Description
Factory-Direct Hollow Sections — 0.5–200 mm wall range produced on dedicated lines with in-house bending and cutting.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q195-Q460 Carbon Steel Square/Rectangular Pipe |
| Product Type | Square / Rectangular Steel Tube (Hollow Section) |
| Steel Grade | Q195, Q235, Q235B, Q345, Q345B, Q460, SS330, SS400, SS540 |
| Standard | ASTM |
| Section Shape | Square, Rectangular, Round |
| Size Range | Wall thickness 0.5–200 mm |
| Length | 12 m (39.37 ft) |
| Technique | Cold Rolled / Hot Rolled |
| Surface Treatment | Galvanized / Bare / Oiled / Non-oiled per requirement |
| Tolerance | ±1% |
| Ends | As per customer requirement |
| Processing Services | Welding, Punching, Cutting, Bending, Decoiling |
| Invoicing | By Theoretical Weight |
| Package | Standard Seaworthy Packing |
| Application | Fluid Pipe, Boiler Pipe, Drill Pipe, Hydraulic Pipe, Gas Pipe, Steel Structures, Construction Frames, Machinery, Scaffolding |
| MOQ | 5 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| EPC Contractors | Steel structure frames for industrial plants and infrastructure |
| Machinery Manufacturers | Hydraulic and fluid conveyance systems requiring precision tubes |
| Construction Companies | Scaffolding, building frames, and structural supports |
| System Integrators | Conveyor structures and automation frames |
What Wall-Thickness Tolerance Costs on a Structural Frame Order
A ±1% tolerance on a 200 mm wall Customized Square Rectangular Hollow Steel Pipe is the difference between a frame that passes inspection and one that fails load calculations.
When procurement teams source hollow sections from fragmented suppliers, wall thickness often drifts into negative tolerance territory. On paper, theoretical weight invoicing looks economical — until the material arrives and third-party inspectors flag under-wall sections against EN 10219 or ASTM A500 requirements [NEED_CITE: EN 10219 cold-formed hollow section dimensional tolerances]. The result is re-cutting, re-welding, or outright rejection at the project site. With Q195 through Q460 grades spanning 0.5 to 200 mm wall, precision matters equally for light scaffolding and heavy hydraulic frames.
Matching Q195–Q460 Grades to Structural and Pressure Applications
A Customized Square Rectangular Hollow Steel Pipe in Q235B handles general building frames and scaffolding where formability and weldability take priority. Step up to Q345B or Q460 when the design demands higher yield capacity for load-bearing columns or crane booms. For hydraulic and fluid lines, SS400 and SS540 grades provide the tensile consistency needed under internal pressure. Our in-house bending and cutting services mean these tubes arrive on site pre-processed to drawing dimensions, eliminating secondary fabrication at the yard.
Engineering Compliance Across EN, ASTM, and JIS Frameworks
Structural engineers specifying EN 1993 or AISC frameworks need hollow sections that map cleanly to recognized standards. Q-series grades correspond broadly to S-series and ASTM equivalents [NEED_CITE: steel grade equivalence between EN and ASTM standards], but project consultants must verify chemical composition and mechanical properties per batch. CE certification under EN 10210/EN 10219 is mandatory for EU-bound shipments, while ASTM-marked material clears North American customs without delay. Our in-house physical and chemical laboratories issue mill test certificates per heat number, and third-party SGS or BV inspection is available before dispatch.
Why Cold Rolled and Hot Rolled Techniques Matter for Surface and Precision
Cold rolled Customized Square Rectangular Hollow Steel Pipe delivers tighter dimensional accuracy and smoother surface finish — critical for visible architectural frames or precision machinery mounts. Hot rolled sections suit heavy structural work where absolute surface perfection is secondary to load capacity. Surface treatment choice follows the environment: galvanized finish for coastal or chemical-exposed sites, oiled or bare for indoor structural use, and non-oiled when subsequent painting or powder coating is planned. Wall thickness up to 200 mm covers everything from thin-wall conveyor frames to thick-wall drill pipe and hydraulic cylinders.
