stainless steel
square pipe & tube
Stainless steel pipe & tube is all we do. ASTM A554 square tube from 10×10 to 300×300 mm in 304 and 316L with controlled corner radii, satin or mirror finishes protected by film, and trial orders from 100–300 kg; EN 1.4062 lean duplex made to order.
To support design validation, pilot fabrication, and architectural mockups, TeCarve supports 100 – 300 kg flexible trial orders for standard and custom square section sizes. Every order includes full EN 10204 3.1 Mill Test Certificates and direct workshop traceability.
Structural & Architectural Stainless Steel Square Tubing: Controlled R-Corners
ASTM A554 square tubes from 10×10 mm to 300×300 mm in 304, 316L, and EN 1.4062 (made to order), with uniform satin finish and protective film.
Specifications
ASTM A554 & International Standards Specification Matrix
Scope & Market: N. America & Global — Welded stainless steel mechanical & architectural square tubing (ASTM A554 Table 5 & Table 6)
| Section Size (mm & in) | Standard WT | Side Dimension Tol. | WT Tolerance | Max Outside Corner Radius | Theor. Weight (kg/m) |
|---|---|---|---|---|---|
| 10×10 mm (0.394"×0.394") | 1.0 mm (0.039") | ±0.38 mm (±0.015") | ±10.0% | Max 3.0t (3.0 mm) | 0.28 kg/m |
| 12×12 mm (0.472"×0.472") | 1.0 mm (0.039") | ±0.38 mm (±0.015") | ±10.0% | Max 3.0t (3.0 mm) | 0.35 kg/m |
| 15×15 mm (0.591"×0.591") | 1.2 mm (0.047") | ±0.38 mm (±0.015") | ±10.0% | Max 3.0t (3.6 mm) | 0.53 kg/m |
| 20×20 mm (0.787"×0.787") | 1.2 mm (0.047") | ±0.38 mm (±0.015") | ±10.0% | Max 3.0t (3.6 mm) | 0.72 kg/m |
| 25×25 mm (0.984"×0.984") | 1.5 mm (0.059") | ±0.38 mm (±0.015") | ±10.0% | Max 3.0t (4.5 mm) | 1.12 kg/m |
| 30×30 mm (1.181"×1.181") | 1.5 mm (0.059") | ±0.38 mm (±0.015") | ±10.0% | Max 3.0t (4.5 mm) | 1.36 kg/m |
| 40×40 mm (1.575"×1.575") | 1.5 mm (0.059") | ±0.51 mm (±0.020") | ±10.0% | Max 3.0t (4.5 mm) | 1.84 kg/m |
| 50×50 mm (1.969"×1.969") | 2.0 mm (0.079") | ±0.51 mm (±0.020") | ±10.0% | Max 2.5t (5.0 mm) | 3.04 kg/m |
| 60×60 mm (2.362"×2.362") | 2.0 mm (0.079") | ±0.51 mm (±0.020") | ±10.0% | Max 2.5t (5.0 mm) | 3.68 kg/m |
| 75×75 mm (2.953"×2.953") | 2.5 mm (0.098") | ±0.76 mm (±0.030") | ±10.0% | Max 2.5t (6.25 mm) | 5.71 kg/m |
| 80×80 mm (3.150"×3.150") | 3.0 mm (0.118") | ±0.76 mm (±0.030") | ±10.0% | Max 2.5t (7.5 mm) | 7.30 kg/m |
| 100×100 mm (3.937"×3.937") | 3.0 mm (0.118") | ±0.76 mm (±0.030") | ±10.0% | Max 2.5t (7.5 mm) | 9.21 kg/m |
| 120×120 mm (4.724"×4.724") | 4.0 mm (0.157") | ±0.76 mm (±0.030") | ±10.0% | Max 2.0t (8.0 mm) | 14.56 kg/m |
| 150×150 mm (5.906"×5.906") | 4.0 mm (0.157") | ±1.52 mm (±0.060") | ±10.0% | Max 2.0t (8.0 mm) | 18.39 kg/m |
- Side Dimensions: Flat dimension limits per Table 5 (±0.38 to ±1.52 mm).
