Failure Probability Based Analysis of Dropped Object on Submarine Pipelines

One of the safest and the most economical methods to transform oil and gas is pipeline system. Prediction and prevention of pipeline failures during its assessed lifecycle has considerable importance from industrial experiences point of view. The dropped object is one of the accidental scenarios in the failure of the submarine pipelines. In this paper, the influence of the dropped object on a submarine pipeline located in near platform of 19C South Pars gas field and having 32” diameter is considered as a case study. According to the DNV-RP-F107- the probability of failure analysis of the pipeline due to a dropped object- firstly, the impact frequency is calculated. Secondly, the probability of damage due to box-shaped object is determined by using energy transfer analysis and Monte Carlo method. Annual frequency of failure of the pipeline is equal to 4.5×10-7 that is less than the rule-based acceptance criteria of 10-5. In other words, this level of protection is safe for the pipeline.