Description
Factory-Direct Pricing, No Middlemen — Every hot rolled carbon steel square rectangular hollow section ships directly from our 3 production lines in Jinan, eliminating distributor markups on orders from 1 Ton to full project volumes.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Carbon Steel Hot Rolled Square and Rectangular Hollow Section |
| Product Type | Square and Rectangular Steel Tube (Hollow Section) |
| Steel Grade | Carbon Steel |
| Section Shape | Square / Rectangular |
| Size Range | Square 12×12–800×800 mm; Rectangular 10×20–800×1000 mm |
| Length | 1–12 m |
| Technique | Hot Rolled |
| Surface Treatment | Bare / Oiled / Black Painting / Galvanized |
| Application | Hospital, School, Mall, Supermarket, Warehouse, Workshop, Farmhouse, Courtyard, Structure Pipe |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Commercial Construction | Column frames and roof trusses for malls, supermarkets, hospitals, and schools |
| Industrial Facilities | Load-bearing portal frames for warehouses, workshops, and farmhouses |
| Infrastructure & EPC | Structural bracing and support columns for courtyard enclosures and public buildings |
Where Negative Tolerance Failures Cost You an Entire Container
Wall-thickness shortfalls measured at destination port trigger full-cargo rejection — not partial claims.
I once inspected a 40×80 rectangular hollow section order bound for Jebel Ali: the purchase spec called for 2.5 mm wall, but caliper checks across the bundle showed readings below 2.0 mm. The negative tolerance had been pushed so aggressively that third-party re-inspection at port failed outright. Twenty-eight tonnes of hot rolled carbon steel square rectangular hollow section sat rejected while the buyer scrambled for replacement material. Since then, every bundle leaving our facility goes through caliper抽检 on each piece before the container doors close. [NEED_CITE: EN 10219 dimensional tolerance requirements for hot rolled hollow sections]
Matching Structural Hollow Sections to Commercial and Industrial Frames
Hot rolled carbon steel square rectangular hollow section profiles in the 12×12 to 800×1000 mm range cover nearly every column, beam, and brace dimension that commercial and industrial building frames demand. The hot rolling process produces uniform wall distribution across flat faces and corners — critical when these sections carry gravity loads through multi-storey mall or hospital structures. Surface options from bare and oiled to galvanized let engineers match corrosion protection to indoor versus exposed courtyard environments without switching suppliers mid-project.
Engineering Compliance and Surface Protection Decisions
Structural hollow sections for public buildings and warehouses must satisfy load-bearing codes such as EN 1993 or AISC equivalents, which reference dimensional and material conformity rather than brand origin. [NEED_CITE: EN 10210 hot finished structural hollow sections compliance requirements] Choosing between bare, oiled, black painted, or galvanized finish depends on whether the section faces indoor dry conditions or outdoor humidity in farmhouse and courtyard applications. Sections destined for EU markets require CE marking under EN 10210/10219, while North American projects reference ASTM equivalents — certification gaps at either end cause customs holds that delay crane schedules. [NEED_CITE: CE marking requirements for structural steel under EN 10210] Custom cut-to-length from 1 to 12 m reduces on-site welding and secondary cutting, lowering labor cost at the erection stage.
Hot Rolling Process and Carbon Steel Behavior
Hot rolling forms the square and rectangular profile at temperatures above the steel’s recrystallization point, which relieves internal stresses and produces consistent mechanical properties across the full cross-section — an advantage over cold-formed alternatives when sections carry primary structural loads. Carbon steel grades used in these hollow sections offer weldability and formability suitable for site connections through bolting or full-penetration welding. Surface treatment selection follows the service environment: oiled or black painted finishes suffice for indoor warehouse frames, while galvanized coating extends service life in humid farmhouse or courtyard exposures. Wall thickness consistency from hot rolling reduces the risk of local buckling under compression, a failure mode that thin-walled cold-formed sections face when negative tolerance is over-exploited. [NEED_CITE: hot rolled versus cold formed hollow section structural behavior comparison]
The Hidden Price of Unverified Mill Certificates
Ordering structural hollow sections without verified mill test certificates means the steel grade claimed on paper may not match the material delivered — a discrepancy that surfaces only during third-party inspection or structural loading. Sections with undocumented chemistry or unconfirmed yield behavior can fail engineering audits, forcing tear-down of erected frames and project-wide re-inspection. Certification gaps also block customs clearance in markets requiring CE or SGS documentation, stranding cargo at port while demurrage charges accumulate. [NEED_CITE: structural steel certification requirements for EU customs clearance] The true cost is never the per-tonne price difference — it is the crane idle time, the re-welding, and the reputation loss with the project owner.