- Wall Thickness: Permissible variation ±10% measured ≥0.5" (13 mm) from corners (Table 6).
- Corner Radius: Conforms to Table 7 (commercial 1.5t–2.0t; sharp architectural corners ≤1.0t available).
- Straightness & Squareness: Straightness ≤ 1.7 mm/m (1/16" in 3 ft); squareness 90° ± 1.5°.
- Supply Length / Form: Fixed lengths 1–12 m (standard 6.0 m); precision cut-to-length (±1.0 mm) available
- Available Grades: MT 304, MT 304L, MT 316, MT 316L, MT 201 (austenitic series)
- Surface Finishes: Mill (2B/No.1), 180–320 Grit Brushed/Satin, 600–800 Grit Mirror Polish (Ra ≤ 0.1 μm) with protective PE laser film
- Corner Radius Options: Standard radius (1.5t–2.0t), sharp architectural corner (≤1.0t), and large ergonomic radius (2.5t–3.0t)
- Dimensional Limits: Per standard tables (Side ±0.38 to ±1.52 mm, WT ±10%), Straightness ≤ 1.7 mm/m, Squareness 90° ± 1.5°
Scope & Market: Europe — Welded stainless steel tube for general engineering & structural hollow sections
| Size (mm) | WT (mm) | Side Tol. | WT Tol. | Corner Radius | Theor. Weight (kg/m) |
|---|---|---|---|---|---|
| 10×10 | 1.0 | ±0.20 mm (±2.0%) | ±0.13 mm (±12.5%) | 1.5t – 2.5t | 0.28 kg/m |
| 20×20 | 1.5 | ±0.20 mm (±1.0%) | ±0.19 mm (±12.5%) | 1.5t – 2.5t | 0.88 kg/m |
| 30×30 | 1.5 | ±0.30 mm (±1.0%) | ±0.19 mm (±12.5%) | 1.5t – 2.5t | 1.36 kg/m |
| 40×40 | 2.0 | ±0.40 mm (±1.0%) | ±0.25 mm (±12.5%) | 1.5t – 2.5t | 2.42 kg/m |
| 50×50 | 2.0 | ±0.50 mm (±1.0%) | ±0.25 mm (±12.5%) | 1.5t – 2.5t | 3.04 kg/m |
| 60×60 | 2.5 | ±0.60 mm (±1.0%) | ±0.31 mm (±12.5%) | 1.5t – 2.5t | 4.55 kg/m |
| 80×80 | 3.0 | ±0.80 mm (±1.0%) | ±0.38 mm (±12.5%) | 1.5t – 2.5t | 7.30 kg/m |
| 100×100 | 3.0 | ±1.00 mm (±1.0%) | ±0.38 mm (±12.5%) | 1.5t – 2.5t | 9.21 kg/m |
- Supply Length / Form: Fixed lengths 1–12 m (standard 6.0 m); precision cut-to-length (±1.0 mm) available
- Available Grades: MT 304, MT 304L, MT 316, MT 316L, MT 201 (austenitic series)
- Surface Finishes: Mill (2B/No.1), 180–320 Grit Brushed/Satin, 600–800 Grit Mirror Polish (Ra ≤ 0.1 μm) with protective PE laser film
- Corner Radius Options: Standard radius (1.5t–2.0t), sharp architectural corner (≤1.0t), and large ergonomic radius (2.5t–3.0t)
- Dimensional Limits: Per standard tables (Side ±0.38 to ±1.52 mm, WT ±10%), Straightness ≤ 1.7 mm/m, Squareness 90° ± 1.5°
Scope & Market: Japan, Southeast Asia — Stainless steel tube for machine & architectural structural purposes
| Size (mm) | WT (mm) | Side Tol. | WT Tol. | Corner Radius | Theor. Weight (kg/m) |
|---|---|---|---|---|---|
| 15×15 | 1.2 | ±0.20 mm (±1.3%) | ±0.15 mm (±12.5%) | 1.5t – 2.5t | 0.53 kg/m |
