Study On The Remaining Strength Evaluation Of Corroded Submarine Pipelines

With the development of economy and ocean project in recently years,many countries play more and more importance on the exploitation of oceanoil. As an important means of transporting oil under water, submarinepipeline is subjected to corrosion caused by surrounding water and the oiltransported in the pipeline inevitably.It is well concerned about how tocontrol corrosion and how to estimate the remaining strength of pressurizedpipelines contained active corrosion, which is also very important toensure the safety and reliability of pipelines. Whether the method toestimate the remaining strength of pipelines or not is very important tothe remaining life, mending and pipeline replacement, which is also theprecondition for a pipeline manager to make decision efficiently.The paper is based on the rupture-dynamical theory and DNV RP-F101recommendatory method, through the study of three corrosion models, we havebuilt up rational estimation model, adopted subentry safety coefficientmethod and allowed stress method to estimate the remaining strength ofcorrodent pipelines, and finally, introduced the Genetic Algorithms methodto compute the reliability of corrodent pipelines, gaining the reliabilityindex, and provided corresponding program. Through some examples, it isproved sound and the program's veracity.