From oil rigs to transmission towers, steel plate materials are used for many energy infrastructure projects.

The materials are mainly used to construct energy production and transmission structures. These structures are highly regulated to ensure they can withstand great forces, as energy infrastructure failures could have devastating environmental and societal impacts.

Additionally, materials used in energy applications must be machinable enough to be formed into structural shapes, without sacrificing strength and durability.

This article will explore the properties and applications of steel plate grades that are commonly used in energy sector applications and readily stocked by steel plate suppliers like Leeco® Steel.

Properties & Applications of Primary Energy Sector Grades

A wide range of steel plate materials are used in the energy sector, as different material properties are necessary for different applications and environments. The properties and applications of these materials will be explored below.

Structural Mild & HSLA Steel

ASTM A871 and ASTM A606 are two structural grades of structural mild and high strength low alloy (HSLA) steel plate used in energy applications. These categories of steel plate contain strengthening alloys and have a carbon composition between 0.05-0.25%.

 These grades have chemical properties that make them resistant to corrosion and wear from harsh weather conditions, but that also allow them to be formed into structural shapes with ease.

Chemical Composition of ASTM A871 and ASTM A606

Chemical

Alloy

A871 Grade 60 & 65: Type I

A871 Grade 60 & 65: Type II

A871 Grade 60 & 65: Type IV

A606 Type II & IV

A606 Type V

Carbon

0.19% MAX

0.20% MAX

0.17% MAX

0.22%

0.09%

Manganese

0.80-1.35%

0.75-1.35%

0.50-1.20%

1.25%

0.70-0.95%

Phosphorus

0.030% MAX

0.030% MAX

0.030% MAX

N/A

0.025%

Sulfur

0.030% MAX

0.030% MAX

0.030% MAX

0.04%

0.010%

Silicon

0.30-0.65%

0.15-0.50%

0.25-0.50%

N/A

0.40%

Copper

0.25-0.40%

0.20-0.40%

0.30-0.50%

0.20% MIN

0.65-0.98%

Nickel

0.40% MAX

0.50% MAX

0.40% MAX

N/A

0.52-0.76%

Chromium

0.40-0.70%

0.40-0.70%

0.40-0.70%

N/A

0.30%

Titanium

N/A

N/A

N/A

N/A

0.015%

Vanadium

0.02-0.10%

0.01-0.10%

N/A

N/A

0.015%

Niobium

N/A

N/A

N/A

N/A

0.08%

Columbium

N/A

N/A

0.005-0.05%

N/A

N/A

 

The strengthening alloys present in these materials give them a high yield point – which is the point of stress at which a material will change shape – and tensile strength – which is the point at which a material will bend and break – relative to their weight. This allows the materials to bear heavy loads without breaking or failing.

Mechanical Properties of ASTM A871 and ASTM A606

Grade

Yield Point

Tensile Strength

A871 Grade 60

60 ksi

75 ksi

A871 Grade 65

65 ksi

80 ksi

A606 Type II & IV – As-Rolled

50 ksi

70 ksi

A606 Type II & IV – Annealed or Normalized

45 ksi

65 ksi

 

With their balance of strength, durability and machinability, A871 and A606 are typically used in energy tubular structures and poles, such as those used in transmission towers or wind turbines.

 

Quenched & Tempered (Q&T) Steel

To further enhance strength – and increase toughness and hardness – some plate grades are heat treated through a process called quenching and tempering, which follows two stages of intense heating and cooling:

  • Quenching: The material is heated to a temperature between 1,500- and 1,650-degree Fahrenheit, then rapidly cooled with water.
  • Tempering: After being quenched, the material is then re-heated to a below-critical temperature – between 300 and 700 degrees, then air-cooled.

Related: Exploring Steel Plate Heat Treatment Processes

After being heat treated, the material is then age hardened – a process of aging a material by either heating it or storing it at a low temperature – to increase yield and tensile strength, toughness and machinability.

ASTM A710 is a low carbon Q&T steel grade containing chemical alloys that promote material strength and machinability.

Chemical Composition of ASTM A710

Chemical Alloy

A710 Grade A

A710 Grade B

Carbon

0.07%

0.03-0.09%

Manganese

0.40-0.70%

0.45-1.30%

Phosphorus

0.025%

0.025%

Sulfur

0.025%

0.025%

Silicon

0.40%

0.30-0.50%

Nickel

0.70-1.00%

0.80-1.00%

Chromium

0.60-0.90%

0.30%

Molybdenum

0.15-0.25%

0.25%

Copper

1.00-1.30%

1.25-1.50%

Columbium

0.02%

0.02-0.06%

Titanium

N/A

0.01-0.03%

 

A710 also has enhanced yield and tensile strengths due to the Q&T process.

Mechanical Properties of ASTM A710

Grade

Yield Point

Tensile Strength

A710 Grade A

50-85 ksi

60-90 ksi

A710 Grade B

70-75 ksi

80-85 ksi

 

Due to A710 plate’s ability to endure excessive, constant forces from weather conditions, it is typically used in jack up rigs, such as those used for offshore oil drilling or offshore wind turbines.

