Media such as hydraulic oil, water for cooling and emulsion can carry contamination and transmit it throughout all of the components of a system. Debris is the major enemy of all hydraulic and other oil systems. By controlling the level of dirt in the oil, it is possible to avoid more than 70% of faults in the performance of the oil system, slow its ageing and need for early replacement.

Machinery filters are subject to harsh working environments, as they usually have to filter at a high pressure and pass a large amount of oil, where there is often an occurrence of a cyclic change in working pressure. Therefore system filters can only partially purify the oil, which is not sufficiently effective.

The basic conditions for good micro-filtration are a continuous gentle flow of oil at a low pressure, where the oil that has passed through the micro-filter returns to the main oil flow or into a reservoir. It is on these principles that micro-filtration in a by-pass circuit is based.


Each circuit, hydraulic component or system require a certain purity of oil and that needs to be monitored during the filtration. Guidelines for selecting the required grades of oil purity:


  • Moisture in an oil system is inevitable. Most often it penetrates into the reservoir due to defects in the cooling system. Additionally, it may be the result of condensation caused by temperature changes. It can also enter the oil fill due to contact with the surrounding air.
  • Moisture in an oil system will cause corrosion and eroding of the surfaces of the components, and the water will slowly penetrate into the pores of the metal, which results in the metal ageing.
  • Water will also create conditions for microbial life which consequently causes deterioration and oxidation of oil.



  • HFCs are non-flammable hydraulic media intended for use in high temperature areas and near open flames. Because of this they are applied in production plants for aluminium and aluminium alloy casting.
  • Filter machines for the filtration of HFC media are made from water-glycol resistant materials as is the material of the filter elements.


All production systems including CNC work stations are subject to constant pressures from conflicting demands; a higher quality of output versus lower production costs. A significant contribution to the optimisation of these criteria is the timely and professional maintenance of media that are used in metal processing such as cooling and lubricating emulsions and cutting oils.

The mobile and multi-function device SF 500 is exactly intended for these purposes, cleaning machines of emulsion, cutting oil and sludge. It features four functions and acts as:

  • a suction device for liquids, chips and grinding sludge from the tank
  • a filter device with a belt filter
  • a high-pressure washer using purified emulsion to clean machines
  • a separator of free oil from surfaces

It is equipped with extensions for the cleaning of hard to reach areas such as narrow gaps and corners. A pump returns purified liquid to a clean tank.