Low resistance when open is a key component in a manual valve. As the name implies the valves are used to manually shut the flow off, typically in pipelines when something needs to be repaired. Because the valves are hand operated they typically get far less frequent use than any other valve. If a valve needs to be used often the manual mechanism of the valve will be replaced with an actuator and as such it instead classifies as a shut-off-valve.
SEVERAL VALVES WORK MANUALLY AS WELL AS REMOTELY
Somas offers several valves that work just as well when operated manually as they do when operated remotely. The full bore SKV ball valve works great as a manual valve thanks to the very low resistance it presents when opened. Butterfly valves with their robust and “no maintenance required”-design are also a good option for a manual valve. Our ball segment valve (KVT) is mostly used as a control valve but can be used as a manual valve as well. Thanks to its open bore it doesn’t seal anything in, meaning it has an advantage as a manual valve.
Smaller manual valves come equipped with a lever for operating. For bigger valves that require more momentum to open/close, consider installing a gear unit.
Choosing a valve type depends on the process data and, like the shut-off valve, it gives a certain pipe resistance. The ball valve has the lowest pipe resistance while the butterfly valve has a slightly higher resistance. Both ball valves and butterfly valves are suitable as a manual valves.