This comprehensive product introduction showcases the A387Gr91CL2/A387 Grade 91 Class 2 chromium-molybdenum alloy steel plate, tailored for pressure vessels and boilers operating under extreme high-temperature and high-pressure conditions. The article delves into its intricate chemical composition, remarkable mechanical properties, tailored heat treatment states, versatile size ranges, stringent impact testing requirements, diverse application scenarios, and specific supply cases by TJC Steel Group, ensuring readers gain a comprehensive understanding of this premium material.

1. Introduction

A387Gr91CL2/A387 Grade 91 Class 2, a chromium-molybdenum alloy steel plate conforming to ASTM A387/A387M standards, stands as a pillar of the pressure vessel and boiler industry. This material is renowned for its exceptional high-temperature strength, corrosion resistance, and long-term durability, making it the ideal choice for demanding applications.

2. Chemical Composition

The chemical composition of A387Gr91CL2 is meticulously balanced to achieve optimal performance. Key elements include:

- Carbon (C): 0.08% - 0.15%, providing strength while maintaining ductility and weldability.

- Silicon (Si): 0.20% - 0.50%, enhancing strength and hardness through solid solution strengthening.

- Manganese (Mn): 0.30% - 0.60%, improving strength, toughness, and hot workability.

- Phosphorus (P) and Sulfur (S): Limited to ≤ 0.035% each, minimizing embrittlement and improving overall quality.

- Chromium (Cr): 9.00% - 12.00%, crucial for corrosion and oxidation resistance, forming a protective oxide layer.

- Molybdenum (Mo): 0.85% - 1.05%, enhancing heat resistance, corrosion resistance, and toughness.

Additional elements such as nickel (Ni), nitrogen (N), aluminum (Al), vanadium (V), niobium (Nb), and boron (B) may be present in trace amounts, further refining material properties.

3. Mechanical Properties

A387Gr91CL2 boasts impressive mechanical properties, including:

- Yield Strength: ≥ 415 MPa

- Tensile Strength: 585-760 MPa

- Impact Toughness: Ensured through stringent impact testing at various temperatures, ensuring material integrity under dynamic loading.

4. Heat Treatment State

The steel plate undergoes rigorous heat treatment to achieve its optimal properties:

- Normalizing: At 1040°C - 1080°C, improving microstructure and mechanical properties.

- Tempering: Following normalizing, at 730°C - 800°C, stabilizing the microstructure, enhancing toughness and corrosion resistance.

5. Size Range

A387Gr91CL2 is available in a wide range of sizes to suit diverse applications:

- Thickness: 6mm - 100mm, catering to various design requirements.

- Width: 1000mm - 3000mm

- Length: 1000mm - 12000mm

Custom sizes and dimensions can be supplied upon request.

6. Impact Testing

Rigorous impact testing is conducted to ensure material integrity, including Charpy V-notch impact tests at various temperatures, ensuring the plate meets stringent standards for toughness and fracture resistance.

7. Main Application Scenarios

A387Gr91CL2 finds widespread application in:

- Petrochemical Industry: Reactors, heat exchangers, and pressure vessels exposed to corrosive environments.

- Power Generation: High-temperature steam piping, superheaters, reheaters, and economizers in thermal power plants.

- Nuclear Industry: High-temperature, high-pressure vessels and structural components requiring exceptional durability and safety.

- Shipbuilding: Critical high-temperature sections in vessels requiring resistance to corrosion and fatigue.