Research On Electromagnetic Detection Technology For Damage Of Sand Control Screen In Oil And Water Well

The production progress of most oil fields of our country have entered the middle and late stages.Due to various factors such as chemical corrosion,sand production,faults,slippage,perforation and artificial high pressure mining,the sand control screen tube has been damaged in different degree,which seriously affected the normal development of production wells in this wells and even the whole block,and posing a great threat to the continuous production of oil fields.Aiming at this problem,this paper studies the damage detection of sand control screen pipe in oil and water wells,and mainly includes the establishment of the sand control screen tube model,the determine of screen damage detection,the optimization design of the underground circuit system and the analysis of the field experiments.Firstly,this paper introduces the basic theory of the sand control screen tube damage detection,and analyzes the main differences between sand control screen and casing in damage detection.Secondly,the damage detection model of eccentric array for the sand control screen is deduced according to the electromagnetic logging theory and the specific structural characteristics of the sand control screen.Based on this model,the overall structure of the sand control screen damage detection system and the spatial distribution of the eccentric probe are introduced,a method for judging the damage detection of sand control screens is proposed,the feasibility and accuracy of the system are verified by analyzing the results of designed relevant experimental.In addition,the transmitting circuit,pre-differential amplification circuit,low-pass filter circuit and multi-channel data acquisition circuit of downhole detection system are optimized.To realize the intellectualization of the damage detection system,reduce the cost and improve the reliability,a real-time storage circuit for downhole data is designed according to the particularity of downhole operation.Finally,based on the overall system circuit optimization,conducted a large number of indoor and outdoor experiments.The experimental results show that the electromagnetic detection method for sand control screen in oil-water well can accurately locate the damage type,location and size of sand control screen and provide important basis for taking effective remedial measures in time,improving the quality of Oil and gas exploration,and provide important basis for the continued development of the oil fields.