ASTM A554 stainless steel rectangular tube is the standard specification for welded mechanical tubing made from austenitic stainless steels. Unlike pressure-rated pipes (ASTM A312), ASTM A554 tubes are designed for mechanical and structural applications where aesthetics, dimensional accuracy, and corrosion resistance are key requirements.
These rectangular hollow sections (RHS) are manufactured from stainless steel strip, roll-formed into shape, and longitudinally welded. The result is a cost-effective, dimensionally consistent tube with excellent surface finish options — from industrial mill finish to decorative No.4 brushed and No.8 mirror polish.
Product Specifications
| Parameter |
Details |
| Standard |
ASTM A554 (Standard Specification for Welded Stainless Steel Mechanical Tubing) |
| Product Type |
Rectangular Tube / Rectangular Hollow Section (RHS) |
| Grades |
MT-304, MT-304L, MT-316, MT-316L, MT-201 |
| Construction |
Welded (ERW – Electric Resistance Welded) |
| Outer Dimensions (A × B) |
10mm × 5mm to 200mm × 100mm (0.39″ × 0.20″ to 7.87″ × 3.94″) |
| Wall Thickness |
0.5mm – 5.0mm (0.020″ – 0.197″) |
| Length |
3m – 6m (standard); up to 12m (custom) |
| Surface Finish |
Mill Finish, Pickled, No.4 Brushed, No.8 Mirror Polished |
| Corner Radius |
1.5 × WT maximum (per ASTM A554) |
ASTM A554 Rectangular Tube Available Grades & Designations
| ASTM Grade |
Common Name |
Key Characteristics |
Typical Applications |
| MT-304 |
304 |
General-purpose, good corrosion resistance |
Handrails, furniture, frames |
| MT-304L |
304L |
Low carbon, better weldability |
Welded structures, chemical exposure |
| MT-316 |
316 |
Molybdenum added, chloride resistance |
Marine, coastal, outdoor |
| MT-316L |
316L |
Low carbon 316 |
Marine, pharmaceutical |
| MT-201 |
201 |
Lower nickel, cost-effective |
Decorative, indoor applications |
Note: ASTM A554 does NOT include pressure ratings. For pressure applications, use ASTM A312 (seamless/welded pipe).
Standard Dimensions & Sizes
Small Sizes (10mm – 50mm)
| A × B (mm) |
Wall Thickness (mm) |
Weight (kg/m) – 304 |
Typical Use |
| 10 × 5 |
0.5, 0.8 |
0.22 – 0.35 |
Small frames, models |
| 15 × 10 |
0.8, 1.0, 1.2 |
0.46 – 0.68 |
Handrails, furniture |
| 20 × 10 |
0.8, 1.0, 1.2, 1.5 |
0.54 – 0.98 |
Furniture, display stands |
| 20 × 15 |
1.0, 1.2, 1.5 |
0.68 – 1.02 |
Frames, carts |
| 25 × 15 |
1.0, 1.2, 1.5, 2.0 |
0.84 – 1.34 |
Handrails, gates, trailers |
| 25 × 25 |
1.0, 1.2, 1.5, 2.0 |
1.02 – 1.58 |
Square – furniture, frames |
| 30 × 20 |
1.2, 1.5, 2.0 |
1.28 – 2.06 |
Frames, supports |
| 40 × 20 |
1.5, 2.0, 2.5 |
1.82 – 2.96 |
Machinery frames, racks |
| 40 × 40 |
1.5, 2.0, 2.5 |
2.48 – 3.96 |
Square – structural |
| 50 × 25 |
1.5, 2.0, 2.5 |
2.16 – 3.48 |
Frames, trailers |
| 50 × 50 |
1.5, 2.0, 2.5, 3.0 |
3.14 – 5.02 |
Square – structural |
Medium to Large Sizes (60mm – 200mm)
| A × B (mm) |
Wall Thickness (mm) |
Weight (kg/m) – 304 |
Typical Use |
| 60 × 40 |
2.0, 2.5, 3.0 |
3.68 – 5.42 |
Structural frames |
| 60 × 60 |
2.0, 2.5, 3.0 |
4.28 – 6.28 |
Square columns |
| 80 × 40 |
2.0, 2.5, 3.0 |
4.12 – 6.08 |
Platforms, supports |
| 80 × 60 |
2.5, 3.0, 4.0 |
5.86 – 8.94 |
Heavy frames |
| 80 × 80 |
2.5, 3.0, 4.0 |
7.04 – 10.68 |
Square columns |
| 100 × 40 |
2.5, 3.0, 4.0 |
6.12 – 9.48 |
Beams, lintels |
| 100 × 50 |
2.5, 3.0, 4.0 |
6.48 – 10.02 |
Structural |
