NEOPERL Catalogue 2016 - Page 38

Check vALvES – CONSTRUCTION and function
The nominal diameter of the pipeline system is the determining factor when choosing a check valve cartridge . The aim is to reduce the pressure loss through the check valve cartridge to a minimum ( EN 13959 ). The pressure lost through a NEOPERL ® check valve cartridge is very low . Open cage constructions have lower pressure loss than closed body constructions . The valves are available with different springs varying in stiffness in order to comply with international standards .
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1 Housing
2 External seal
3 Closing system – Spring – Plunger & seal – Guidance
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3
Operating principle
Static state ( no flow ) The check valve is closed . The spring presses the cone into its seat and keeps the valve closed .
Dynamic state ( flow ) The pressure of the water is higher than the spring pressure . The cone is pushed out of its seat and allows the water to pass .
Backflow ( flow in the opposite direction ) If the direction of flow changes as a result of an increase in pressure downstream of the valve ( backflow ) or a reduction in pressure upstream of the valve ( backsiphonage ), the spring allows the cone to snap back into its original position , closing the inlet side of the valve to prevent water flowing back .
38 | Check valves
Check valves – construction and function The nominal diameter of the pipeline system is the determining factor when choosing a check valve cartridge. The aim is to reduce the pressure loss through the check valve cartridge to a minimum (EN 13959). The pressure lost through a NEOPERL® check valve cartridge is very low. Open cage constructions have lower pressure loss than closed body constructions. The valves are available with different springs varying in stiffness in order to comply with international standards. Housing External seal 3 Closing system – Spring – Plunger & seal – Gui F6P 0  W&Fr&6P7FF27FFRfrFR6V6ffR266VBFR7&r&W76W2FR6RFG26VBBVW2FRffR66VBࠤG֖27FFR*frFR&W77W&RbFRvFW"2vW"FFR7&r&W77W&RFR6R2W6VBWBbG26VBBw2FRvFW F72ࠤ&6frfrFR6FRF&V7F␤bFRF&V7Fbfr6vW22&W7VBb7&V6R&W77W&RFv7G&VbFRffR&6fr"&VGV7Fখ&W77W&RW7G&VbFRffR&66vRFP7&rw2FR6RF6&6FG2&v6F66rFRWB6FRbFRffRF&WfVBvFW"fvp&6ࠣ36V6ffW00