| 20×20 | 1.2 | ±0.20 mm (±1.0%) | ±0.15 mm (±12.5%) | 1.5t – 2.5t | 0.72 kg/m |
| 25×25 | 1.6 | ±0.25 mm (±1.0%) | ±0.20 mm (±12.5%) | 1.5t – 2.5t | 1.19 kg/m |
| 40×40 | 1.6 | ±0.40 mm (±1.0%) | ±0.20 mm (±12.5%) | 1.5t – 2.5t | 1.95 kg/m |
| 50×50 | 2.3 | ±0.50 mm (±1.0%) | ±0.29 mm (±12.5%) | 1.5t – 2.5t | 3.47 kg/m |
| 75×75 | 2.3 | ±0.75 mm (±1.0%) | ±0.29 mm (±12.5%) | 1.5t – 2.5t | 5.27 kg/m |
| 100×100 | 3.2 | ±1.00 mm (±1.0%) | ±0.40 mm (±12.5%) | 1.5t – 2.5t | 9.79 kg/m |
- Supply Length / Form: Fixed lengths 1–12 m (standard 6.0 m); precision cut-to-length (±1.0 mm) available
- Available Grades: MT 304, MT 304L, MT 316, MT 316L, MT 201 (austenitic series)
- Surface Finishes: Mill (2B/No.1), 180–320 Grit Brushed/Satin, 600–800 Grit Mirror Polish (Ra ≤ 0.1 μm) with protective PE laser film
- Corner Radius Options: Standard radius (1.5t–2.0t), sharp architectural corner (≤1.0t), and large ergonomic radius (2.5t–3.0t)
- Dimensional Limits: Per standard tables (Side ±0.38 to ±1.52 mm, WT ±10%), Straightness ≤ 1.7 mm/m, Squareness 90° ± 1.5°
Scope & Market: Asia-Pacific — Stainless steel welded structural & decorative tubes
| Size (mm) | WT (mm) | Side Tol. | WT Tol. | Corner Radius | Theor. Weight (kg/m) |
|---|---|---|---|---|---|
| 12×12 | 1.0 | ±0.20 mm (±1.7%) | ±0.13 mm (±12.5%) | 1.5t – 2.5t | 0.35 kg/m |
| 20×20 | 1.2 | ±0.20 mm (±1.0%) | ±0.15 mm (±12.5%) | 1.5t – 2.5t | 0.72 kg/m |
| 30×30 | 1.5 | ±0.30 mm (±1.0%) | ±0.19 mm (±12.5%) | 1.5t – 2.5t | 1.36 kg/m |
| 40×40 | 2.0 | ±0.40 mm (±1.0%) | ±0.25 mm (±12.5%) | 1.5t – 2.5t | 2.42 kg/m |
| 60×60 | 2.5 | ±0.60 mm (±1.0%) | ±0.31 mm (±12.5%) | 1.5t – 2.5t | 4.55 kg/m |
| 80×80 | 3.0 | ±0.80 mm (±1.0%) | ±0.38 mm (±12.5%) | 1.5t – 2.5t | 7.30 kg/m |
| 120×120 | 4.0 | ±1.20 mm (±1.0%) | ±0.50 mm (±12.5%) | 1.5t – 2.5t | 14.56 kg/m |
- Supply Length / Form: Fixed lengths 1–12 m (standard 6.0 m); precision cut-to-length (±1.0 mm) available
- Available Grades: MT 304, MT 304L, MT 316, MT 316L, MT 201 (austenitic series)
- Surface Finishes: Mill (2B/No.1), 180–320 Grit Brushed/Satin, 600–800 Grit Mirror Polish (Ra ≤ 0.1 μm) with protective PE laser film
- Corner Radius Options: Standard radius (1.5t–2.0t), sharp architectural corner (≤1.0t), and large ergonomic radius (2.5t–3.0t)
- Dimensional Limits: Per standard tables (Side ±0.38 to ±1.52 mm, WT ±10%), Straightness ≤ 1.7 mm/m, Squareness 90° ± 1.5°
Unlike tier-1 state mills requiring 3–10 tonne minimums, TeCarve supports 100 – 300 kg flexible pilot batches for standard and custom square tubing. Fast CAD/DWG drawing evaluation, custom tooling support, and complete heat-batch material traceability reports.
