The purpose of stress relief heat treatment is to reduce inner tension within the workpiece that arise from irreguar cooling, which originate from welding for instance. We conduct the process of stress relief for pressure vessels and pipes in a chain glow system or annealing furnace.
According to valid regualtions
VdTÜV material sheets (451-82/1)
AD information sheet HP 7/1
ASME Code Section I
ASME Code Section VIII Div. I