Development of a bottom hole assembly for hydromechanical drilling

The solution to the problems of long hole drilling and construction is possible through creation of downhole tools on a fundamentally new ideological basis, involving physical principles and engineering designs unconventional in the field of drilling equipment. It is important to take into account that drilling energy inputs increase with depth. Following this concept, based on the tasks of geological exploration, a bottom hole assembly is developed and introduced into well drilling, with the design features and technological capabilities focused on a comprehensive solution to the problems of well drilling and construction. In addition to the outer pipe and core receiver, the bottom hole assembly is equipped with the diamond step drill bits with a separate system of flushing channels, collectively realizing the effect of hydromechanical drilling. By introducing an expander turbulator into the bottom hole assembly to convert an upward fluid flow into a rotary upward flow, the problem of removing drill cuttings from under the step drill bit is effectively solved. Production tests of the bottom hole assembly with core sampling were carried out at a complex deposit in Central Kazakhstan, in full-hole drilling for groundwater in the area of the Almaty Region. According to the results of the production tests, hydromechanical drilling of wells is especially effective in case of using the diamond step drill bits. The presence of an expander turbulator in the bottom hole assembly makes it possible to significantly increase the intensity of removal of drill cuttings from the bottom hole, especially in full-hole drilling. The focus of the research is the Development and implementation in drilling of wells of a small-sized, low-flow layout of hydraulic turbines with the selection of highly informative core (No. IRN AR19676688) that falls under grant financing for the implementation of scientific, as well as scientific and technological projects.The source of financing is the Committee of Science of the Ministry of Science and Higher Eduction of the Republic of Kazakhstan.