Pre and post-weld heat treatment (PWHT) are essential processes in the field of welding, particularly in industries where the structural integrity and performance of welded components are critical. These heat treatment processes involve controlled heating and cooling of the material before and after welding to relieve residual stresses, reduce the risk of weld-related defects, and improve the overall properties of the welded joint.
The primary purpose of preheating is to raise the temperature of the base metal in the vicinity of the weld before the welding process. This helps to reduce the risk of cracking, especially in high-stress areas or when welding thick sections.
Post-weld heat treatment is applied after the welding process to relieve residual stresses, improve mechanical properties, and ensure that the welded joint meets the required specifications and quality standards.
