P275NH is a weldable, fine-grained steel specified in the European standard EN 10028-3. This steel plate is primarily used for manufacturing boilers, pressure vessels, and pipes that transport hot liquids and gases, suitable for moderate to high temperature service.
Chemical Composition
| Elements | P275 NH |
|---|---|
| Ni | 0.50 |
| C | 0.16 |
| Cr | 0.30 |
| Si | 0.40 |
| Mo | 0.08 |
| Mn | 0.80 to 1.50 |
| Cu | 0.30 |
| P | 0.025 |
| Nb | 0.05 |
| S | 0.015 |
| V | 0.05 |
| Al | 0.020 |
| Ti | 0.03 |
| N | 0.012 |
P275NH Standard Pressure Vessel Steel Plate for Extreme Cold Environments
| Thickness | 200°C | 400°C | 50°C | 350°C | 100°C | 300°C | 150°C | 250°C |
|---|---|---|---|---|---|---|---|---|
| over 40(MM) to 60(MM) | 197 | 145 | 247 | 154 | 232 | 166 | 215 | 181 |
| over 150(MM) to 250(MM) | 167 | 122 | 208 | 130 | 196 | 140 | 181 | 153 |
| up to 16(MM) | 213 | 156 | 266 | 166 | 250 | 179 | 232 | 195 |
| over 100(MM) to 150(MM) | 174 | 128 | 218 | 136 | 205 | 147 | 190 | 160 |
| 16(MM) to 40(MM) | 205 | 150 | 256 | 160 | 241 | 173 | 223 | 188 |
| over 60(MM) to 100(MM) | 182 | 133 | 227 | 142 | 214 | 153 | 198 | 167 |
Key Applications
Boiler and Pressure Vessel Manufacturing：As a core material under EN 10028-3 standard, it is mainly used to make boiler drums, high-pressure reactors, heat exchangers and liquid storage tanks. It is suitable for equipment operating in high-temperature environments, ensuring safe operation under pressure and thermal load .
Petrochemical Industry：Widely applied in the production of storage tanks, separators, and pipeline components (flanges, valves) for oil and gas processing. It can resist corrosion from mediums and adapt to harsh working conditions in petrochemical plants .
Power Industry：Used to manufacture key components such as high-pressure water pipes of hydropower stations and thermal power generation equipment. Its excellent high-temperature stability meets the long-term operation needs of power equipment .
Other Fields：Applied in bridge structures, high-rise building frames, and ship hull structures due to high strength. Also used in food industry high-temperature cooking equipment and nuclear reactor pressure shells .
Core Advantages
Excellent High-Temperature Performance：As an elevated temperature quality grade steel, it has enhanced thermal stability compared to ordinary grades. It maintains stable mechanical properties under high-temperature operation, avoiding deformation or failure .
Superior Mechanical Properties：With minimum yield strength ≥275MPa and tensile strength 390-510MPa, it has high strength and hardness. The fine-grain structure (refined by alloy elements) improves toughness and impact resistance .
Good Weldability and Formability：It is a normalized weldable fine-grain steel, easy to perform cold and hot forming and welding processes. No obvious performance degradation after welding, suitable for complex component processing .
High Corrosion Resistance：Properly added nitrogen and other alloy elements enhance its corrosion resistance, which can be used in marine and chemical corrosive environments, extending the service life of equipment .
Reliable Quality and Versatility：Undergoes strict ultrasonic inspection after rolling, with stable quality. It can be customized into plates, bars, pipes and other specifications, meeting diverse industrial needs .
Full specification and details are available on request. The above information is provided for guidance purposes only. For specific design requirements please contact our technical sales staff.
What is P275NH? What is its main material category?
P275NH is a non-alloy pressure vessel steel specified in EN 10028-2 standard. It belongs to the weldable fine-grain structural steel category, mainly used for manufacturing pressure-bearing equipment operating at moderate temperatures.
What are the minimum yield strength and tensile strength of P275NH?
The minimum yield strength of P275NH is 275 MPa (for thickness ≤16mm), and its tensile strength ranges from 410 MPa to 560 MPa. These values ensure good load-bearing capacity in pressure vessel applications.
Which standard specifies the technical requirements for P275NH?
P275NH is governed by the European standard EN 10028-2, which details its chemical composition, mechanical properties, heat treatment, welding requirements, and inspection methods for pressure vessel steels.
What is the recommended heat treatment process for P275NH?
P275NH typically undergoes normalizing heat treatment (heating to 890-950°C, holding adequately, then air cooling). This process refines grains, improves toughness and weldability, meeting pressure vessel service demands.
What is the maximum service temperature of P275NH?
The maximum continuous service temperature of P275NH is around 400°C. Beyond this temperature, its mechanical properties may degrade, affecting the safety and durability of pressure-bearing structures.
What are the main chemical components of P275NH?
Key chemical components (max %) of P275NH: C ≤0.20, Si ≤0.35, Mn ≤1.60, P ≤0.025, S ≤0.015. Trace elements like N, Al may be present to enhance grain refinement.
Is P275NH suitable for welding? What precautions should be taken?
Yes, P275NH has excellent weldability. Precautions: preheat to 80-150°C (based on thickness), control interpass temperature, avoid excessive heat input, and perform post-weld heat treatment if needed for stress relief.
What are the common applications of P275NH?
P275NH is widely used in manufacturing pressure vessels, boilers, storage tanks, heat exchangers, and pipelines for petrochemical, power generation, and chemical industries, suitable for moderate temperature and pressure conditions.
What is the impact test requirement for P275NH?
P275NH requires Charpy V-notch impact tests at -20°C. The minimum average impact energy is 27 J for three specimens, ensuring good low-temperature toughness to resist brittle fracture in cold environments.
What is the thickness range of P275NH plates usually supplied?
P275NH plates are commonly supplied with thickness ranging from 5mm to 200mm. For thicknesses above 16mm, the yield strength may decrease slightly, but it still meets the standard requirements.