Square Pipe & Tube vs. Oval Pipe & Tube: Design & Specification Guide
Evaluating profile geometry for architectural balustrades, handrails, or structural framing? Our detailed comparison guide evaluates moment of inertia (Ix vs Iy), torsional stiffness, ergonomic grip comfort, 90° miter welding vs curved jointing, and procurement economics.
TeCarve operates under certified ISO 9001:2015, ISO 14001:2015, and ISO 45001:2018 management systems. Every square tubing order is supplied with an authentic EN 10204 3.1 Mill Test Certificate (MTC) verifying heat chemical analysis, mechanical tensile/yield properties, and dimensional/straightness compliance. Third-party inspection and witness testing (SGS, BV, TÜV) are available upon client request.
Compare profile selection with our Stainless Steel Rectangular Pipe & Tube and Stainless Steel Oval Pipe & Tube.
Evaluating moment of inertia and bending stiffness across directional axes? Read our engineering guide: Square Pipe & Tube vs Rectangular Pipe & Tube: Key Differences.
Get Your Square Tube Quote
Sourcing stainless steel square tubing for structural frameworks, cleanroom equipment, architectural balustrades, or machine frames? Contact our export sales desk for live mill pricing, tight corner radius control, custom cut lengths, and trial orders (100–300 kg MOQ supported).
Consistent corner radii (R-factor) and high torsional rigidity across 10x10 mm up to 300x300 mm dimensions.
Short square tube samples available for corner radius verification, miter welding checks, and surface finish assessment.
Test robotic welding jigs, laser tube cutters, or assembly brackets with low-MOQ trial quantities before volume orders.
recording tensile strength, yield properties, weld seam integrity, and grit polish finishes (180#, 240#, 320#, 400#, mirror).
Standards
→ Scroll right for full chemistry & mechanical data
| Grade | US (UNS) | EN (W.Nr.) | Japan (JIS) | China (GB/T) | C % (Max) | Si % (Max) | Mn % (Max) | P % (Max) | S % (Max) | Cr % | Ni % | Mo % | Tensile σb (Min.) | Yield σ0.2 (Min.) | Elongation (Min.) | Hardness (Max) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 304 | S30400 | 1.4301 | SUS304 | 06Cr19Ni10 | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 18.0-20.0 | 8.0-11.0 | — | 515 MPa (75 ksi) | 205 MPa (30 ksi) | 35% | ≤92 HRB / ≤215 HV |
| 304L | S30403 | 1.4307 | SUS304L | 022Cr19Ni10 | 0.030 | 0.75 | 2.00 | 0.045 | 0.030 | 18.0-20.0 | 8.0-12.0 | — | 485 MPa (70 ksi) | 170 MPa (25 ksi) | 35% | ≤92 HRB / ≤215 HV |
| 316 | S31600 | 1.4401 | SUS316 | 06Cr17Ni12Mo2 | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 16.0-18.0 | 10.0-14.0 | 2.0-3.0 | 515 MPa (75 ksi) | 205 MPa (30 ksi) | 35% | ≤95 HRB / ≤215 HV |
| 316L | S31603 | 1.4404 | SUS316L | 022Cr17Ni12Mo2 | 0.030 | 0.75 | 2.00 | 0.045 | 0.030 | 16.0-18.0 | 10.0-14.0 | 2.0-3.0 | 485 MPa (70 ksi) | 170 MPa (25 ksi) | 35% | ≤95 HRB / ≤215 HV |
| 321 | S32100 | 1.4541 | SUS321 | 06Cr18Ni11Ti | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 17.0-19.0 | 9.0-12.0 | — | 515 MPa (75 ksi) | 205 MPa (30 ksi) | 35% | ≤95 HRB / ≤215 HV |
| 430 | S43000 | 1.4016 | SUS430 | 10Cr17 | 0.12 | 1.00 | 1.00 | 0.040 | 0.030 | 16.0-18.0 | — | — | 450 MPa (65 ksi) | 205 MPa (30 ksi) | 22% | ≤89 HRB / ≤200 HV |
- Standards Conformance: ASTM A554/A312 · EN 10296-2/10210-1 · JIS G3446/G3466 · GB/T 18705/19228 · ISO 2037
- Delivery Condition: Solution Annealed & Pickled (AP) / Bright Annealed (BA) / Polished, or as requested.
