Failure analysis of welded 0Cr13Al tube bundle in a heat exchanger

The cracking of 0Cr13Al stainless steel tube bundle in condensate/heavy gas oil (HGO) heat exchanger in a petrochemical plant was studied to investigate the failure mechanism. The chemical composition, elements distribution and the morphology of the cracks were analyzed. The results showed that intergranular stress corrosion cracking (ISCC) was the main reason for this failure, and welding microfissures promoted the failure. Strict welding processes, and materials that are not susceptible to intergranular cracking, such as TP321 stainless steel, are suggested to avoid such failures in future application.