Steel P355NL1-NR (Normalized rolled)
Heat-treated state
EN 1.0566, 10028-3
Mill-economical alternative to furnace normalizing; same guaranteed properties, but re-normalizing after hot forming may be required by the fabricator.
Values for the NR condition
Other P355NL1 tempers and conditions
P355NL1 is listed in 9 conditions; see the grade overview at P355NL1.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
N | Maximum plate thickness range; used for forged-like heavy sections, lowest guaranteed strength. | 320 | 505 | 25 | 140 HB | 8.6 % IACS |
N | Very heavy plate; strength drops to ReH ≥ 295 MPa and Rm band shifts to 470–610 MPa. | 330 | 515 | 26 | 143 HB | 8.6 % IACS |
N | Heavy-wall vessel and tube-sheet plate; ReH ≥ 315 MPa, through-thickness testing often added. | 350 | 530 | 26 | 146 HB | 8.6 % IACS |
N | Thick plate for tube sheets and heavy flanged shells; ReH ≥ 325 MPa. | 360 | 535 | 27 | 148 HB | 8.6 % IACS |
N | Heavy shell/nozzle-reinforcement plate; ReH ≥ 335 MPa. | 370 | 540 | 27 | 150 HB | 8.6 % IACS |
Normalized plus stress-relieved / simulated PWHT | Ordered when the vessel receives PWHT; slightly lower yield and hardness, best dimensional stability and residual-stress control. | 375 | 535 | 29 | 150 HB | 8.7 % IACS |
N | Medium plate for vessel shells; yield guarantee steps down to 345 MPa. | 380 | 545 | 28 | 152 HB | 8.6 % IACS |
NDefault Normalized | Standard stocked condition for thin plate; full 355 MPa yield and -40 °C impact guarantee. | 390 | 550 | 28 | 155 HB | 8.6 % IACS |
NRThis page Normalized rolled | Mill-economical alternative to furnace normalizing; same guaranteed properties, but re-normalizing after hot forming may be required by the fabricator. | 395 | 555 | 28 | 158 HB | 8.6 % IACS |
What is P355NL1-NR?
P355NL1-NR is P355NL1 heat treated to NR — mill-economical alternative to furnace normalizing; same guaranteed properties, but re-normalizing after hot forming may be required by the fabricator. P355NL1-NR has a yield strength of 395 MPa (57.3 ksi) and a tensile strength of 555 MPa (80.5 ksi) — weaker than 63% of steel grades. Elongation at break is 28% and the elastic modulus is 210 GPa (30.5 Msi). P355NL1-NR 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). N is the default condition FabDigit quotes; NR is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 135 MPa·√m (122.9 ksi·√in), better than 93% of steel grades
- Ductile — tolerates forming and impact — 28%, better than 89% of steel grades
- Readily welded — 88/100, better than 87% of steel grades
- Forms and bends easily — 70/100, better than 86% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
P355NL1-NR properties
Typical room-temperature values for P355NL1-NR; 22 are specific to this condition. Other listed values are P355NL1 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
P355NL1-NR 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
P355NL1-NR has a yield strength of 395 MPa (57.3 ksi) and a tensile strength of 555 MPa (80.5 ksi) — weaker than 63% of steel grades. Elongation at break is 28% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
P355NL1-NR is rated for continuous service to 400°C (752 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
P355NL1-NR conducts electricity at 8.6 % IACS, better than 66% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of P355NL1-NR takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 28%.
Manufacturability7
P355NL1-NR's machinability is fair (54/100, better than 54% of steel grades); weldability excellent (88/100); formability very good (70/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with P355NL1-NR
Is P355NL1 easy to machine?
Machines like normalized C-Mn steel (~60 % of AISI 1212): use coated carbide, moderate speeds and generous feed; slightly gummy chips, so chipbreaker geometry and coolant help.
Can P355NL1 be welded?
Excellent weldability with CEV ≤ 0.45 — SAW/SMAW/GMAW with low-hydrogen, matching 355-class consumables; preheat 100–150 °C for heavy sections and control heat input to protect the -40 °C toughness.
