Noise reduction potential of a variable speed driven coal mining conveyor.
Burks JA; Bartholomae RC
New Technology in Mining Health & Safety: Proceedings of the Symposium held at the SME Annual Meeting, Phoenix, Arizona, February 24-27, 1992. Khair AW, ed., Littleton, CO: Society for Mining, Metallurgy, and Exploration, 1992 Feb; :43-51
The chain conveyor is utilized extensively in underground mining to convey raw ore, especially coal. It is one of the most significant contributors to the occupational noise problem experienced by miners in the underground coal mining environment. Conventional engineering noise controls that result in an average reduction of 4 dba have been previously designed and implemented. However, a novel solution involving a change in conveyor operation has been proposed that takes advantage of two aspects of conveyor noise: (1) conveyor noise has an approximately cubic dependence on conveyor chain speed and (2) due to the damping provided by coal, a full conveyor is 5 dba quieter than an empty one. An engineering analysis by the U.S. Bureau of Mines has shown that a significant reduction in the operating noise level of a typical continuous miner can be achieved through the use of an adjustable-speed drive automatically controlled by a coal-loading sensor that maintains a full conveyor at all times. The potential reduction depends primarily on the mining conditions (coal seam thickness and the presence of either rock or water) and ranges from 7 to 18 dba. Other benefits to be derived from the use of a variable-speed drive include reductions in power consumption, dust, and maintenance costs.
Mining-industry; Underground-mining; Coal-mining; Mining-equipment; Noise; Noise-control; Engineering-controls; Control-technology
OP; Conference/Symposia Proceedings
New Technology in Mining Health & Safety: Proceedings of the Symposium held at the SME Annual Meeting, Phoenix, Arizona, February 24-27, 1992