Chernova M. Development of scientific bases for increasing the efficiency of drilling deep sloping wells (for the conditions of oil and gas fields of Ukraine)

The dissertation is devoted to the development and implementation of a complex of highly efficient technical means, devices and technologies, to increase the efficiency of the drill pipe column, the layout of the bottom of the drill string to increase the drilling speed of deep sloping oil and gas wells in the fields of Ukraine. The scientific bases of estimation of durability of elements of a drill string are improved, taking into account the theory of nonlinearity and basics of criteria of fracture mechanics. The influence of oscillations on the properties of the hydrodynamic circulation processes of the flushing fluid and the dynamics of the drill string during deep well drilling are determined. Mathematical substantiation was performed and mathematical models were applied for the development of structures of chambers of hydro oscillation generators and for determination of their location in the layout of the bottom of the drill string, with subsequent industrial introduction. A rock-destroying tool has been developed, which is directly coupled to the oscillation generator to increase the drilling speed by increasing the efficiency of bringing the axial load into the borehole. The influence of the coating of polymeric-composite materials of the elements of the drill string on the impedance of the motor in the well and on the prevention of their entrapment in deep inclined-directional wells is determined. The technology of coating polymer-composite materials on the basis of fluoroplast F4 elements of the drill string for working conditions in deep wells with high thermobaric parameters is developed. Based on a mathematical modeling method based on mathematical calculations based on the ratio of elasticity and equation of motion of a curvilinear element, a new methodology for constructing sickle-shaped concentrators for directional energy generators to strengthen the thread surface of locking threads is developed. The design of the sealing element, based on polymer F4, locking threaded connection of casing and pumping tubes for conditions of operation in deep wells with high thermobaric characteristics has been improved.