What will the program achieve?
Research Goal 3.1 - Reduce noise on continuous mining machines using coated flight bars
The following related research and development efforts are currently being conducted by the HLR program. Outputs, transfers, and outcomes are expected in the near future.
Reducing noise on continuous mining machines using jacketed tail roller
This project complements the coated flight bars innovation for continuous mining machines in underground coal mines (see Intermediate Outcome 3.1 above). The tail roller is located at the back end of the continuous mining machine’s conveyor. Noise levels may be reduced by jacketing the roller with a constrained layer damping treatment. Laboratory and field testing has shown this product can reduce the noise level at the operator’s position by as much as 3 dB(A). Furthermore, the jacketed tail roller may be applicable to other underground mining equipment such as loaders and shuttle cars, which could reduce the noise exposure of the operators of these types of equipment as well. In order to raise industry awareness of the engineering noise controls developed through this effort, the research results will be published in a trade magazine article and presented at industry briefings concerning noise exposure in the mining industry. The effects of the engineering controls are expected to begin in 2006, when underground test results are finalized and published.
Jacketed tail roller on a continuous mining machine
Reducing noise from the dust collector fan on continuous mining machines
HLR program researchers are involved in the development of noise treatments for a dust collector fan, which is a vane axial fan located inside the continuous mining machine. The effort resulted in an overall A-weighted sound power level reduction of 5 dB with only a 4% reduction in the volume flow velocity through the dust collector. This research complements the work on coated flight bars and the jacketed tail roller on continuous mining machine conveying systems. The engineering noise controls developed as a result of this research, along with the prior research on the continuous miner’s conveying systems (coated flight bars and jacketed tail roller), could lead to an overall noise reduction of up to 10 to 12 dB(A) at the operator position of the continuous mining machine. With these controls properly installed, it is anticipated that noise exposure for 90% of the operators of continuous mining machines will fall below MSHA’s permissible exposure limit. To raise industry awareness of the engineering noise controls developed through this work, research results will be published in trade magazine articles and presented at industry briefings concerning noise exposure in the mining industry. The effects of the engineering controls are expected to begin in 2006, when underground test results are finalized and published.
Dust collector fan for continuous mining machines