In most of the applications, for pumping of water and wastewater, check valves are quite commonly used. They are meant to automatically open when pumps are running, then get closed to prevent any reverse flow during the time pumps are not running. These kinds of valves can minimize energy consumption, also protect your pumping system from damages or pressure surges from reverse flow.
Among sanitary replacements parts mainly two kinds of check valves are usually found in most of the system.
- Lift check valves
You can usually find them being used in mostly high-rise buildings, water/wastewater applications and industrial or power plant applications. They are economical and reliable and have no moving parts. Over a period of time, they may have high cost of energy as the disc remains during the flow stream operation.
- Silent check valve
Because of their quite closure it is called silent check valves. Flow will push the disc for allowing forward flow. After pump is stopped, compression spring will push disc into its seat before flow reverse.
- Nozzle check valves
Similar to the above and meant for industrial, power and high-pressure applications.
- Ball check valve
These valves are rubber coated ball which moves in or out as flow moves reverse or forward. They have quite simple operation, are compact and also economical.
- Swing check valves
Swing checks are also used in water/wastewater pumping systems. They are readily available at relatively low cost. They are also automatic and guided by direction of flow. They are also available in few different configurations:
- Dual-disc
This check valve has wafer body design with two D-shaped discs which rotate as the flow enters into the valve. It is however not recommended for any wastewater applications. Also, it is susceptible to wear and vibration.
- Traditional swing check
This valve has seats of metal or resilient with 60 to 90ᵒ swing.
- Tilted disc check-valve
The difference between above valve and this type of valve is that it allows flow on disc’s both sides. Due to this, it can allow for too low head loss.
By reading the above, you can choose the right kind of check-valve for your application. Maybe you can get even better one than all above. Before making any changes, you must discuss about the pumping system with any engineer who is experienced in all kinds of check valves. It is quite possible that they can come out with much smarter option for your application.
