Seo Jung Kwan, Cui Yushi, Mohd Hairil Mohd, Ha Yeon Chul, Kim Bong Ju, Paik Jeom Kee. A risk-based inspection planning method for corroded subsea pipelines

Ocean Engineering 109 (2015). — p. 539–552.Risk assessment procedures for subsea projects are a key component of design and maintenance and inspection efforts, as resulting operating time may cause aging damages to adjacent subsea equipment. In particular, for subsea pipeline management work, corrosion of pipelines may impinge on a vast number of subsea pipeline systems and can result in significant environmental and financial risks, unless the appropriate management methodologies are implemented. Hence, this paper presents risk based on probability of failure (PoF) and consequence of failure (CoF) estimation of a time-variant corrosion model and burst strength for the corroded oil pipelines. The probability of corrosion defect is calculated as PoF, which is a time-variant model from measured data in the subsea industry and CoF is considered as the burst strength of corroded pipelines. Pipeline consequence modelling is performed using regulation design codes to simulate the pipeline strength and calculate the probability. The proposed methodology offers a standardised procedure for incorporating both design and inspection/maintenance planning aspects of pipeline systems, thereby providing a more systematic, comprehensive procedure for risk-based inspection than previously available.