## 3 Stages of Drilling a Radial Borehole  
The hydraulic radial drilling technique for drilling small-diameter boreholes necessitates a departure from traditional methods of transmitting mechanical energy to the drill bit. This departure includes implementing mechanisms such as rotating drill pipes, torque from a downhole motor, or impact energy generated either mechanically or indirectly through a hydraulic medium. By harnessing the energy of the flowing jet from the nozzles, this method allows for the utilization of hydraulic energy, a direct application that was not previously employed, to hydro-turbine hard rock. The same principle applies when abrasive particles are introduced into the direct excavating fluid, enhancing the impact force on the hydroprobing rock surface. [PERSON], in his study, provided an example of developing drilling head solutions using the rock hydro-sanding method [18]. The measure of the energy required to drill a unit volume of rock during the drilling process is termed specific drilling energy. In the case of hydraulic radial drilling, it is more common to refer to the energy used to create a fracture in the rock [18]. This is calculated by dividing the energy by the product of the depth and width of the fracture and the velocity during the fracture-cutting process. In contrast, classical drilling discusses the total specific energy of drilling (TSE), expressed as the sum of the energy of rotational motion, the progressive motion of the drill pipe, and the hydraulic energy necessary to drill a unit volume of rock during the drilling process [2; 19; 20]. Based on analyses of production data from a specific deposit, as well as on geophysical, petrophysical, and other pertinent analyses, the parameters for reaming the deposit are determined. This includes selecting the appropriate levels within the deposit to be reamed and determining the length and number of radial boreholes to be drilled. These decisions are informed by a comprehensive understanding of the deposit's characteristics, ensuring that the radial drilling process is tailored to optimize production and reservoir performance. In order to search for a novel solution, the literature was reviewed in terms of requirementsand limitations regarding this technology. The main assumptions are compacted in the Figure 1.  
The process of drilling a single radial borehole involves the following sequential steps [21; 22]:  
* Pulling out the production equipment: the first step is to retrieve the production equipment from the well, along with any existing downhole equipment. * Cleaning the borehole: the borehole is then cleaned to prepare it for the subsequent drilling process. * Determining the correct depth and orienting the deflector outlet: The correct depth is determined, and the deflector outlet is oriented using appropriate tools, such as a gyroscope. This operation can be performed after fastening the anchor. * Casing: Casings are installed on the borehole. A radial borehole drilling set enables drilling a window in the casing for further drilling behind them and includes components such as a deflector, an anchor, and other elements (control section). * Fastening the anchor: the anchor is securely fastened in place. * Fastening the window cutting tool: a tool for making a window in the casing pipe is attached to the capillary. * Making a window in the casing: using the window cutting tool, a window is created in the casing. * Pulling out the tool: the window cutting tool is then removed from the well. * Arming the capillary: The capillary is equipped with a flexible high-pressure elastic hose with a nozzle and is inserted into the deflector. Drilling is initiated to the specified length using the drilling set. * Retracting the drilling set: the drilling set is retracted from the hole while simultaneously flushing the borehole to remove the drill cuttings. * Pulling out the drilling set: The drilling set is completely removed from the well.