The macromorphology, material properties and corrosion products composition of the corrosive perforated P110 tubing in a water injection well were characterized. Combined with the investigation of service conditions and tubing neutral point calculation, the reason of external corrosion perforation in the water injection well was analyzed. Results showed that the obvious localized corrosion morphology only appeared on the corrosion perforation P110 tubing among the whole well depth tubing, more specifically, the failed tubing’s corrosion morphology was ulcerative. Meanwhile the failed tubing was under the tubing’s neutral point and in sinusoidal buckling. The material properties of the perforated tubing met the requirements of P110 steel in API SPEC 5CT-2011. The tubing external corrosion products were mainly FeOOH and CaCO3. It was indicated that in the buckling state, P110 tubing and casing contacted to form a gap, and then crevice corrosion failure occurred. The corrosion type was oxygen absorption corrosion, and the main factors of corrosion were gap effect and dissolved oxygen content. The corrosion mechanism was the acidification autocatalytic effect of occluded corrosion cell.
