Generalized method of calculating energy expenditure at work undirected bottom of the drill string configurations for rotary drilling method

Abstract

The article deals with the important issue of increasing technical and economic performance and energy
efficiency of drilling oil and gas wells by improving technical means and scientific and methodological foundations
of their design and choice. The impact of undirected layouts of the bottom part of the drill string on the management
of drilling trajectory and energy costs which are arising have been characterized. The international experience
solving design issues, selection and exploitation of the undirected layouts of the bottom part of the drill string with a
different number of support-centering elements has been analyzed. In addition, the main approaches and techniques
used in the design of the undirected layouts are defined and criteria which are decisive in their choice for different
tasks of the directional drilling. The process of milling borehole wall by working elements of the support-centering
elements of rotation and axial movement of non-oriented layouts in the mining production.
In order to enhance the level of the research the mathematical models of the undirected layouts of the bottom
of the of the drill string without centralizers, as well as with one and two centralizers by taking into account the
dismemberment of their structures on individual items with different weight per meter and the bending rigidity and
bending moment at the upper contact of tubes with the borehole wall.