P295GH steel plate is a high-strength, non-alloy, fine-grain structural steel produced by hot rolling, specifically designed for high-temperature pressure equipment. It is widely used in industrial boilers, pressure vessels, and pressure piping systems. Its technical requirements are primarily governed by the European standard EN 10028-2:2022 "Flat products made of steels for pressure purposes – Part 2: Non-alloy and alloy steels with specified elevated temperature properties". This standard is the core international specification widely adopted for pressure equipment steel plates, clearly defining chemical composition, mechanical properties, elevated temperature performance, impact toughness, dimensional tolerances, test methods, and quality assurance requirements for P295GH. As a key grade within the EN 10028-2 standard, P295GH is extensively used in Europe and in countries adopting the European Pressure Equipment Directive (PED), suitable for medium- and high-pressure equipment operating at temperatures up to 400°C.
The designation "P295GH" consists of four parts: "P" stands for "Pressure equipment", indicating the steel is intended for pressure vessels; "295" denotes the specified minimum yield strength at room temperature of 295 MPa, making it a higher-strength upgrade compared to P235GH and P265GH; "G" means "Guaranteed impact test" (the supplier must perform impact testing); and "H" signifies "specified elevated temperature properties", meaning the steel not only meets room-temperature mechanical requirements but also possesses good high-temperature strength, microstructural stability, and creep resistance, making it suitable for pressure components operating at elevated temperatures over long periods. P295GH is a fine-grain non-alloy steel, with carbon content strictly controlled (typically between 0.16%–0.22%) and elements such as aluminum (Al), niobium (Nb), or vanadium (V) added for deoxidation and grain refinement, ensuring good weldability, toughness, and high-temperature stability.
The primary applications of P295GH steel plate are in the energy, chemical, power generation, and heavy industrial sectors, suitable for manufacturing medium- and high-pressure boilers, pressure vessels, and heat exchange equipment. Typical applications include:
Boiler Manufacturing: Used for shells, headers, tube sheets, end caps, and other critical pressure-bearing components in large industrial boilers.
Pressure Vessels: Used in oil and chemical industries for reactors, separators, heat exchanger shells, and high-pressure storage tanks.
Piping Systems: Used as tube billets or connecting parts for high-temperature steam or thermal fluid pipelines.
Heat Exchange Equipment: Used for manufacturing high-pressure, large-diameter heat exchanger shells and other structures.
Key characteristics include: high room-temperature and elevated-temperature strength (maintaining excellent mechanical properties at 400°C), good weldability (typically requiring preheating of 150–200°C to prevent cold cracking), excellent cold and hot formability, and high impact toughness (Charpy V-notch impact testing required at 0°C or -20°C per standard). As a higher-strength, well-balanced high-temperature pressure material, P295GH holds an important position in the manufacturing of medium- and high-pressure equipment and is an ideal choice for replacing plain carbon steel to enhance pressure capacity, with widespread industrial application.
Ultrasonic Testing (UT)
A key non-destructive testing technique that uses high-frequency sound waves to detect internal flaws in steel plates. The probe emits sound waves, which reflect when encountering defects such as cracks or inclusions. The receiver captures the echoes, enabling precise determination of defect location and size. With high sensitivity, strong penetration, and fast inspection speed, UT effectively ensures internal quality, widely used in the production of heavy plates, pressure vessel plates, and other high-end products to guarantee safety and reliability.
Magnetic Particle Testing (MT)
A common surface inspection method that magnetizes the workpiece, causing leakage magnetic fields at surface or near-surface defects like cracks or inclusions, which attract magnetic particles to form visible indications. Simple to operate and highly sensitive, MT is suitable for rapid inspection of surface and near-surface flaws in ferromagnetic materials, widely used for online or offline inspection of plate edges, ends, and welds, ensuring product quality and safety.
Penetrant Testing (PT)
A non-destructive method for detecting surface-breaking flaws. A penetrant liquid is applied to the cleaned steel surface, allowing it to seep into defects such as cracks or pores. After removing excess penetrant, a developer is applied, causing the trapped penetrant to bleed out and form visible indications. Simple and cost-effective, PT is suitable for inspecting surface defects in various non-porous materials, commonly used for welds, castings, and complex components, effectively ensuring surface quality of steel plates.
