20
Installation, Operation and Maintenance Manual
MAN 564 Rev. 6
June 2020
Operation and Use
Section 3: Operation and Use
Pneumatic connection
Figure 16
Section 3: Operation and Use
3.1
Operation Description
In the normal operating situation, the ALGA actuator is fed by pressurized gas which flows
into the relevant cylinder chamber (for example opening). The cylinder piston stroke causes
the actuator operation and the consequent valve movement to the operational position
requested (in this case to the “open” position).
Upon a demand, the closing chamber the cylinder is fed by pressurized gas and at the
same time the gas is discharged from the open chamber into the return line: the actuator
performs the closing operation driven by the piston movement, and the valve moves from
the open position to the close (safety-related) position.
