Application of wireline method is the most enforced way of drilling deep boreholes. For optimal drilling performance of the borehole, it is necessary to obtain knowledge about wireline system, operation of the system, components of the system and selection of correct drill bit with correctly defined drilling parameters. The main feature of the wireline method is a faster acquisition of drilled core to the surface with wireline cable and inner core barrel. With wireline system the maneuver time of the obtained core is greatly reduced comparing to the conventional drilling method. The most important features of the system are a specially designed core barrel that allows that the inner tube is pulled to the surface with a wireline hoist system mounted on the drilling machine, and wireline drill rods which are larger diameter than the inner core barrel. Larger diameter of rods allows the inner core barrel to travel from bottom to the surface and back to the bottom of the borehole. For advancement in various ground massifs, it is very important to choose the right drill bit which is mounted on the outer tube of the core barrel. It is also necessary to adjust the drilling parameters according to the drill bit used and geology of ground massif. The aim of core drilling is to obtain geological and geotechnologyical properties of the ground massif. Therefore, several exploratory measurements, such as presiometric measurements, hydrogeological measurements and mass structure measurements can be performed during the borehole construction. Massif structure measurements are carried out with a core orientation system installed on the core barrel of the wireline system.
The project presented in the practical case of the master's thesis deals with the implementation of the deep boreholle VSG-803-V3p, which was carried out in the framework of the research phase for project 3. razvojna os sever.
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