A662 Grade B is a low‑carbon, high‑strength structural steel plate specified under ASTM A662, commonly used in the fabrication of welded pressure vessels, storage tanks, and other structural components that require good toughness and weldability at moderate temperatures; it is typically supplied in the normalized condition and offers a balance of strength, ductility, and cost‑effectiveness for applications in the petrochemical, oil and gas, and general manufacturing industries.
A662GrB Adopted Processes
Hot Rolling Process: Raw steel billets are heated to 1100-1250℃ for uniform temperature distribution, then hot-rolled by controlled rolling technology. The rolling temperature and speed are precisely controlled to refine grain structure, improve material toughness and strength, and ensure uniform thickness and surface quality of steel plates.
Normalization Heat Treatment: This is the core post-rolling process. Steel plates are heated to 890-950℃, held for a certain time to achieve full austenitization, then cooled in air. It refines ferrite-pearlite microstructure, enhances dimensional stability, and guarantees low-temperature impact toughness.
Welding Process: Common processes include SMAW (Shielded Metal Arc Welding), GMAW (Gas Metal Arc Welding), FCAW (Flux-Cored Arc Welding) and SAW (Submerged Arc Welding). Preheating (60-150℃) is applied for thick plates, and post-weld heat treatment (PWHT) is conducted to reduce residual stress and improve weld joint toughness.
Forming & Machining Processes: Cold forming (bending, stamping) or hot forming is adopted for pressure vessel components. Machining uses high-speed cutting tools with appropriate parameters to ensure dimensional accuracy and surface finish. Ultrasonic flaw detection is performed after processing to eliminate internal defects.
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A662GrBChemical Composition |
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Grade |
The Element Max (%) |
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C |
Mn |
P |
S |
Si |
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A662GrB |
0.22 |
0.79-1.62 |
0.035 |
0.035 |
0.13-0.45 |
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Grade |
A662GrBMechanical Property |
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Thickness |
Yield |
Tensile |
Elongation |
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A662GrB |
mm |
Min Mpa |
Mpa |
Min % |
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200 |
275 |
450-585 |
20 |
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50 |
23 |
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advantages
Good strength and toughness balance:
A662GrB provides moderate to high tensile and yield strength, combined with acceptable ductility and impact toughness, especially after normalization. This allows it to withstand internal pressure, mechanical loads, and temperature fluctuations without premature failure, making it suitable for pressure vessel and storage tank applications.
Excellent weldability:
As a low-carbon, controlled-alloy steel, A662GrB can be readily welded using common processes such as SMAW, GMAW, FCAW, and SAW, with minimal preheating and post-weld heat treatment requirements in many cases. This simplifies fabrication, reduces production time and cost, and helps ensure reliable, defect-free joints in welded structures.
Cost-effective and readily available:
Compared with higher-strength or corrosion-resistant alloy steels, A662GrB offers a good performance-to-cost ratio. It is widely produced and stocked by steel mills and distributors, supporting shorter lead times and easier procurement for standard pressure vessel and tank projects, which contributes to overall project economy.
applications
Petrochemical Industry: As a core material, it is used to manufacture key equipment such as reactors, heat exchangers and separators, adapting to working conditions like crude oil processing and chemical synthesis. It can resist corrosion and pressure impact from medium and low temperature media, ensuring continuous production. It is also used in storage and transportation equipment such as liquefied petroleum gas cylinders and oil-gas storage tanks to meet the low-temperature storage needs of media.
Power Station and Boiler Field: It is used to manufacture core components such as boiler drums, nuclear power plant pressure vessels and high-pressure water pipes of hydropower stations. Adapting to complex working conditions such as high temperature, high pressure and low temperature pressure bearing in power stations, it can resist fatigue damage caused by frequent temperature fluctuations and ensure the safe and stable operation of the power system.
Cryogenic and Low-Temperature Equipment Field: Adapting to low-temperature working conditions such as -60℃, it is used in LNG secondary storage tanks, cryogenic separation equipment, ethylene cracking units, etc. It can still maintain good structural stability and toughness in low-temperature environments, avoiding the risk of low-temperature brittle fracture.
Other Pressure-Bearing Equipment: It is used to manufacture various medium and low temperature pressure-bearing equipment such as turbine volutes and liquefied oil cylinders, covering auxiliary production systems in multiple industries including energy, chemical industry and metallurgy, and adapting to pressure-bearing needs in different scenarios.
Contact us at beam@gneesteelgroup.com for pricing, technical support, or customized solutions. We are always ready to support your project.
What is the difference between A662GrB and A516Gr70?
A516Gr70 is a pressure vessel steel for higher temperatures, while A662GrB is optimized for low temperatures. A516Gr70 has higher strength, but A662GrB has better low-temperature toughness.
What quality control tests are required for A662GrB?
Required quality control tests include chemical composition analysis, tensile testing, yield strength testing, elongation testing, Charpy V-notch impact testing, and ultrasonic testing for internal defects.
Is A662GrB corrosion-resistant?
A662GrB has basic corrosion resistance in atmospheric environments but is not highly corrosion-resistant. For corrosive media (e.g., acids, salts), it requires protective coatings or corrosion-resistant alloys.
What is the form of supply for A662GrB?
A662GrB is mainly supplied as plates, but it can also be supplied as sheets, strips, or forgings upon request. The supply form depends on the application and customer requirements.
What is the minimum service temperature of A662GrB?
The minimum recommended service temperature of A662GrB is -29°C (-20°F), based on its Charpy V-notch impact test requirements. Using it below this temperature may compromise toughness.
Can A662GrB be used in cryogenic applications?
A662GrB is suitable for low-temperature applications but not for extreme cryogenic conditions (below -29°C/-20°F) unless specially tested and certified. For lower temperatures, cryogenic steel grades are preferred.
What is the hardness requirement for A662GrB?
The hardness of A662GrB is usually not specified in the standard but is typically around 120-160 HB (Brinell Hardness) in the as-rolled condition. Hardness testing may be required for quality control.
What is the maximum carbon content in A662GrB?
The maximum carbon content in A662GrB is 0.20%, as specified in ASTM A662/A662M. Controlling carbon content ensures good weldability and low-temperature toughness.
How to properly store A662GrB plates to avoid damage?
To prevent damage, A662GrB plates should be stored on wooden supports to avoid direct contact with the ground, kept in a dry and well-ventilated area, and covered with waterproof cloths to protect against moisture and contaminants.