Residual Stress Distribution in Welded Steel Pipes and Its Impact on Performance

Residual stress is an important factor affecting the mechanical properties and service life of welded pipes. It arises due to non-uniform heating and cooling during the welding process. Key aspects include:

• Longitudinal Residual Stress: Can lead to cracking or warping in high-pressure applications.

• Circumferential Stress: Influences fatigue resistance, especially in pipelines subjected to cyclic loads.

• Post-Weld Heat Treatment (PWHT): Used to relieve residual stress, enhancing the ductility and toughness of the welded joint.
  Understanding and controlling residual stress is crucial in industries such as nuclear power, aerospace, and deep-sea oil transportation.