Research On Metal Sealing Performance Of Downhole Flow Control Valve

In recent years,China petroleum industry has gradually entered the stage of oil and gas scarcity.It is difficult to exploit land oil,and the reservoir exploitation has been transformed into a harsh environment where the exploitation of deep seas,beaches and deserts is difficult.This has caused the difficulty in oil and gas production and the cost of production.The huge challenge,mining environment and technical problems have seriously hindered oil and gas recovery.How to optimize the economic value of oil and gas resources while improving the mining rate,the research and development of intelligent completion systems and related technologies provide solutions to this problem.The core of the intelligent completion system is the downhole flow control valve,and the sealing device in the flow control valve is the most important.The metal seals in conventional the axial direction.This article uses a radiaflow control valves are in the form of face seals that require a force to maintain a seal from l seal form that requires only oil pressure to actuate the seal ring to form a seal.In this paper,the stress of the metal sealing ring is theoretically analyzed.A kind of inclined beam metal sealing structure is proposed.The mechanical model is simplified into a combined model of the cylinder interference fit and the cantilever beam force.The stress of the inclined beam model sealing contact surface is obtained.A formula that calculates the stress of a similar model.The hollow O-shaped metal sealing ring and the U-shaped metal sealing ring are improved,and the end face sealing form is improved into a radial sealing.Based on the inclined beam model,a V-shaped metal sealing ring is designed.The parameters of the three kinds of sealing rings were analyzed by ABAQUS software.The simulation results and the actual situation were compared.The K-shaped sealing ring was selected as the sealing scheme.By improving the sealing contact surface of the K-shaped metal sealing ring,it relies on the contact bevel to abut against the flow sleeve to complete the sealing.Considering the error between the ideal model and the actual component,the seal ring with the roundness error is simplified to rotate with the K-ring as the cross-section,and the circumferential path is the ellipse with the long-short axis difference as the roundness tolerance.Analyze the roundness tolerance value.For the effect of the K-ring sealing performance,it is concluded that the roundness error will affect the performance of the sealing ring.A set of sealing test devices is designed for the metal sealing structure of the flow control valve.The test bench is mainly composed of three parts:pressure vessel,hydraulic control system and electronic control system.It simulates the working environment of high temperature and high pressure in the underground and checks the sealing performance of the sealing ring.