Under CopyrightGeißler, NiklasNiklasGeißlerGarsche, FlorianFlorianGarscheSamus, VitaliiVitaliiSamusBracke, RolfRolfBracke2023-03-202023-03-202022https://publica.fraunhofer.de/handle/publica/437832https://doi.org/10.24406/publica-107410.24406/publica-1074The main component of the MTD process is a high-speed micro drilling turbine driven by high-pressure fluid. Equipped with an impregnated diamond drill bit, it is possible to cut through hard rock and steel in a single operation. This eliminates the need to change the drill bit during operation, saving time and money. To connect a formation using ⌀40 mm micro-sidetracks, a deflector shoe is installed inside the cased well to the desired drilling depth using jointed pipes. Then, the drilling unit attached to a flexible hose is run in to drill first through the casing and then further into the formation. The compact design of the drilling tool allows a deflection of the micro sidetracks of approx. 50°in a 5 1/2" casing. Since the drilling tool consists of temperature-resistant components, the MTD can also be used for very deep, high-temperature geothermal wells. Conclusion Tests have proven that the MTD can be used to drill micro-sidetracks from a well through steel casing into hard rock such as granite. This way, surrounding fracture zones can be connected and production rates can be increased in a cost-effective manner. This was not possible for us with previous technologies such as conventional Radial Jet Drilling-RJD 3 and now opens up new possibilities for the geothermal industry.enposter