Vacuum filter / Negative-pressure filter

Suction belt filter SAFI-C (fleece filter)

The SAFI-C filter is used for large flow rates. This high-performance filter can be used as a stand-alone filter up to a capacity of max. 9000 litres per minute. This filter system is the core element of central systems.

Their advantages

  • Suitable for the largest flow volumes
  • Compressed dirt cake, dry, landfillable
  • Robust durable construction
  • Energy-optimised by FU control

Short info

  • For large central systems
  • Precise lateral seals
  • Many varieties of fleeces can be used

Robust, durable and highly efficient

Robustness and durability are the outstanding features of this filter. Especially for central systems, its qualities such as reliability are enormously important. Due to the exhauster, the filter is a special drying unit with which very dry filter cakes can be produced. High-quality filtration finenesses can be achieved by using different fleeces.

By using frequency-controlled components, the energy requirement is matched perfectly to the system output.


The filter housing consists of a high-quality welded steel construction. A transport chain carries the filter fleece through the filter bed. An exhauster generates the negative pressure in the vacuum chamber and thus significantly increases the flow rate per square feet (square metre) of filter surface. The cleaned cooling lubricant enters the clean chamber from where it is discharged into the clean tank by means of a pump. The functions, triggered by float switches, are controlled by a control box.


The medium is calmed and fed to the filter by the inlet distributor, flows through the filter medium and reaches the vacuum chamber (clean chamber) cleaned. The filter discharge pump sucks the medium out of the vacuum chamber and conveys it into the clean tank.

The exhauster creates a negative pressure in the vacuum chamber. This negative pressure supports the flow rate considerably and results in a better utilisation of the filter medium due to a higher dirt cake build-up. The built-up filter cake provides an additional, high-quality filter layer and thus improves the degree of filtration.

As the filter aid becomes increasingly dirty, the liquid level on the dirty side of the filter rises. The fleece pre-stroke occurs at a preset liquid level. The filter cake discharged with the fleece is dried additionally by the exhaust air of the exhauster. The filtration process is not interrupted during the fleece pre-stroke. An additional buffer tank for intermediate storage of the dirty cooling lubricant is not necessary!

The built-up filter cake is a valuable filter aid and significantly improves the degree of purity. Due to the short stroke steps, this “precoat medium” is almost completely preserved and the degree of purity remains unchanged.


Energy efficiency

Precise sealing

Made in Germany

Process safety

Picture gallery

Data sheet

Standard sizesSAFI-C3.6SAFI-C4.1SAFI-C5.1SAFI-C6.1SAFI-C7.1SAFI-C8.1SAFI-C8.6SAFI-C9.1SAFI-C10.1
Mounting dimesion L x W3340 x 16453710 x 16454450 x 16455190 x 16455930 x 16456670 x 16457040 x 16457410 x 16458150 x 1645
Height 230023002300230023002300230023002300
Weight approx. (kg)237025302810325035303810396041004380
Volume approx. (litres) 2730329044105300665077708330889010010
Flow rate max. (l/min) emulsions*310036004500540063007200760080009000

*Definition of flow rate: Emulsions and aqueous media approx. 1 mm²/sec at 20 °C and oils up to 15 mm²/sec at 20 °C.
The maximum flow rate of the filter is indicated; depending on the machining process and the degree of contamination, the flow rate may be lower.

Subject to technical changes in the interest of progress.

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