ASTM A387 Grade 22
ASTM A387 Grade 22 is a chromium-molybdenum alloy steel plate specifically developed for welded boilers, pressure vessels, heat exchangers, reactors, and other high-temperature industrial equipment. With a chemical composition based on approximately 2.25% chromium and 1.0% molybdenum, this alloy steel grade delivers excellent elevated-temperature strength, creep resistance, oxidation resistance, and long-term thermal stability. It is widely used in industries such as oil and gas, petrochemical processing, power generation, chemical manufacturing, and refineries where equipment must operate safely under high pressure and continuous heat exposure.
The chromium content in ASTM A387 Grade 22 improves oxidation resistance, corrosion resistance, and high-temperature durability, while the molybdenum enhances tensile strength, creep resistance, and structural integrity during prolonged service at elevated temperatures. These properties make the material highly suitable for fabrication of pressure-retaining components exposed to severe operating environments, including hydrogen service, thermal cycling, and aggressive process conditions. The plate is commonly supplied in normalized and tempered condition to achieve balanced mechanical properties, improved toughness, and reliable weldability.
ASTM A387 Grade 22 alloy steel plate is frequently applied in refinery vessels, catalytic cracking units, steam boilers, pressure drums, separators, storage tanks, piping systems, and heat recovery equipment. Its excellent weldability allows it to be fabricated into complex pressure vessel structures using conventional welding processes while maintaining mechanical performance after heat treatment. The material is also valued for its resistance to creep deformation, which is critical in applications involving long-term exposure to elevated temperatures and stress.
Manufacturers produce ASTM A387 Grade 22 plates in multiple thicknesses, widths, and specifications to meet international pressure vessel standards and project requirements. The steel can comply with ASME SA387 Grade 22 requirements for boiler and pressure vessel construction and is commonly used in both domestic and international energy infrastructure projects. Due to its combination of heat resistance, mechanical strength, oxidation resistance, and fabrication versatility, ASTM A387 Grade 22 remains one of the most widely used Cr-Mo alloy steel plates for high-temperature pressure vessel and boiler service.