ISO standard valves

The Norgren five-port valves can now incorporate twin 3/2 valves in the valve body, effectively having two three-port valves in a five-port body yet still conforming to ISO 15407. This enables water treatment plants to control twice as many spring return actuated process valves in an ISO valve. For example, 20 activated valves could be controlled by 20 3/2 solenoid valves that are mounted in a 10 station valve island. Alternatively, a combination of twin 3/2 valves and standard 5/2 valves can be configured enabling double acting activated valves to be controlled.

The VS range of ISO solenoid valves is available with standard nitrile rubber seals, however a glandless spool and sleeve technology may be more appealing to water treatment plants. The glandless valves are unique in design in that they use a hardened anodised teflon-coated spool and sleeve that has no dynamic seals. The spool operates on an air bearing principle that offers several benefits over conventional nitrile seal valves. The teflon-coated hardened alloy spool and sleeve enables the valve to run lubricated or unlubricated providing over 100 million cycles.

The benefit in water treatment plants is that the teflon-coated spool valve can remain unoperated for days. In these circumstances, condensation can accumulate in the airline and valve, yet it is unaffected on start-up due to the teflon coating on the spool and sleeve.

An option that can be incorporated into VS series ISO 15407-2 valves are valve isolating blocks. The isolating block sandwiches between the solenoid valve and the manifold base. Should a valve require replacement, the air supply can be isolated to that individual valve station. All other solenoid valves can continue uninterrupted function in the water treatment plant.