What kind of steel is used in pipelines?

The type of steel commonly used in pipelines is known as pipeline steel or line pipe steel. It is typically a high-strength carbon steel that meets specific requirements for use in transporting fluids and gases over long distances. The two most commonly used grades of pipeline steel are:

API 5L Grade B: This is a widely used grade specified by the American Petroleum Institute (API). API 5L Grade B steel has good weldability and is suitable for pipeline applications in various industries, including oil and gas.

API 5L X52: This is another commonly used grade specified by API. API 5L X52 steel provides higher strength compared to Grade B and is often selected for pipelines operating under higher pressure or in more demanding conditions.

Pipeline steels are designed to have excellent mechanical properties, such as high tensile strength, good toughness, and resistance to cracking. They are also tested for specific parameters like chemical composition, impact toughness, and dimensional tolerance to ensure their suitability for pipeline applications.

It's important to note that steel selection for pipelines may vary depending on factors such as the operating conditions, transportation medium, and regulatory requirements. Other grades like API 5L X60, X65, and X70, as well as other standards like ASTM A53 and ASTM A106, may also be used based on project specifications and regional standards.