P355NL1, P355NL2, P355NH, P355GH, 1.0565, 1.0566, 1.0473 – mild, structural steel

P355 grade steel is a high quality structural material with excellent mechanical properties.
P355 steel is mild, fine grain structural steel that is often used in pressure vessels and boilers. Its high strength and corrosion resistance make it the ideal choice for use in demanding industrial applications.

Subgrades of P355 grade steel

P355 grade steel is divided into several subgrades which differ in their specific properties:
1. P355GH: This steel is designed for high-temperature applications and is characterized by high strength at temperatures up to 500 °C.
2. P355NH: This steel is designed for low-temperature applications and is characterized by high toughness at low temperatures.
3. P355NL1 and P355NL2: These steel subgrades are designed for applications where high toughness at low (P355NL1), very low (P355NL2) temperatures and good weldability are required.

In terms of mechanical properties, namely tensile strength, these subgrades are equal, but the value of the yield strength differs between them (it is slightly higher for P355NH). This difference affects the load capacity of the individual alloys belonging to this grade and consequently the possibilities of their use.

Application of P355 grade steel in industry

Due to its excellent properties, P355 grade steel is used in many industrial sectors. The most common use includes:
• Energy: Manufacture of pressure vessels and boilers, production of steam turbines, pipelines for transport of hot liquids and gases.
• Petrochemical industry: Manufacture of reactors, heat exchangers and other oil processing equipment.
• Construction: Manufacture of structural components for high-rise buildings, bridges, and other infrastructure projects.

P355 grade is also referred to as boiler steel.

Steel alloys, which are suitable for the construction of pressure vessels for the storage and transport of liquids and gases under pressure due to their properties and characteristics, are generally referred to as boiler or boilermaking steels.

Pressure vessels and transport piping are manufactured from special steels such as P355 grade, which can withstand considerable differences between internal and external pressure of these vessels and equipment, and which also exhibit a high degree of corrosion and impact resistance, even at low temperatures.

Various types of P355 grade steel and other boiler grade steels such as A516 (A516.60 and A516.70), SA 516 (SA 516.60 and SA 516.70), SA 105 according to ASME classification are used for the construction of pressure tanks and vessels, heat exchangers, piping and other components required for the storage and transportation of gases and liquids under pressure.

The manufacture of boiler steels is defined by pressure vessel regulations such as PED (Europe) and ASME (USA and Canada). The process of their production is defined from the stage of selection of raw materials, through the production itself, to the final testing of material properties. This ensures their safe use.

In our range you can also find other so-called boiler steels such as P250GH and P265GH, which we keep in stock.