A time-variant corrosion wastage model for subsea gas pipelines

Accurately assessing the reliability of ageing structures is essential, especially in the oil and gas industry where inaccurate predictions of structural performance may have significant hazardous consequences. This study aims to develop a time-dependent pit depth corrosion model for subsea gas pipelines. This model is formulated with the parameters as function of age using the 3-parameter Weibull distribution function. The developed model gives the prediction of the pit depth of a gas pipeline at any given age by changing the scale, shape and location parameters. Measurement data for gas pipeline corrosion pit depth were collected and the statistical characteristics were quantified by statistical analysis in terms of gas pipeline age. The results and outcomes of the present study will be useful for predicting the corrosion pit depth of gas pipeline structures and can be used in the design stage of a new gas pipeline structure.