Design And Research On Subsea Production Valve And Its Actuator Of All Electric X'mas Tree

According to the data,the potential crude oil reserves in the deep water region are as high as 100 billion barrels,making its an important succedded area of global oil and gas reserves.Therefore,the research and development of abundant marine oil and gas resources has become the priority for our human.As an important component of subsea production system,subsea Christmas tree plays a role in controlling oil production,connecting borehole and production pipe and monitoring production data.In recent years,the all-electric Christmas tree system produced by Cameron has been successfully run in the Gulf of Mexico.Compared with the hydraulic system Christmas tree,the all-electric system has a compact structure and good operation performance,which can realize real-time feedback and zero discharge.However,the all-electric Christmas tree technology in china is still in primary stage,so the study of all-electric Christmas tree will help to break the technology blockade,which is of great significance.This paper summarized the design standards and criteria,working environment and performance parameters,function and action requirements,size and weight requirements of all-electric subsea Christmas tree.The overall design scheme of all-electric production gate valve then has been determined.The paper selected the valve materiel under 10000 psi working pressure and EE working environment.The paper also finished the design and corresponding assembly drawing.of the valve body,valve cover,gate plate,valve stem,connecting flange,sealing seats and stuffing box.The parts material was also selectedThis paper designed all sealing structures and studied their sealing performance.The metal-to-metal and elastic-to-metal sealing mechanism were analyzed respectively under69 MPa working pressure and 15 MPa marine pressure.The non-linear contact model between the elastic and metal material were established by ABAQUS finite element analysis software.The paper compared different influences of mechanical properties,working pressure,and initial preloads on sealing performance.Then gained the best preload condition.The paper designed a subsea valve electric actuator.Studied and summarized the function program,action parameters and weight requirements of subsea electric actuator.Outlet pressure variation was calculated by FLUENT software when gate was in different positions during opening operation.The maximum opening force and closing force were calculated respectively.Compared advantages and disadvantages of different “fail-safe”schemes.Calculated the minimum spring pre-load that required to help valve to close under fail conditions.