Amiad Irrigation Filters
Multi-screen, polymeric, self-cleaning filter combining Amiad’s suction-scanning technology with an innovative compact design.
• Increased reliability and durability
• Proprietary suction-scanning technology
• Large filtration area
• Polymeric housing – corrosion and fertilizer resistant
• Low water and energy consumption
• Compact design and small footprint
• Easy installation and maintenance
• Ideal for open-field irrigation, landscaping, greenhouse and aquaculture applications
• AC/DC electronic controller (optional)
How the Sigma Filter Works
The Amiad Sigma Filters are automatic filters, with multiple screens, operated by a single hydraulic turbine mechanism, with a capacity up to 280 m3/h (1,233 gpm) and with filtration degrees from 80-500 micron. Inlet/Outlet connections available: 100 mm (4”), 150 mm (6”), 200 mm (8”) diameter, and exhaust valve is 50 mm (2”).
The Filtration Process
Raw water enters from the filter inlet and passes through the multiple screens. Clean water flows through the filter outlet. The gradual dirt buildup on the screen’s inner surface causes a filter cake to develop, which creates an increase in the pressure differential across the filter system. A differntial pressure (DP) switch (hydraulic or electric) senses the pressure differential and when it reaches a pre-set value, the self-cleaning process begins.
The Control System
The Sigma operation and cleaning cycle is controlled and monitored by a hydraulic rinse controller or an electronic controller. During the self-cleaning cycle, the rinse controller operates the exhaust valve by hydraulic command. When the cycle is complete, the exhaust valve is automatically closed and is ready for the next cycle. With a electronic controller, the self-cleaning cycle is triggered by the DP switch, then the AC or DC controller switches the solenoid to open or close the exhaust valve by hydraulic comand. When the cycle is complete, the controller signals the exhaust valve to close and the system is ready for the next cycle.
The electronic controller also provides:
• Flush cycle counter
• Alerts output – low battery, DP cycle
The Self-Cleaning Process
The self-cleaning cycle begins under any one of the following conditions:
1. Receiving a signal from the DP switch – which is preset at 0.5 bar (7 psi)
2. Time interval parameter set at the controller (electronic controller only)
3. Manual start, triggered by 3 way ball valve or via electronic controller keypad
The flush water flows through the hydraulic turbine, causing the gearbox to rotate and the suction scanners to spin. The piston’s pressure-drop forces the suction scanners into an axial movement upward, ensuring that the nozzles sweep and clean the entire inner side of the fine screens.
Amiad’s Sigma Series consists of the following models:
• Sigma 4” S – for up to 120 m3/h (528 gpm)
• Sigma 6” – for up to 180 m3/h (792 gpm)
• Sigma 8” – for up to 280 m3/h (1,233 gpm)