Overview
Seamless Austenitic Steel 310H Pipe is a high-temperature austenitic alloy, specifically developed for prolonged service in elevated-temperature environments. With a composition of 25% chromium, 20% nickel, and a higher carbon content (0.04-0.10%) than standard TP310 (S31000), this grade (H denoting "high carbon") offers improved creep and stress-rupture strength at high temperatures. It complies with standards such as ASTM A312 and ASME SA-312, making it ideal for critical applications where thermal stability and resistance to oxidation are paramount.
The seamless construction ensures uniform microstructure and minimal defects, enhancing its ability to withstand cyclic thermal loading and high-pressure conditions without failure. TP310H is frequently used in applications requiring long-term exposure to temperatures up to 1150°C, where lower-alloyed steels would succumb to oxidation or creep.
Mechanical Properties
Grade
| 310
| 310S
| 310H
|
Tensile Strength
| ≥515Mpa
| ≥515Mpa
| ≥485Mpa
|
Yield strength
| ≥205Mpa
| ≥205Mpa
| ≥170Mpa
|
Elongation %
| ≥35
| ≥35
| ≥35
|
Hardness
| ≤90 HRB
| ≤90 HRB
| ≤90 HRB |
| Grade | C | Mn | P | S | Si | Cr | Mo | Ni |
| TP310 | ≤0.25
| ≤2.00
| ≤0.045
| ≤0.03
| ≤1.50
| 24.00-26.00 | / | 19.00-22.00 |
| TP310S | ≤0.08
| ≤2.00
| ≤0.045
| ≤0.03
| ≤1.00
| 24.00-26.00
| ≤0.75 | 19.00-22.00
|
| TP310H | 0.04-0.10 | ≤2.00
| ≤0.045
| ≤0.03
| ≤0.75
| 24.00-26.00
| / | 19.00-22.00
|
Features
Extreme High-Temperature Resistance: Exhibits excellent oxidation resistance up to 1200°C in continuous service and 1300°C in intermittent use, thanks to its high chromium and nickel content forming a protective oxide layer.
Creep & Stress-Rupture Strength: The higher carbon content precipitates carbides, strengthening the matrix and delaying deformation at elevated temperatures compared to low-carbon TP310.
Corrosion Resistance: Resistant to many organic and inorganic acids, as well as intergranular corrosion when properly heat-treated, though it is not recommended for highly reducing or chloride-rich environments.
Good Fabricability: Can be welded using GTAW or GMAW with matching filler metals (e.g., ER310), though post-weld heat treatment may be required for certain applications to optimize ductility.
Application
Petroleum Refining: Used in ethylene crackers, reformer tubes, and furnace coils where temperatures exceed 1000°C, resisting coking and scale formation.
Power Generation: Ideal for superheater tubes in utility boilers, especially for advanced ultra-supercritical power plants operating at extreme temperatures and pressures.
Industrial Furnaces: Employed in radiant tubes, muffles, and retorts for heat treatment furnaces, cement kilns, and incinerators exposed to harsh thermal cycles.
Aerospace & Automotive: Used in exhaust manifolds and turbocharger components for high-performance engines, where resistance to thermal fatigue and oxidation is critical.
