At present, rotary steerable systems are widely used for drilling wells with a large departure from the vertical. The article presents the reasons for the decrease in the system's operability when drilling wells in the territory confined to the Verkhnekamskoye deposit of potash-magnesium salts. The design of the control system of the drilling device is determined, which is pin-joint shaft, which is rolled in supporting node. The shaft angle change is made by creating a deflection force with three wedges located at a radial offset of 120 degrees relative to each other. Each wedge is set in a motion by an electric motor with a planetary gear. The maximum angle of the shaft is 2.5 degrees.
The pin-joint shaft is subjected to strength calculations, which are acted on by axial load, torque and pressure of the drilling fluid during drilling, since the greatest loads arise in the joint of the pin-joint shaft. Mathematical strength calculations evaluated the efficiency of the pin-joint shaft at various parameters of the well drilling mode with horizontal termination. Under the most severe loading conditions, the safety coefficient of the pin-joint shaft at the design maximum contact pressure is equal to 2.75, the calculated value of the contact stresses is lower than permissible. In addition, in the software multi-processor complex ANSYS, the shaft is modeled by the finite element method. The maximum stresses obtained in the contact zone of the keys with the cylindrical grooves of the driven shaft are lower than the design tolerances. This confirms the correctness of the materials choice and design of the control system.
During the construction of directional wells with a large deviation from the vertical in fields confined to the Verkhnekamskoye deposit of potash-magnesium salts, the control system should provide transmission to the bit with an axial load of up to 180 kN, a torque of up to 10 kN∙m and a flush fluid pressure of up to 40 MPa.
1. Baldenko D.F., Vervekin A.V., Plotnikov V.M., Ways to further improvement of well drilling by downhole drilling motors (In Russ.), Vestnik Permskogo natsional’nogo issledovatel’skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2016, no. 19, pp. 165–174, DOI: 10.15593/2224-9923/2016.19.7
2. Samigullin V.Kh., Preduprezhdenie i likvidatsiya oslozhneniy pri burenii gorizontal’nykh skvazhin (Prevention and control of complications when drilling horizontal wells): thesis of candidate of technical science, Ufa, 1999.
3. Nikolaev N.I., Kozhevnikov E.V., Enhancing the cementing quality of the well with horizontal profile (In Russ.), Vestnik Permskogo natsional’nogo issledovatel’skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2014, no. 11, pp. 29–36, DOI: 10.15593/2224-9923/2014.11.3
4. Barton S., Card K., Pierce G., Delivering steering success in problematic soft-formation directional wells, SPE 115138-PA, 2009.
5. Sugiura J., Bowler A., Lowdon R., Improved continuous azimuth and inclination measurement by use of a rotary-Steerable system enhances downhole-Steering automation and kickoff capabilities near vertical, SPE 166099-PA, 2014.
6. Gravem T., Lee J., Lofts J., Fast track to optimum well positioning: Inteq logging-while-drilling technologies are improving real-time formation evaluation and well positioning, Hart’s E and P, 2006, Issue JULY.
7. Krysin N.I., Melekhin A.A., Dombrovskiy I.V. et al., Study of an information transmission channel in drill pipes during wells construction using rotary steerable system (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 11, pp. 80–82.
8. Khalilov A., Prevention and control of complications when drilling horizontal wells (In Russ.), Burenie i servis, 2016, pp. 58–60.
9. Rynok bureniya gorizontal’nykh skvazhin i zarezki gorizontal’nykh bokovykh stvolov: tekushchee sostoyanie i prognoz razvitiya do 2027 goda (The market of horizontal drilling and horizontal sidetracking: current state and development forecast until 2027), URL: http://rpi-consult.ru/reports/dobycha-nefti-i-gaza/rynok-bureniya-gorizontalnykh-skvazhin-i-zarezki-...
11. Ust’kachkintsev E.N., Increase productivity of construction in sidetrack of Verkhnekamsk potassium-magnesium salts field (In Russ.), Vestnik Permskogo natsional’nogo issledovatel’skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2012, no. 5, pp. 39–46.
12. Novosel’tsev D.I., Epikhin A.V., Anisimov A.V., A method, applied for calculation of loads on the deflection module of the rotary steerable system to determine the risk of the system failure (In Russ.), Stroitel’stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2017, no. 6, pp. 4–8.
13. Patent application no. 2017113661 RF, Blok otkloneniya sistemy upravleniya burovym ustroystvom (Deviation block for the drilling control system), Inventors: Melekhin A.A., Turbakov M.S., Rusinov D.Yu., Chernyshov S.E., Zlobin A.A.14. Pisarenko G.S. et al., Spravochnik po soprotivleniyu materialov (Handbook on the resistance of materials), Kiev: Naukova dumka Publ., 1988, 736 p.