The Structure Of The Subway Station Is Made Of LSAW Steel Pipes API 5L X65 PSL2

API 5L X65 PSL2 provides a minimum yield strength of 450 MPa and tensile strength typically ranging from 535 to 760 MPa, offering excellent load-bearing performance for large-span underground structures. PSL2 requires stricter control of chemical composition and carbon equivalent, generally limiting P and S to ≤0.025% to enhance weldability and fracture resistance. Mandatory impact testing ensures adequate toughness, often achieving specified energy values at low temperatures, which is critical for safety in confined underground environments.

Huayang manufactures X65 pipes using controlled forming and double-sided submerged arc welding to maintain uniform wall thickness and seam integrity. Each pipe undergoes 100% ultrasonic inspection, hydrostatic testing, and mechanical verification in compliance with API 5L PSL2. Strict tolerance control on straightness and ovality supports precise assembly in structural frameworks, ensuring long-term stability and reliability in subway station construction projects.