Research On The Failure Mechanism And Improvement Of The Seal Of The Oscillating Pup Joint Of The Hydraulic Oscillator

As the main oilfields in China gradually into the late development,and to high temperature,high pressure and complicated deep stratum development,so directional well and horizontal well drilling technology has become an important link in the oil and gas exploration and development,in order to enhance the extension ability of directional wells,achieve maximum reservoir productivity efficiency increase,reduce drilling torque and drag problem the problem has become the focus of research in the world in the field of drilling,but now the drag reduction tool has some defects and failure of seal leakage,replacement and maintenance difficult,high labor intensity,to design more reliable sealing performance,short oscillations of longer life,aiming at the hydraulic oscillator short field use the existing sealing structure are relatively easy the early failure phenomena,the key of hydraulic oscillator short sealing parts failure mechanism is analyzed,on the basis of ABAQUS and other software are used to simulate the static seal and dynamic seal of the vulnerable parts,and the improvement measures are put forward.Combined with the failure analysis results,a new composite rubber seal structure is designed,and its action seal analysis and static seal analysis are carried out.Finally,a new design of the expansion expandable-up spring structure is put forward,and the dynamic simulation is carried out.The research results provide a reference for the operation safety of the hydraulic oscillator,thus providing an important guiding significance for improving the application of the hydraulic oscillator to reduce the friction and drag reduction function.The main contents of this paper are the following aspects:In the collection of domestic and foreign research status of main components of short oscillating sealing on the basis of the analysis of the basic structure,working mechanism and the problems existing in the use of short circuit oscillation sealing parts mainly,combined with the 165 type hydraulic oscillator used in the field of downhole vibration study on short contact main sealing parts the actual proposed specific research program the short circuit simulation main sealing oscillation behavior of components.Based on the mechanical analysis of static and dynamic working process of the main seal components of underground oscillation,a 3D solid model of oscillating short sealing main parts of hydraulic oscillator is established by using modern mechanical analysis software of SolidWorks.By using the principle of contact problems of linear and nonlinear finite element method,combined with the working mechanism of short circuit oscillation main sealing parts and structure characteristics,established the finite element oscillation short main sealing parts static and dynamic analysis of the process simulation model and behavior model,a more accurate simulation of the working process of the main oscillation short sealing parts.In short the main oscillation seals rubber and nonlinear large deformation of expandable-up spring force in the movement and the state,the deformation characteristics and the moving rules directly reflects the oscillation of static and moving short main sealing parts process,found the main sealing parts of short circuit oscillation in different working conditions,the rules and conditions of stress and contact pressure of rubber seal and expandable-up spring seal,and provides a theoretical basis for the analysis of rubber sealing performance and expandable-up spring.Compared with the original seal structure and composite seal structure of the oscillating short joint,the finite element simulation was carried out,and the results were compared and studied.It shows that the sealing effect of the seal groove and the transmission shaft is good in the static seal,but it is easy to fail early in the dent.It indicates that during the process of reciprocating transportation,the dynamic friction between metal and metal will happen in the dynamic seal.During the transient,it will form overheating,resulting in the hot contact between the transmission shaft and the inner cylinder,resulting in adhesive wear.Therefore,it is easy to fail early.A comparison of structural oscillation short connection area of the piston position of the original rubber sealing structure and expandable-up spring seals were simulated,and the results were compared,the simulation research of statics and kinematics of different materials of expandable-up spring,show that the elastic modulus of expandable-up spring is smaller,the greater the deformation,the stress within the allowable range,and the seal rubber sealing structure is better than the rising expandable-up spring structure,no adhesive wear and early failure.This paper based on the hydraulic oscillator short circuit based sealing part statics,kinematics simulation analysis,using the method of geometric and material nonlinear contact problem of a finite element analysis of the sealing structure of hydraulic oscillator model and simulation model,the performance parameters of main parts of hydraulic oscillator in static seal and reciprocating seal were calculated for the analysis of the existing hydraulic oscillator,short circuit provides new theory and method of sealing performance of the structure and design of hydraulic oscillator model,the theoretical research to further improve the level of the hydraulic oscillator,reduce accidents,improve the development efficiency of oil and gas exploration,has very important significance to reduce the cost of production.