There is an option on the Sandvik MB670 Bolter Miners of an on-board dust extractor. This system helps to reduce the amount of dust that operators are subjected to and also provides the required ventilation for the cutting area of the Bolter Miner.

With operators’ health in mind, it was decided that efforts should be made in order to reduce the level of noise produced by these filtering units. As a consequence, two solutions were created. The first is an outlet silencer or ‘sound absorber’, which can be fitted to the existing filtering unit, and the second is a whole new dust extractor unit which also includes an elastic mounted fan.

Filtering Unit with Sound Absorber

The shape and dimension of the sound absorber components were calculated to match the specific frequencies of the fan unit.

New filtering unit(mountable on a Sandvik Bolter miner)

The fan unit (114) of the dust extractor system is elastically mounted in a way that the vibrations are isolated from the scrubber box (113) as well as from the mounting bracket (109). In addition optimization of airflow optimizations was also achieved.

The results achieved during the testing of both systems are significant. The noise produced by the former, existing dust extractor was monitored without the silencer and then subsequently with it. The final test was carried out using the new dust extractor system. The sound is measured in decibels (dB (A))* and the systems were tested from a number of operator positions, as explained below:

1 = Operator: Platform right hand side, front
2 = Operator: Platform right hand side, rear
3 = Operator: Platform left hand side, rear
4 = Operator: Platform left hand side, front
5 = Measurement point at fan unit

Compared to the existing, former system, when the silencer was added to the dust extractor, the noise level was reduced by 4 to 5 dB (A), a notable improvement, however when the new dust extractor system was tested, the results were remarkable. A reduction of 8 to 10 dB (A) was achieved, dependent on the operator’s position.

Both the new outlet silencer and the entire new filtering unit are patented by Sandvik. If you are interested in receiving further details on these patents, please contact us.

Despite the on-board filtering unit being an option offered by Sandvik Mining for their Bolter miners, nearly all customers choose the system for their machines, in fact all Bolter miners being delivered to China are fitted with the brand new filtering unit. Customers not only appreciate the benefits of suppressing and extracting dust but also of keeping noise to a minimum for both operator health and productivity.

If you would like to find out more about the Sandvik filtering units for Bolter miners, or any other Sandvik products, please get in touch.

*dB (A)

A-Weighted decibels, abbreviated here as dB (A), is the most common weighting scale that is used in noise measurement. It follows the frequency sensitivity of the human ear at low levels and is a good predictor of damage risk to the ear. A-Weighting scaled sound meters filter out low-frequency noise that they measure, which is similar to the response of the human ear.