POWER CONSUMPTION OF ROCK DECOMPOSITION PROCESS DURING DIAMOND CORE DRILLING USING PULSE FLUSHING

Purpose. To study the impact of pulse flushing on the power consumption of rock decomposition during diamond core drilling. Methods. Theoretical analysis, processing of the obtained experimental data. Findings. The decrease in power consumption of rock decomposition process during drilling with jet pulse flushing was studied. The influence of the bottom-hole power and jet pulse flushing parameters on the efficiency of rock decomposition process was investigated. Physical mechanisms of mining rock degradation under the jet pulse flushing were considered in the article. Originality. It was established that the drilling performance is growing along with increasing of pauses between the flushing liquid supply intervals. At that, the relative reduction of energy consumption of the rock decomposition process is increasing when the bottom-hole power is decreasing. The study provides theoretical grounds for the increase in the mechanical rate of drilling during the jet pulse flushing owing to utilization of the generated frictional thermal energy in the bottom-hole. It is demonstrated that using pulse flushing intensifies the processes of thermal cycling degradation of the mining rock. Practical implications. It is demonstrated that the pulse flushing mode has a potential to improve the performance of diamond core drilling. The outcomes of the research can be useful for grounding the specifications of the jet pulse flushing method during the development of the energy saving modes of diamond core drilling processes.