Description
Factory-Direct Stainless Square Tubes — Every 201 304 316 stainless steel square pipe batch runs through our in-house lab in Jinan before container sealing, with original mill test certificates traceable by heat number.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | 201/304/316 Stainless Steel Square Pipe |
| Product Type | Square / Rectangular Stainless Steel Tube (Welded, Polished) |
| Steel Grade | 201, 202, 304, 304L, 304H, 310S, 309S, 316, 316L, 317L, 321, 904L, 2205, 2507, 2520, 410, 410S, 420, 430, 431, 440A, SAF2304, S31500, S31803, S32900, S31260, S32750, S32550 |
| Standard | AISI, ASTM, BS, DIN, GB, JIS, EN |
| Section Shape | Square / Rectangular |
| Size Range | 10×10mm – 150×150mm |
| Wall Thickness | 0.1mm – 80mm |
| Length | 2000mm / 2440mm / 2500mm / 3000mm / 3048mm / 5800mm / 6000mm |
| Technique | Cold Rolled / Hot Rolled / Cold Drawn; Welded (ERW) |
| Surface Treatment | BA / 2B / NO.1 / NO.3 / NO.4 / 8K / HL / 2D / 1D |
| Tolerance | ±1% |
| Ends | Plain / Custom |
| Application | Construction / Building / Industry / Foodstuff / Gas / Metallurgy / Biology / Electronics / Chemical / Petroleum / Boiler / Nuclear Energy / Medical Equipment / Fertilizer |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Architecture | Decorative facade frames, handrail posts, curtain wall support structures |
| Chemical & Petroleum | Corrosion-resistant piping for 316L/904L process lines and heat exchanger casings |
| Food & Beverage | Hygienic 304/316L square tubes for processing equipment frames and conveyor guides |
| Medical & Nuclear | High-purity polished 304/316 tubes for imaging equipment housings and cleanroom structures |
| Electronics & Metallurgy | Precision 201/304 square tubes for equipment enclosures and furnace component frames |
Why a 201 Grade Mixed Into Your 304 Order Can Cost You 45 Days
Nickel content is the silent variable — and visual inspection will not catch it.
Back when I was on the procurement side for a Dubai mall facade project, we ordered polished 304 stainless steel square pipes. The mill certs looked perfect, but SGS on-site testing showed the nickel content was 201-grade — barely 1%. The whole container got rejected, 45 days of delay, and the client nearly walked. That kind of grade substitution happens when suppliers blend stock from multiple mills without heat-number traceability. [NEED_CITE: stainless steel grade verification methods for nickel and chromium content] When you source a 201 304 316 stainless steel square pipe from a single certified factory with in-house lab testing, every batch is verified against its declared grade before it leaves the floor.
Matching Stainless Square Tubes to Structural and Decorative Engineering
A 201 304 316 stainless steel square pipe must align with both the load-bearing demands and the environmental exposure of its installation point. For interior architectural applications like handrails and facade mullions, 201 or 304 with NO.4 or HL hairline finish provides adequate corrosion resistance at lower cost. Once the environment shifts to coastal, chemical, or food-processing zones, 316L and 904L become necessary to resist chloride pitting and acid attack. Our production lines in Jinan cover the full range from 10×10mm decorative tubes to 150×150mm structural sections, with cold drawn precision holding ±1% tolerance — critical when square tubes must mate with laser-cut connection plates on site.
Engineering Compliance and Surface Finish Selection
Structural stainless square tubes used in load-bearing frames must conform to recognized standards such as ASTM A500 or EN 10219 for cold-formed hollow sections, depending on the destination market. [NEED_CITE: EN 10219 cold-formed stainless steel hollow section requirements] Surface finish selection directly affects both corrosion performance and project acceptance: BA and 8K mirror finishes serve decorative and cleanroom applications, while 2B and NO.1 suits industrial and chemical environments where appearance is secondary. For European projects, CE certification under EN 10210/10219 is mandatory for customs clearance — missing documentation can hold a container at port for weeks. Custom lengths from 2000mm to 6000mm reduce on-site cutting waste, and our processing services include bending, welding, punching, and cutting to project-specific dimensions before shipment.
Steel Grade Mechanics and Manufacturing Process
The 200 series (201, 202) uses manganese-nitrogen substitution for partial nickel replacement, offering lower cost for indoor decorative use where corrosion demands are minimal. The 300 series — 304, 304L, 316, 316L — maintains full austenitic structure with 8–12% nickel, delivering reliable formability and corrosion resistance across construction, food, and chemical applications. Duplex grades like 2205 and 2507 combine austenitic and ferritic phases for superior chloride stress-corrosion cracking resistance in offshore and marine environments. ERW welded production keeps costs competitive for standard sizes while cold drawn processing achieves the tight ±1% tolerance that structural connections demand. Surface treatments from NO.4 brushed to 8K mirror are applied after forming, ensuring uniform finish across all four faces and corners of the square profile.
