The First Successful Application of Intelligent Management Pressure Drilling Solved Serious Drilling Complex Problems in the Qiulitage Block of the Tarim Basin, China

Abstract Drilling operations can easily lead to complex mud kick and loss in the Qiulitage block of the Tarim Basin. There are two sets of salt-gypsum layers and one set of high-pressure salt water layer in this block. The safe mud density window for drilling is only 0.01g/cm3. Conventional drilling cannot control the safe drilling of this block. The first successful application of intelligent management pressure drilling (MPD) solved serious drilling complex mud kick and loss of this block. MPD was used for the first time in ZQ-X Well of this block to successfully drill through the salt gypsum layer and high-pressure saline layer. During the drilling process, the actual pore pressure and loss pressure are measured to accurately determine the upper and lower limits of the pressure window. The bottom hole equivalent circulation density (ECD) is precisely controlled through the surface back pressure method, which effectively solves the mud kick and loss of the salt-gypsum layer and high-pressure brine. After the application of MPD, no serious mud kick, loss and stuck pipe accidents occurred in ZQ-X Well. The non-operating time (NPT) of the entire drilling was significantly reduced. Compared with conventional drilling, the water output of the saltwater layer was effectively controlled, and the average daily water output was reduced from 19m3 to 2.3m3. The saltwater-contaminated mud is extremely lightly polluted. The workload of mud maintenance was reduced, the amount of glue added is reduced from 2.4m3/h to 1.8m3/h. The consumption of barite powder was reduced from 117t/d to 45t/d. The diesel consumption was reduced from 23m3/d to 12m3/d. The drilling string lifting speed during the MPD was reduced from 40-50 seconds per string to 70 seconds per string, the MPD section was 3000m, and the drilling time was only increased by 1.5-2 hours, which can greatly reduce the risk of well control. The processing time is greatly shortened and the processing is simple. The processing is completed 10 hours after the mud kick overflow occurs in conventional drilling, and the MPD processing process only takes 0.5 hours. Precision MPD was successfully applied in the Qiulitage block of the Tarim Basin, providing an excellent technical case for dealing with complex mud kick and loss accidents of salt-gypsum layers and high-pressure saline layers. Drilling safety in this type of block is improved. Drilling time and comprehensive drilling costs are reduced. For salt-gypsum layers and high-pressure saline layers, it is recommended to promote the application of advanced managed pressure drilling.