The Right Filter for Every Grinding Application

Grinding and polishing generate minute chips and particles that contaminate cooling lubricants and grinding oils. To achieve high-quality grinding results, these must be reliably filtered out. At the GrindingHub trade fair, organized by the VDW (German Machine Tool Builders' Association) in Stuttgart from May 5 – 8, 2026, KNOLL Maschinenbau is showcasing its two filter solutions: HydroPur and MicroPur®.

The KNOLL HydroPur is a hydrostatic filter capable of supplying metal-cutting machine tools with purified cooling lubricant (emulsion or oil). Due to its shallow discharge angle and high filter fineness, this filter type is particularly suitable for use in grinding processes. KNOLL offers different variants of the HydroPur, which differ in maximum filtration capacity, potential vacuum assist as well as numerous options. Thanks to the modular design using standard components, a customer-specific filter can be configured without the need for an expensive custom design.

The various HydroPur variants are the focus at the KNOLL Booth 7C50 in Hall 7 at GrindingHub 2026. The smallest model on display, a HydroPur H 250, has been presented as a complete system. This system consists of a hydrostatic filter head, a clean tank, filter fleece, supply pumps, and an optionally available unit for surface skimming.

KNOLL is demonstrating additional filtration variants and options using filter heads from the larger models. The HydroPur 400 is showcased as a cost-effective, entry-level filter featuring purely hydrostatic filtration. An optional supplementary magnetic roller is also on display. The HydroPur H 700 demonstrates simple vacuum-assisted filtration. This
is achieved via a side-channel compressor, which generates a vacuum in the filter chamber and thus enhances filtration. At the trade fair, the HydroPur H 700, with a winding unit for the used filter fleece, is on display.

While the two HydroPur variants described are already successfully on the market, the V variant, equipped with a large vacuum turbine and filter pump, will receive sales
approval shortly. At GrindingHub, visitors can get a preview of the HydroPur V 1500-E.

Thanks to the powerful vacuum pump, HydroPur V filters achieve significantly improved filtration performance. In the case of the HydroPur V 1500, this is 1,500 l/min. The H variant with the same filter head handles 1,000 l/min. Incidentally, the additional “E” in the exhibit’s product name stands for an additional continuous filter belt, which ensures reduced operating and disposal costs.

When Filter Fineness of Less Than 3 µm is Required

KF 400-E with a MicroPur®240 superfine filter and sludge concentrator.

Designed for the finest filtration, the MicroPur® superfine filter – also featuring a modular design – is KNOLL’s flagship product. It is ideally suited for use in the grinding of carbide and HSS tools. But it also delivers optimal results in the machining of castings. The MicroPur® achieves a filter fineness of less than 3 µm and manages without filter consumables thanks to its special design, which makes a significant contribution to its high degree of efficiency and sustainability.

At GrindingHub 2026, KNOLL showcases the smallest standard model, the MicroPur®120, which features two backflushable filter elements for a filtration capacity of approximately 120 l/min. The KNOLL MicroPur® product range also includes standalone units in sizes of 240 and 480, as well as individually-configured, centralized filtration systems for entire production areas.

The Click for Increased Efficiency

The Click.it Pro hardware solution, with its five freely programmable buttons,
display, and microcontroller, deserves special note.

The innovative Click.it system developed by KNOLL is also on display at GrindingHub 2026. This probe system specifically helps to reduce waste and increase efficiency in various production processes. Whether one needs to requisition materials, call the foreman, or monitor machines, Click.it ensures that information arrives right where it is needed, without detours. The system, which is available at various expansion levels, is based on a combination of buttons, sensors, software, and interfaces that collect data and transmit it to a central server. The server processes the data and transmits it to various output devices. In parallel with this, it is possible to evaluate the data, which allows for transparent process control.

KNOLL Maschinenbau
GrindingHub 2026
Hall 7, Booth 7C50

Image Source: KNOLL Maschinenbau