• Krone Filtertechnik
    and Profluid - backwashfilters
    Made in Germany

RELIABLE PROTECTION FOR MACHINERY AND THE ENVIRONMENT We would be delighted to provide you with a custom-built solution that meets your specific needs!

Gapfilter G 1" DN 50 DN 100 / DN 200

for the filtration of low and high-viscosity media

made from VA

Krone Gap-Type Tube Filter G1/2"

Alternative to Mahle / Knecht AF71L


The medium to be cleaned flows into the housing via the filter inlet and flows through the gap-type tube from the outside inwards. All impurities in the medium that are larger than the gap width are retained on the gap-type tube surface. The coarser dirt particles either fall down into the lower part of the housing or form a filter cake on the outside of the gap-type tube.

Dirt scraping
By using a geared motor, the gap-type tube surface is moved past a fixed scraper and the filter cake is scraped off. The filter cake sinks inside the housing and can be removed as required through the sludge drainage.

For easy disposal of filtered solids, a drying unit can be installed downstream.


Dirt particles of a certain boundary grain size are not caught by the scraper.

In conventional gapfilters, these particles – es- pecially those with gap widths ≤ 100 μm – can settle in the gaps and, depending on the operating conditions, may quickly lead to clogging of the gap-type tube.

Through the action of the backwash chamber, it is possible to flush the boundary grains out of the gap-type tube. The backwashing chamber acts across the entire gap-type tube length. When the backwash line is opened, the medium flows opposite the normal direction of flow into the non-pressurized backwash chamber and is discharged to the outside.

The backwash process can be controlled according to company-specific requirements. Control variables can be operating hours, units of time, as well as an increase in the differential pressure between the raw side and clean side of the filter. The operating pressure and preset backwash volume determine the effectiveness of the backwash. The patented combination of dirt scraping and backwashing in the case of the Profluid represents an effective form of cleaning the gap-type tube during operation.

Operating principle

When it comes to increasing the service life of machining or process fluids, automatic filters such as Profluid or gapfilters are a truly expert choice.

They are suitable for the filtration of low and high-viscosity media, making it possible to use them in almost every industrial sector. Gapfilters can be cleaned by mechanical means during operation. Profluid is an automatically cleanable filter system with a design based on gap-type tube technology.

Its combined cleaning principle of backwashing plus mechanical scraping makes it particularly efficient for filtration applications where a wide variety of types and sizes of particles are to be filtered from a fluid. Its mode of action has proven to be highly efficient at required gap widths below 100 μm.


Spaltfilter Video


  • Very easy to maintain
  • Highly economical
  • With option of fully automatic cleaning during operation
  • Proven thousands of times over!


  • Polyurethane, insulating materials of all kinds
  • Solvents, adhesives, plasticisers
  • Flooring materials, tar products, epoxy resin
  • Cooling lubricants, emulsions
  • Food industry
  • And much more

Product inquiry

To find the best and most cost effective solution for your application, please fill in our questionnaire and it as a fax to +49 (0) 4202 9769-11 or as an email to spaltfilter@krone-filter.de.

  Download Questionnaire


Human verification
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