Mining Project: Engineering Noise Controls for Longwall Mining Systems
To develop durable noise controls that reduce the noise exposure of longwall mining system crews and facilitate the commercialization of the controls to make them available for all miners.
|Keywords||hearing loss, mining, noise|
This project has four research aims, as follows:
- Identify and rank dominant noise sources on longwall mining systems, acquire operating data, collect laboratory data, and create computer modeling of noise controls.
- Develop and evaluate noise controls in the laboratory, refine and re-evaluate modified noise controls, and install and evaluate noise controls in a working environment.
- Perform a case study to assess performance and durability of noise controls.
- Transfer research findings to industry and develop related marketing media.
Approximately 50% of the coal mined in the US is extracted using longwall mining systems. Studies have shown that longwall crews in particular can be potentially overexposed, with sound levels as high as 105 dB(A). Such levels could lead to overexposure and potential hearing loss in as little as one hour.
This project focuses on reducing hearing loss of miners working in longwall units. Engineering noise controls will be developed to reduce the sound levels generated by longwall mining systems. A novel approach of this project is the use of modeling techniques to understand the vibration and noise radiation of longwall components. Prior to this project, researchers did not have the capability to develop and use numerical models for acoustic prediction in the development of noise controls for longwalls. Because a longwall may be over 1,000 feet long, it is impossible to test the complete systems in NIOSH laboratories. Instead, modeling will be used to understand longwall noise sources and to evaluate possible controls.
Laboratory measurements will be utilized to evaluate critical components and to validate models. An integral part of this research program will be working with industrial partners to assist in longwall modifications and to facilitate commercialization of the noise controls developed. Specifically, the industrial partners are the manufacturer of the cutting drums and a mine operator where the noise controls were installed for the production of an entire longwall panel. The effectiveness of these noise controls will be evaluated in a laboratory setting and in an underground setting to assess the reduction in worker exposure.
The goal of this research is to reduce the noise exposure for longwall operators and crew by at least 50%. The amount of reduction will vary with operating conditions, but in many instances the developed noise controls will eliminate the overexposure of the operator.