## 3 Experimental Setup  
In this study, the detailed introduction of the developed heat recovery system and the examination of the efficiency of the system depending on the cutting parameters and operating conditions will be made. Because the changes in the cutting speed, feed rate, and coolant solution ratio will change the cutting performance as well as affect the energy consumption and heat recovery. In this respect, determining the optimum conditions is important. In traditional cooling systems, the coolant heated in the cutting zone flows to the coolant tank located under the machine by its own gravity. In this classical approach, the heated coolant naturally gives its heat to the environment while in the tank, and thus, the coolant cools. In this way, a homogeneous cooling does not occur over time. This negatively affects the processing quality and means that a significant amount of heat energy is wasted. On the other hand, since the coolant will deteriorate more quickly at high temperatures, coolant consumption and environmental risks will also increase. As a solution to all these problems, a coolant cooling and heat recovery system has been developed in this study. In some advanced machines, there are applications where the coolant is cooled using a heat exchanger in the cooling tank. However, no theoretical or practical study was found  
Figure 4: Machine tool used in experiments.  
Figure 3: Datalogger used in the experiments.  
regarding heat recovery in processing within the scope of the literature research conducted during this study. In this respect, the study is original. As will be seen at the end of this article, the patent for this developed system has also been obtained. The experimental setup created using the developed system is shown in Figure 5.  
In this new integrated system, the heated water mixture taken from the cooling tank of the machine tool is sent to the heat recovery system integrated into the machine tool with the help of a pump. Here, the coolant, whose heat is taken and cooled to the desired constant temperature, is sent directly back to the drilling area of the drill. The heat taken is used to meet the hot water requirement and to heat the environment. Thus, in addition to heat recovery by cooling the cutting area, tool life is increased and cutting performance is also improved. Temperature sensors and flow meters are placed in the relevant parts of the system at the inlet and outlet. In this way, continuous data collection is provided. Thus, the physical condition of the coolant in the closed circuit between the machine tool and the recovery system can be effectively controlled. If the return temperature of the cutting fluid exceeds the set value, the control system steps in, makes the necessary adjustments, and reduces the temperature of the coolant to the specified value. In addition, the inlet and outlet temperatures and the coolant amounts in both the fan coil and the boiler are measured, and the amount of heat recovered is determined. During the operation, the system continuously records the measured data using a data logger at intervals as short as one minute. Subsequently, the recorded data are transferred to a computer in Excel format. The transferred data can be processed either through the data logger's interface or by utilizing alternative software tools. To achieve this, the system incorporates two turbine-type flow meters, twelve temperature sensors, and a data logger equipped with sixteen output channels.