Study On Disconnection Technique For Storm-safe Drilling Riser

The storm-safe drilling riser has advantages of saving time, good economic benefit,simple structure and wide application. This dissertation is supported by the National MajorScience and Technology Project “Research on Deepwater Drilling Riser OperationManagement and Safety Evaluation Technology”(2011ZX05026-001-05) and thefundamental research funds for central universities of the study “Research on the keytechnology of storm-safe drilling riser in South China Sea”(12CX06065A). The disconnecttechnology of storm-safe drilling riser has been studied, on the condition of high frequencytyphoon and referring the NSDP structure abroad. The main contents are as follows:(1) The storm-safe drilling riser system has been researched. The method of determinethe install position of NSDP was submitted, and the scheme of EDS was set in the same time.The function principle analysis of NSDP was taken out, determining the design parametersand then designing the two dimensional drawings by AUTO/CAD. Based on the2D drawings,3D digital prototype of NSDP was created.(2) The structure strength of NSDP playing an important role in the safety of storm-safedrilling riser, and its design performance must be evaluated. Based on finite element analysissoftware ABAQUS, NSDP strength analysis has been done. Under200million pounds ofaxial force, the stress NSDP have been obtained by stress linearization in different path,evaluating its bearing capacity.(3) Based on the design structure of NSDP and riser configuration of deepwater platform,the model of1500m storm-safe drilling riser system was established in ABAQUS. Accordingto the environmental conditions in South China Sea, static analysis of storm-safe drilling riserhas been done, obtaining the axial force, bending moment, deformation and equivalent stress.According to the limit criterion, the operation window was obtained.