- 1. Direct Hand Wheel.
- This method to be used when closing against low pressures and preferably only on 250mm Valves and smaller.
- 2. Hand Wheel Operated Gear Reducers.
- It is recommended that these be fitted to 300mm valves and larger and on smaller valves where it is necessary to close the valve against high pressure.
- 3. Electro-Mechanical Actuators.
- For use where fully automatic or push button control is required. These units are fitted with a manual override for use in the event of power failure. Corflex valves are easily adaptable for this type of actuator. Only suitable on Pinch Valves in low pressure applications.
(For the correct size actuator contact Corflex or their representatives). - 4. Electro-Hydraulic Actuators.
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At high pressures hydraulic actuation is the most preferred method.
The hydraulics power packs can be operated either by manual directional valves for local control or electrically operated solenoid valves for remote or PLC control.
The pinch valves are kept closed by the use of accumulators and a pressure switch that ensures the hydraulic pressure is maintained.
A manual hand pump is also fitted. - 5. Manual Hydraulics.
- For use where hydraulic actuation is required but there is no power source. This method can incorporate an automatic mechanical locking system to ensure the valve stays shut for long periods of time. This system could also make use of a mobile generator to operate valves.
- 6. Pneumatic Actuation.
- For applications where there is little or no pipeline pressure. If the valves are to be used as a control valve rather than as an isolating valve then Corflex would recommend their valve to be pre-pinched for more accurate control. The Corflex NIPPIT Pinch Valve in low pressure applications may be more suitable.