Sandvik’s Newcastle-based Voest Alpine Mining and Tunnelling Pty Ltd has adopted soundproofing specially developed by Pyrotek’s Soundguard division in the construction of Sandvik underground loaders bound for overseas markets and notably China.
The use of the modified version of Soundsorber Barrier acoustic composite to insulate the engine bay hatches of the massive machines is particularly significant in the case of the Chinese market as ushering in a new era of attention to OHS issues in a country lagging modern standards of mine safety.
The use of soundproofing at all testifies to a heightened concern for the hearing and comfort of China’s mine workers. Due to confined space and the diesel engines being in close proximity to the operators, noise levels can easily exceed safe limits without soundproofing.
With it, the noise is cut to comply with the Occupational Health and Safety Regulation 2001—Reg 49 limit set in Australia, which makes employers responsible for ensuring workers are not exposed to more than 140 dBC or an 8-hour noise level equivalent of 85 dBA.
Of course the major concern is to meet the demand for “strictly explosion-proof equipment only” in the hazardous mining environment. To this end the designers have worked with Pyrotek to develop a special version of Soundsorber Barrier, replacing the usual aluminium facing of this excellent acoustic composite with Mylar, which does not accumulate static charge.
Soundsorber Barrier is a composite of a flexible acoustic barrier between two layers of hydrolysis resistant acoustic foam, the thinner of which, the isolation layer, decouples the flexible barrier and the thicker, the absorption layer, reduces airborne noise.
National Acoustic Laboratories test results give a range of sound transmission loss for Soundsorber Barrier from 20 dB at 125 Hz to 35 dB at 4000 Hz. Its fire-related indexes are all zero except for the smoke developed index, which is rated zero to one.
Pyrotek’s Soundguard division supplies the Soundsorber Barrier already cut to fit, for ease of assembly by Sandvik. The “tailored kit” approach pioneered by Pyrotek not only saves time but also waste. Sandvik manufactures underground loaders in capacities from 7 to 40 tonnes.
Specifiers such as Sandvik often begin their quest for the best options for their soundproofing needs by consulting the “Transport” product auto-selector at www.soundguard.com.au—one of four for different industries.