Stiffener as a special design solution for pressure vessel repair

The reparation of vessel 970 is shown, since the risk is very high (close to the worst case of both probability and consequence, being the highest). Since the defect location was not suitable for digging out and repair welding, it was decided to make a circumferential stiffener, to reduce the stress acting on the welded joint, so that both the stress intensity factor and net stress are reduced significantly.