A bolter miner is a new type of mining machinery with cutting and anchoring functions. Owing to its structural diversity, the cutting head performance of a bolter miner varies. However, there is still no effective method to evaluate the cutting head performance. Based on multi-aspect factors influencing the cutting head performance, the main factors such as the load fluctuation coefficient, mean torque, and specific energy were taken into account. Combined with the characteristics of multi-criteria decision-making approaches and the superiority of game theory in calculating the weight of the cutting performance indexes, an evaluation method based on the game-theory-extenics model is proposed. In addition, by combining the geological conditions of a particular coalmine, three pick layout schemes for the cutting head are compared, the final one of which was chosen through a performance evaluation. The results were successfully applied to the first shield bolter miner in China, and good results were obtained for engineering application.
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IntroductionThe traditional technology for coal lane tunneling is to cut in front using a cutting equipment and anchor at the back using a roof-bolter. The advancing speed of a cutting equipment is relatively quick, but the anchor work of a roof-bolter takes up too much time, leading to a serious imbalance in the excavation time. A bolter miner is a new type of mining machinery with cutting and anchoring functions, and can make the excavation and support stages progress synchronously, thereby improving the imbalance of the coal lane tunneling. The break up of coal-rock is completed using a front swingable cutting head. And the quality of its design directly affects the reliability, economy, and rapidity of the work being conducted. A cutting head is complex in structure and has a wide range of pick layouts, which have different geological adaptabilities. At the same time, how to select a cutting head with the best performance for the different working conditions has been widely studied by scholars both domestically and abroad Kang et al., 2016;Zhang et al., 2016).Differing from traditional cutting equipment, like a shearer or a roadheader, a bolter miner cutting head has no helical vane. And its difference in structure leads to a significant difference in mechanical properties between the cutting head and the helical drum (Ma, 2017;Gao et al., 2012). Owing to the short development time of a bolter miner (Vierhaus and Rainer, 2002;Leeming et al., 2001), there have been few reports on its pick layout of a cutting head thus far, however, many scholars have conducted in-depth studies on other helical drums used in cutting equipment. For example, the cutting torque, cutting force, and load fluctuation coefficient have been applied as indexes, and the best pick layout scheme of a shearer was selected under different working conditions (Zhao and He, 2011;Li et al., 2014;Du et al., 2009). Based on an analysis of the vertical vibration characteristics of a continuous miner (...