- Mill Test Certificate: 100% full material traceability with EN 10204 3.1 MTC provided with every shipment.
Features
• High strength-to-weight ratio
• Aesthetic surface finish options
• Excellent resistance to corrosion and wear
• Suitable for welding and fabrication
• Building and architectural structures
• Furniture and decorative frames
• Industrial frameworks and bracing
• Equipment enclosures and racks
Applications
For structural square tube applications, see how buyers can verify our roll-forming lines, corner-squareness checks, mechanical testing, and batch inspection reports.
Quality Control
• Visual and dimensional inspection
• Surface finish and weld seam testing
• Mechanical property testing (tensile, hardness)
• Optional third-party certification
Structural Square Tubing: EN 1.4062 (Lean Duplex 2202) & High Strength 316 Selection Guide
When structural load-bearing capacity, deflection control, and atmospheric corrosion resistance dictate project requirements, conventional annealed austenitic square tubes may require excessive wall thicknesses. Specifying EN 1.4062 square tube (Lean Duplex 2202 / UNS S32202) or work-hardened high strength 316 square tube delivers superior yield strength, higher allowable design stress under international structural codes, and optimal strength-to-weight economics.
EN 1.4062 is a low-nickel lean duplex stainless steel combining high mechanical strength with excellent resistance to general and chloride-induced stress corrosion. Conforming to EN 10088-2, EN 10088-4, EN 10219-2 (cold formed welded structural hollow sections), and ASTM A240/A276.
- Chemical Matrix (wt% per EN 10088-2): Cr: 21.0–22.0% | Ni: 1.35–1.70% | Mn: 4.00–6.00% | N: 0.20–0.25% | Mo: 0.10–0.80% | C: ≤0.040%
- Mechanical Strength: Minimum Yield Strength (Rp0.2) ≥ 450 MPa (over 2× higher than standard 304/316 at ~205–220 MPa); Tensile Strength Rm: 650–850 MPa; Elongation A5 ≥ 30%.
- Corrosion Index: PREN ≈ 26 (Cr + 3.3Mo + 16N), exceeding 304L and rivaling 316L, while low nickel content provides exceptional material price stability.
Typical Applications: Architectural pedestrian bridges, solar tracker frames, canopies, structural glass curtain wall supports, and lightweight commercial vehicle chassis.
While annealed 316L provides standard yield strength around 220 MPa, cold roll-forming and controlled cold-draw strain hardening elevate high strength 316 square tube to structural-grade load-bearing capabilities while preserving marine-grade pitting corrosion resistance.
- Cold-Work Hardened Properties: Strain-hardened yield strength reaches Rp0.2 ≥ 450 – 600+ MPa with ultimate tensile strength Rm ≥ 700 – 850+ MPa, matching or exceeding structural carbon steel.
- Marine Pitting Resistance: Retains 2.0%–3.0% Molybdenum content (PREN 23–25) to resist severe pitting and crevice attack in coastal marine salt air and industrial splash zones.
- Ductility & Toughness: Preserves ≥20% elongation, supporting energy absorption and fatigue resistance under dynamic wind or seismic loads.
Typical Applications: Coastal curtain wall mullions, offshore platform structural framework, pharmaceutical cleanroom load-bearing skids, and impact-resistant balustrades.
Mechanical & Engineering Comparison Matrix
| Steel Grade / Designation | Microstructure | Yield Strength (Rp0.2) | Tensile Strength (Rm) | PREN Index | Primary Engineering Advantage |
|---|---|---|---|---|---|
| EN 1.4062 (Lean Duplex 2202) | Dual-phase Ferrite / Austenite (~50/50) | ≥ 450 – 530 MPa | 650 – 850 MPa | ~26 | Maximum strength-to-cost efficiency; 40% weight reduction; chloride SCC immunity. |
| High Strength 316 (Strain-Hardened) | Austenitic (Cold-work hardened) | ≥ 450 – 600+ MPa | 700 – 850+ MPa | ~23 – 25 | Exceptional marine pitting resistance combined with heavy structural load-bearing capacity. |
| Standard 304 / 304L (Annealed) | 100% Austenitic | ≥ 205 MPa | 515 – 700 MPa | ~18 – 19 | Standard architectural decoration, indoor handrails, furniture, and light framing. |
| Standard 316 / 316L (Annealed) | 100% Austenitic | ≥ 220 MPa | 520 – 720 MPa | ~23 – 25 | Standard marine trim, chemical transfer, and moderate-load coastal fabrication. |
packaging
PVC Wrapping
& End Caps
Custom Barcoding
& Labeling
Anti-Corrosion
& Moisture Protection
Seaworthy Wooden Cases & Pallets
Square Tube Packaging & Inspection Photos
Real product, inspection, packaging and loading photos.
