SPA-H rectangular steel tube is a high-performance weathering steel hollow section manufactured to JIS G3125 standards. Engineered for structural, architectural, and industrial applications, these products provide exceptional atmospheric corrosion resistance, high tensile strength, and significant long-term maintenance savings.

SPA-H rectangular steel tube

Unlike standard carbon steel, SPA-H weathering steel develops a dense, stable protective oxide layer (patina) upon exposure to the environment. This natural barrier inhibits further oxidation, eliminating the requirement for protective coatings and reducing the total lifecycle cost of the structure.

Key Advantages of SPA-H Weathering Steel Hollow Sections

1. Atmospheric Corrosion Resistance
The primary feature of SPA-H steel is its self-protecting capability. The protective rust layer:

• Prevents deep-seated corrosion by sealing the steel surface.

• Regenerates naturally if the surface sustained mechanical damage.

• Reduces maintenance requirements, making it ideal for inaccessible or high-altitude structures.

2. Optimized Strength-to-Weight Ratio
Rectangular hollow sections (RHS) provide superior load-bearing efficiency compared to open profiles. When manufactured from SPA-H steel, they offer:

• Increased structural stability with reduced material thickness.

• High yield strength (≥ 355 MPa) for demanding engineering projects.

• Enhanced resistance to torsional stress and bending.

3. Architectural and Aesthetic Value
The evolving earth-toned finish of SPA-H steel offers a modern, industrial aesthetic that blends harmoniously with natural landscapes. It requires no painting, powder coating, or galvanizing, preserving its raw, organic appearance over decades.

Technical Specifications of SPA-H Weathering Steel Hollow Sections

Chemical Composition (%)

The precise alloying of Copper, Chromium, and Nickel ensures the formation of the protective patina.
| Element | C | Si | Mn | P | S | Cu | Cr |
| :— | :— | :— | :— | :— | :— | :— | :— |
| Content | ≤ 0.12 | 0.25–0.75 | 0.20–0.50 | 0.07–0.15 | ≤ 0.035 | 0.25–0.55 | 0.30–1.25 |

Mechanical Properties

SPA-H vs. S275J0H

Product Range and Availability of SPA-H Weathering Steel Hollow Sections

We provide a comprehensive selection of sizes and custom processing options to meet specific project requirements.

• Wall Thickness: 0.5 mm – 25 mm

• Standard Lengths: 6000 mm / 12000 mm (Custom lengths available)

• Production Methods: Hot Rolled (HR) / Cold Rolled (CR)

• Surface Finishes: Natural rust, pre-weathered, or protective oiling.

Size and Weight Reference (Partial Table):
| Dimensions (mm) | Weight ( kg/m ) | Dimensions (mm) | Weight ( kg/m ) |
| 40 × 20 × 2.5 | 2.03 | 100 × 50 × 5.0 | 10.90 |
| 60 × 40 × 4.0 | 5.72 | 150 × 100 × 6.0 | 22.30 |
| 80 × 50 × 4.0 | 7.34 | 300 × 200 × 10.0 | 75.00 |
| 100 × 50 × 3.0 | 6.75 | 400 × 200 × 16.0 | 142.00 |

Primary Applications of SPA-H Weathering Steel Hollow Sections

• Infrastructure: Pedestrian bridges, highway sound barriers, and railway frameworks.

• Architecture: Building facades, landscape sculptures, and urban furniture.

• Industrial Equipment: Conveyor systems, hopper liners, and shipping containers.

• Heavy Machinery: Mining equipment, excavator structures, and dump truck bodies.

As a leading manufacturer and exporter of SPA-H weathering steel, we offer integrated supply chain solutions including:

• Mill-Direct Sourcing: Competitive pricing and guaranteed material origin.

• Quality Assurance: Full Material Test Certificates (MTC) provided with every shipment.

• Precision Processing: Advanced laser cutting, plasma cutting, and custom welding services.

• Global Logistics: Export-grade seaworthy packaging and efficient international shipping.

Contact our technical sales team for current pricing, detailed datasheets, and project support.

What is spa H material?

JIS G3125 SPA-H is a Japanese standard for hot rolled weathering steel plate. It offers superior corrosion resistance compared to carbon steel grades. As Spa-h steel coil material is a weathering steel, it forms the protective patina on the surface which gives it a rustic appearance.

What does spah mean?

Secondary pulmonary arterial hypertension (SPAH) is an adverse outcome of a variety of systemic disorders. These include collagen vascular diseases, chronic thromboembolism, human immunodeficiency virus, portopulmonary hypertension, and other diseases.