Creating Complete Coolant Systems with Electrostatic Mist Extraction
Pete Mangan, MD here at oelheld UK, recently spoke with Grinding & Surface Finishing about the work we’ve been doing with our mist extraction partners, indusa GmbH and why we love their systems for our customers. Get the lowdown in your copy of Grinding & Surface Finishing (pg.32-33), or read on here…
Fluid and filtration specialists oelheld UK and air purification experts indusa GmbH, are celebrating the anniversary of their official partnership delivering custom-build centralised and individual oil mist extraction systems for UK toolmakers and precision grinders.
Keen to support customers with all elements of the coolant journey, the partnership positions the UK firm to offer complete fluid solutions incorporating, correct coolant selection, filtration design and enhancement, strategic maintenance planning, Local Exhaust Ventilation testing and now mist extraction.
Pete: “We want to provide customers with a single point of support for all elements of their fluid systems and the addition of mist extraction to our portfolio means we can do just that. Having worked with indusa on a number of projects we knew the team, the quality of their systems, and that our respective technologies complement each other well so it seemed like a very natural partnership, especially as their electrostatic Elstar range of systems are so well suited to the grinding processes many of our customers are using.”
Mist Extraction Requirements for Grinding Processes
Grinding oil or coolant mist is a natural by-product of the cooling process, created when the hot workpiece causes coolant to evaporate as it hits the material, forming a steam or mist after condensation. The high-speed rotational movements during machining can also throw oil into the workspace, causing a continuous spray of fine or oil droplets.
To effectively filter out this oil mist from the machine’s exhaust air, the mist extraction system must be able to separate oil mist particles (<1μm in size) and maintain an airflow turnover of approximately 300 circulations per hour, being the recommended flowrate for grinding processes.
Why Consider an Electrostatic System for Grinding Processes?
For Performance
Indusa’s Elstar range is designed to meet these challenges. Using innovative ionization technology, oil mist particles are separated and collected by electro-charged metal plates after having been charged themselves as they enter the system. This technology enables the system to handle exceptionally small particle sizes (from 0.01μm), filtering 99% of oil mist particles.
For Productivity and Cost Savings
Compared with conventional mechanical filter systems, the pressure loss in an electrostatic system is much lower, requiring significantly less fan/ventilation power and therefore offering considerable energy saving costs.
The charged metal plates of an electrostatic system replace the traditional paper, fleece or mesh filter media and do not require replacing, reducing consumable costs considerably.
Collected oil particles can be returned to the fluid filtration system to be reused, reducing waste.
Potential for heat recovery to save energy costs and reduce CO² emissions.
For Protection
Oil mist particles can be seriously damaging for inventory stock, the workshop environment, and worker’s health. The sticky film created by oil mist particles can present a slip hazard, a build-up of oil mist in the machine can increase the potential for fire, and inhalation of oil mist particles can cause a number of serious lung diseases such asthma and other respiratory problems (e.g. ‘heavy metal lung’). The HSE is becoming increasingly proactive around the subject of air quality. For instance, COSHH regulations require exposure levels to be controlled and most LEV systems to be tested every 14 months.
Pete: “This makes regular testing and maintenance crucial to the performance of extraction systems. Many grinding machines are supplies with pre-installed extraction units but, as these tend to be top mounted, accessibility and maintenance can be difficult which can result in clogged filter inserts or incorrect airflow rates that don’t de-mist the machine thoroughly enough - we would encourage anyone who has an extraction unit that hasn’t been recently serviced to arrange a test.”
Since officially partnering in 2018, indusa and oelheld have successfully delivered several central system installations incorporating both new and existing machine-mounted units, and several individual unit installations to replace pre-installed mounted units that had fallen into disrepair. The partners are currently working on a proposition which is exploring combined heat recovery from both oil filtration and mist extraction systems. Pete: “This is a really interesting project which is pushing us to see just how far we can integrate our respective technologies in a more holistic approach that incorporates multiple elements of fluid systems. If successful, we believe this system design could reduce carbon emissions by over 100 tonnes per year for a standard factory environment, with significant energy cost savings.”