Alloy Steel 11 / 22 / 91 Sheets & Plates

What are Alloy Steel Grades 11, 22 & 91 Sheets & Plates?

Alloy Steel Grade 11, 22, and 91 Sheets & Plates are chromium-molybdenum alloy steels widely used in high-temperature and high-pressure applications.

These grades conform to:

• ASTM A387 Grade 11
• ASTM A387 Grade 22
• ASTM A387 Grade 91

Key Functions:

• Withstand high pressure and temperature
• Provide excellent creep resistance
• Ensure durability in harsh environments
• Support structural and pressure vessel applications

Chemical Composition of Alloy Steel Grades

Grade 11 (1.25Cr – 0.5Mo)

• Chromium (Cr): 1.0% – 1.5%
• Molybdenum (Mo): 0.44% – 0.65%
• Carbon (C): ≤ 0.15%

Grade 22 (2.25Cr – 1Mo)

• Chromium (Cr): 2.0% – 2.5%
• Molybdenum (Mo): 0.87% – 1.13%
• Carbon (C): ≤ 0.15%

Grade 91 (9Cr – 1Mo)

• Chromium (Cr): 8.0% – 9.5%
• Molybdenum (Mo): 0.85% – 1.05%
• Vanadium (V), Niobium (Nb): Present
• Carbon (C): ≤ 0.12%

Higher chromium content improves oxidation resistance and high-temperature strength.

Key Features of Alloy Steel 11 / 22 / 91 Sheets & Plates

• Excellent high-temperature strength
• Superior creep and fatigue resistance
• Good resistance to oxidation and corrosion
• High pressure handling capability
• Long service life in extreme conditions
• Good weldability with proper procedures
• Suitable for power and petrochemical industries

Mechanical Properties

Grade 11:

• Tensile Strength: ~415 MPa
• Yield Strength: ~205 MPa

Grade 22:

• Tensile Strength: ~415–585 MPa
• Yield Strength: ~205 MPa

Grade 91:

• Tensile Strength: ~585–760 MPa
• Yield Strength: ~415 MPa

These properties ensure reliability under high stress and temperature.

Physical Properties

• Density: ~7.85 g/cm³
• Melting Range: ~1400–1450°C
• Modulus of Elasticity: ~200 GPa
• Thermal Conductivity: Moderate
• Thermal Expansion: Moderate

Corrosion & Heat Resistance

Alloy Steel 11/22/91 Sheets & Plates provide resistance to:

• High-temperature oxidation: Resistant
• Thermal fatigue: Good resistance
• Creep deformation: Low susceptibility
• Moderate corrosive environments: Suitable performance

Grade 91 offers superior performance in extreme heat conditions.

Heat Treatment

These alloy steels are supplied in normalized and tempered condition.

Heat Treatment Process:

• Solution Annealing: ~900–950°C
• Tempering: ~650–750°C

This enhances strength, toughness, and creep resistance.

Weldability

Alloy Steel Grades 11, 22, and 91 require controlled welding.

Welding Methods:

• SMAW
• TIG (GTAW)
• MIG (GMAW)

Best Practices:

• Preheating required
• Post Weld Heat Treatment (PWHT) recommended
• Controlled cooling

Machinability

• Moderate machinability
• Use carbide tools
• Maintain controlled cutting speeds
• Use proper lubrication

Standards & Specifications

Alloy Steel Sheets & Plates are manufactured according to:

• ASTM A387
• ASME SA387

These standards ensure global quality and performance compliance.

Available Forms

We offer:

• Sheets
• Plates
• Custom cut sizes

Surface Finish Options:

• Hot Rolled (HR)
• Normalized & Tempered
• Shot Blasted
• Machined

Sizes & Specifications

• Thickness: 3 mm to 150 mm
• Width: Up to 2500 mm
• Length: Custom sizes available

Applications of Alloy Steel 11 / 22 / 91 Sheets & Plates

Widely used in high-temperature industries:

• Power Plants: Used in boilers, pressure vessels, and heat exchangers.
• Oil & Gas Industry: Used in high-pressure pipelines and processing equipment.
• Petrochemical Industry: Used in reactors and high-temperature systems.
• Refineries: Used in heat-resistant components.
• Heavy Engineering: Used in structural and pressure applications.

Quality Testing & Inspection

Each product undergoes strict quality checks:

• Chemical composition testing
• Mechanical testing
• Dimensional inspection
• Ultrasonic testing (UT)
• Non-destructive testing (NDT)

Mill Test Certificates (MTC) are provided.

Packaging & Delivery

• Export-grade wooden packaging
• Protective wrapping
• Proper labeling and traceability
• Safe and timely global delivery

Why Choose Virami Steel Hub?

• Trusted alloy steel supplier in Mumbai
• Large inventory and ready stock
• Competitive pricing
• Custom manufacturing solutions
• Compliance with international standards
• Strong export network
• Dedicated customer support

Conclusion

Alloy Steel Grades 11, 22, and 91 Sheets & Plates (ASTM A387 Grade 11 / ASTM A387 Grade 22 / ASTM A387 Grade 91) are ideal for high-temperature and high-pressure applications. Their strength, creep resistance, and durability make them essential materials in power, petrochemical, and heavy industries.

Virami Steel Hub ensures top-quality alloy steel products that deliver long-term performance and reliability.