Seamless Stainless Steel TP309 Pipe
Distinguished by its high Chromium (23%) and Nickel (13%) content, our TP309 tubing provides exceptional resistance to scaling and carburizing atmospheres at continuous service temperatures up to 980°C (1800°F). These pipes are indispensable for mission-critical applications in boiler baffles, furnace components, and high-temperature chemical processing units. Through advanced cold-drawing and precise solution annealing, GZH ensures every pipe maintains a uniform microstructure and optimized creep strength, offering superior durability under intense thermal stress.
“For applications requiring lower carbon content to improve weldability and prevent carbide precipitation, we also offer TP309S (UNS S30908).”
What is a Seamless Stainless Steel TP309 Pipe?
Seamless Stainless Steel TP309 Pipe is a cylindrical tube crafted from a single, solid piece of stainless steel. Like other seamless pipes, it lacks a weld joint, ensuring structural integrity and a uniform grain structure.
The"309"in its name signifies an austenitic stainless steel that is richer in chromium and nickel than the more common 304 grade. This enhanced composition is what gives it its primary advantage: superior performance at elevated temperatures. It is an ideal material for applications that require resistance to oxidation and scaling under intense heat.
Key Features and Advantages
Seamless TP309 Stainless Steel Pipe offer several significant benefits that make them invaluable in specific industries:
Exceptional High-Temperature Resistance: With its high chromium and nickel content, 309 stainless steel performs excellently in temperatures up to 1038°C (1900°F). It is highly resistant to oxidation and scaling, maintaining its structural integrity and performance even under prolonged heat exposure.
Strong Corrosion Resistance: While primarily known for its heat resistance, Grade 309 also provides good corrosion resistance, making it suitable for environments with both high temperatures and corrosive agents.
High Pressure Tolerance: The seamless construction eliminates a potential weak point, allowing the pipe to safely handle high internal pressures.
Durable and Reliable: The uniform, seamless structure ensures maximum strength and durability, leading to a longer service life and lower maintenance costs.
Product Specifications and Data
To provide a comprehensive overview of this material, here are the detailed technical specifications and performance data for 309 stainless steel.
Table 1: Chemical Composition of Stainless Steel 309
The composition of Stainless Steel 309 is carefully balanced to achieve its superior high-temperature oxidation resistance and strength.
| Cr | Ni | Mn | Si | P | S | Fe | C |
| 22.00 - 24.00 | 12.00 - 15.00 | ≤ 2.00 | ≤ 1.50 | ≤ 0.045 | ≤ 0.030 | Bal | ≤ 0.20 |
Table 2: Typical Mechanical Properties of Stainless Steel 309
Stainless Steel 309 is specifically designed to maintain its strength and shape in high-stress, high-temperature environments.
| Property | Value (Annealed) |
| Tensile Strength | ≥ 515 MPa |
| Yield Strength | ≥ 205 MPa |
| Elongation | ≥ 30% |
| Hardness | ≤ 217 HBW |
Table 3: Typical Physical Properties of Stainless Steel 309
These physical properties highlight the material's ability to perform reliably under a wide range of conditions.
| Property | Value |
| Density | 7.9 g/cm³ |
| Melting Point | 1400 - 1450 °C approx. |
| Thermal Expansion | 16.5 µm/m·°C (20-100°C) |
| Thermal Conductivity | 14.2 W/m·K (20°C) |
| Modulus of Elasticity | 200 GPa |
| Electrical Resistivity | 0.78 x 10⁻⁶ Ω·m (20°C) |
Table 4: 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 OF seamless Stainless steel TP309 pipe
The unique combination of heat and corrosion resistance makes 309 stainless steel seamless pipes a preferred choice for:
Furnace Components: Used for furnace linings, heat shields, and components in high-temperature ovens.
Heat Exchangers: For transferring heat in industrial processes where extreme temperatures are present.
Kiln Linings and Parts: Components for cement kilns and other high-temperature processing equipment.
Automotive Exhaust Systems: Used in parts that are subjected to high heat and corrosive gases.
Manufacturing Process Of Seamless Stainless Steel TP309 Pipe
The manufacturing of a TP309 Seamless Stainless Steel 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 309 seamless pipe meets the highest standards for performance and reliability in the most demanding applications.
