ASTM A387 Grade 11 Class 2 (A387GR11CL2) steel plates are primarily used in the manufacturing of welded boilers and pressure vessels for high-temperature and high-pressure applications in the petrochemical, power, and nuclear energy sectors, owing to their excellent high-temperature strength, corrosion resistance, and weldability.

Key Features and Advantages

1. Excellent High-Temperature Performance

Designed for elevated temperature service (up to 600°C / 1112°F), making it ideal for refineries, petrochemical plants, and power generation equipment. Maintains creep strength and oxidation resistance under prolonged heat exposure.

2. Excellent Corrosion & Sulfidation Resistance

Contains 1.25% chromium and 0.5% molybdenum, enhancing resistance to H₂S (sulfidation), CO₂, and acidic environments common in oil & gas operations.

3. Good Weldability & Fabrication Properties

Pre- and post-weld heat treatment (PWHT) minimizes cracking risks.

4. Cost-Effective for Medium-Harsh Environments

More economical than higher-grade alloys (e.g., 304/316 stainless steel) while offering sufficient strength and durability for moderate corrosive conditions.

ASTM A387 Grade 11 Class 2 (A387GR11CL2) steel plate is primarily used for manufacturing shells of pressure vessels and equipment serving in high-temperature and/or corrosive environments, such as:

1. Petrochemical industry: Hydrogeneration reactors, gasifiers, heat exchangers, capable of withstanding corrosive media like H₂S and CO₂.

2. Power industry: High-temperature high-pressure boiler drums and steam pipelines, suitable for long-term service at 316–593°C.

3. Coal chemical industry: Coal liquefaction units, synthetic ammonia reactors, with excellent resistance to hydrogen corrosion and high-temperature creep.

4. Nuclear energy sector: Components of nuclear reactor pressure vessels, required to meet the stringent specifications of ASME BPVC Section III.

Comparison: Class 1 vs. Class 2