Dust Extraction System – Investment Casting

An Investment Castings company contacted Ducting Express as their current extraction systems in place did not comply with legislation and would fail any COSHH examination to HSG 258 standards. A recent exposure test for Workplace Exposure Limits (WELs) highlighted the problem with their current dust extraction system and action was deemed as paramount. 

Following the initial enquiry our experienced design engineer conducted a site visit to meet with the customer, take a look at their current dust extraction and discuss their requirements going forward. 

The customers existing system comprised of 2 inline tube fans on 2 separate ducting systems. The fans were trying to control dust produced from a process with no filter capture of the hazard in evidence. The types of fans being used would be generally used for conveying air and were not suitable for conveying dust. The inline tube fans are rated at approximately 950 m3hr and were not producing enough airflow to convey process dust effectively. The extracted dust was then being discharged to high level but due to its particle weight, visible evidence around the surrounding roof area of the stacks showed that it was not being controlled effectively and not compliant with HSE COSHH guidelines.

With all the information gathered during the site visit, our experienced dust control designer proposed to strip out the existing extraction system and supply & install a new shaker type dust extraction unit, flexible extraction arms and ducting which would remove the dust produced from the process in the shelling area. 

One of our DE 25M auto shaker filtration units with a 7.5kw motor was installed externally  to the side of the building. From the extraction filter, new suitably sized ducting would connect to a total of three two meter flexible extraction arms. These would be mounted on the rear wall; one will accommodate two ceramic mixers; one for two secondary mixers; and one for a primary mixer. Two new hoods would be fitted to the front of a spinning drum where most of the dust was not being controlled effectively, this would connect to the main duct. The system was designed as an either/or system and any 2 hoods were to be used at any one time with shut off dampers fitted to hoods. The minimum airflow volume the system would need to produce in order to effectively extract the dust was approximately 2600 m3hr.


The duct layout was designed to give efficient airflow throughout the system, ensuring that the emissions of hazardous substances at the extraction points were controlled to below the occupational exposure limits.

 

The dust extraction system installation
The system was installed over a three day period followed by a visit by our LEV commissioning engineer who completed a COSHH test to provide the customer with legal documentation for their health and safety records. During the commissioning visit the customer requested that one of the fume extraction arms were shortened to suit their processes better.

If you are having a similar issue with dust in your workplace the team at Ducting Express can help you to find the perfect dust extraction solution for your business. Contact us on 01455 616 444 today.