What Is a Seamless Stainless Steel TP304 Tube?
TP304 Seamless Stainless Steel Tube is supplied for general-purpose corrosion resistance and reliable fabrication. The size range shown (OD 6–257 mm; WT 0.5–35 mm) is the overall capability across this product family, not a per-grade commitment. Confirm the specific OD × WT × length combination for the ordered grade in the quotation. The governing specification must be stated on the purchase order: ASTM A269; ASTM A213 / ASME SA213 when ordered for heat-exchanger or boiler service. Chemistry, mechanical properties, heat treatment, dimensional tolerance, NDT and certification must be reported against the ordered standard and material heat; do not treat typical values as guaranteed acceptance limits.
As the industry-standard”18/8″austenitic grade, Type 304 is the most versatile alloy for tubing. It offers a strategic balance of high ductility, excellent oxidation resistance, and long-term cost-efficiency in diverse industrial environments.
Key Technical Advantages
While standard piping focuses on fluid volume, TP304 seamless tubing is defined by its rigorous dimensional control and structural integrity:
- Tight Dimensional Tolerances: Through precision cold-drawing (CD) or cold-rolling, these tubes achieve superior accuracy in Outside Diameter (OD) and Wall Thickness (WT), essential for high-tolerance fittings.
- Enhanced Surface Integrity: The manufacturing process results in a superior surface finish (often reaching Ra ≤ 0.8μm or better), minimizing turbulence in fluid flow and preventing bio-fouling in sensitive applications.
- Superior Pressure Rating: The absence of a weld seam allows for higher working pressures and safety factors, making them indispensable for critical hydraulic and instrumentation systems.
- Excellent Formability: The inherent ductility of the 304 grade allows for complex fabrication, including coiling, 180° bending, and flaring, without compromising the material’s microstructural stability.
Product Specifications and Data
To provide a comprehensive overview of this high-performance material, here are the detailed technical specifications and performance data for Seamless Stainless Steel TP304 Tube.
Equivalent Grade
| UNS | Common grade name | EN material number | EN steel name | JIS grade | GB/T grade |
|---|---|---|---|---|---|
| S30400 | 304 | 1.4301 | X5CrNi18-10 | SUS304 | 06Cr19Ni10 / 0Cr18Ni9 |
Grade correspondence does not make ASTM, ASME, EN, JIS and GB delivery requirements interchangeable. Confirm chemistry, heat treatment, mechanical properties, dimensions, testing and certification against the purchase specification. Approximate or unconfirmed correspondences retain their qualification. See the grade designation index.
Chemical Composition
The superior properties of TP304 stainless steel are a direct result of its precisely controlled chemical composition. Below are the typical elemental content ranges for this grade:
| Grade | C | Si | Mn | Cr | Ni | S | P |
|---|---|---|---|---|---|---|---|
| 304 | ≤ 0.08 | ≤1.00 | ≤2.00 | 18.00- 20.00 | 8.00- 11.00 | ≤0.03 | ≤0.045 |
| 304L | ≤0.035 | ≤1.00 | ≤2.00 | 18.00- 20.00 | 8.00- 12.00 | ≤0.03 | ≤0.045 |
| 304H | 0.04- 0.10 | ≤1.00 | ≤2.00 | 18.00- 20.00 | 8.00- 11.00 | ≤0.03 | ≤0.045 |
Data source: ASTM A213-25 / ASME SA213 Table 1, TP304 row ≤ heat-analysis acceptance limits. Confirm the values against the ordered edition and the MTC.
Typical Mechanical Properties
Mechanical properties are key indicators of how a material behaves under various forces. These figures directly relate to the strength, ductility, and overall resilience of TP304 seamless tubes.
| Material | Tensile Strength ksi(MPa) | Yield Strength ksi(MPa) | Elongation (%) | Hardness Brinell/Vickers | Hardness Rockwell |
|---|---|---|---|---|---|
| 304 | ≥75(515) | ≥30(205) | ≥ 35 | ≤192HBW/200HV | ≤90HRB |
| 304L | ≥70(485) | ≥25(170) | ≥ 35 | ≤192HBW/200HV | ≤90HRB |
| 304H | ≥75(515) | ≥30(205) | ≥ 35 | ≤192HBW/200HV | ≤90HRB |
Note: Typical values for reference only — not acceptance limits. Mechanical properties are reported on the MTC against the ordered standard, product form, condition and test temperature.
Typical Physical Properties
Physical properties dictate a material’s inherent characteristics under different environmental conditions, such as density, melting point, and thermal conductivity.
| Density | 8.0 g/cm³ |
|---|---|
| Melting Point | 1400-1450 °C |
| Thermal Expansion | 17.2 μm/m·°C |
| Thermal Conductivity | 16.2 W/m·K |
| Modulus of Elasticity | 193 GPa |
| Electrical Resistivity | 0.72 × 10⁻⁶ Ω·m |
Note: Typical values for reference only — not acceptance limits. Physical and mechanical properties are reported on the MTC against the ordered standard, product form and condition.
