What Is a Seamless Stainless Steel TP304L Tube?
TP304L Seamless Stainless Steel Tube is supplied for low-carbon weldability and reduced sensitization risk. 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.
Unlike welded tube, seamless TP304L tubing has no longitudinal weld seam, which supports structural integrity and pressure design in demanding industrial environments; allowable pressure is calculated from the governing design code.
Because of its low carbon composition and excellent corrosion resistance,TP304L seamless stainless steel tube is widely used in industries such as oil & gas, chemical processing, pharmaceutical production, food processing, and aerospace engineering.
Common manufacturing standards include:
- ASTM A213 TP304L Seamless Tube – for boilers and heat exchangers
- ASTM A269 TP304L Seamless Tube – for general service and instrumentation
- ASTM A312 TP304L Pipe – for industrial piping systems
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 TP304L Tube.
Equivalent Grade
| UNS | Common grade name | EN material number | EN steel name | JIS grade | GB/T grade |
|---|---|---|---|---|---|
| S30403 | 304L | 1.4307 | X2CrNi18-9 | SUS304L | 022Cr19Ni10 / 00Cr19Ni10 |
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
| 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, TP304L row ≤ heat-analysis acceptance limits. Confirm the values against the ordered edition and the MTC.
Typical Mechanical Properties
| 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
| 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.
The Standard of ASTM A789 Size Tolerance Size 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 common tables in the ASTM A789 standard. The full specification, particularly the referenced 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.
Common Industrial Applications
Due to its excellent corrosion resistance, weldability, and mechanical strength,TP304L seamless tubing is widely used in critical industries.
Pharmaceutical & Biotechnology
TP304L tubes are used in sterile fluid transfer systems, medical tubing, and hypodermic needle manufacturing where hygiene and chemical stability are essential.
Oil & Gas Industry
In upstream and downstream operations, seamless TP304L tubing is used for:
- Instrumentation tubing
- Control lines
- Heat exchanger tubing
- Corrosion-resistant piping systems
Chemical Processing Plants
TP304L tubes are suitable for handling corrosive fluids, solvents, and chemical reagents in process equipment.
Food & Beverage Processing
Because stainless steel TP304L meets strict sanitary and hygiene standards, it is commonly used in:
- Dairy processing lines
- Beverage production systems
- Food manufacturing equipment
Aerospace & Precision Engineering
In aerospace and high-precision manufacturing, TP304L seamless tubing is used for:
- Hydraulic systems
- Fuel delivery lines
- Pressure sensors
- Flow measurement equipment
Why Choose TP304L Stainless Steel Tubing?
The “L” in TP304L stands for Low Carbon, which provides important advantages during welding and fabrication.
Low Carbon Composition
TP304L contains maximum 0.03% carbon, compared to 0.08% in standard 304 stainless steel.
This significantly reduces the risk of chromium carbide precipitation, also known as sensitization, during welding.
Improved Corrosion Resistance After Welding
Because carbide precipitation is limited, TP304L stainless steel tubes retain better corrosion resistance in the heat-affected zone (HAZ).
This reduces the need for post-weld annealing in many applications; whether it is required is governed by the project specification and the welding procedure.
Excellent Weldability
TP304L seamless tubes are ideal for systems requiring extensive welding, such as piping networks, instrumentation lines, and sanitary process systems.
Key Technical Advantages of Seamless TP304L Tubing
| Feature | Industrial Benefit |
|---|---|
| Seamless Construction | No weld seam means higher burst pressure and improved reliability |
| Resistance to Intergranular Corrosion | Ideal for welded components used in corrosive environments |
| High Dimensional Precision | Tight tolerances on outside diameter (OD) and wall thickness (WT) |
| Cryogenic Strength | Excellent toughness at extremely low temperatures |
| Smooth Internal Surface | Reduces fluid friction and prevents bacterial buildup |
Because of these properties, TP304L seamless stainless steel tubes are widely chosen for high-purity and high-pressure applications.
TP304L Stainless Steel Tube Quality Assurance and Testing
Testing and certification are carried out to the scope agreed on the purchase order. The following documents are available.
Certification and Documentation
- EN 10204 3.1 Material Test Certificates as standard; 3.2 by arrangement
- Raw material heat number traceability
- Third-party inspection reports (TPI), when specified
- PMI – Positive Material Identification, when specified
Non-Destructive Testing (NDT)
- Eddy Current Testing (ET)
- Ultrasonic Testing (UT)
- Hydrostatic Testing (HT)
Mechanical and Metallurgical Testing
- Tensile testing
- Hardness testing
- Flattening and flaring tests
- Bend testing
- Intergranular corrosion (IGC) testing
- Grain size and microstructure analysis
Dimensional & Surface Inspection
- Precision OD / ID measurement
- Wall thickness inspection
- Surface roughness testing (Ra)
These inspections help confirm that TP304L stainless steel seamless tubing meets ASTM and international quality standards.
TP304 vs TP304L Stainless Steel Tube
| Property | TP304 | TP304L |
|---|---|---|
| Carbon Content | Max 0.08% | Max 0.03% |
| Corrosion Resistance | Excellent | Superior after welding |
| Strength | Slightly higher | Slightly lower |
| Post-Weld Heat Treatment | Often required | Usually not required |
Because of its better weldability and corrosion resistance,TP304L stainless steel tubing is generally preferred in fabricated piping systems and welded structures.
Frequently Asked Questions
What is the difference between TP304 and TP304L?
TP304L contains lower carbon content, which limits carbide precipitation during welding and improves corrosion resistance in the heat-affected zone.
What standards apply to TP304L seamless tubes?
The most common standards are ASTM A213, ASTM A269, and ASTM A312 .
Is TP304L suitable for high-pressure applications?
Yes. Because of its seamless construction , TP304L tubing offers higher pressure resistance compared to welded tubes .
What industries commonly use TP304L tubes?
Major industries include oil & gas, chemical processing, pharmaceuticals, food processing, and aerospace .
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 TP304L 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.
