Description
Factory-Direct Rectangular Hollow Sections — XJY Plate supplies ASTM A500 GR.B rectangular hollow section steel tubes from mill stock in sizes ranging from 15mm×20mm to 700mm×800mm, eliminating intermediary markups and ensuring full traceability from heat number to final delivery.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | ASTM A500 GR.B Rectangular Hollow Section Steel Tube |
| Product Type | Rectangular Steel Tube (RHS) |
| Steel Grade | GR.B, A53(A.B), S235, S275, S355, STK400 |
| Standard | ASTM A500, ASTM A53, GB/T 3091 |
| Section Shape | Rectangular |
| Size Range | 15mm×20mm – 700mm×800mm |
| Wall Thickness | 1 – 30 mm |
| Length | 5.8m / 6m / 11.8m / 12m / Random Length |
| Technique | Welded or Seamless |
| Surface Treatment | Black Painting / Galvanized / Varnish / Bare |
| Tolerance | ±1% |
| Ends | Plain |
| Application | Construction structure / Building frames / Curtain wall / Support tubes / Structural pipe |
| MOQ | 5 Tons |
| Origin | China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Commercial & Industrial Construction | Building frames, portal frames, mezzanine structures |
| Architectural Facades | Curtain wall mullions, canopy support tubes |
| Infrastructure & Civil Engineering | Bridge handrails, highway sign gantries, sound barrier frames |
| Machinery & Equipment | Machine bases, conveyor support structures, crane booms |
| Warehousing & Logistics | Racking uprights, mezzanine columns, support scaffolding |
What Wall-Thickness Tolerance Costs on a Structural Frame Order
A ±1% tolerance on a 30mm wall thickness means the difference between a column that passes load calculation and one that fails inspector sign-off.
Structural engineers specify rectangular hollow sections based on published section properties — moment of inertia, radius of gyration, plastic modulus — all of which depend directly on actual wall thickness. When a supplier ships tubes with uncontrolled negative tolerance, those section properties shrink silently. The frame gets erected, the inspector measures the wall with an ultrasonic gauge, and the entire batch gets rejected. I have seen a 40-foot container of RHS held at port for three weeks because the actual wall thickness fell below the minimum specified in the fabrication drawings. The cost of air-freighting replacement material dwarfed the original order value. [NEED_CITE: EN 10219 cold-formed hollow section dimensional tolerance requirements]
How ASTM A500 GR.B Rectangular Hollow Section Steel Tube Matches Structural Frame Requirements
Rectangular hollow sections in GR.B grade deliver the yield strength range that structural designers expect for moment-resisting frames and braced structures. The 15mm×20mm to 700mm×800mm size range covers everything from secondary purlin supports to primary column members. Welded ERW production suits the majority of architectural and structural applications where internal pressure is absent, while seamless options serve projects demanding higher integrity at critical joints. Each ASTM A500 GR.B rectangular hollow section steel tube ships with a mill test certificate tied to its heat number, so the fabricator can verify chemical composition and mechanical properties before cutting a single piece.
Engineering Compliance and Certification for Rectangular Hollow Sections
Structural steel procurement for commercial buildings and infrastructure projects must satisfy both the designer’s specification and the importing country’s regulatory framework. ASTM A500 governs cold-formed welded and formed seamless structural tubing in North American projects, while EN 10219 applies to cold-formed welded structural hollow sections in European-specification markets. The grade equivalence between GR.B, S275JR, and STK400 allows procurement teams to source from a single ASTM A500 GR.B rectangular hollow section steel tube supplier and satisfy multiple specification systems — provided the mill test certificate documents the full chemical and mechanical data required by each standard. [NEED_CITE: steel grade equivalence mapping between ASTM A500 GR.B and EN 10219 S275JR] Surface treatment selection — black painted for interior structural work, hot-dip galvanized for exterior or corrosive environments — must align with the project’s durability specification and the local building code’s corrosion protection requirements.
Understanding Steel Grades and Production Methods for RHS
The GR.B grade under ASTM A500 specifies a minimum yield strength tier that sits between the lower-strength A53 grades and the higher-strength A500 GR.C, making it the default choice for general structural framing in North American-specification projects. When a project calls for S275 or S355 instead, the yield strength steps up progressively — S355 offers roughly 25% higher yield than S235 — which directly affects the section’s load-bearing capacity and allows designers to reduce member sizes. The welded ERW process produces rectangular hollow sections by forming flat strip into shape and welding the longitudinal seam, which keeps costs competitive for standard structural sizes. [NEED_CITE: comparison of ERW welded versus seamless structural hollow section manufacturing] Surface treatment matters as much as steel grade for long-term performance: hot-dip galvanizing provides sacrificial zinc protection for outdoor structural frames exposed to weather, while black painting or varnish suits interior applications where corrosion risk is minimal. Wall thickness tolerance directly affects theoretical weight calculations — a ±1% tolerance on a 10mm wall means the actual weight per meter can vary, which influences both shipping cost estimates and structural weight assumptions.
