Steel P420NH
EN P420NH
P420NH (1.8932) is a normalized, low-nickel-alloyed fine-grain pressure vessel steel to EN 10028-3 intended for elevated-temperature service up to 400 °C.
Reference datasheet — P420NH is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the N condition
P420NH tempers and conditions
P420NH is supplied in 4 conditions, soft to hard. N is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
N, heavy gauge | Same normalized condition but ordered in heavy plate, where EN 10028-3 lowers the guaranteed yield and tensile bands. | 380 | 580 | 25 | 175 HB | 8 % IACS |
Normalized then stress-relieved / PWHT | Condition of the finished vessel after code-required post-weld heat treatment; expect a small loss of proof strength. | 440 | 595 | 26 | 175 HB | 8 % IACS |
Normalized and tempered | Optional mill tempering after normalizing for tighter hardness scatter and slightly better toughness uniformity in heavy sections. | 455 | 600 | 25 | 180 HB | 8 % IACS |
NDefault Normalized | Standard mill delivery condition for pressure-vessel plate; use unless the fabricator specifies PWHT or through-thickness testing. | 460 | 620 | 24 | 185 HB | 8 % IACS |
Supply forms, finishes and certifications
Ways P420NH is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Z35 | Through-thickness ductility class per EN 10164 | Certification |
What is P420NH?
P420NH (1.8932) is a normalized, low-nickel-alloyed fine-grain pressure vessel steel to EN 10028-3 intended for elevated-temperature service up to 400 °C. It is chosen for code boiler and vessel plate that needs 420-class yield at temperature together with straightforward weldability, and is offered in N, N+T, N+SR and Z35 conditions including heavy plate. Default N values are 460 MPa yield, 620 MPa tensile, 24 % elongation and 185 HB, with weldability 80 and formability 58. CEV around 0.43 keeps preheat modest; P460NH is the higher-strength alternative. P420NH has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). P420NH has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 55% of steel grades. Elongation at break is 24% and the elastic modulus is 210 GPa (30.5 Msi).
What is P420NH used for?
- boiler and pressure vessel plate
- petrochemical reactors
- high-temperature piping
Advantages
- Readily welded — 80/100, better than 79% of steel grades
P420NH properties
Typical room-temperature values for P420NH-N; bars are the position among steel grades.
Physical3
P420NH has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
P420NH has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 55% of steel grades. Elongation at break is 24% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
P420NH is rated for continuous service to 400°C (752 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
P420NH conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (13/100), better than 66% of steel grades.
Sustainability4
Producing a kilogram of P420NH takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
P420NH's machinability is good (55/100, better than 62% of steel grades); weldability very good (80/100); formability good (58/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. P420NH is highlighted; hover a dot for its name, or open the interactive family chart.
Working with P420NH
Is P420NH easy to machine?
Machines like a normalized 500–600 MPa low-alloy steel — carbide tooling, moderate speeds, good chip control; slightly gummier than free-machining grades due to low sulphur.
Can P420NH be welded?
Readily weldable by SAW/SMAW/GMAW with matching low-hydrogen consumables; CEV ≈ 0.43 so preheat 100–150 °C for t > 30 mm, control heat input to protect HAZ toughness, PWHT per vessel code.
Can P420NH be formed, bent or molded?
Cold-forms and rolls into shells at generous bend radii (≥ 2.5–3 t); hot forming 850–950 °C must be followed by re-normalizing to restore the fine-grain properties.
P420NH 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 | ≤ 0.2 | 0.16 |
| Si | ≤ 0.5 | 0.35 |
| Mn | 1 – 1.7 | 1.45 |
| PNH grade limit | ≤ 0.03 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| Altotal Al, grain refining | ≥ 0.02 | 0.04 |
| N | ≤ 0.02 | 0.01 |
| Cr | ≤ 0.3 | 0.1 |
| Cu | ≤ 0.7 | 0.2 |
| Mo | ≤ 0.1 | 0.04 |
| Nilow nickel alloying for toughness | ≤ 0.8 | 0.45 |
| Nb | 0.02 – 0.05 | 0.03 |
| Ti | ≤ 0.03 | 0.01 |
| VNb+Ti+V ≤ 0.22 combined | 0.1 – 0.2 | 0.14 |
| Fe | balance |
What surface finishes work on P420NH?
No inherent corrosion resistance — shot-blast to Sa 2½ then zinc-rich primer, epoxy paint, hot-dip galvanizing or weld-overlay/clad for wet and chloride service.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel P420NH in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- 1.8932
How much does P420NH cost?
P420NH is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
P420NH — frequently asked
What is P420NH used for?
P420NH is typically used for boiler and pressure vessel plate, petrochemical reactors and high-temperature piping. In short: elevated-temperature vessel plate; low CEV, easy welding; below P460NH in strength.
What is the yield strength of P420NH?
P420NH has a typical yield strength of 460 MPa (66.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 55% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is P420NH easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machines like a normalized 500–600 MPa low-alloy steel — carbide tooling, moderate speeds, good chip control; slightly gummier than free-machining grades due to low sulphur.
Can P420NH be welded?
Yes — weldability is rated very good (80/100). Readily weldable by SAW/SMAW/GMAW with matching low-hydrogen consumables; CEV ≈ 0.43 so preheat 100–150 °C for t > 30 mm, control heat input to protect HAZ toughness, PWHT per vessel code.
What surface finishes work on P420NH?
No inherent corrosion resistance — shot-blast to Sa 2½ then zinc-rich primer, epoxy paint, hot-dip galvanizing or weld-overlay/clad for wet and chloride service.
Can P420NH be formed, bent or molded?
Cold-forms and rolls into shells at generous bend radii (≥ 2.5–3 t); hot forming 850–950 °C must be followed by re-normalizing to restore the fine-grain properties.
What is the maximum service temperature of P420NH?
P420NH 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 P420NH-N and P420NH N-thick?
N is the default condition — standard mill delivery condition for pressure-vessel plate; use unless the fabricator specifies PWHT or through-thickness testing. N-thick: same normalized condition but ordered in heavy plate, where EN 10028-3 lowers the guaranteed yield and tensile bands. Yield strength is 460 MPa in N versus 380 MPa in N-thick.
How much does P420NH cost?
P420NH is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- EN 10028-3 — Flat products of steels for pressure purposes: 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)
- EN 1011-2 — Welding recommendations for ferritic steels — CEN (2001)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- Fine-grain pressure vessel plate EN 10028-3 data sheets — European plate mills (Dillinger / Voestalpine / Industeel) (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.