Prediction and evaluation of residual life of casing with corrosion defects

Abstract

ObjectiveAs oil field development progresses into the middle and later stages, casing damage becomes increasingly severe, particularly incidents such as leakage, reduction in diameter, bending, and fractures caused by corrosion defects, leading to unsafe operations. Therefore, there is an urgent need to conduct residual life and safety evaluations of old oil field casings.MethodsBased on the von Mises equivalent stress yield criterion, a three-dimensional finite element calculation model of casings containing corrosion defects was established to analyze the influence law of corrosion pit depth and angle on casing stress distribution. The particle swarm optimization-gaussian process regression （PSO-GPR) algorithm was employed to construct a predictive model for casing corrosion rates.ResultsIntegration of the two models, the evaluation of the residual life of casings with corrosion defects was completed, it has theoretical guidance significance for the prevention and management of corroded casings in oil field operations.

Keywords

• Casing corrosion defect
• Finite element analysis
• PSO-GPR
• Corrosion rate
• Residual life