Fatigue Life Prediction for Flexible joint of Deepwater Riser in Liwan Gasfield of the South China Sea

摘要

The paper introduces operating process of fatigue life prediction forrnflexible joint of deepwater riser in Liwan gas-field, the South China Sea.rnTo solve the key technical problems of deepwater risers in LiWan3-1rngas field development, Learning from the advantages and foreignrnexperience of high temperature high pressure flexible joints (HTHPFJ),rnstudying the loading of flexible joints, establishing a model about thernriser and the flexible joint as a whole, and time-domain dynamicrnanalysis of the model using the professional maturity ocean pipelinerncalculation software according to the actual environment characteristicrnof LiWan3-1, extracting the time-domain response spectrum from therntop of the riser as the loading of the nonlinear analysis. Then the fatiguernlife prediction is made based on the nonlinear dynamic analysis. Finally,rnthe shortest life of the HTHPFJ is 15 years from the stress pattern of thernfatigue life which meets the fatigue service life.