Let us now analyse another accessory of the plate filter presses: the optional of the automatic washing group.
The automatic washing unit is a portal structure (which is installed above the frame of the filter press) in which a trolley runs.
This trolley carries a washing unit formed by a high-pressure pump and suitable nozzles whose function is to “mechanically” clean (wash) the canvas by means of a high-pressure water wash.

This serves precisely to clean any local residues of sludge.
The carriage runs horizontally along the entire length of the machine and can be raised and lowered to clean the fabric along its entire vertical development.
This is precisely a high-pressure mechanical washing – up to 100 bar which is used to clean the cloths if, after a few filtrations, dirt remains between one cloth and another (the accumulation of material between one cloth and another, if it persists over time, it can compromise the functionality of the machine).
In fact, if there are too many sludge residues that are not cleaned between one plate and another, the same effect is obtained as when there is no flatness between the filter plates.
This risk – especially in long machines – is that the frame of the machine bends in the long run due to excessive misalignment.
The washing pressure can also be lowered and pressures can even be around 40 bar.