Failure Analysis of 316L Air Cooler Stainless Steel Tube in a Natural Gas Production Field

摘要

In spite of the excellent resistance of stainless steel (SS) towards uniform corrosion, overcomingvarious localized corrosion could be a real challenge. This work presents an analysis of the failurebehavior of 316L SS air chiller tube with a peripheral crack used in a Qatari gas company in Qatar.Macroscopic failure characteristics were analyzed by means of visual inspection, digital imaging whilelight microscopy, electron microscopy (SEM / EDX), and X-ray fluorescence (XRF) were employedfor microstructural and fractographic characterization. The results indicate that the failure phenomenon-that was primarily initiated by Cl led to an eventual autocatalytic pitting corrosion. The failure reasonsof the tube are related to the combined effect of constant and cyclic external stresses, as well asinternal residual stress originated from various operating conditions.