Seamless Stainless steel TP316LN pipe
Distinguished by the strategic addition of Nitrogen (0.10–0.16%), our TP316LN piping offers significantly higher yield strength than standard 316L while maintaining excellent ductility and non-magnetic characteristics even after cold working. These pipes are indispensable for mission-critical applications in high-pressure chemical reactors, nuclear engineering, and cryogenic processing. Through advanced cold-drawing and precise solution annealing, GZH ensures every pipe maintains a stable austenitic microstructure and optimized resistance to sensitization and pitting.
“TP316LN offers a minimum yield strength of 205 MPa, which is higher than the 170 MPa of standard TP316L.”
What is a Seamless Stainless steel TP316LN pipe?
Seamless Stainless steel TP316LN pipe is a cylindrical tube crafted from a single, solid billet of stainless steel. Like other seamless products, it has no weld joint, ensuring maximum structural integrity and high-pressure ratings.
The"316LN"designation signifies an austenitic stainless steel that is a low-carbon ("L") version of 316, with an added amount of nitrogen ("N"). The nitrogen addition provides a significant boost to the material's mechanical properties, particularly its yield strength and tensile strength. It also enhances the material's resistance to pitting and crevice corrosion, making it even more robust in highly corrosive environments. This combination of properties makes 316LN an excellent choice for a variety of critical applications.
Key Features and Advantages
TP316LN Seamless Stainless Steel Pipe offer a unique combination of benefits that make them invaluable in demanding applications:
Superior Strength: The nitrogen addition provides a significant boost to the material's strength, allowing for a thinner wall design without compromising performance. This can lead to lighter components and reduced material costs.
Enhanced Corrosion Resistance: Nitrogen enhances resistance to pitting and crevice corrosion, especially in chloride-rich environments. It works in synergy with molybdenum to make the material even more effective than standard 316L.
Excellent Weldability: As a low-carbon grade, it is highly resistant to sensitization and intergranular corrosion after welding. The nitrogen also helps stabilize the material, maintaining its properties in the weld zone.
High Pressure Tolerance: The seamless construction provides a uniform, robust structure that safely handles high internal pressures, which is critical in fluid transport.
Product Specifications and Data
To provide a comprehensive overview of this high-performance material, here are the detailed technical specifications and performance data for 316LN stainless steel.
Table 1: Chemical Composition of Stainless Steel 316LN
The composition of Stainless Steel 316LN is carefully balanced to achieve its superior strength and corrosion resistance.
| Cr | Ni | Mo | N | P | S | Mn | Si | C |
| 16.50 - 18.50 | 10.00−14.00 | 2.00−3.00 | 0.10 - 0.16 | ≤0.045 | ≤0.03 | ≤2.00 | ≤0.75 | ≤0.03 |
Table 2: Typical Mechanical Properties of Stainless Steel 316LN
Stainless Steel 316LN is specifically designed to maintain its strength and shape in high-stress, corrosive environments.
| Property | Value (Annealed) |
| Tensile Strength | ≥ 585 MPa |
| Yield Strength | ≥ 290 MPa |
| Elongation | ≥ 35% |
| Hardness | ≤ 217 HBW |
| Brinell Hardness | ≤217 HB |
Table 3: Typical Physical Properties of Stainless Steel 316LN
These physical properties highlight the material's ability to perform reliably under a wide range of conditions.
