Gefa TYPE HYDRAULIC Control Unit

The automatic flushing cycle described below takes a few seconds and does not interrupt the supply of process water. Water flows from the inlet through the coarse and fine screens to the outlet. At a pre-set pressure differential (0.5 bar —7 psi), the rinse controller activates the piston and opens the flushing valve. The water from the rotor chamber flows out the drain. The pressure in the rotor chamber drops, releasing a strong flushing stream that flows through the filter.

This drop in pressure and corresponding release of the backflush stream create suction on the nozzle tips. This effect actuates spot cleaning directly in front of the openings of each nozzle on the inner surface of the fine screen. The water and particles passing through the hydraulic rotor cause the dirt collector to rotate, and the piston moves in an axial direction to the opposite end of the filter.

The combination of rotational and axial movement of the dirt collector assembly ensures that the nozzles sweep the entire inner surface of the fine screen.

When the first stroke is completed, the flushing valve closes and after a very short interval the rinse controller activates the second backflush stroke. The dirt collector assembly spins, moving with the piston in the opposite direction and returning to its original position.

This self-cleaning process takes between 8–15 seconds, depending on the operating pressure.