Design And Analysis Of Intelligent Sliding Sleeve Structure Based On RFID Communication

Shale gas has become a new direction of energy development in China,and will also play an important role in China's future energy.Multistage fracture stimulation of horizontal well is the most widely used method for shale gas reservoir transformation,and it also accounts for a larger proportion of investment in shale gas development.Bridge plug perforation fracturing technology and multi pitch sliding sleeve fracturing technology is the horizontal well multistage fracturing techniques commonly used,but there are complex processes,fracturing series restrictions and other shortcomings,it is difficult to meet the requirements of new fracturing technology.Aiming at the existing shortcomings of fracturing technology in China,this paper designs a kind of intelligent sliding sleeve based on RFID communication,after researching the current situation of the research on stepless slip sleeve at home and abroad.The sliding sleeve adopts RFID technology as the communication mode,the fracturing pulse communication is used as the auxiliary communication mode,and the hollow shaft motor is used as the power source.The joint seal of dynamic seal and signal transmission in intelligent slip sleeve is studied in detail.The intelligent sliding sleeve can realize full bore and infinite series fracturing.The sliding sleeve opening can be adjusted continuously and the fracturing process is simple the process is simple,and it overcome the shortcomings of the existing technology.The specific contents of this paper include the following aspects:(1)In this paper,after researching on the current situation of the research on the stepless slip sleeve at home and abroad,Two kinds of intelligent sliding sleeve are designed,which are pressure pulse control-hydraulic drive and RFID communication control-motor drive.The two schemes are compared,and the sliding sleeve of RFID communication control-motor drive is selected as the final design scheme.The fracturing technological process is designed.(2)The mechanism of elastic seal is analyzed,a low friction and corrosion resistant C-shape slip ring seal ring is used as the sealing ring for the sliding sleeve dynamic seal.Mechanical property parameters test and friction coefficient measurement of C shape slip ring seal ring were carried out through experiments.Based on the measured parameters,the relationship between the sealing force,compression rate and temperature and the sealing performance and friction is analyzed by the finite element method.Through analysis,when the pressure is 0-70MPa and the temperature is 20-120 ?,it is found that the greater the compression ratio,the better the sealing capacity.As the temperature rises,the sealing ring expands and the sealing capacity is enhanced.C slip ring has the characteristics of equal friction between inside and outside stroke,and with the increase of temperature,compression ratio and sealing pressure,the friction force increases,and the higher the compression ratio,the greater the influence of temperature on the friction force.For dynamic sealing,the smaller the better the compression rate,can reduce the sliding friction.When the sealing pressure reaches 70MPa,in order to ensure the reliability of the seal,the seal compression rate should not be less than 15.6%.(3)In order to realize the control of the communication signal from the high pressure chamber to the pressure chamber,the signal transmission joint is designed and the sealing mechanism of the signal transmission joint is analyzed,.Rubber and epoxy resin were used as sealing material,and the advantages and disadvantages of the selected materials are analyzed by finite element method.Combined with the advantages and disadvantages of the two materials,they will be used in combination.When filled epoxy resin and rubber volume ratio of 2:3,it can play a good sealing effect.The seal reliability and communication reliability test were carried out.(4)The detailed design of the intelligent sliding sleeve structure is carried out,and the intelligent slip sleeve is divided into the antenna part,the electric control part,the power part,the transmission part and the sliding sleeve part.The screw nut mechanism is adopted to rotate the motor into a straight line motion to realize the opening and closing of the sliding sleeve,and the design and analysis of the bearing clearance are carried out.Based on the dynamic seal research and the pressure conditions of the sliding sleeve,the compression ratio of the sealing ring used in the dynamic seal of the intelligent slip sleeve is chosen 15.6%.The maximum thrust force required for the sleeve at startup is 8087N,and the torque required for the motor is 51.5 N·m.Draw the parts processing,and use the 3D modeling of the assembly and interference analysis,complete assembly processing and prototype parts.Through the indoor pressure experimentt and pitching experiment to test the sliding sleeve sealing performance and slip sleeve opening adjustable.