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Construction wells on the Achimov deposits was accompanied by many problems: the danger of sticking and oil, gas and water inflow; a serious decrease in the mechanical ROP on dense layers; severe downhole conditions: vibrations on dense interlayers, temperature up to 110°C, drilling mud based on diesel fuel. All of the above issues increased the number of trips due to equipment failures, increased non-productive time and, as a result, increased the well construction period. The integrated approach described in this work has significantly reduced non-productive and well construction time. The customer was suggested: –Limitation the mechanical rate of penetration (ROP) by 15m/h to control equivalent circulating density;–Control of the equivalent circulation density by the MWD sensor;–Combination of a modular motor with rotary steerable (RSS) system in bottom hole assembly (BHA) to increase the mechanical ROP during drilling in dense layers of the productive horizon;–Optimization of the bit design, taking into account geological features, meanwhile drilling with a rotary-steerable system;–Use of a new generation rotary- steerable system;–Optimization of the BHA;–Modernization of equipment preparation procedures. An integrated approach to drilling wells on the Achimov deposits with new methods and technologies offered to the customer allowed reducing the number of failures by 100-200%, which reduced the number of runs, and as a result, the non-productive time decreased. The reduction in the number of runs allowed taking from 500 − 600 meters to 1200 − 1500 meters per run. Optimization of the bottom hole assembly, including a new bit design in Russian Federation, integration of a new generation of rotary-steerable system with a modular motor, made possible to expand the boundaries of drilling modes, accordingly increase the mechanical rate of penetration. In addition, the adopted methods and technologies allowed reducing the negative impact of vibrations that occur during the drilling of dense layers. Application of the integrated approach to solve the problems, which took place during the construction of wells on the Achimov deposits, has significantly reduced: the number of equipment failures, non-productive time. Meanwhile increased the mechanical rate of penetration and drilled distance in one trip, which in general has significantly reduced the time of well construction.

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Drilling multilateral (fishbone) wells in western Siberia is a common practice. A particular characteristic of these wells is the kickoff in the openhole horizontal section—no cement plug or whipstock is used. In the overwhelming majority of wells, it is economically impractical to perform tripping procedures twice—to change the bottomhole assembly (BHA) for the kickoff, and change it again for subsequent drilling. To reduce the well construction time, one requirement is to drill the horizontal section in one run. Many operators have realized the advantages of using rotary steerable systems (RSS) for drilling multilateral wells that are becoming more complicated. During a well startup, the use of RSS to drill fishbone wells caused some concern about kickoff procedures. The operator had no experience with the process due to the analogue of adjustable kick-off sub (AKO) on the positive displacement motor PDM absence. The first kickoffs were made and resulted in a significant time increase compared to the same process with (PDM): 26 to 28 hours instead of 16 to 20 hours. Further experience with using kickoffs with RSS resulted in procedures and process improvements. Based on the experience gained, a new kickoff procedure with RSS was tested at more than 20 jobsites in Western Siberia. A notable record was achieved on one of the multilateral wells on March 18, 2018 at the job for Lukoil-Zapadnaya Sibir Ltd. The kickoff in the open horizontal section was made in 1 hour 40 minutes, whereas the standard procedure took 20 hours 30 minutes. The time reduction of the kickoff process was 92% compared to the standard procedure, and 17% compared to the previous set record. The next stage of this technology will be its application in Eastern Siberia, with some modifications based on the lithostratigraphic section of the target horizon.

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