ASTM A1016/A1016M Tube Size Tolerance Chart
Size Tolerance Chart (mm)
| Specified Outside Diameter (OD) (Inches) | Permissible Variations in OD (± Inches) |
|---|---|
| 1⁄2 to 1 | ±0.005 |
| Over 1 to 1-1⁄2 | ±0.008 |
| Over 1-1⁄2 to 2 | ±0.010 |
| Over 2 to 2-1⁄2 | ±0.012 |
| Over 2-1⁄2 to 3-1⁄2 | ±0.014 |
| Over 3-1⁄2 to 5 | ±0.020 |
Tolerance basis: permitted variations per the governing specification stated on this page and the applicable general-requirements standard (ASTM A1016 / ASME SA1016) for the ordered product form; the wall-thickness and length variations in this section follow the same basis.
| Specified Outside Diameter (OD) (Inches) | Specified Wall Thickness (WT) (Inches) | Permissible Variation (± Inches) |
|---|---|---|
| 1⁄2 to 1 (Inclusive) | 0.025 to 0.065(Inclusive) | ±0.010 |
| Over 0.065to 0.134 (Inclusive) | ±0.012 | |
| Over 1 to 1-1⁄2 (Inclusive) | 0.025 to 0.065 (Inclusive) | ±0.010 |
| Over 0.065 to 0.134 (Inclusive) | ±0.012 | |
| Over 1-1⁄2 to 2 (Inclusive) | 0.025 to 0.049 (Inclusive) | ±0.011 |
| Over 0.049 to 0.083 (Inclusive) | ±0.012 | |
| Over 0.083 to 0.148 (Inclusive) | ±0.014 | |
| Over 2 to 2-1⁄2 (Inclusive) | 0.032 to 0.065 (Inclusive) | ±0.013 |
| Over 0.065 to 0.109 (Inclusive) | ±0.015 | |
| Over 0.109 to 0.165 (Inclusive) | ±0.017 | |
| Over 2-1⁄2 to 3-1⁄2 (Inclusive) | 0.032 to 0.165 (Inclusive) | ±0.020 |
| Over 0.165 to 0.220 (Inclusive) | ±0.025 | |
| Over 3-1⁄2 to 5 (Inclusive) | 0.083 to 0.165 (Inclusive) | ±0.025 |
| Over 0.165 to 0.220 (Inclusive) | ±0.030 |
Length Tolerance
- For Specific Cut Lengths, the standard tolerance is +1⁄8 in. [3 mm], -0 in. [0 mm].
Important Note: The values presented here are based on the dimensional tolerance tables in ASTM A1016/A1016M (General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless Steel Tubes), contains other essential requirements like straightness and details for tubes with ODs outside of this range. Always consult the latest official standard for design and procurement.
Strategic Industrial Applications
The reliability of SS 304 seamless tubes makes them a primary choice for critical infrastructure
Heat Transfer Equipment
Ideal for heat exchangers, condensers, and evaporators where thermal conductivity and resistance to pitting are required.
Instrumentation & Control
High-precision small-bore tubing for hydraulic control lines, pneumatic systems, and subsea umbilical applications.
High-Purity Systems
Used extensively in the food, beverage, and dairy industries where smooth internal surfaces are mandatory for CIP (Clean-in-Place) sterilization.
Precision Engineering
Critical components for the aerospace and automotive sectors, specifically for fuel injection systems and structural hydraulic frames.
100% Certified Testing & Documentation
- EN 10204 3.1 Material Test Certificate (MTC) as standard; EN 10204 3.2 on arrangement
- Raw Materials Certificate
- 100% PMI (Positive Material Identification)
- Heat Treatment Charts
- Third-Party Inspection Report
- Surface roughness and size measurement
- Manufacturer Test Certificate (Impact Testing, Flattening, Flare, Bend, Hardness, Intergranular, Pitting Corrosion, Grain size, ET, UT, HT)
- Laboratory Test Certificate from the Government-Approved Lab
Frequently Asked Questions
What sizes are available for TP304 seamless tube?
Which specification governs TP304 seamless tube?
What inspection documents are provided?
Technical review: page data reviewed by the Xinzhe technical desk on 2026-09-27. Chemistry acceptance limits are compiled from the governing ASTM/ASME specification stated on this page; mechanical and physical values are typical reference data and are not acceptance guarantees. Values must be confirmed against the standard edition in force at order time and the material test certificate.
Ready to Request a Quotation?
Send the size (OD and wall or schedule), quantity, length, end finish and the inspection items you need as acceptance criteria — you will get a written quotation stating the specification and edition, delivery condition, documents included and lead time.
For the same grade in pipe form, see the TP304 seamless pipe. To compare other grades and size combinations, browse the Stainless Steel Seamless Pipe category. Minimum order quantity and lead time are confirmed on enquiry against the ordered grade, size and quantity.
