Post weld heat treatment

Post Weld Heat Treatment (PWHT) is a process used in welding and metal fabrication to improve the mechanical properties of welded joints. It involves heating a welded assembly to a specific temperature and then allowing it to cool under controlled conditions. The primary purposes of PWHT include: 1. **Relieving Residual Stresses**: Welding can introduce internal stresses in the material due to thermal expansion and contraction. PWHT helps to reduce these residual stresses, which can lead to improved fatigue resistance and durability.