Leakage of an austenitic steel CO2 storage tank

Abstract

After the occurrence of water droplets on the manhole outer wall of a storage tank for carbon dioxide, by detailed inspection, a net of cracks is detected in the manhole flange, close to the welded joint between the flange and manhole mantle. Since the droplets are found on the outer side, it is concluded that the through cracks are in question. The analysis of the number and the size of cracks, form and dimensions of manhole cracked segment, the properties of the applied material and stress state has lead to the conclusion that operational safety of the tank is endangered. In order to solve the problem, the damaged zone had to be eliminated and the shape of the manhole neck needed to be redesigned. After performed repairs, the storage tank could be put into operation again.

Posle pojave vodenih kapi na spoljašnjem zidu otvora za reviziju posude za skladištenje ugljen dioksida, detaljnom inspekcijom je otkrivena mreža prslina na prirubnici revizionog otvora, blizu zavarenog spoja između prirubnice i zida revizionog otvora. Pošto su kapljice uočene na spoljašnjoj strani, zaključuje se da su u pitanju prolazne prsline. Analizom broja i veličine prslina, oblika i dimenzija segmenta naprslog revizionog otvora, osobina primenjenog materijala i naponskog stanja, su doveli do zaključka da je radna sigurnost posude u opasnosti. Da bi se rešio ovaj problem, oštećena zona je morala da se ukloni, a oblik vrata revizionog otvora je morao da se rekonstruiše. Nakon obavljenih popravki, posuda za skladištenje je ponovo puštena u rad.