A commercial heat exchanger system suffered a catastrophic failure shortly after returning to service after dormant period of several years. 

Engineers from MME identified the heat exchanger failure mechanism as cracking of the stainless steel tubes.  Metallurgical failure analysis identified stress corrosion cracking of the tubes due to the presence of chlorides to be the cause of failure.

Additional investigation identified poor cleaning practices prior to the dormant storage period to be responsible for chloride contamination.