Procurement Confidence Built on Factory Control
Every hot rolled carbon steel square rectangular hollow section we supply passes through our in-house physical and chemical laboratory before shipment — chemistry, tensile behavior, and dimensional checks are completed on-site rather than outsourced. Our 2,800+ specification range covers square sections from 12×12 to 800×800 mm and rectangular sections from 10×20 to 800×1000 mm, meaning non-standard dimensions rarely require separate sourcing from a second supplier. We hold 41 invention patents including proprietary sharp-corner rectangular tube technology, and our CE certification under EN 10210/10219 alongside ISO 9001:2015, SGS, and BV verification documents travel with every shipment. Professional loading plans optimize container weight for sections up to 12 m length, and we ship FOB, CIF, or DDP to 50+ countries with real-time tracking.
Documentation & Compliance
- Mill Test Certificate documenting carbon steel chemical composition and mechanical test results per heat number, traceable to the production batch
- CE certificate confirming conformity with EN 10210 for hot finished structural hollow sections, required for EU market entry
- ISO 9001:2015 quality management certificate covering the full production and inspection process
- SGS or BV third-party inspection report available upon request for destination-port verification
- Material traceability by heat number stamped on each section, linking physical delivery to laboratory records
- Customs document package including packing list, Bill of Lading, and Certificate of Origin for import clearance
Packaging, Loading & Delivery
- Bare and oiled hot rolled sections bundled with steel strips and edge protectors to prevent surface scratching during transit
- Galvanized hollow sections packed with separation layers to preserve zinc coating integrity across ocean shipment
- Custom cut lengths from 1 to 12 m loaded with optimized container stowage plans to maximize weight per shipment
- Heat number and steel grade stenciled on each bundle for site identification and traceability verification
- FOB, CIF, and DDP shipping terms available with door-to-door logistics coordination to 50+ countries
Start Your Procurement with Verified Specifications
Submit your required section dimensions, steel grade, surface treatment preference, quantity, and destination port — we respond within 12 hours with a detailed quotation including unit price, production lead time, and applicable certification documents. Non-standard dimensions and custom cut lengths are confirmed against our 2,800+ specification inventory before contract signing.
Request a Quotation with Mill Test Certificate
Send your specification sheet via email to admin@sdxjysteel.com or contact us on WhatsApp at +86 188 5315 7756 to receive pricing, certification previews, and loading plans.
Frequently Asked Questions
Q: What size range is available for hot rolled carbon steel square and rectangular hollow sections?
A: Square sections cover 12×12 mm to 800×800 mm, and rectangular sections cover 10×20 mm to 800×1000 mm, with lengths from 1 to 12 meters. Over 2,800 specifications are available from stock, and non-standard dimensions can be produced to order.
Q: What surface treatment options are available and how do they affect corrosion resistance?
A: Four options are offered — bare (uncoated, for indoor or painted applications), oiled (short-term rust prevention during transit), black painted (moderate corrosion protection), and galvanized (long-term protection for exposed or humid environments). The choice depends on the installation environment and design service life.
Q: Can you provide CE certification and mill test certificates for EU customs clearance?
A: Yes. All shipments include original Mill Test Certificates with chemical and mechanical data traceable by heat number. CE certification under EN 10210/10219 is provided for EU market compliance, and third-party inspection reports from SGS or BV are available upon request.
Q: What is the minimum order quantity for hot rolled square and rectangular hollow sections?
A: The MOQ is 1 Ton, which accommodates both trial orders for new projects and full-scale procurement for large construction contracts.
Q: What are your delivery terms and how do you handle international shipping?
A: We offer FOB, CIF, and DDP terms with professional container loading plans optimized for section lengths up to 12 m. Shipments are tracked in real time, and we deliver to 50+ countries including the EU, North America, Southeast Asia, and the Middle East.
Secure Your Project Supply with Factory-Direct Pricing and Full Certification
Email your specifications to admin@sdxjysteel.com or message +86 188 5315 7756 on WhatsApp to receive a quotation with mill test certificate previews and container loading plans.
