Steel P355NL1
EN 1.0566, 10028-3
P355NL1 is a normalized fine-grain pressure vessel steel to EN 10028-3 (1.0566) qualified for improved low-temperature impact toughness, comparable to A537 Class 1, SPV355 and Q345R.
Reference datasheet — P355NL1 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
P355NL1 tempers and conditions
P355NL1 is supplied in 9 conditions, soft to hard. N is the default FabDigit quotes; the values on this page are for it.
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 |
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?
P355NL1 is a normalized fine-grain pressure vessel steel to EN 10028-3 (1.0566) qualified for improved low-temperature impact toughness, comparable to A537 Class 1, SPV355 and Q345R. It suits cold-climate and cryogenic equipment at 390 MPa yield, 550 MPa tensile, 28 % elongation and about 155 HB, and is listed in normalized thicknesses from plate up to 250 mm plus reduced-thickness and stress-relieved variants. Weldability is 88/100, but heat input must be controlled to protect the −40 °C impact values; formability is moderate (68/100) and bare surfaces rust quickly. Use P355N where sub-zero toughness is not required. P355NL1 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). P355NL1 has a yield strength of 390 MPa (56.6 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 64% of steel grades. Elongation at break is 28% and the elastic modulus is 210 GPa (30.5 Msi).
What is P355NL1 used for?
- cryogenic storage tanks
- cold-climate pressure vessels
- gas storage spheres
- pipeline components
Advantages
- Ductile — tolerates forming and impact — 28%, better than 89% of steel grades
- Tough — resists crack growth — 130 MPa·√m (118.3 ksi·√in), better than 89% 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
- Hard to polish — 45/100, worse than 84% of steel grades
P355NL1 properties
Typical room-temperature values for P355NL1-N; bars are the position among steel grades.
Physical3
P355NL1 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 has a yield strength of 390 MPa (56.6 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 64% of steel grades. Elongation at break is 28% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
P355NL1 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 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 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's machinability is good (55/100, better than 62% of steel grades); weldability excellent (88/100); formability good (68/100).
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. P355NL1 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with P355NL1
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.
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 |
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.
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 P355NL1 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- 1.056610028-3
- Similar grades
- A537 Class 1SPV355Q345R
How much does P355NL1 cost?
P355NL1 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.
P355NL1 — frequently asked
What is P355NL1 used for?
P355NL1 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?
P355NL1 has a typical yield strength of 390 MPa (56.6 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 64% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is P355NL1 easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% 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 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?
No anodizing; protect by shot blasting plus epoxy/zinc-rich paint, hot-dip galvanizing, metallizing or internal cladding — bare surfaces rust rapidly.
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 is the maximum service temperature of P355NL1?
P355NL1 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.
How much does P355NL1 cost?
P355NL1 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 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; 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.