What is the Difference Between SA 516 GR 70 and SA 533 GR B Cl 2?

ASME SA 516 GR 70 is a carbon steel plate for moderate and low-temperature pressure vessels, while SA 533 GR B Cl 2 is an alloy steel for high-strength, high-pressure applications.At Gangsteel, we manufacture ASME SA 516 GR 70 plates optimized for standard pressure vessel needs. This article compares their composition, properties, and applications to guide material selection.

Overview of SA 516 GR 70 and SA 533 GR B Cl 2

ASME SA 516 GR 70, equivalent to ASTM A 516 GR 70, is a carbon steel plate specification designed for welded pressure vessels operating at moderate and low temperatures (down to -46°C). It is widely used for its high tensile strength (485-620 MPa), excellent weldability, and HIC resistance. ASME SA 533 GR B Class 2, a quenched and tempered alloy steel, is designed for high-pressure vessels requiring superior strength and toughness, often used in nuclear reactors and extreme environments.

Gangsteel’s SA 516 GR 70 plates are fine-grain treated, making them ideal for oil and gas applications, while SA 533 GR B Cl 2 is reserved for specialized, high-stress projects.

Chemical Composition Comparison

SA 516 GR 70 is a carbon steel with minimal alloying, while SA 533 GR B Cl 2 includes significant alloying elements like manganese and molybdenum for enhanced strength:

Gangsteel’s SA 516 GR 70 plates are tested for HIC per NACE TM0284, with sulfur content as low as 0.003%, making them suitable for sour gas environments. SA 533 GR B Cl 2’s alloying elements make it ideal for extreme conditions but increase production costs.

Mechanical Properties Comparison

SA 533 GR B Cl 2’s alloy composition and heat treatment result in higher strength and toughness:

SA 516 GR 70, as used in ASME SA 516 GR 65, is normalized for standard applications, while SA 533 GR B Cl 2 is quenched and tempered for enhanced performance in critical environments.

Heat Treatment Differences

• SA 516 GR 70: Normalized at 900-950°C or stress-relieved at 620-650°C to achieve a fine-grain structure, optimizing toughness and weldability.
• SA 533 GR B Cl 2: Quenched at 870-900°C and tempered at 620-650°C, resulting in a stronger, tougher microstructure for high-pressure and low-temperature service.
•  

Gangsteel’s SA 516 GR 70 plates are optimized for welding with components like ASME SA 516 GR 60, ensuring reliable performance.

Applications and Selection Criteria

• SA 516 GR 70 Applications:
  • Oil and Gas: High-pressure pressure vessels and pipelines, especially in sour gas environments.
  • Petrochemical: Reactors and heat exchangers requiring HIC resistance.
  • Power Generation: Boilers operating at moderate temperatures up to 450°C.
• SA 533 GR B Cl 2 Applications:
  • Nuclear Reactors: High-pressure vessels requiring superior strength and toughness.
  • Cryogenic Systems: Vessels in low-temperature environments.
  • Heavy-Duty Petrochemical: Reactors exposed to extreme pressures and temperatures.

Gangsteel recommends SA 516 GR 70 for most standard pressure vessel applications due to its cost-effectiveness and weldability. SA 533 GR B Cl 2 is reserved for specialized projects requiring exceptional strength and toughness.

Gangsteel’s Commitment to SA 516 Quality

Gangsteel ensures the quality of our SA 516 GR 70 plates through:

• Controlled Rolling: Produces fine-grain plates for enhanced toughness.
• Testing: Ultrasonic (ASTM A435), HIC (NACE TM0284), and impact tests at -46°C.
• Certifications: MTCs per EN 10204 3.1, verified by SGS and BV.

Our global supply chain supports exports to over 50 countries, with delivery to Asia in 3-7 days. Gangsteel’s SA 516 plates, such as ASTM A 516 GR 55, are designed for reliable performance.

Why Choose SA 516 GR 70 Over SA 533 GR B Cl 2?

SA 516 GR 70 offers advantages for standard applications:

• Cost-Effectiveness: Lower alloy content reduces production costs.
• Weldability: Fine-grain structure and low carbon content ensure easy fabrication.
• HIC Resistance: Ideal for sour service environments.

SA 533 GR B Cl 2 is preferred for high-pressure, low-temperature applications where its alloying and heat treatment provide superior performance, but its higher cost makes it less common for standard projects.

Conclusion

ASME SA 516 GR 70 is a carbon steel plate for moderate and low-temperature pressure vessels, offering high strength and HIC resistance, while SA 533 GR B Cl 2 is an alloy steel for high-pressure, high-toughness applications. Gangsteel’s ASME SA 516 GR 70 plates provide cost-effective, reliable solutions for standard pressure vessel needs. Contact Gangsteel for tailored plates that meet ASME standards.

Keywords: SA 516 GR 70 vs SA 533 GR B Cl 2, carbon steel vs alloy steel, pressure vessel plates, Gangsteel SA 516