Portable Filter Unit for Hydraulic Oil
Oil filtration system, filter cart, and filling unit in a single mobile unit
A mobile filtration unit handles hydraulic oil maintenance right where the machine is located: filtered refilling, bypass filtration during operation, and draining of used oil—without the need for a permanent installation or an on-site electrical connection. Depending on regional terminology, such devices are also known as oil filtration systems, filter carts, or mobile filtration units.
FILCOM supplies the devices from KNOLL Hydraulics as an authorized distributor—either with factory-integrated oil purity monitoring or as a base unit for later retrofitting.
Mobile filter units for hydraulic oil maintenance
Stationary filter systems are cost-effective for systems with high oil volumes and constant loads. Where multiple machines with smaller tanks are being serviced, a system is flushed only occasionally, or fresh oil must be pre-cleaned before filling, a mobile unit is the more economical solution: It is hooked up as needed and is then available for the next machine.
Overview of Mobile Filter Units
| Model | Item Number | Volume flow | Filter Fineness | Oil Purity Inspection |
|---|---|---|---|---|
| KNOLL 3-in-1 Fill/Bypass Filter Unit | 17-0002671 | 6–36 l/min | 3–10 µm | retrofitable |
| KNOLL 3-in-1 Refill/Bypass Filter Unit + Particle Monitoring | 17-0002590 | 6–36 l/min | 3–10 µm | integrated |
| KNOLL Particle Monitoring Kit | 17-0002672 | – | – | Retrofit Kit |
Which device is best for which use?
If the unit is used primarily for filling and transferring, and oil purity is assessed anyway by a laboratory or an existing measuring device, the basic model is sufficient. If the purity class needs to be readable directly on the unit while it is in operation—for example, to stop the flushing process as soon as the target value is reached—the model with integrated particle monitoring is the right choice. Those who initially purchase the basic model can add the measurement technology later using the retrofit kit.
As a rule of thumb, the filter fineness should be 10 µm for general industrial hydraulics, and 3 µm to 6 µm for servo and proportional systems, as well as for the preliminary filtration of fresh oil.
How to Choose and Order Filter Elements Correctly
The filter elements are wear parts and are not included with the units. They are selected when placing an order in the “Accessories” section of the respective product page—only elements approved for use with the unit are listed there, so there is no risk of mixing them up. These same elements are later used as replacements when changing the filter.
The following applies to selection: Each element covers one filter grade, and changing the filter grade is done by swapping out the element. In practice, users who employ the unit for both pre-filtration of fresh oil and continuous bypass filtration will find that keeping two filter grades on hand offers the greatest flexibility. A water separator filter can optionally be installed in place of the other filters if moisture enters the oil.
Consulting and Custom Designs
Do you need a different filter fineness, couplings adapted to your machinery, or labeling with your company logo? Contact us—we’ll check the feasibility directly with the manufacturer.