Study On Rock Breaking Process And Energy Dissipation Characteristics Of Open-Pit Drilling

In the drilling of open-pit mines,how to obtain the energy consumption of rock breaking by cone drilling through drilling related parameters is an important issue in studying drilling efficiency.The paper is based on the project of Liaoning Provincial Department of Education ’s ’ Research on the Dynamic Perception of Energy Consumption in Mine Drilling and the Optimization of Ore Crushing Energy Utilization ’(LJKZ0282).Response Relationship between Axial Pressure and Rotational Speed of Rotary Drill and Rock Breaking Speed and Energy Consumption.The characteristics of thrust and shear rock breaking are studied by theoretical analysis,laboratory test and numerical simulation.And relation model between axial pressure and rotational speed and rock breaking dissipation is established,to provide a reference foe improving drilling efficiency.The main research contents and results are as follows:(1)According to the structure and force analysis of cone bit,the rock breaking characteristics and energy dissipation characteristics of indoor rotary drilling test and numerical simulation are studied.The rotary drilling rock is divided into initial drilling stage and stable drilling stage.The drilling speed of rotary drilling test increases with the increase of axial pressure and rotational speed,and the energy consumption of rock breaking increases with the increase of drilling depth.The energy time density decreases first and then increases with the increase of rotational speed,and there is a minimum value between rotational speed and axial compression.(2)The rock breaking model of YZ-35 D rotary drill is established by finite element simulation method,and the model material parameters of hematite,green mudstone and phyllite are determined.The influence of rotary speed and axial pressure on drilling speed is analyzed.It is found that the displacement and time of the cone drill are linearly increased when drilling the rock.In order to improve the drilling speed,the axial pressure and rotation speed should be increased at the same time when drilling the solid rock.The low axial pressure and high rotation speed should be selected when drilling the relatively solid rock,and the high rotation speed and medium axial pressure should be selected when drilling the medium solid rock.(3)The relationship between rock breaking energy consumption and displacement when drilling hematite,green mudstone and phyllite under axial pressure and rotational speed was studied.According to the drilling speed and energy density,the drilling efficiency evaluation function is established.The results show that: There is an exponential correlation between the energy consumption per meter and the drilling displacement in the stable drilling stage of rotary drill.The optimum range of drilling speed and energy density for drilling hematite,green mudstone and phyllite is obtained.Verify the accuracy of energy consumption calculation and drilling speed by comparing the test data of drilling hematite and phyllite in the field.It provides reference value to guide the calculation of energy consumption and efficiency evaluation of rock breaking by tooth wheel drilling.