Draglines are dominant machines and the most significant electricity consumers in surface coal mines. With the growing price of energy, environmental concerns, and the high sensitivity of mine profitability to dragline productivity, any improvement in efficiency of dragline will be beneficial for mines. Research has shown that operator practices have a significant impact on energy efficiency of mining loading tools. However, not enough work has been done to provide guidance on how to quantitatively assess the effect of operator practices on dragline energy efficiency.
The objectives of this work were to: (i) test the hypothesis that dragline operator\u27s practices and skills significantly affect dragline energy efficiency; and (ii) develop a methodology to identify the critical parameters that explain the differences in operator energy efficiency. Statistical tests are suggested to study the effect of operator practice and skills on dragline energy efficiency to achieve the first research objective. The second objective was achieved with a novel methodology based on sound statistical principles. Both approaches were illustrated with a real-life dragline operation. The suggested methodology was used on the data collected from an 85yd³ BE-1570w dragline to compare the energy efficiency of five operators during a one month period.
Valid methods have been formulated for testing operator effects on dragline energy efficiency and for identifying critical parameters that explain such differences. Using the developed approaches, the case study shows that operator practices can affect dragline energy efficiency. The tests show that there is a high probability that differences in energy efficiency are due to dumping height, vertical and horizontal drag distances, and spotting and dumping time among the surveyed operators --Abstract, page iii
