What Is a Seamless Stainless Steel TP316LN Tube?
TP316LN Seamless Stainless Steel Tube is supplied for nitrogen-strengthened 316L chemistry for higher yield strength. 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 or ASTM A213 / ASME SA213, subject to 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.
Manufactured via a seamless process (hot piercing + cold drawing/finishing), TP316LN provides:
- Uniform metallurgical structure
- No longitudinal weld seam
- Excellent pressure resistance
- Superior performance under high stress conditions
The designation “LN” indicates:
- L (Low Carbon ≤ 0.035% per ASTM A213/A312) → reduces the risk of sensitization and intergranular corrosion
- N (Nitrogen-enhanced) → increases strength and improves corrosion resistance
This results in a material with higher mechanical strength than TP316L, while maintaining excellent ductility and corrosion resistance.
Key Features & Technical Advantages
High Strength & Increased Design Stress
Nitrogen addition (0.10%–0.16%) raises yield and tensile strength relative to TP316L (minimum 75 ksi [515 MPa] tensile / 30 ksi [205 MPa] yield vs 70 ksi [485 MPa] / 25 ksi [170 MPa]), which can support thinner wall design; the allowable stress actually used for design is that assigned to the grade in the applicable design code.
Excellent Pitting & Crevice Corrosion Resistance
The combination of Molybdenum (Mo) and Nitrogen (N) enhances the PREN value, providing superior resistance in chloride-rich and marine environments.
Intergranular Corrosion Resistance
The low carbon content (≤ 0.035% per ASTM A213/A312) limits chromium carbide precipitation during welding, reducing the risk of sensitization; the actual resistance achieved depends on the welding heat input, cooling rate and the subsequent heat treatment specified for the project.
Excellent Cryogenic Toughness
Maintains outstanding mechanical properties at low temperatures down to -196°C, making it ideal for LNG and cryogenic applications.
High Pressure & Structural Integrity
Manufactured according to:
- ASTM A213
- EN 10216-5
Ensuring reliability in high-pressure and critical service conditions.
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 TP316LN Tube.
Equivalent Grade
| UNS | Common grade name | EN material number | EN steel name | JIS grade | GB/T grade |
|---|---|---|---|---|---|
| S31653 | 316LN | 1.4429 | X2CrNiMoN17-13-3 | SUS316LN | 022Cr17Ni12Mo2N |
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 composition of Stainless Steel 316LN is carefully balanced to achieve its superior strength and corrosion resistance.
| C | Si | Mn | P | S | Cr | Ni | Mo | N |
|---|---|---|---|---|---|---|---|---|
| ≤0.035 | ≤1.00 | ≤2.00 | ≤0.045 | ≤0.030 | 16.00–18.00 | 10.00–13.00 | 2.00–3.00 | 0.10–0.16 |
Data source: ASTM A213-25 / ASME SA213 Table 1, TP316LN row ≤ heat-analysis acceptance limits. Confirm the values against the ordered edition and the MTC.
Stainless Steel 316LN is specifically designed to maintain its strength and shape in high-stress, corrosive environments.
| Tensile Strength | Yield Strength | Elongation | Hardness |
|---|---|---|---|
| ≥ 515 MPa | ≥ 205 MPa | ≥ 35% | ≤ 192 HBW / 200 HV / 90 HRB |
Typical Physical Properties
These physical properties highlight the material’s ability to perform reliably under a wide range of conditions.
| Density | Melting Point | Thermal Expansion | Thermal Conductivity | Modulus of Elasticity | Electrical Resistivity |
|---|---|---|---|---|---|
| 8.0 g/cm³ | 1370 -1400 °C | 16.0 μm/m·°C (20-100°C) | 16.3 W/m·K (20°C) | 193 GPa | 0.74 × 10⁻⁶ Ω·m (20°C) |
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.
Size & Manufacturing Standards
We supply TP316LN seamless tubes in compliance with global standards:
- ASTM A213 / ASME SA213
- EN 10216-5
- ASTM A269
With strict control of:
- Outer diameter (OD) tolerance
- Wall thickness tolerance
- Surface finish and dimensional accuracy
Common Industrial Applications
TP316LN seamless tubes are widely used in high-strength, high-corrosion, and low-temperature environments:
Nuclear & Power Industry
- Heat exchanger tubes
- Control rod systems
- Reactor components
Chemical & Petrochemical
- Urea production systems
- High-pressure reactors
- Acid handling systems
Cryogenic & LNG Systems
- LNG pipelines
- Liquid oxygen / nitrogen systems
- Cryogenic storage tanks
Offshore & Marine Engineering
- Subsea hydraulic lines
- Instrumentation piping
- Seawater systems
Pharmaceutical & Food Industry
- High-purity process piping
- CIP/SIP systems
Advanced Manufacturing Process
- Raw Material Selection & Billet Heating
- Seamless Hot Piercing Forming
- Cold Drawing / Cold Rolling for Precision
- Solution Annealing Heat Treatment
- Full Non-Destructive Testing (NDT):
- Ultrasonic Testing (UT)
- Eddy Current Testing (ET)
- Hydrostatic Testing
100% Quality Assurance & Certification
We ensure full compliance with international standards:
- EN 10204 3.1 Material Test Certificates (MTC) as standard; 3.2 on arrangement
- 100% PMI (Positive Material Identification)
- Mechanical & Chemical Testing
Frequently Asked Questions
What sizes are available for TP316LN seamless tube?
The overall range is OD 6–257 mm; WT 0.5–35 mm. Requirements outside this range are reviewed against mill capability on request.
Which specification governs TP316LN seamless tube?
ASTM A269 or ASTM A213 / ASME SA213, subject to service is the governing specification for TP316LN seamless tube. The edition in force at order time is stated on the quotation and purchase order; chemistry, mechanical properties, heat treatment, dimensions and testing are reported against the ordered standard and material heat.
What inspection documents are provided?
Each order is documented with a mill test certificate stating heat chemistry and mechanical test results. EN 10204 3.1 certification, hydrostatic testing, eddy-current or ultrasonic inspection and PMI are performed when specified in the purchase order.
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 TP316LN 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.