| 100 × 80 |
3.0, 4.0, 5.0 |
9.46 – 15.08 |
Heavy structural |
| 100 × 100 |
3.0, 4.0, 5.0 |
10.68 – 16.88 |
Square columns |
| 120 × 60 |
3.0, 4.0, 5.0 |
9.86 – 15.72 |
Beams, frames |
| 150 × 100 |
4.0, 5.0 |
18.42 – 22.36 |
Heavy structural |
| 200 × 100 |
4.0, 5.0 |
22.68 – 27.88 |
Heavy beams |
Custom dimensions available upon request
Chemical Composition (ASTM A554 Requirements)
| Grade |
C |
Mn |
Si |
Cr |
Ni |
Mo |
P |
S |
| MT-304 |
≤0.08 |
≤2.00 |
≤1.00 |
18.0-20.0 |
8.0-11.0 |
– |
≤0.045 |
≤0.030 |
| MT-304L |
≤0.030 |
≤2.00 |
≤1.00 |
18.0-20.0 |
8.0-12.0 |
– |
≤0.045 |
≤0.030 |
| MT-316 |
≤0.08 |
≤2.00 |
≤1.00 |
16.0-18.0 |
10.0-14.0 |
2.0-3.0 |
≤0.045 |
≤0.030 |
| MT-316L |
≤0.030 |
≤2.00 |
≤1.00 |
16.0-18.0 |
10.0-14.0 |
2.0-3.0 |
≤0.045 |
≤0.030 |
| MT-201 |
≤0.15 |
5.5-7.5 |
≤1.00 |
16.0-18.0 |
3.5-5.5 |
– |
≤0.045 |
≤0.030 |
Mechanical Properties (ASTM A554 Requirements)
| Grade |
Tensile Strength (MPa) |
Yield Strength (MPa) |
Elongation (%) |
Hardness (HRB max) |
| MT-304 |
≥515 |
≥205 |
≥35 |
≤90 |
| MT-304L |
≥485 |
≥170 |
≥35 |
≤90 |
| MT-316 |
≥515 |
≥205 |
≥35 |
≤95 |
| MT-316L |
≥485 |
≥170 |
≥35 |
≤95 |
| MT-201 |
≥515 |
≥275 |
≥30 |
≤100 |
Dimensional Tolerances (ASTM A554)
| Parameter |
Tolerance |
| Outside Dimensions (A & B) |
±0.5% of dimension (min ±0.3mm, max ±1.5mm) |
| Wall Thickness |
±10% |
| Length (fixed) |
+3mm / -0mm |
| Twist |
≤0.5mm per meter × width/100 |
| Concave/Convex |
≤0.4mm per side |
| Corner Radius |
≤1.5 × WT |
| Straightness |
≤1.0mm per meter |
Surface Finishes Available
| Finish |
Code |
Description |
Best For |
| Mill Finish |
– |
As-welded, light scale, dull grey |
Industrial, hidden structural |
| Pickled |
No.1 |
Acid cleaned, matte uniform finish |
Welding prep, industrial |
| Brushed (Hairline) |
No.4 |
150-180 grit, uniform satin lines |
Handrails, furniture, frames |
| Mirror Polished |
No.8 |
Highly reflective, like a mirror |
Decorative, architectural, high-end |
| Satin |
320-400 grit |
Fine matter, non-directional |
Medical, food contact |
ASTM A554 vs. Other Standards
| Standard |
Application |
Construction |
Pressure Rating |
Surface Finish Options |
| ASTM A554 |
Mechanical / Structural |
Welded |
No |
Mill to Mirror |
| ASTM A312 |
Pressure Piping |
Seamless or Welded |
Yes |
Pickled only |
| EN 10219 |
Structural (EU) |
Welded |
No |
Various |
| JIS G3446 |
Mechanical (Japan) |
Welded |
No |
Various |
| GB/T 12770 |
Mechanical (China) |
Welded |
No |
Various |
Key Takeaway: Choose ASTM A554 for mechanical/structural/decorative applications. Choose ASTM A312 for pressure applications (pipes).
Why Choose ASTM A554 Rectangular Tube?
| Advantage |
Benefit |
| Cost Effective |
Lower cost than seamless or ASTM A312 |
| Wide Size Range |
10×5mm to 200×100mm |
| Multiple Finishes |
Mill to mirror — one standard |
| Readily Available |
Common standard, global availability |
| Design Flexibility |
Hundreds of size/wall combinations |
| Easy Fabrication |
Cut, weld, drill, bend easily |
Packaging
| Packaging Type |
Description |
| Standard Export |
Steel strapping + waterproof wrap + wooden crates |
| Hexagonal Bundles |
For small sizes (≤50mm) |
| Square Bundles |
For medium to large sizes |
| Plastic End Caps |
For polished finishes |
| Labeling |
Grade, ASTM A554, size, length, heat number |
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