Michael Robert, Yantek David, Johnson David, Ferro Ernie, Swope Chad
Penn State Erie, The Behrend College, School of Engineering, 5101 Jordan Road, Erie, PA, 16563 USA;
NIOSH, 626 Cochrans Mill Rd, Pittsburgh, PA 15236 USA;
Noise Control Eng J. 2011 Nov 1;59(6):591-612. doi: 10.3397/1.3659660.
Among underground coal miners, hearing loss remains one of the most common occupational illnesses. In response to this problem, the National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) conducts research to reduce the noise emission of underground coal-mining equipment, an example of which is a roof bolting machine. Field studies show that, on average, drilling noise is the most significant contributor to a roof bolting machine operator's noise exposure. NIOSH OMSHR has determined that the drill steel and chuck are the dominant sources of drilling noise. NIOSH OMSHR, Corry Rubber Corporation, and Kennametal, Inc. have developed a bit isolator that breaks the steel-to-steel link between the drill bit and drill steel and a chuck isolator that breaks the mechanical connection between the drill steel and the chuck, thus reducing the noise radiated by the drill steel and chuck, and the noise exposure of the roof bolter operator. This paper documents the evolution of the bit isolator and chuck isolator including various alternative designs which may enhance performance. Laboratory testing confirms that production bit and chuck isolators reduce the A-weighted sound level generated during drilling by 3.7 to 6.6 dB. Finally, this paper summarizes results of a finite element analysis used to explore the key parameters of the drill bit isolator and chuck isolator to understand the impact these parameters have on noise.
在地下煤矿工人中，听力损失仍然是最常见的职业病之一。针对这一问题，美国国家职业安全与健康研究所（NIOSH）矿山安全与健康研究办公室（OMSHR）开展研究，以降低地下采煤设备的噪声排放，其中一个例子就是锚杆钻机。现场研究表明，平均而言，钻孔噪声是锚杆钻机操作员噪声暴露的最主要来源。NIOSH OMSHR已确定钻杆和卡盘是钻孔噪声的主要来源。NIOSH OMSHR、科里橡胶公司和肯纳金属公司开发了一种钻头隔离器，该隔离器打破了钻头与钻杆之间的钢对钢连接，以及一种卡盘隔离器，该隔离器打破了钻杆与卡盘之间的机械连接，从而降低了钻杆和卡盘辐射的噪声以及锚杆钻机操作员的噪声暴露。本文记录了钻头隔离器和卡盘隔离器的发展历程，包括各种可能提高性能的替代设计。实验室测试证实，生产型钻头和卡盘隔离器可将钻孔过程中产生的A加权声级降低3.7至6.6分贝。最后，本文总结了有限元分析的结果，该分析用于探索钻头隔离器和卡盘隔离器的关键参数，以了解这些参数对噪声的影响。