The Hidden Costs of Procuring Rectangular Hollow Sections Without Verified Documentation
Ordering ASTM A500 GR.B rectangular hollow section steel tube without confirmed mill test certificates exposes the project to three categories of failure. First, material that does not meet the specified grade’s chemical composition or mechanical properties will fail third-party inspection at the fabrication shop or on-site, triggering costly replacement and schedule delays. Second, importing countries with strict customs documentation requirements may detain or reject shipments lacking traceable heat numbers and certified test reports. [NEED_CITE: customs clearance requirements for structural steel imports with mill test certificates] Third, negative tolerance that exceeds the standard’s allowable range reduces the actual load-bearing capacity of structural members, creating a latent safety risk that may not surface until the building is under load.
Why Procurement Teams Source ASTM A500 GR.B Rectangular Hollow Section Steel Tube from XJY Plate
XJY Plate maintains dedicated stock of rectangular hollow sections across the full 15mm×20mm to 700mm×800mm range in GR.B, S235, S275, S355, and STK400 grades, so procurement teams do not need to split orders across multiple suppliers. Every piece carries an original mill test certificate with heat number traceability, chemical composition, and mechanical test results — not a reprinted summary, but the document the rolling mill issued. The facility holds ISO 9001:2015 and CE certification, and third-party inspection through SGS or BV can be arranged before shipment for projects requiring independent verification. Custom cutting-to-length, bending, and other processing services reduce on-site waste and fabrication time. Professional heavy-cargo logistics experience — including flatbed, open-top container, and break-bulk shipping — ensures that long-length RHS arrives without damage or overweight penalties.
Documentation & Compliance
- Mill test certificate documenting GR.B chemical composition and mechanical properties per ASTM A500, traceable to heat number
- CE certificate confirming conformity with EN 10219 for cold-formed welded structural hollow sections where European market access is required
- ISO 9001:2015 quality management system certificate covering the full supply and inspection process
- SGS or BV third-party inspection report available upon request for projects mandating independent pre-shipment verification
- Material traceability documentation linking each bundle to its heat number, size, grade, and length
- Complete customs documentation including packing list, bill of lading, and certificate of origin for smooth port clearance
Packaging, Loading & Delivery
- Rectangular hollow sections bundled with steel strips and edge protectors to prevent surface damage to galvanized or painted finishes during ocean transit
- Galvanized RHS packed with separation layers to preserve zinc coating integrity and avoid friction marks between adjacent tubes
- Container loading optimized for 5.8m and 6m lengths in standard 20-foot units, with 11.8m and 12m lengths loaded in open-top or flat-rack containers to avoid overhang
- Custom cut-to-length processing available to match fabrication drawings, reducing on-site cutting waste and handling time
- Each bundle marked with heat number, steel grade, size, and length for immediate identification at the fabrication shop
- Shipping terms available as FOB, CIF, or DDP with professional flatbed and break-bulk logistics for heavy structural steel deliveries
How to Request a Quotation for Your Rectangular Hollow Section Project
Submit your required steel grade, outer dimensions, wall thickness, length, quantity, and destination port to receive a detailed quotation including material cost, processing fees, and shipping terms. XJY Plate responds to inquiries within 12 hours and provides the mill test certificate for your quality verification before or with shipment. For non-standard sizes or custom cutting requirements, the technical team will confirm feasibility and lead time based on current mill stock.
Request Your ASTM A500 GR.B Rectangular Hollow Section Steel Tube Quote
Send your specification details to receive pricing, mill test certificates, and delivery scheduling.
Company: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.xjyplate.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@xjyplate.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
Frequently Asked Questions
Q: What is the grade equivalence between ASTM A500 GR.B, EN S275JR, and JIS STK400?
A: These grades occupy similar yield strength tiers in their respective standard systems. GR.B under ASTM A500, S275JR under EN 10219, and STK400 under JIS G3466 all serve general structural applications, though exact chemical composition and mechanical property values differ slightly. XJY Plate provides full mill test certificates with chemical and mechanical data so your engineering team can verify compliance with the specific standard your project requires.
Q: How can I verify the mill test certificate for the rectangular hollow sections I receive?
A: Each bundle of ASTM A500 GR.B rectangular hollow section steel tube ships with an original mill test certificate showing the heat number, chemical composition, and mechanical test results. The heat number is also marked on the bundle itself, allowing direct cross-reference. Third-party inspection through SGS or BV can be arranged before shipment for independent verification.
Q: What is the MOQ policy for custom cut-to-length rectangular hollow sections?
A: The standard minimum order quantity is 5 tons. For custom cut-to-length processing, the team will confirm feasibility based on the required dimensions and quantity. Non-standard sizes outside the 15mm×20mm to 700mm×800mm range can be discussed for production scheduling.
Q: Should I specify galvanized, black painted, or bare surface treatment for my project?
A: Surface treatment selection depends on the installation environment. Hot-dip galvanized RHS is recommended for outdoor structural frames, facades, and any application exposed to weather or corrosive conditions. Black painted or varnished finish suits interior structural work where corrosion risk is minimal. Bare tubes are appropriate when the fabricator will apply their own coating system or when the tubes will be further processed before final surface treatment.
Q: How does wall thickness tolerance affect the theoretical weight and structural capacity of rectangular hollow sections?
A: The specified tolerance is ±1% on wall thickness. Theoretical weight calculations are based on nominal dimensions, so actual weight per meter may vary within this tolerance range. More importantly, actual wall thickness directly determines the section’s structural properties — moment of inertia, section modulus, and load-bearing capacity. XJY Plate maintains strict tolerance control and documents actual measurements on the mill test certificate.
