SA 387 Grade 11 Class 2 is a chromium-molybdenum alloy steel plate compliant with ASME standards, mainly designed for high-temperature and pressure-bearing service. It undergoes normalizing and tempering heat treatment, featuring low phosphorus content to enhance brittleness resistance and good impact toughness even at low temperatures.
Specifications for ASME SA387 Grade 11 Class 2 Alloy Steel Plates
| Designation | Nominal Chromium Content (%) |
Nominal Molybdenum Content (%) |
| SA387 Grade 11 | 1.25% | 0.50% |
Chemical Requirements for ASME SA387 Grade 11 Class 2 Alloy Steel Plates
| Element | Chemical Composition (%) | |
| SA387 Grade 11 | ||
| Carbon: | Heat Analysis: | 0.05 - 0.17 |
| Product Analysis: | 0.04 - 0.17 | |
| Manganese: | Heat Analysis: | 0.40 - 0.65 |
| Product Analysis: | 0.35 - 0.73 | |
| Phosphorus: | Heat Analysis: | 0.035 |
| Product Analysis: | 0.035 | |
| Sulphur (max): | Heat Analysis: | 0.035 |
| Product Analysis: | 0.035 | |
| Silicon: | Heat Analysis: | 0.50 - 0.80 |
| Product Analysis: | 0.44 - 0.86 | |
| Chromium: | Heat Analysis: | 1.00 - 1.50 |
| Product Analysis: | 0.94 - 1.56 | |
| Molybdenum: | Heat Analysis: | 0.45 - 0.65 |
| Product Analysis: | 0.45 - 0.70 |
Key Applications
Oil & Gas Industry
This material serves as a critical structural solution for pressure vessels, heavy-duty piping systems, and fluid-handling equipment dedicated to the storage and transportation of oil, gas, and related fluids under elevated temperature conditions. It is specifically engineered to withstand the harsh operating parameters common in upstream exploration, midstream transmission, and downstream refining segments, ensuring long-term integrity and reliability even when exposed to fluctuating pressure loads and corrosive media inherent in the oil and gas value chain.
Petrochemical & Chemical Processing Industry
It is widely adopted in the fabrication of core process equipment, including reactors, shell-and-tube heat exchangers, and storage vessels deployed in demanding chemical environments. These applications often involve exposure to aggressive substances such as strong acids, alkalis, organic solvents, and high-temperature reaction mixtures. The material's robust chemical resistance and structural stability make it ideal for sustaining continuous operation in petrochemical plants, specialty chemical manufacturing facilities, and pharmaceutical production lines where equipment performance directly impacts process efficiency and safety.
Power Generation Industry
The material is a preferred choice for manufacturing key components of power generation systems, such as boiler pressure parts (including boiler tubes, headers, and drums) and auxiliary equipment operating under extreme high-temperature and high-pressure conditions. It is extensively used in thermal power plants, nuclear power auxiliary systems, and concentrated solar power (CSP) facilities, where it resists thermal fatigue, creep deformation, and oxidation-factors that are critical for maintaining the efficiency and longevity of power generation infrastructure.
Fabrication Sector for Pressure Equipment
It is a staple material for the fabrication of welded boilers, compact heat exchangers, and pressure vessels that mandate high mechanical strength, exceptional high-temperature creep resistance, and superior oxidation resistance. Fabricators rely on its weldability and dimensional stability to produce equipment that complies with stringent industry standards (e.g., ASTM, ASME, EN). This material is particularly suitable for custom-built pressure-bearing components used in industries where equipment operates beyond the performance limits of conventional carbon steels, ensuring compliance with safety and quality regulations.
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1.What is SA 387 11 2 material?
SA 387 GR. 11 CL. 2 Plate is a heat-resistant and corrosion-resistant steel plate that is resistant to high temperatures, stress and creep. sa 387 gr 11 cl 2 material also has good impact strength and weldability.
2.What is the difference between SA 387 Grade 11 Class 2 and Class 1 steel?
SA 387 Grade 11 Class 2 steel offers higher tensile and yield strength than Class 1 due to stricter heat treatment (normalized and tempered), making it suitable for more demanding, high-stress, high-temperature applications like pressure vessels, while both share the same chemical composition (Chromium-Molybdenum alloy) but differ in mechanical performance, with Class 2 providing greater load-bearing capacity.