High-Carbon vs. Low-Carbon Steels for Forged Flanges

Carbon steel is a type of steel with 0.4% or less copper content, 1.65% or less manganese, and 0.6% or less silicon, according to the American Iron and Steel Institute. Carbon steel is divided into two general groups with different properties and different uses: low-carbon steel and high-carbon steel. While both types are defined by their carbon content, their uses differ in pressure vessel and API wellhead component manufacturing.

Low-Carbon Steels

Low-carbon steels, also called mild carbon steels, typically contains 0.05% to 0.25% carbon. These steels are inexpensive to produce and favor high machinability and ductility over hardness and tensile strength. Low-carbon steels are the preferred material for components such as piping and forged steel rings due to their high ductility and durability. They are also commonly used for automobile parts, steel plate, and blind flanges. The A516 family of steels is the most common type used for ASME pressure vessel connections forging.

High-Carbon Steels

Containing 0.3% to 1.7% carbon, high-carbon steels have significantly higher tensile strength and hardness than low-carbon varieties. However, higher carbon content also increases brittleness, making breaks and fractures more common. While high-carbon steels are not suitable for welding work, they are commonly used to manufacture knives, metal- and wood-cutting tools, and drill bits. High-carbon steels are generally considered less suited to custom pressure vessel components manufacturing due to their brittleness. But specific design constraints may require the high tensile strength of these steels for high pressure flanges.

Call Our Forged Flange Suppliers Today

Whether you need pressure vessel nozzle manufacturing or carbon steel flange manufacturing, Forged Components, Inc. can help. We provide seamless rolled ring forging and API blind manufacturing for custom pressure vessel connections. For more information or questions about the applications of carbon steel, stainless steel, or any other alloys, contact us online or call us at (281) 441-4088.