Analysis Of Submarine Pipeline Designing

In recent years, submarine pipelines are the most popular way to translate oil andgas for its safety and economy. There are many steps in pipeline designing andconstruction. This dissertation mainly includes four parts: the riser, pipeline lifting,laying analysis, and trenching. Associating with real projects, allowable stresseschecking, and things to be considered during construction are given. Through analysison calculating model, process and output, make some suggestions on submarinepipeline designing course. At the end, compare different stress formula of differentregulations and give out how to chose pipeline thickness.The main parts of this paper are shown as follow:1. Definition and constitutes of riser system. Analyze different loadingconditions, pipe data, circumstance data, plat form movement and free span.Use 'autopipe' program to calculate pipeline stress.2. Calculate pipeline lifting bend moment, effective axial force, and outsidepressure for the most unfavorable combination of loads, and check theallowable stress contrasting with DnV1981. Using 'riser' and 'suspend'program.3. Analyze pipeline static force during laying procedure referring to differentwater depth. Check laying bend moment, effective axial force, outsidepressure for the most unfavorable combination of loads using 'offpipe'program.4. Construct trenching calculation model, and give a calculating result of a realproject.5. Compare stress formulas of DnV with formulas of ASME, then give a way tochoose pipe thickness.