Tailored Solutions, Timely Fulfillment
CUSTOMIZATION
& DELIVERY
Flexible Custom Manufacturing
We tailor stainless steel square pipe and tube by square section size, wall thickness, custom length, grade, polished, mirror, brushed, or pickled finish, tube type, and dimensional tolerance.
Low MOQ & Rapid Prototyping
Small batch customization and sample production are supported, helping you shorten your development cycle and market entry.
Optimized Lead Time
In-stock standard sizes ship within 7–10 days. Custom specifications typically ship within 10–25 days after deposit, depending on order volume, dimensions, and surface finish. The full cycle—from inquiry and drawing confirmation through sampling, production, inspection, and dispatch—typically takes 33–55 days for custom items.
Global Logistics & On-Time Delivery
For square tube deliveries worldwide, seaworthy wooden cases and pallets support the profiles while custom barcoding and labeling keeps bundled sizes identifiable.
How your order is made, checked and shipped
Tube forming at the partner factory
Heat treatment (annealing)
Dimensional inspection
Alloy verification with a handheld analyzer
Export packing
Container loading
What Global Buyers Say About TeCarve Tubing
“I've received the goods and everything is fine.”
“The goods already send to customers. I am waiting for the next order from them.”
“…there is no need of inspection this time… I trust in your product.”
Frequently Asked Questions
What are stainless steel square tubes used for?
Stainless steel square tubes are used in structural frameworks, handrails, furniture, architectural facades, food processing equipment, conveyor systems, and industrial supports where corrosion resistance is required alongside structural rigidity.
What sizes are available for stainless steel square tube?
TeCarve supplies square tubes from 10×10 mm to 300×300 mm with wall thickness 0.5 mm to 6 mm. Standard length is 6 m; cut-to-length is available. Grades 201, 304, and 316L in welded or seamless construction.
What surface finishes are available for stainless steel square tube?
Available finishes: No. 1 (hot rolled), 2B (cold rolled mill), No. 4 (brushed/satin), No. 8 (mirror), and PVD-coloured (gold, black, rose gold). Mirror finish square tube is widely used for decorative architectural and display applications.
What dimensional tolerances apply to stainless steel square tube?
Tolerances follow EN 10219 or ASTM A554: side-dimension tolerance ±0.5% or ±0.5 mm (whichever is greater), wall-thickness tolerance +15%/–10%, straightness ≤ 2 mm/m. Tighter precision tolerances are available for structural or precision machine applications.
Can custom corner radius stainless steel square tube be produced?
Yes. External corner radius typically ranges from 1.5t to 3t (where t = wall thickness). Sharp-corner square tube for architectural use and large-radius corner tube for sanitary or ergonomic applications are produced to customer specifications.
Can I order small quantities of structural square tubes?
Yes. We accommodate trial and replenishment orders from 100–300 kg for standard square tubes. Cut-to-length service is provided with protective film wrapping.
Can TeCarve supply EN 1.4062 (Lean Duplex) square tubing?
Yes, on a made-to-order basis. EN 1.4062 lean duplex square tubing offers high yield strength and stress corrosion resistance. Supply parameters: 20×20 to 200×200 mm, WT 1.5–8.0 mm, MOQ 3–5 tons (strip slitting minimum), lead time 35–45 days.
How are square tube corner radii and surface protection controlled?
Corner radii are controlled per ASTM A554 to ensure uniform welding alignment. Each finished tube is wrapped with protective film to prevent scratches during transport.
Contact TeCarve