Validation of procedures for fatigue life assessment of a steel pressure vessel

Abstract

ABSTRACTA full‐size pressure vessel, made of steel plate P355NL1 (EN 10028‐3), was tested under repeated internal pressure until its failure was observed. Also, four representative structural details of the tested pressure vessel were fatigue tested under load control with a stress ratio of R= 0. These structural details are basically two seam‐welded joints, namely a butt‐welded joint and a joggle‐welded joint, one plate attachment using fillet‐welded joints and a nozzle‐to‐plate connection. S–N curves were generated for these details based on both nominal and structural stresses. These curves are critically compared with those proposed in pressure vessel design codes like the ASME VIII – Division 2, the PD 5500 and the recently approved EN procedures, the EN 13445 standard. Finally, predictions of the fatigue life of the pressure vessel, obtained using the previously referred procedures and the experimentally derived design curves are critically compared with the observed life of the vessel.