Materials database

Molybdenum-alloyed pressure vessel steel — THE European Mo-Kesselblech. Mo 0.25-0.35% improves creep resistance and elevated-temperature strength to ~500°C (higher than P265GH at ~400°C). Used for superheater tubes, boiler drums, steam piping, and heat exchangers in power generation. EN 10028-2 + PED.

Lowest-strength pressure vessel steel — ReH >=235 MPa. Excellent weldability due to very low C (max 0.16%). THE entry-level boiler/pressure vessel plate in EN 10028-2. Used for low-pressure vessels, boiler drums, heat exchangers, and steam piping at modest pressures and temperatures to ~400°C.

Unalloyed pressure vessel steel — THE standard boiler plate material in Europe. ReH >=265 MPa, good weldability, guaranteed elevated-temperature properties to ~450°C. "GH" = suitable for use at elevated temperatures. Used for boilers, pressure vessels, heat exchangers, and steam drums per EN 10028-2 and PED 2014/68/EU.

Weldable fine-grained non-alloy steel for pressure vessels with minimum yield strength 275 MPa. NH designation indicates normalized condition with impact testing at -20°C. Widely used entry-level pressure vessel grade for boilers, storage tanks, heat exchangers, and pipes transporting hot liquids. Good weldability without preheating for most thicknesses.

Weldable fine-grained non-alloy steel for pressure vessels with minimum yield strength 275 MPa and impact testing at -40°C (NL1 designation). Low-temperature variant of P275NH. Used for low-temperature pressure vessels, cryogenic storage tanks, and process equipment where guaranteed sub-zero toughness is required. Good weldability without preheating for most thicknesses.

Mid-range pressure vessel steel — ReH >=295 MPa. Between P265GH and P355GH. Used for unfired pressure vessels, heat exchangers, and boiler components per EN 10028-2. Good weldability and guaranteed elevated-temperature yield strength. Widely specified in European process plant design.

Higher-strength pressure vessel steel — ReH >=355 MPa, guaranteed elevated-temperature properties. Between P265GH and 16Mo3 in the pressure vessel hierarchy. Used for boilers, steam drums, heat exchangers, and pressure piping operating to ~400°C. EN 10028-2, PED 2014/68/EU compliant. Good weldability.

Weldable fine-grained non-alloy steel for pressure vessels with minimum yield strength 355 MPa in normalized condition. N designation indicates impact testing at room temperature. Widely used medium-strength pressure vessel grade for boilers, heat exchangers, storage tanks, and process vessels. Also standardized for seamless tubes (EN 10216-3) and welded tubes (EN 10217-3). Equivalent to ASTM A537 Class 1.

Weldable fine-grained non-alloy steel for pressure vessels with minimum yield strength 355 MPa. NH designation indicates normalized condition with specified elevated temperature properties and impact testing at -20°C. Very widely used pressure vessel grade for boilers, storage tanks, heat exchangers, and pipes transporting hot liquids and pressurized gases. Good weldability and resistance to brittle cracking.

Normalized pressure vessel steel with low-temperature toughness — ReH >=355 MPa, Charpy at -40°C (KV >=27J). "NL" = Normalized + Low-temperature. Used for pressure vessels, storage tanks, and process equipment operating in cold environments (LPG, cryogenic). EN 10028-3 + PED compliant.

Weldable fine-grained non-alloy steel for pressure vessels with minimum yield strength 355 MPa and impact testing at -40°C (NL1 designation). Low-temperature variant of P355NH for applications requiring guaranteed toughness at sub-zero temperatures. Used for cryogenic storage vessels, LNG/LPG tanks, and pressure equipment operating in cold environments. Equivalent to ASTM A737 Grade B.

Weldable fine-grained non-alloy steel for pressure vessels with minimum yield strength 355 MPa and impact testing at -50°C (NL2 designation). The most stringent low-temperature variant of the P355 series with tightest P and S control. Used for cryogenic storage vessels, LNG tanks, and pressure equipment in extreme cold service. Commonly stocked by European plate distributors.

High-strength weldable fine-grained alloy steel for pressure vessels with minimum yield strength 460 MPa in normalized condition. N designation indicates impact testing at room temperature. Used for high-pressure boilers, large storage tanks, heavy process vessels, and pipeline components. Equivalent to DIN StE460 and API 5L Grade X70.

Highest-strength normalized pressure vessel fine-grain steel — ReH >=460 MPa. "N" = normalized, "H" = elevated temperature. Used for high-pressure vessels, boiler drums, and chemical reactors where maximum strength with guaranteed elevated-temperature properties is needed. EN 10028-3 + PED compliant. Good weldability due to fine grain and controlled CEV.

High-strength weldable fine-grained alloy steel for pressure vessels with minimum yield strength 460 MPa. NL1 designation indicates impact testing at -40°C in the transverse direction. Normalized condition. Used for boilers, pressure vessels, heat exchangers, storage tanks, and pipes transporting hot liquids in the petrochemical, oil and gas, and power generation industries.

High-strength weldable fine-grained alloy steel for pressure vessels with minimum yield strength 460 MPa and impact testing at -50°C (NL2 designation). Stricter P and S limits than P460NL1 for improved low-temperature toughness. Normalized condition. Used for cryogenic and low-temperature pressure vessel applications.