 

Pressure Vessel Quality (PVQ) Steel

Pressure vessel quality (PVQ) steel is used to produce pressure vessels in the oil and gas industry. These vessels store liquids or gases that have a pressure significantly different than that of the pressure outside the container.

ASTM A516 and ASTM A537 are the most common grades of PVQ steel plate, as these materials balance strength and machinability, which is crucial in the manufacturing of pressure vessels.

 A516 is a low-to-medium carbon steel with high strength relative to its weight and high machinability. A537 is highly machinable as well, but is also quenched and tempered to give the material greater strength and hardness.

Chemical Composition of ASTM A516 and ASTM A537

Chemical

Alloy

A516 Grade 55

A516 Grade 60

A516 Grade 65

A516 Grade 70

A537

Carbon

0.18-0.26%

0.21-0.27%

0.24-0.29%

0.27-0.31%

0.24%

Manganese

0.60-1.20%

0.60-1.20%

0.85-1.20%

0.85-1.20%

0.70-1.60%

Phosphorus

0.025%

0.025%

0.025%

0.025%

0.025%

Sulfur

0.025%

0.025%

0.025%

0.025%

0.025%

Silicon

0.15-0.40%

0.15-0.40%

0.15-0.40%

0.15-0.40%

0.15-0.50%

Copper

N/A

N/A

N/A

N/A

0.35%

Nickel

N/A

N/A

N/A

N/A

0.25%

Chromium

N/A

N/A

N/A

N/A

0.25%

Molybdenum

N/A

N/A

N/A

N/A

0.08%

 

Both grades have high yield and tensile points, which allow the material to endure high stresses and bear heavy weight without breaking or deforming.

Mechanical Properties of ASTM A516 and ASTM A537

Grade

Yield Point

Tensile Strength

A516 Grade 55

30 ksi

55-75 ksi

A516 Grade 60

32 ksi

60-80 ksi

A516 Grade 65

35 ksi

65-85 ksi

A516 Grade 70

38 ksi

70-90 ksi

A537 Class 1 ≤ 2.5” Thick

50 ksi

70 ksi

A537 Class 1 ≥ 2.5” Thick

45 ksi

65 ksi

A537 Class 2 ≤ 2.5” Thick

60 ksi

80 ksi

A537 Class 2 ≥ 2.5” Thick to 4” Thick

55 ksi

75 ksi

A537 Class 2 ≥ 4” Thick to 6” Thick

46 ksi

70 ksi

A537 Class 3 ≤ 2.5” Thick

55 ksi

80 ksi

A537 Class 3 ≥ 2.5” Thick

50 ksi

75 ksi

A537 Class 3 ≥ 4” Thick to 6” Thick

40 ksi

70 ksi

 

With high strength and ease of weldability, A516 and A537 plate is typically used to construct aboveground storage tanks, belowground storage tanks and pressurized railroad tank cars that store oil, gases, fuels and petrochemicals.

 A516 plate is available for current Leeco customers to purchase online via Leeco Pro, anytime, anywhere. Not yet a Leeco Pro user? Learn more or register today.

Offshore Steel Plate

Offshore steel plate, used in offshore energy applications, is produced with chemical alloys that resist corrosion, increase strength and toughness and reduce brittleness to resist great forces from waves and wind.

API 2H steel plate is certified by the American Petroleum Institute (API) for use in offshore structures in the oil and gas industry, such as oil rigs. This material contains chemical alloys that increase strength, weldability and impact resistance to ensure the material is able to endure ongoing forces from marine conditions.

 Chemical Properties of API 2H Steel Plate

Chemical

Alloy

API 2H

Grade 42

API 2H

Grade 50

Carbon

0.18%

0.18%

Manganese

0.90-1.35%

1.15-1.60%

Phosphorus

0.030%

0.030%

Sulfur

0.010%

0.010%

Silicon

0.05-0.40%

0.05-0.40%

Colombium

0.04%

0.01-0.04%

Titanium

0.020%

0.020%

Aluminum

0.02-0.06%

0.02-0.06%

Nitrogen

0.012%

0.012%

 

The chemical profile of API 2H plate makes the material strong, while also maintaining the ability to weld and machine with relative ease.

 Mechanical Properties of API 2H Steel Plate

Grade

Yield Point

Tensile Strength

API 2H Grade 42

42 ksi

62-82 ksi

API 2H Grade 50

47-50 ksi

70-90 ksi

 

Less Common Energy Sector Grades

While the steel plate grades listed above are those most commonly used in energy applications, other steel plate grades may be suitable for more specific energy applications.

Grade

Common Uses

ASTM A283

Producing pressure tanks and other welded structures.

ASTM A612

Producing pressure vessels for use in moderate and lower temperatures.

ASTM A285

Producing fusion-welded pressure vessels.

 

Sourcing Steel Plate For Energy Applications

When determining the best steel plate source for energy applications, it is crucial to look for a plate supplier who has a large stock of various plate grades and detailed paperwork to ensure materials meet necessary specifications.

Leeco Steel has 11 strategically-located distribution centers across North America with an ample stock of core grades used in energy applications. Leeco is also ISO 9001 certified in quality management to ensure materials meet quality standards and provides detailed paperwork with every order, including MTRs.

Contact Leeco Steel today to request a quote or discuss your energy sector plate needs with a knowledgeable representative.