Design And Analysis Of Marine Drilling Riser Connection Unit

Marine oil and gas resource accounts for about45%of the earth’s resources, as the basisof deep water oil and gas resources exploration and development, the construction of majorequipment has been included in national Marine development planning. Though “OffshoreOil981” had drilled in the South China sea, the riser relevant equipment still need to rely onimports, therefore, we need to speed up design of petroleum equipment research anddevelopment to achieve the real localization of offshore oil drilling equipment. Thisdissertation is supported by the National Major Science and Technology Project “Research onDeepwater Drilling Riser Operation Management and Safety Evaluation Technology”.According to the harsh environment of South China Sea, systematic study on drilling riserconnecting unit technology was conducted. The research covers some hot issues of drillingriser connecting unit, such as design of riser system connection unitvirtual prototype, keyparts design analysis, link unit seal performance analysis and riser system reliability analysis.The research findings provide effective technical supports for design and manufacture of risersystem connection unit.1Design of riser connection unit virtual prototypeThrough research at home and abroad riser connection unit manufacturers products andrelated patents, analyse the riser slip-joint, flex joint, riser connector and hydraulic connectorfunction principle, the locking structure and sealing of riser slip-joint and different types offlex joint and riser connector. Design the virtual prototype of riser connection unit with Pro/Esoftware and aim to provide guidance for the design of riser connection unit.2Design and analysis of riser connection unit’s key componentsThe riser connection unit design criterion was proposed through studying API standardsrelated to the riser. Optimization design and analysis of riser connection unit key components,especially for the riser circlip of fast connector and flexible joints elastomer, was done withhelp of ABAQUS software. Through the analysis, design method for the main dimensionparameters of fast connector circlip was established and the influence for stiffnesscharacteristics of flexjoint elastomer induced by rubber parameters change can providetheoretical support for the relevant parts design.3Seal performance analysis of riser connection unitAs core element of riser connection element design analysis, sealing performanceanalysis is vital to the security of the riser system. the seal checking criterion was establishedby researching existing riser connection unit sealing structure and drilling accidents caused by riser seal failure. Theoretical support for riser connection seal selection was provided bycomparing the sealing performance of o-ring seal and its evolution form. slip-joint sealingperformance was analysed, and the corresponding measures to enhance the reliability ofsealing was proposed.4Reliability analysis of the riser connected systemHarsh environmental conditions request high reliability of the riser connection system,research of the riser connection system failure mechanism was conducted by establishing riserconnection failure Petri net model with Timenet4.0software. Riser connection system failurequalitative analysis was completed, and the corresponding measures to enhance the reliabilityof riser connection system was put forward. In addition, an optimization modle based on theexpectancy criteria was established and analysis and optimization of riser single pressuretesting unit was completed. Reliability Assurance Approach for riser system was proposedand HAZOP analysis for lower riser was done. The results make a guidance to improve theriser systems reliability from the design, manufacture, transport and installation.