Knoll: The right filter technology for every grinding process

For high-quality grinding results, optimised cleaning of grinding oils and other grinding oils and other cooling lubricants (coolants) is essential. KNOLL Maschinenbau offers customised filter solutions for for a wide range of grinding applications. The wide range can be visitors to GrindingHub 2022 in Stuttgart at the KNOLL stand (Hall 7, Stand 7C20). stand (Hall 7, Stand 7C20): the 10 MicroPur® ultra-fine filter, the individually configurable HydroPur configurable HydroPur hydrostatic filter, the VLO vacuum filter and a and a liquid centrifuge for bypass operation.

The finer the cutting, the higher the proportion of ultra-fine particles in the grinding oil or coolant. oil or coolant, which in turn jeopardises the quality of the machining result. quality of the machining result. Preventing this is the the task of the modular MicroPur® ultra-fine filter from
KNOLL Maschinenbau, Bad Saulgau. It is ideally suited for tool grinding of carbide and HSS. But it also delivers the best filter results in cast iron machining. The MicroPur® 20 achieves filter finenesses of less than 3 μm and, thanks to its special design, does not require any filter consumables, which contributes significantly to its high cost-effectiveness.

At GrindingHub, KNOLL will be showing the standard MicroPur® 240/900 model – together with the capacity-matched, integrated AK5 sludge concentrator, which ensures automated sludge discharge. In addition to such standardised systems for single or multiple machines, KNOLL offers individual central filter systems based on MicroPur® for entire production areas.

Anyone who needs a stand-alone cleaning unit for grinding and wants to configure it themselves as required is well advised to go for the HydroPur hydrostatic filter, which KNOLL is presenting at a trade fair for the first time. Such a filter unit has a modular design. It essentially consists of a tank and filter top with a fine filter fleece, which, in combination with the hydrostatic principle, separates liquid and chips. Pumps, coolers etc. can be added as required – for the simplest equipment up to the full version, which then meets even the most demanding requirements.

Operation of the HydroPur is also simple and very intuitive. This is because KNOLL uses its new SmartConnect operating concept for this, in which a small industrial PC is connected to the system PLC via a 7″ touch display. SmartConnect also has app connectivity, so that the operator can also access the filter system with mobile devices such as a smartphone or tablet, visualise statuses and check and change parameters.

KNOLL will also be presenting the VLO vacuum filter system, which is particularly popular for profile grinding with machining oil. Due to the simple scalability of such a filter system, it can be used locally for a single machine or centrally for several machines. Without the use of filter aids, the VLO vacuum filter system achieves clean oil as well as pure, dry concentrate.

Last but not least, KNOLL will be presenting an automatic liquid centrifuge CA 100 at GrindingHub, which is of great importance in grinding oil cleaning with its proven technology. In many filter systems, it takes over bath maintenance in the bypass and prevents the concentration of fine particles. Also for
retrofitting of existing systems, this systems, this system technology is also popular.

This is how the KNOLL HydroPur filter system, presented for the first time at a trade fair, works:

The lifting pump of the machine tool or a lifting station conveys the contaminated coolant into the HydroPur’s inlet box and from there onto the filter fleece. Due to the hydrostatic pressure, the fleece allows the coolant to pass through, but retains chips and foreign matter. These form a filter cake that decreases in
which, with increasing thickness, causes a decreasing volume flow through the filter surface. The level of the dirty liquid rises to a defined height, then the belt drive switches on and conveys the filter fleece a little further. Clean filter fleece then reaches the the filter surface, the volume flow increases and the level of the dirty level of the dirty liquid decreases again.

After the dirty liquid has been discharged, the fleece with the the filter cake adhering to it runs over a drying section before it enters the into the collection container. KNOLL offers an optional unit for the used fleece in combination with a scraper, which is previously scraper, which separates the filter cake into the container beforehand. The cleaned coolant flows into the clean tank. From there, up to up to three pumps supply the machine tool with cleaned COOLANT.

For more information, please visit: https://www.knoll-mb.de/en/news