Deep Sea Oil And Gas Pipeline Flange Connection System And Prototype Experimental Study

With China’s growing demand for oil resources and the difficulty of substantial increaseof onshore oil and gas resource,the development of marine oil and gas resources has becomean important strategy to ensure our energy security. Subsea oil and gas pipeline is animportant part of offshore oilfield subsea production system,in order to meet the need ofoffshore oil development,the laying scale of subsea pipeline will further increase. Subseapipeline underwater connection technology is an important part of the pipeline layingtechnology,which can be used to develop marginal oilfields,deepwater fields and mainten ofunderwater production pipeline. Among underwater connection technology,the bolt flangeconnection is a kind of widely used and effective way of connection, divers can not reach thedeepwater area,so it only can be done by automatic flange connection system,at present Chinadoesn’t have related products used in practical engineering,so research on its key technologyhas important practical significance to promote the localization of the system.This project comes from the sub-topics of the Eleventh Five-Year national "863" majorprojects "deepwater pipeline laying technology",which is "deepwater subsea pipelineunderwater tie-ins technology and AUT inspection equipment localization technologyresearch ". In this paper,the domestic and foreign development situation of subsea pipelineunderwater connection method and pipe flange connection system are reviewed,andcorrelation technology involved in the design of the flange connection system is introduced.Learning from design experience of foreign related products and combining with the actualconditions,overall technical scheme of the flange connection system is designed whichincludes pipeline rough adjustment H frame,pipeline connection tool and flange connectiontool three functional modules,its operating process is analyzed,its virtual prototype and thehydraulic servo control system of the axial force and alignment tool and flange connectiontool are studied.First of all,in accordance with the clamping device of the axial force and alignment toolneed appropriate clamping force problem during the work process of pipeline connectiontool,in this article,the force of clamping mechanism and its structure parameters’ influenceon strength of pipeline are analyzed,strength calculation formula of pipeline is deduced,clamping mechanism optimization mathematical model is established and its single objective and multi-objective optimization design are done based on an improved particle swarmalgorithm.Secondly, aimming at the problem of20nut introduced mechanism motor highersynchronization control precision of the flange connection tool nut magazine,through theanalysis of several commonly used closed loop synchronous control strategy,multiple motoradjacent cross coupling synchronization control scheme based on the least relevant axiscontrol thought is determined,a single channel mathematical model of valve-controlled motorposition servo system is built,and simulation is done on four motor synchronization system asan example based on sliding mode control method with new exponential reaching law,thesynchronization control performance is verified.Again,according to the engineering requirement that each bolt should has appropriateand equal preload in bolt flange connection structure,in this paper,comparative analysis isdone on the commonly used three kinds of preload calculation method,the U.S ASME newspecification is used for computing flange connecting bolt preload needed, the process of boltpreload is simulated by adopting the method of finite element and elastic coefficient ofcorrelation,the preloaded scheme that one round and two rounds which improving boltpreload is given,and experimental study of the prototype is carried.Finally,experiment platform of the flange connection tool is established in the paper,the flange connection tool system debugging experiment and multiple motors synchronizationcontrol experiment are done,and pipeline flange onshore connection test is carried by usingpipeline chassis to simulate the H frame.