Stress Relief Annealing of Welded Assemblies

When stress-relief annealing, you heat the component below the transformation temperature so that the internal stresses from welding can settle – the structure remains unchanged. If you don't do it cleanly or don't hold the temperature long enough, the stress stays in the material and the part can crack or distort. In practice, this means: heat evenly and controlled, not too hot, and hold the temperature until the stress is out. How long exactly depends on the material and wall thickness – you have to go by feel and experience.