What is API 5L X70 PSL2 specification?

API 5L X70 PSL2 is a high-strength, low-alloy (HSLA) Steel pipe specification developed by the American Petroleum Institute (API). It is commonly used in the pipeline industry for transporting oil, gas, and other fluids. The "X70" designation indicates the minimum yield strength of 70,000 psi, and "PSL2" refers to Product Specification Level 2, which includes more stringent chemical, mechanical, and testing requirements than PSL1. Here are the key details about API 5L X70 PSL2:

Chemical Composition

Carbon (C): ≤ 0.24%

Manganese (Mn): 1.10-1.60%

Phosphorus (P): ≤ 0.025%

Sulfur (S): ≤ 0.015%

Silicon (Si): ≤ 0.45%

Vanadium (V): ≤ 0.10%

Niobium (Nb): ≤ 0.05%

Titanium (Ti): ≤ 0.04%

Other alloying elements: Chromium (Cr), Nickel (Ni), Molybdenum (Mo), Copper (Cu), and others may be present in small quantities.

Mechanical Properties

Yield Strength (YS): ≥ 485 MPa (70,000 psi)

Tensile Strength (TS): 570-760 MPa (82,000-110,000 psi)

Elongation: Depends on the diameter and thickness of the pipe, but generally around 18-20%

Charpy V-Notch Impact Test: Required, with specific values depending on temperature and test location (e.g., weld seam, HAZ, base metal).

Manufacturing Processes

Seamless (SMLS) Pipe

High Frequency Welded (HFW) Pipe

Double Submerged Arc Welded (DSAW) Pipe

Testing Requirements

PSL2 pipes have more stringent testing requirements than PSL1, which typically include:

Chemical Composition Analysis: Ensuring the correct balance of alloying elements.

Mechanical Testing: Tensile tests, impact tests, and hardness tests.

Non-Destructive Testing (NDT): Ultrasonic testing, radiographic testing, and hydrostatic testing to detect any defects.

Dimensional Inspection: Checking the pipe’s diameter, wall thickness, length, and straightness.

Surface Inspection: Ensuring no surface defects such as cracks or dents.

Applications

API 5L X70 PSL2 pipes are used in various applications due to their high strength, toughness, and resistance to environmental conditions:

Oil and Gas Transportation: Mainline pipelines, gathering systems, and distribution systems.

Offshore Pipeline Systems: Submarine pipelines, risers, and flowlines.

Onshore Pipeline Systems: Transmission lines, gathering systems, and distribution networks.

Structural Applications: Supporting frameworks for offshore platforms and other structures requiring high strength and durability.

Summary

API 5L X70 PSL2 is a highly robust and reliable steel pipe specification used extensively in the oil and gas industry for high-pressure and high-strength applications. Its enhanced chemical and mechanical properties, coupled with rigorous testing requirements, ensure superior performance and safety in demanding environments.

Email: [email protected]

Whatsapp(WeChat): +86 17337172584