Residual Fume and Heat: Die-casting Manufacturer
The Client
A die-casting manufacturer of parts for the automotive industry was relocating into a new manufacturing facility and the company’s managing director and head of QHSE and compliance saw the move as an ideal opportunity to improve the QHSE for workers. The relocation formed part of the company’s growth strategy and enabled the company to automate and increase its production output.
The Challenge
Auto Extract Systems were tasked with proposing and installing a comprehensive LEV (local exhaust ventilation) system in the new manufacturing facility to safely capture and remove the dust, fumes and heat that were being emitted into the workplace’s air from the manufacturing process for the die-casting manufacturer. The LEV systems were installed to ensure the manufacturing plant meets stringent operational requirements to work strictly in accordance with HSE’s ‘HSG258: Controlling Airborne Contaminants at Work – A Guide to Local Exhaust Ventilation (LEV)’ guidance.
The Solution
Secondary General Ventilation LEV System
Three solutions were proposed to the client to provide a comprehensive LEV solution for their two manufacturing areas. The first two systems were to provide general ventilation (in the area where twenty die-casting machines were located) in the form of a wrap-around general ventilation system. This kind of system captures rising, residual lead fumes and heat given off from the machines to create a low-level, general ventilation extraction system.
The two systems featured dampen-able grilles that were tactfully located above each of the machines and could be angled towards the naturally rising plume. In addition, deflector plates were also installed on either side of each grille to increase the capture area. The grilles were placed along a galvanised common duct that ran back to a comprehensive centrifugal fan.
Direct Connection LEV System
The tertiary LEV system was, a direct connection system, which was located in another manufacturing area and featured three points, two that were fixed directly to 160mm spigots located on the side of the machines existing perspex cabinets, whilst the third connection point was to a 200mm spigot. Dust captured in this system were conveyed back to a reverse-pulse filtration unit, which featured the latest innovative filtration technology; capable of self-monitoring, self-cleaning and filtering up to 99.9% efficiency. The filter specified for this LEV system had the capacity for two filter cartridges and gives the filter unit a total filter surface area of 39m2 (19.5m2 per sleeve), however, the modular system is capable of accommodating up to eight filter cartridges.
All three systems designed to comply with the latest HSE guidance of >0.5m/s at the effective distance and were also designed for 100% utilisation (all points open at once). Each point was connected to a common duct that was run outside to a centrifugal fan (via a modular reverse pulse filtration unit in the third system) and turned upwards to be vented to atmosphere through high-velocity cowls, as per HSE guidance.
Auto Extract Systems continue to maintain the LEV system installed with an annual LEV Testing. LEV tests are a legal requirement and should be tested at least once in a 14-month period for compliance with HSE standards; they often form part of a company’s insurance requirements too.
