Design And Implementation Of Downhole Television System With Spiral Water Jet

Oil and gas wells have the characteristics of large workload and high difficulty.They are prone to failure during operation.Traditional downhole TV technology cannot accurately and efficiently complete logging tasks in relatively turbid well fluids.The research team has designed a set of downhole TV system based on spiral water jet technology.The spiral water spray device at the front end of the system can clean the turbid well fluid to ensure clear imaging of the front camera of the system,and can effectively complete the oil and gas well in the turbid environment.Logging task.1.Detailed analysis of the working environment and functional requirements of the downhole TV system,to set goals for the design of the entire system,focusing on the various components of the underground TV system and the important functions of the core module.According to the functional requirements of the system,the overall mechanical structure of the system is determined.The wall thickness of the thin-walled pipe and the sealing problem of the system are theoretically studied and systematically analyzed.The system circuit is integrated with the mechanical structure.2.The finite element analysis software ANSYS was used to analyze the transient factors of the three factors(spray angle,nozzle number,nozzle velocity)that affect the water spray effect.A finite element simulation model is established based on the actual flow field conditions.In order to ensure that different working conditions can be compared with each other,a unified quantitative index of water spray effect is established.The simulation analysis shows that when the nozzle spiral angle is between,the number of nozzles is 8,and the proportion of oil in the external simulation well fluid initialization process is 40%,the water spray device can simulate the volume fraction of water in the well fluid within 60 seconds.Increased to about 95%,basically meet the imaging requirements of the camera.The influence of the number of nozzles on the water spray effect was analyzed.It can be seen from the simulation comparison results that in the four working conditions with the number of nozzles 5~8,the more the number of nozzles,the better the water spray effect.Finite element simulation analysis is carried out on different nozzle flow rates.When the nozzle flow rate increases,the time required for the external volume of water in the simulated well fluid to reach 90% is gradually shortened,but the excessive flow rate will reduce the solubility of the gas in the well fluid.,a large number of blisters are generated,which affects the imaging of the camera.The simulation analysis results have certain guiding significance for the selection of the nozzle flow velocity in actual production.3.According to the results of the simulation analysis,the downhole TV function prototype was processed.Firstly,the mechanical structure and system circuit integration of the functional prototype are described.Secondly,the construction of the experimental platform and the specific experimental scheme are analyzed,and several typical working conditions are analyzed.When the nozzle spiral angle is 10°,the number of nozzles is 8 or the nozzle spiral angle is 25°,and the number of nozzles is 5,the water spray effect is poor.When the nozzle spiral angle is 25° and the number of nozzles is 8,spray The water effect is good,the functional prototype can rinse the well fluid at 60 seconds,and the downhole TV system can capture the clear image of the pipe wall in real time.