| Property | Value |
| Density | 8.0 g/cm³ |
| Melting Point | 1370 - 1400 °C |
| Thermal Expansion | 16.0 µm/m·°C (20-100°C) |
| Thermal Conductivity | 16.3 W/m·K (20°C) |
| Modulus of Elasticity | 193 GPa |
| Electrical Resistivity | 0.74 x 10⁻⁶ Ω·m (20°C) |
Table4:The Standard of Stainless Steel Seamless Pipe Size Tolerance Size Chart :
| Standard | OD(D) | Tolerance（MM) | Thickness(S) | Tolerance(MM) | Length | Tolerance | |
| MM | Common | High | MM | MM | |||
| ASTM A312 | D≤48.3 | +0.4/-0.8 | 10.3 | +20%-12.5% | +6.0/0 | ||
| 48.3 | ±0.8 | 88.9 | +22.5%/-12.5% | ||||
| 114.3 | +1.6/-0.8 | 88.9 | +15%/-12.5% | ||||
| 219.1 | +2.4/-0.8 | D≥508, t/D≤5%,SMLS | +22.5%/-12.5% | ||||
| 457.2 | +3.2/-0.8 | D≥508, t/D>5%,SMLS | +15%/-12.5% | ||||
| 660.4 | +4.0/-0.8 | D≥508, WELD | +17.5%/-12.5% | ||||
| 863.6 | +4.8/-0.8 | ||||||
| JIS 3459 Hot-Finished Smls Pipe | D＜50 | ±0.51 | S＜4 | ±0.5 | |||
| D≥50 | ±1.0% | S≥4 | ±12.5% | ||||
| JIS 3459 Cold-Finished | D＜30 | ±0.3 | S＜2 | ±0.2 | |||
| D≥30 | ±1.0% | S≥2 | ±10.0% | ||||
| JIS G3463 Hot-Finished Smls Pipe | 100 | +0.4/-0.8 | D＜100，S<2 | / | D<50, L<7M | +7/0 | |
| D＜100，2≤S<2.4 | +40%/0 | D<50,7< L<10M | +10/0 | ||||
| D＜100，2.4≤S<3.8 | +35%/0 | ||||||
| D＜100，3.8≤S<4.6 | +33%/0 | ||||||
| D＜100，4.6≤S | +28%/0 | D<50,10< L<13M | +13/0 | ||||
| 100≤D<120 | +0.4/-1.2 | D>100, S＜2 | / | ||||
| 120≤D<160 | D>100，2≤S<2.4 | / | D<50,13M< L | +15/0 | |||
| 160≤D<200 | +0.4/-1.8 | D>100，2.4≤S<3.8 | +35%/0 | ||||
| 200≤D | +0.4/-2.4 | D>100，3.8≤S<4.6 | +33%/0 | D>50,7< L<7M | +10/0 | ||
| D>100，4.6≤S | +28%/0 | ||||||
| JIS G3463 Cold-finished | <60 | +0.4/-0.8 | D<40, S<2.0 | +0.4/0 | |||
| 60≤D<80 | ±0.3 | D<40, S≥2.0 | +20%/0 | D>50,7< L<10M | +13/0 | ||
| 80≤D<100 | ±0.4 | D≥40 | +22%/0 | ||||
| 100≤D<120 | +0.4/-0.6 | ||||||
| 120≤D<160 | +0.4/-0.8 | D>50,10M< L | +15/0 | ||||
| 160≤D<200 | +0.4/-1.2 | ||||||
| 200≤D | +0.4/-1.6 | ||||||
| GB/T 14975 冷拔(扎)钢管 | D<12.7 | ±0.3 | ±0.1 | 所有壁厚，普通级PA | +12.5%/-10% | ||
| 12.7 | ±0.15 | ||||||
| 38.1 | ±0.4 | ±0.3 | |||||
| 88.9 | ±0.9% | ±0.4 | |||||
| 139.7 | ±0.8 | 所有壁厚，高级PC | ±10% | ||||
| 203.2 | ±1.1 | ||||||
| 219.1 | ±1.6 | ||||||
| D≥323.9 | ±0.5% | ||||||
| GB/T 14976 冷拔(轧)钢管 | 6 | ±0.2 | ±0.15 | S≤3 | ±12%(10% /0高级PC) | ||
| 10≤D<30 | ±0.2 | ±0.2 | |||||
| 30≤D<50 | ±0.2 | ±0.3 | S>3 | +12.5%/-10%(10%/0高级PC) | |||
| 50≤D<219 | 0.85% | 0.75% | |||||
| D>219 | 0.9% | 0.8% | Smin, all | +22%/0(+20%/0高级PC) | |||
Common Applications
The combination of superior strength, corrosion resistance, and excellent weldability makes Seamless TP316LN Stainless Steel Pipe a preferred choice for:
Chemical and Petrochemical: For piping and components that require high strength and resistance to corrosive media, such as tanks and vessels.
Pressure Vessels: Ideal for high-pressure systems where a robust and reliable material is essential.
Cryogenic Applications: Its excellent toughness and stability at extremely low temperatures make it suitable for cryogenic equipment.
Offshore and Marine: Used in components for offshore platforms and other marine applications exposed to saltwater.
Manufacturing Process
The manufacturing of a Seamless Stainless steel TP316LN pipe is a precise, multi-step process:
Heating: A solid steel billet is heated to a high temperature.
Piercing: A piercing mill pushes a mandrel through the center of the heated billet to form a hollow shell.
Rolling and Sizing: The hollow shell is then rolled and drawn to reduce its diameter and wall thickness to the desired dimensions.
Finishing: The pipe is cut to length, heat-treated, and subjected to finishing processes like pickling to achieve its final state.
This meticulous process ensures that every 316LN seamless pipe meets the highest standards for performance and reliability in the most demanding applications.
