A failure in one of the de-salter relief lines of the crude distillation unit. This paper describes the probable causes and the adopted remedies for the localized corrosion observed in the insulated relief line. Circumstantial evidence and failure morphology were used in arriving at the root cause for this failure.
A 22-year-old liquid line experienced an unexpected failure due to internal corrosion after adding the production from one well. Investigation included ILI records, operating pressures and temperatures, oil pressure / volume / temperature (PVT) data, possible flow regimes, failure analysis reports, and mitigation practices.