SA 387 GR 9 CL 1 / CL 2 – Chromium-Molybdenum Alloy Steel Plate for Elevated Temperature Service SA 387 Grade 9 Class 1 and Class 2 plates are chrome-moly alloy steels designed specifically for pressure vessels and boilers operating in elevated temperature environments. With approximately 9% chromium and 1% molybdenum, these plates offer outstanding resistance to oxidation, thermal fatigue, and corrosion in high-heat and hydrogen-rich environments. Used widely in the petrochemical, power generation, and oil & gas sectors, SA 387 GR 9 CL 1/2 plates provide both strength and reliability in critical applications. Key Highlights: High Chromium Content (9%): Provides superior resistance to scaling and oxidation at high temperatures. Optimized for Elevated Temperature Service: Excellent creep strength and thermal stability under prolonged exposure to heat and pressure. Two Classes Available: Class 1: Lower tensile strength, suitable for moderate pressure conditions. Class 2: Higher tensile strength for more demanding applications. Good Weldability and Fabrication: Compatible with standard welding processes when proper preheat and post-weld heat treatment are applied. Mechanical Properties Overview: Property SA 387 Gr 9 Cl 1 SA 387 Gr 9 Cl 2 Yield Strength ≥ 220 MPa ≥ 240 MPa Tensile Strength 415–585 MPa 515–690 MPa Elongation ≥ 20% ≥ 18% Temperature Resistance Up to ~650°C (1200°F) Up to ~650°C (1200°F) Typical Applications: Petrochemical Processing Units: Pressure vessels and reactors handling corrosive and high-temperature media. Boiler and Heat Exchanger Construction: Components exposed to extreme heat and pressure cycles. Refineries and Hydrogen Service Equipment: Suitable for sour gas service and hydrogen embrittlement resistance. Thermal Power Plants: Steam piping, headers, and superheater tubes. Conclusion: SA 387 GR 9 CL 1 and CL 2 offer a dependable solution for pressure-retaining components in the most demanding thermal and chemical environments. With high chromium content and strong mechanical performance, they deliver the strength, oxidation resistance, and long-term reliability required in modern high-efficiency thermal systems.