What does stress relieving in piping primarily aim to reduce?

Stress relieving in piping primarily aims to reduce weld residual stresses. When metal is welded, the rapid heating and cooling cycles can create internal stresses within the material due to uneven expansion and contraction. These residual stresses can lead to issues such as cracking, distortion, or reduced fatigue resistance of the welded joint. Stress relieving is a heat treatment process that involves heating the welded component to a specific temperature and then allowing it to cool slowly, thereby reducing these residual stresses and improving the structural integrity of the piping system.

The focus on weld residual stresses is critical in applications where the integrity of the system under load is essential, such as in pressure vessels and pipelines. By effectively managing these stresses through proper heat treatment, the overall reliability and safety of the piping can be enhanced.