Hidden Costs of Unverified Stainless Steel Procurement
Ordering a 201 304 316 stainless steel square pipe without verified mill test certificates creates risks that surface only at project inspection. Grade substitution — 201 shipped as 304 — leads to premature corrosion failure in outdoor or chemical environments, triggering warranty claims and structural remediation. Missing CE or EN certification blocks customs clearance in European markets, adding demurrage charges and schedule delays. Excessive negative tolerance on wall thickness reduces load capacity below design specifications, failing structural engineer sign-off. [NEED_CITE: consequences of material non-conformance in structural steel procurement] Every batch we ship carries original mill test certificates with heat-number traceability, and SGS/BV third-party inspection is available before container sealing.
Procurement Confidence from a Verified Stainless Tube Source
As a factory-direct manufacturer operating three production lines in Jinan, we eliminate the markup and quality opacity that come with trading intermediaries. Our in-house理化实验室 tests chemical composition and mechanical properties on every heat, producing original mill test certificates before any 201 304 316 stainless steel square pipe leaves the facility. We maintain ready stock across 2,800+ specifications covering square and rectangular sections from 10×10mm to 150×150mm, enabling urgent orders without waiting for mill production runs. ISO 9001:2015, Lloyd’s CE (EN 10210/10219), and FPC certifications ensure compliance for European and international projects. Custom orders — non-standard sizes, special lengths, specific surface finishes — run on typical production lead times with full processing services including bending, punching, and cutting. Our export team handles container loading optimization, documentation, and customs paperwork for shipments to 50+ countries.
Documentation & Compliance
- Mill test certificate documenting 304/316L chemical composition (Ni, Cr, Mo content) and mechanical properties per ASTM A500 or EN 10219
- CE certificate under EN 10210/EN 10219 for structural hollow sections entering European Union markets
- ISO 9001:2015 quality management certificate covering production and inspection processes
- SGS or BV third-party inspection report verifying grade, dimensions, and surface finish before shipment
- Full material traceability by heat number linking each 201 304 316 stainless steel square pipe bundle to its production batch
- Export customs documents including packing list, bill of lading, and certificate of origin
Packaging, Loading & Delivery
- Polished 201 304 316 stainless steel square pipes bundled with steel strips and wrapped in waterproof paper with edge protectors to preserve BA/8K/HL surface finish during ocean transit
- Seaworthy standard packaging with anti-rust paper interleaving for NO.4 and mirror finish tubes, preventing surface scratches between layers
- Container loading optimization for 6000mm lengths in 20ft and 40ft containers, maximizing payload while protecting polished surfaces from contact damage
- Custom cutting to 2000mm–3048mm project-specific lengths available, reducing on-site waste and handling
- Heat number and steel grade marked on each bundle tag, enabling site verification against mill test certificates
- FOB, CIF, and DDP shipping terms with professional export documentation handling for door-to-port or door-to-door delivery
Start Your Stainless Square Pipe Inquiry
Submit your specifications — steel grade, section size, wall thickness, surface finish, quantity, and destination port — and receive a competitive bulk quotation within 12 hours. We will include mill test certificate samples, third-party inspection options, and container loading plans tailored to your project timeline.
Request Your 201 304 316 Stainless Steel Square Pipe Quote
Send your specifications via email or WhatsApp to receive factory-direct pricing, available stock confirmation, and mill test certificate samples within one business day.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.sdxinjiyuan.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxinjiyuan.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
Frequently Asked Questions
Q: What is the difference between 201, 304, and 316 stainless steel square pipes for my project?
A: 201 stainless steel uses manganese-nitrogen to partially replace nickel, offering lower cost for indoor decorative applications with minimal corrosion exposure. 304 provides full austenitic corrosion resistance suitable for most construction, food, and general industrial environments. 316 and 316L add molybdenum for superior resistance to chloride pitting, making them necessary for coastal, chemical processing, and marine applications.
Q: Which surface finish should I specify for architectural versus industrial use?
A: For architectural and decorative applications such as facades, handrails, and interior structures, NO.4 brushed, HL hairline, or 8K mirror finishes provide the required aesthetic appearance. For industrial, chemical, or food processing applications where appearance is secondary to corrosion resistance, 2B or NO.1 finishes are cost-effective and functionally appropriate.
Q: Can you produce non-standard sizes and custom lengths? What is the MOQ?
A: Yes, we produce custom square and rectangular sizes within the 10×10mm to 150×150mm range with wall thickness from 0.1mm to 80mm. Custom lengths from 2000mm to 6000mm are available. The MOQ is 1 ton, supporting both trial orders and full-container bulk procurement.
Q: How do you ensure material traceability and grade compliance?
A: Every batch of 201 304 316 stainless steel square pipe carries an original mill test certificate documenting chemical composition and mechanical properties, traceable by heat number. Our in-house lab conducts three-stage inspection before shipment. SGS or BV third-party inspection is available on request for independent verification.
Q: What certifications do your stainless steel square tubes carry for international markets?
A: Our production is ISO 9001:2015 certified, and structural products carry Lloyd’s CE certification under EN 10210/EN 10219 for European market compliance. FPC certification is also available. Complete export documentation including certificate of origin, packing list, and bill of lading is provided with every shipment.
