structural construction, machinery manufacturing, shipbuilding, and automotive engineering.

Key Features & Advantages

Exceptional Load-Bearing Capacity: The structural weld joint efficiency is highly reliable, with weld strength consistently reaching over 90% of the parent material’s tensile strength.

Ultra-Heavy Wall Thickness Customization: While we offer standard wall thicknesses up to 12.0mm, our advanced welding facility can customize specialized thick-walled square tubing with wall thicknesses equal to or greater than 50mm (≥50 mm) for critical load requirements.

Complete Joint Penetration (CJP): Capable of achieving full-penetration welds, ensuring maximum structural integrity at high-stress node connections and heavy-duty structural columns.

Broad Material Versatility: Tubing can be manufactured using standard carbon structural steels, atmospheric corrosion-resistant weathering steels, or food-grade stainless steels depending on the corrosive threats of the installation environment.

Technical Specifications & Parameter Ranges

Our arc-welded square and rectangular steel tubing complies with strict dimensional and physical requirements defined under international standards:

Parameter	Specification Details
International Standards	ASTM A500, EN 10219, JIS G3466
Square Tube Dimensions	20mm × 20mm to 200mm × 200mm (Non-standard dimensions customizable)
Rectangular Tube Dimensions	20mm × 30mm to 120mm × 200mm (Non-standard dimensions customizable)
Standard Wall Thickness	1.5 mm to 12.0 mm
Special Wall Thickness	Customizable heavy-walled sections up to ≥50 mm
Length Options	Standard lengths of 6m, 9m, 12m, or Custom engineered lengths
Welding Process	Heavy-duty Electric Arc Welding (with full parameter monitoring)

Dimensional Range Details

Square Tubing Side Dimensions

To support diverse architectural and industrial frameworks, we supply square profiles in typical outer dimensions, including:
· 20mm × 20mm, 30mm × 30mm, 40mm × 40mm, 50mm × 50mm, 60mm × 60mm
· 80mm × 80mm, 100mm × 100mm, 120mm × 120mm, 150mm × 150mm, 200mm × 200mm
· Customization: Non-standard side dimensions can be custom-rolled and welded to match exact project blueprints.

Rectangular Tubing Side Dimensions

Our rectangular hollow sections offer directional loading support and are available in various standard sizes:
· 20mm × 30mm, 30mm × 40mm, 40mm × 60mm, 50mm × 80mm
· 60mm × 100mm, 80mm × 120mm, 100mm × 150mm, 120mm × 200mm

Wall Thickness (WT) Configurations

We supply a versatile range of wall thicknesses depending on the load environment of your structural application:
· Standard Thicknesses: 1.5mm, 2.0mm, 2.5mm, 3.0mm, 4.0mm, 5.0mm, 6.0mm, 8.0mm, 10.0mm, 12.0mm
· Heavy-Duty Customization: For massive structural foundations, mechanical columns, or marine structures, we can manufacture specialized sections with wall thicknesses of ≥50 mm.

Custom Length Capacities

Our standard inventory and production runs focus on standard lengths of 6 meters, 9 meters, and 12 meters. However, we can customize unique lengths to suit specific large-scale construction frameworks or heavy equipment integration, minimizing on-site butt-joint welding and optimizing installation efficiency.

Primary Application Fields

Construction & Civil Infrastructure: Used as structural columns, high-rise architectural skeletons, heavy-duty trusses, and bridge support systems where full weld penetration is crucial.

Heavy Machinery Manufacturing: Applied as structural components, mounting beds, and main frames for heavy cranes, mining machinery, and material handling equipment.

Automotive & Heavy Vehicle Industry: Installed in automobile frames, heavy truck chassis, and towing structures requiring exceptional weld fatigue limits.

Shipbuilding & Marine Engineering: Selected for highly stressed ship structural framing, deck structures, and offshore platform supports requiring thick-walled profiles.

Frequently Asked Questions (FAQ)

Q: What are the benefits of full-penetration (CJP) welds in arc-welded square tubes?

A: Complete Joint Penetration (CJP) welds ensure that the weld metal fuses completely across the entire thickness of the steel plate joint. This eliminates internal voids or root cracks, allowing the welded joint to transfer heavy structural loads smoothly. CJP welds provide maximum joint strength, making these tubes highly suitable for rigid node connections and heavy-duty seismic structural designs.

Q: Can Cangtie supply custom thick-walled square sections beyond standard sizes?

A: Yes. While standard square hollow sections generally peak at a wall thickness of 12.0mm, our specialized arc welding fabrication lines are capable of cold-forming and welding heavy-gauge plates. This allows us to manufacture specialized thick-walled square and rectangular profiles with wall thicknesses of ≥50 mm tailored to high-load structural projects.

Q: How are welding parameters controlled to prevent deformation in thick-wall sections?

A: Controlling thermal distortion is critical when arc-welding thick-walled sections. Our technicians strictly regulate the heat input by automating and monitoring the welding current, arc voltage, and travel speed. When welding heavy-gauge plates, we utilize specialized welding sequences and pre-heating procedures to distribute thermal stresses evenly, preventing distortion and ensuring the structural straightness of the final hollow section.