Steel P275NH N-70-100
Heat-treated state
EN P275NH
Heavy sections for nozzles and tubesheets; 225 MPa minimum yield.
Values for the N-70-100 condition
Other P275NH tempers and conditions
P275NH is listed in 8 conditions; see the grade overview at P275NH.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
N | Maximum thickness range of the standard; lowest guaranteed strength level. | 230 | 405 | 26 | 122 HB | 10.5 % IACS |
N | Very heavy plate; 215 MPa min yield, toughness verified at mid-thickness. | 240 | 410 | 27 | 124 HB | 10.5 % IACS |
N-70-100This page N | Heavy sections for nozzles and tubesheets; 225 MPa minimum yield. | 250 | 420 | 28 | 126 HB | 10.5 % IACS |
N | Thick plate for large tanks; yield 235 MPa min and lower tensile band. | 260 | 425 | 28 | 128 HB | 10.5 % IACS |
N | Heavier vessel shells; minimum yield 255 MPa, tensile band unchanged. | 280 | 440 | 29 | 132 HB | 10.5 % IACS |
N | Medium-thickness plate; yield drops one step to 265 MPa minimum. | 290 | 445 | 29 | 133 HB | 10.5 % IACS |
Normalized then stress relieved / simulated PWHT | Choose when the fabricated vessel will see PWHT; slightly lower strength but improved dimensional stability and residual-stress state. | 290 | 440 | 31 | 130 HB | 10.5 % IACS |
NDefault Normalized | Standard stocked delivery condition for thin pressure-vessel plate with full 275 MPa yield. | 300 | 450 | 30 | 135 HB | 10.5 % IACS |
What is P275NH N-70-100?
P275NH N-70-100 is P275NH heat treated to N-70-100 — heavy sections for nozzles and tubesheets; 225 MPa minimum yield. P275NH N-70-100 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 94% of steel grades. Elongation at break is 28% and the elastic modulus is 210 GPa (30.5 Msi). P275NH N-70-100 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,490°C (2,714 °F). N is the default condition FabDigit quotes; N-70-100 is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 28%, better than 89% of steel grades
- High electrical conductivity — 10.5 % IACS, better than 89% of steel grades
- Conducts heat well — 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades
- Readily welded — 88/100, better than 87% of steel grades
- Forms and bends easily — 68/100, better than 83% of steel grades
Limitations
- Low strength — 250 MPa (36.3 ksi), worse than 94% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
P275NH N-70-100 properties
Typical room-temperature values for P275NH N-70-100; 22 are specific to this condition. Other listed values are P275NH reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
P275NH N-70-100 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,490°C (2,714 °F).
Mechanical16
P275NH N-70-100 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 94% of steel grades. Elongation at break is 28% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
P275NH N-70-100 is rated for continuous service to 400°C (752 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
P275NH N-70-100 conducts electricity at 10.5 % IACS, better than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of P275NH N-70-100 takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability8
P275NH N-70-100's machinability is good (61/100, better than 87% of steel grades); weldability excellent (88/100); formability good (68/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with P275NH N-70-100
Is P275NH easy to machine?
Machines like normalized C-Mn steel (~65 % of AISI 1212); use sharp positive-rake carbide, moderate speeds, and expect gummy chips at low S levels.
Can P275NH be welded?
Excellent weldability with CEV typically ≤ 0.40; SAW/SMAW/GMAW with low-hydrogen consumables, preheat 50–100 °C for thick sections, PWHT 550–620 °C when required by EN 13445 / PED.
Can P275NH be formed, bent or molded?
Cold rollable into shells with generous bend radii (≥ 2t for t ≤ 20 mm); hot forming 850–1000 °C followed by re-normalizing to restore fine-grain properties.
What surface finishes work on P275NH?
No anodizing; shot-blast to Sa 2½ then epoxy/zinc-rich primer, hot-dip galvanize or weld-overlay clad for corrosive duty.
P275NH chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cladle analysis, t ≤ 150 mm | ≤ 0.18 | 0.14 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.5 – 1.4 | 1.1 |
| P | ≤ 0.03 | 0.01 |
| S | ≤ 0.01 | 0 |
| Altotal Al, grain refinement | ≥ 0.02 | 0.04 |
| N | ≤ 0.01 | 0.01 |
| Cr | ≤ 0.3 | 0.05 |
| Cu | ≤ 0.3 | 0.08 |
| Ni | ≤ 0.5 | 0.1 |
| Mo | ≤ 0.08 | 0.02 |
| Nb | ≤ 0.05 | 0.02 |
| Ti | ≤ 0.03 | 0.01 |
| VNb+Ti+V ≤ 0.05 combined | ≤ 0.05 | 0.01 |
| Fe | balance | — |
P275NH N-70-100 — frequently asked
What is P275NH N-70-100 used for?
P275NH N-70-100 is typically used for pressure vessels, pipeline components, heat exchangers and boiler parts. In short: workhorse EN vessel plate; weldable at CEV ≤ 0.40; A516 Grade 60 counterpart.
What is the yield strength of P275NH N-70-100?
P275NH N-70-100 has a typical yield strength of 250 MPa (36.3 ksi) and a tensile strength of 420 MPa (60.9 ksi) — weaker than 94% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is P275NH N-70-100 easy to machine?
Reasonably — machinability is rated good (61/100, better than 87% of steel grades). Machines like normalized C-Mn steel (~65 % of AISI 1212); use sharp positive-rake carbide, moderate speeds, and expect gummy chips at low S levels.
Can P275NH N-70-100 be welded?
Yes — weldability is rated excellent (88/100). Excellent weldability with CEV typically ≤ 0.40; SAW/SMAW/GMAW with low-hydrogen consumables, preheat 50–100 °C for thick sections, PWHT 550–620 °C when required by EN 13445 / PED.
What surface finishes work on P275NH N-70-100?
No anodizing; shot-blast to Sa 2½ then epoxy/zinc-rich primer, hot-dip galvanize or weld-overlay clad for corrosive duty.
Can P275NH N-70-100 be formed, bent or molded?
Cold rollable into shells with generous bend radii (≥ 2t for t ≤ 20 mm); hot forming 850–1000 °C followed by re-normalizing to restore fine-grain properties.
What is the maximum service temperature of P275NH N-70-100?
P275NH N-70-100 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between P275NH-N and P275NH N-50-70?
N is the default condition — standard stocked delivery condition for thin pressure-vessel plate with full 275 MPa yield. N-50-70: thick plate for large tanks; yield 235 MPa min and lower tensile band. Yield strength is 300 MPa in N versus 260 MPa in N-50-70.
Sources
- EN 10028-3 Flat products made of steels for pressure purposes — Part 3: Weldable fine grain steels, normalized — CEN (2017)
- EN 10164 Steel products with improved deformation properties perpendicular to the surface — CEN (2018)
- EN 13445-3 Unfired pressure vessels — Design — CEN (2021)
- ASTM A516/A516M Pressure Vessel Plates, Carbon Steel, for Moderate- and Lower-Temperature Service — ASTM (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Pressure vessel plate P275NH data sheet — European plate mill (Dillinger/voestalpine typical) (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.