Can P355NL1 be formed, bent or molded?
Good cold formability for rolling shells and dishing heads (min bend radius ≈ 1.5–2 t); hot forming above 580 °C or heavy cold work usually requires re-normalizing to restore fine grain and impact values.
What surface finishes work on P355NL1?
No anodizing; protect by shot blasting plus epoxy/zinc-rich paint, hot-dip galvanizing, metallizing or internal cladding — bare surfaces rust rapidly.
P355NL1 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 ≤ 250 mm | ≤ 0.18 | 0.16 |
| Si | ≤ 0.5 | 0.35 |
| Mn | 1.1 – 1.7 | 1.45 |
| P | ≤ 0.03 | 0.01 |
| Slow S for through-thickness toughness | ≤ 0.02 | 0.01 |
| Altotal Al, grain refining | ≥ 0.02 | 0.04 |
| N | ≤ 0.02 | 0.01 |
| NbNb+Ti+V ≤ 0.12 | ≤ 0.05 | 0.03 |
| V | ≤ 0.1 | 0.03 |
| Ti | ≤ 0.03 | 0.01 |
| Crresidual | ≤ 0.3 | 0.08 |
| Niaids low-temperature toughness | ≤ 0.5 | 0.15 |
| Curesidual | ≤ 0.3 | 0.1 |
| Moresidual | ≤ 0.08 | 0.02 |
| Fe | balance | — |
P355NL1-NR — frequently asked
What is P355NL1-NR used for?
P355NL1-NR is typically used for cryogenic storage tanks, cold-climate pressure vessels, gas storage spheres and pipeline components. In short: −40 °C impact-tested plate; weldable low-temperature vessel steel; available to 250 mm thickness.
What is the yield strength of P355NL1-NR?
P355NL1-NR has a typical yield strength of 395 MPa (57.3 ksi) and a tensile strength of 555 MPa (80.5 ksi) — weaker than 63% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is P355NL1-NR easy to machine?
Reasonably — machinability is rated fair (54/100, better than 54% of steel grades). Machines like normalized C-Mn steel (~60 % of AISI 1212): use coated carbide, moderate speeds and generous feed; slightly gummy chips, so chipbreaker geometry and coolant help.
Can P355NL1-NR be welded?
Yes — weldability is rated excellent (88/100). Excellent weldability with CEV ≤ 0.45 — SAW/SMAW/GMAW with low-hydrogen, matching 355-class consumables; preheat 100–150 °C for heavy sections and control heat input to protect the -40 °C toughness.
What surface finishes work on P355NL1-NR?
No anodizing; protect by shot blasting plus epoxy/zinc-rich paint, hot-dip galvanizing, metallizing or internal cladding — bare surfaces rust rapidly.
Can P355NL1-NR be formed, bent or molded?
Good cold formability for rolling shells and dishing heads (min bend radius ≈ 1.5–2 t); hot forming above 580 °C or heavy cold work usually requires re-normalizing to restore fine grain and impact values.
What is the maximum service temperature of P355NL1-NR?
P355NL1-NR 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 P355NL1-N and P355NL1 N-50-70?
N is the default condition — standard stocked condition for thin plate; full 355 MPa yield and -40 °C impact guarantee. N-50-70: thick plate for tube sheets and heavy flanged shells; ReH ≥ 325 MPa. Yield strength is 390 MPa in N versus 360 MPa in N-50-70.
Sources
- EN 10028-3: Flat products made of steels for pressure purposes — Weldable fine grain steels, normalized — CEN (2017)
- GB/T 713 (Q345R) — SAC (2014)
- ASTM A537/A537M Heat-Treated Carbon-Manganese-Silicon Steel Plates — ASTM (2020)
- EN 13445-2/-3 Unfired pressure vessels — Materials and Design — CEN (2021)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Pressure vessel plate P355N/NH/NL1/NL2 data sheet — Dillinger / Salzgitter Flachstahl (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.