SA 387 GR 11 CL 1 / CL 2 – Chrome-Moly Alloy Steel for Elevated Temperature Pressure Systems SA 387 Grade 11 Class 1 and Class 2 are alloy steel plates combining 1.25% chromium and 0.5% molybdenum, engineered for use in high-temperature pressure vessels, heat exchangers, and thermal processing units. These plates deliver a dependable blend of oxidation resistance, moderate creep strength, and fabrication versatility, making them ideal for a wide range of thermal and industrial environments. Class 1 suits general high-temperature duties, while Class 2 offers enhanced tensile strength for higher-stress conditions. Key Benefits: Thermal Stability and Performance: Designed for operation in environments up to ~600°C, maintaining strength and resisting deformation over time. Corrosion and Oxidation Protection: Cr-Mo alloying ensures reliability in steam service, hydrogen atmospheres, and mildly corrosive conditions. Dual Strength Classes: Class 1 is suitable for standard pressure equipment, while Class 2 is tailored for heavier mechanical loads. Efficient Weldability and Workability: Supports conventional welding and forming methods with proper heat management, reducing fabrication complexity. Mechanical Properties Snapshot: Property SA 387 Gr 11 Cl 1 SA 387 Gr 11 Cl 2 Yield Strength ≥ 205 MPa ≥ 220 MPa Tensile Strength 415–585 MPa 515–690 MPa Elongation ≥ 20% ≥ 18% Max Service Temp Up to ~600°C Up to ~600°C Common Applications: Steam drums, thermal reactors, and pressure vessels Boilers and superheaters in power plants Equipment for refineries and petrochemical facilities Piping systems carrying high-temperature fluids or gases Summary: SA 387 GR 11 CL 1 / CL 2 plates offer reliable strength and resistance for elevated-temperature applications. With good mechanical integrity and adaptability in fabrication, they remain a dependable choice for thermal processing, chemical, and power generation systems where material performance is critical.