The Hidden Cost of Unverified Steel Grades and Missing Certificates
Ordering Q345B hollow sections that arrive with Q235 chemistry means the structure carries less load than engineered — a safety liability that surfaces only during inspection or under stress. Missing CE or EN certificates trigger customs holds at EU ports, turning a routine delivery into a multi-week delay [NEED_CITE: customs clearance requirements for CE-marked structural steel]. Negative tolerance drift beyond ±1% inflates theoretical weight invoicing while reducing actual section modulus. These are not abstract risks; they are the reason EPC contractors now demand mill test certificates and third-party inspection before container sealing.
Procurement Confidence from a Certified Hollow Section Manufacturer
As a national high-tech enterprise with 41 patented technologies — including proprietary sharp-corner rectangular tube manufacturing — we produce Customized Square Rectangular Hollow Steel Pipe across 2,800+ specifications on three dedicated lines. Every batch passes through our in-house physical and chemical laboratories before release. We hold ISO 9001:2015, Lloyd’s Register EU CE (EN 10210/EN 10219), Singapore FPC, and SGS/BV verification. Factory-direct pricing eliminates trading margins, and exports to 50+ countries across EU, North America, India, Southeast Asia, and the Middle East confirm our logistics and documentation capability.
Documentation & Compliance
- Mill test certificate documenting Q195–Q460 chemical composition and mechanical properties per heat number
- CE certificate under EN 10210/EN 10219 for EU project compliance and customs clearance
- ISO 9001:2015 quality management certificate covering production and inspection processes
- SGS or BV third-party inspection report available upon request for independent quality verification
- Material traceability by heat number linked to mill test certificate and packing list
- Customs documents including packing list, bill of lading, and certificate of origin
Packaging, Loading & Delivery
- Q195–Q460 square and rectangular tubes bundled with steel strips and edge protectors to preserve galvanized or bare surface finish during ocean transit
- 12 m standard length or custom cut-to-size loaded with layered timber separators to prevent zinc coating abrasion and tube deformation
- Container loading optimized by our logistics team for 0.5–200 mm wall sections, maximizing weight utilization within 20ft and 40ft units
- Heat number and steel grade stenciled on each bundle for site traceability and inspection matching
- FOB, CIF, and DDP shipping options with door-to-door delivery to 50+ countries including EU, North America, and Southeast Asia ports
Start Your Hollow Section Procurement With Verified Specifications
Submit your Customized Square Rectangular Hollow Steel Pipe requirements — steel grade, wall thickness, quantity, and destination port — and receive a detailed quotation with mill test certificate preview within 12 hours. Non-standard dimensions and custom processing (bending, cutting, punching, welding) are quoted separately with confirmed lead times.
Request a Quotation With Mill Test Certificate
Send your specifications to admin@sdxjysteel.com or contact us via WhatsApp at +86 188 5315 7756. Our international team responds within half a day with pricing, certification confirmation, and loading plan.
Frequently Asked Questions
Q: How do Q235 and Q345 grades compare to ASTM A500 or EN S355JR?
A: Q235 and Q345 are Chinese standard grades with yield strength and chemical composition broadly aligned to ASTM A500 Grade B and EN S355JR respectively. Exact equivalence depends on the specific project specification, and we provide mill test certificates per heat number so your engineer can verify compliance.
Q: What is the MOQ for customized non-standard dimensions beyond your catalog?
A: Our standard catalog covers 2,800+ specifications with wall thickness from 0.5 to 200 mm. For non-standard sizes outside this range, MOQ is negotiated based on production line setup and typically starts at 5 tons.
Q: When should I specify galvanized versus oiled or bare surface treatment?
A: Galvanized finish is recommended for outdoor, coastal, or chemically exposed environments where corrosion resistance is critical. Oiled or bare finish suits indoor structural applications or projects where subsequent painting or powder coating is planned.
Q: Do you provide CE and EN certificates for European Union projects?
A: Yes. Our Customized Square Rectangular Hollow Steel Pipe carries CE certification under EN 10210 and EN 10219, verified by Lloyd’s Register. Full documentation package including mill test certificates and customs documents is provided for EU clearance.
Q: How do you optimize container loading for heavy steel tubes?
A: Our logistics team prepares detailed loading plans for each order, balancing weight distribution and maximizing container utilization. Layered timber separators and edge protectors prevent surface damage and deformation during transit, with real-time tracking available throughout shipment.
