The SAF series are automatic filters with a self-cleaning mechanism driven by an electric motor. The SAF filters are designed to work with various types of screens in filtration degrees from 500 to 10 micron.
The water enters through the inlet pipe into the coarse screen from outside in, and through the fine screen from inside out. The "filtration cake" accumulates on the fine screen surface and causes head loss to develop. The coarse screen is designed to protect the cleaning mechanism from large dirt particles. It should not accumulate large quantities of suspended solids and is not cleaned automatically.
The SAF filter will start the self-cleaning process when the pressure differential across the screen reaches a pre-set value or a predetermined lapse of time.
Cleaning of the filter element is carried out by the suction scanner, which rotates in a spiral movement while removing the filtration cake from the screen, and expels it out through the exhaust valve. The rotation of the scanner is operated by a 2-way (fwd/rev) drive unit that is attached to the scanner by a threaded shaft, providing the linear movement. The exhaust valve is activated for the duration of the cleaning cycle by a 3-way solenoid. During the self-cleaning process, which takes approximately 35 seconds, filtered water continues to flow downstream.