Description
Direct Mill Supply, Zero Broker Markup — ASTM A500 Gr.B hollow structural sections produced and fabricated under one roof, shipped with full heat-number traceability from our own steel mill.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | ASTM A500 Square and Rectangular Steel Tube |
| Product Type | Square and Rectangular Steel Tube (Hollow Structural Section) |
| Steel Grade | ASTM A500 Gr.B, S235, S275, S355, STK400, Q235B, Q345B |
| Standard | ASTM A500, ASTM A53, GB/T 3091 |
| Section Shape | Square / Rectangular |
| Size Range | 19mm×19mm – 800mm×800mm |
| Wall Thickness | 1 – 30 mm |
| Length | 5.8m / 6m / 11.8m / 12m / Random Length |
| Technique | ERW (Welded) / Seamless |
| Surface Treatment | Black Painting / Galvanized / Varnish / Bare |
| Tolerance | ±1% |
| Ends | Plain |
| Application | Steel structures / Construction frames / Building structures / Curtain wall / Support tubes / Machinery / Scaffolding |
| MOQ | 5 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Commercial & Industrial Construction | Building frames, warehouse portal frames, mezzanine floor beams |
| Infrastructure & Belt & Road Projects | Bridge support columns, highway gantry structures, utility pole bases |
| Machinery & Equipment Manufacturing | Conveyor frames, crane booms, heavy equipment skids |
| Scaffolding & Temporary Works | Scaffold uprights, ledger tubes, shore posts |
What Wall-Thickness Tolerance Costs on a Structural Frame Order
A ±1% tolerance on a 10mm wall is the difference between passing SGS re-inspection and having a full container held at Jebel Ali.
When overseas buyers outsource hollow structural sections to China, the most common dispute is not about steel grade — it is about wall thickness. A supplier quoting by theoretical weight may push negative tolerance to the edge, and when a third-party inspector pulls random tubes off the bundle, the measured values no longer match the mill certificate. The result is a customs hold, a re-inspection bill, and a project schedule that slips by weeks. On an ASTM A500 square and rectangular steel tube order for a warehouse frame, even a 0.3mm shortfall on a 6mm wall can trigger rejection under AISC inspection criteria [NEED_CITE: AISC Code of Standard Practice for material inspection requirements].
Matching Hollow Section Profiles to Structural Load Paths
ASTM A500 square and rectangular steel tube profiles from 19×19mm up to 800×800mm cover the full spectrum of structural framing — from secondary bracing and curtain wall supports to primary portal frame columns. The square section delivers equal moment resistance on both axes, making it the default choice for compression members and column grids, while the rectangular section optimizes section modulus in the direction of primary bending, reducing steel tonnage on beam spans. For EPC contractors sourcing from China, having both shapes available from a single mill means one purchase order, one set of mill test certificates, and one quality system covering the entire frame package.
Engineering Compliance and Certification Requirements
Structural hollow sections for international projects must comply with the governing code at the destination — EN 10219 for European markets, ASTM A500 for North America, and GB/T 6728 for domestic Chinese projects that later ship overseas. The steel grade designation on the mill certificate must match the structural engineer’s specification exactly; a substitution from S355 to Q345B may be metallurgically equivalent, but it will fail document review at customs if the certificate does not cross-reference the specified standard [NEED_CITE: steel grade equivalence between EN 10219 and ASTM A500]. Surface treatment selection — black painted, hot-dip galvanized, or bare — must align with the project’s corrosion category, and the coating thickness must be documented in the inspection report. Random-length tubes at 5.8m or 11.8m are optimized for 20ft and 40ft container loading, reducing on-site cutting waste.
Steel Grade Selection and Manufacturing Process
The ASTM A500 Gr.B grade specified for North American projects delivers a minimum yield strength that sits between the European S235 and S275 grades, while S355 and Q345B serve heavier load applications where higher yield reduces section size and overall weight. Our mill produces both ERW welded and seamless ASTM A500 square and rectangular steel tube — ERW for standard structural framing where cost efficiency matters, and seamless for applications requiring higher pressure integrity or critical load paths. The wall thickness range of 1–30mm covers everything from light-gauge purlins to heavy built-up columns, and the ±1% dimensional tolerance ensures that connection plates and bolt holes align on site without field modification. For galvanized applications, the steel chemistry is controlled to prevent reactive elements from causing excessive zinc consumption during hot-dip coating, preserving both corrosion protection and dimensional accuracy.
Hidden Costs of Incorrect Material Procurement
Ordering the wrong steel grade or accepting excessive negative tolerance creates costs that do not appear on the purchase order. A tube that fails dimensional inspection at the destination port triggers re-testing fees, storage charges, and potential rejection — all of which fall on the buyer when the original mill certificate cannot be verified. Material traceability gaps between the steel producer and the fabricator mean that when a structural engineer requests a specific heat number, the paperwork chain breaks, and the entire batch may be deemed non-conforming [NEED_CITE: EN 10219 cold-formed hollow section traceability requirements]. The cost of re-fabricating a column because the wall thickness was 0.5mm under spec is always higher than the cost of verifying tolerance before shipment.
Why Buyers Source ASTM A500 Tube From Our Mill
Our facility operates three dedicated production lines for hollow structural sections, with raw steel produced in-house — meaning the chemical composition on every mill test certificate originates from our own melt shop, not a third-party trader’s paperwork. We maintain over 2,800 specifications in stock, so a mixed order of 200×200×8 columns and 150×100×6 beams ships from one location with unified documentation. Every ASTM A500 square and rectangular steel tube leaving the warehouse passes through ultrasonic wall-thickness verification, and we welcome SGS or BV third-party inspection at any stage. Our welding procedures and welder qualifications are certified to AWS and EN standards, and the complete quality package — WPS, PQR, weld maps, dimensional reports, and coating thickness records — travels with every shipment.
Documentation & Compliance
- Mill test certificate documenting ASTM A500 Gr.B chemical composition and mechanical properties per heat number
- CE certificate confirming EN 10219 compliance for European market customs clearance
- ISO 9001 quality management system certificate covering the full production process
- SGS or BV third-party inspection report available for wall thickness, coating, and dimensional verification
- Material traceability report linking each bundle to its original heat number and production date
- Export documentation including packing list, bill of lading, and certificate of origin
Packaging, Loading & Delivery
- ASTM A500 square and rectangular steel tubes bundled with steel strips and seaworthy packaging, sized for 5.8m and 11.8m lengths to maximize 20ft and 40ft container payload
- Galvanized tubes protected with edge guards and plastic wrapping to prevent zinc coating damage during ocean transit
- Black painted and bare tubes bundled with waterproof covers for humidity-sensitive destinations in Southeast Asia and the Middle East
- Random-length and cut-to-order tubes marked with heat number, steel grade, and size on each piece for on-site identification
- FOB, CIF, and DDP shipping terms available, with professional lashing plans for oversized 800×800mm sections
Requesting a Quotation for Your Project
Submit your structural drawings or bill of materials specifying steel grade, section size, wall thickness, length, surface treatment, and destination port — we respond within 24 hours with pricing, mill test certificate samples, and a production schedule. For non-standard sizes or mixed container loads, we provide a detailed packing plan showing how your order fills the container.
Get Your ASTM A500 Quote With Full Mill Certification
Send your specifications to receive pricing and material documentation within one business day.
Contact: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Email: admin@xjystructure.com
Mobile/WhatsApp/WeChat: +86 188 5315 7756
