Line pipes are essential in transporting oil, gas, and other fluids. They are categorized by various specifications and grades that indicate their mechanical properties and applications. Here are some common grades of line pipe:

API 5L Grades:

Grade A: Suitable for low-pressure service and has a minimum yield strength of 245 MPa.

Grade B: Commonly used in the oil and gas industry with a minimum yield strength of 345 MPa.

X Grades (e.g., X42, X52, X60, X70, X80): These grades indicate increasing yield strength, with X42 having a minimum yield strength of 290 MPa and X80 reaching up to 620 MPa.

ASTM A53:

Grade A: Suitable for mechanical and pressure applications, with a minimum yield strength of 205 MPa.

Grade B: A stronger option with a minimum yield strength of 240 MPa, commonly used for welded and seamless pipes.

ASTM A106:

Grade B: Used for high-temperature service, with a minimum yield strength of 240 MPa.

Grade C: A higher strength option, with a minimum yield strength of 260 MPa.

Other Specifications:

ASTM A333: Low-temperature service pipe, with various grades suitable for temperatures down to -101 °C.

ISO 3183: This specification includes various grades, often used for offshore applications, aligning with API 5L specifications.

Each of these grades has specific applications based on their mechanical properties, which are essential for ensuring the safety and reliability of pipeline systems. For further details, you can refer to the relevant specifications or industry guidelines.