The Research And Development Of Micro Flux Detection Experimental Device

With the development of petroleum exploration to more complicated deep formation, encountered in drilling narrow safety density window has become more and more prominent, which is seriously restricting the development of oil exploration industry. Micro flux control(MFC) pressure drilling technology is an improved controlled managed pressure drilling technology, which combine the advantages of under balanced drilling and conventional drilling technology. It has abilities of accurate detection influxes and losses, accurately judging the invasion of the amount of fluid in the wellbore and calculating the accurate formation pressure, and timely feedback control so that the bottom hole pressure in the window, effectively ensure the safety of drilling. At present, this technology has been mature in foreign countries, we only bring in the technical services, still in the stage of research and development.In view of this, this article, based on the existing micro flow detection technology and equipment, proposed a set of micro flux detection experimental device for micro flow detection technology analysis and research, to provide theoretical reference for field micro flux detection technology, also in order to improve the effect of micro flow detection technology in the field test and application. The following results are achieved:(1) Based on the MFC, I analyzed the thinking of micro flux detection technology, which estimate the influx volume in bottom hole by detecting and computing borehole annular flow rate, and acquired relatively exact formation pressure.(2) According to the thinking of micro flux detection technology, I have cleared the main technical parameters of the experimental device, selected the optimum Reynolds similarity as the main similarity criterion, calculated the main parameters, determined the experimental device should meet the functions and system framework.(3) According to the calculated main technical parameters and characteristics of MFC, I have designed the micro flow test device minutely, the experimental device can simulate normal drilling fluid circulation experiment in the closed loop system, can have gas influx and liquid loss respectively.(4) Experiment with the device, the results show that it can detect the influxes or losses in the designed influxes or losses range, detecting influx early and the desired effect was brought into effect.This paper combines micro flux detection technology in MFC and similarity theory, designed micro flux measurement experiment device, and carried on a lot of tests, the results show that the theory and methods used in this paper are feasible; The development of test device lay a foundation for the technology of detecting bottom hole pressure by micro flux study, the test results provide theoretical support for the development of bottom hole pressure changes due to micro flux and its related technology.