22
September 2020
Installation, Operation and Maintenance Manual
MAN 571_EAC Rev. 1
Section 3: Operation and Use
Operation and Use
Section 3: Operation and Use
3.1
Operation Description
The supply gas pressurizes oil contained in the gas-hydraulic tank relevant to the operation
to carry out (opening or closing) (Figure 18).
Oil, (Figure 20), arrives to the manual hydraulic control group and pressurizes a chamber of
the cylinder: this starts the linear motion of the piston and the consequent rotation motion
of the scocth yoke, to which the valve stem is coupled.
Oil, discharged from the chamber of the cylinder, flows in the second tank going through the
manual hydraulic control group and the flow control valve placed under it, that regulates the
operation time being carried out (Section 3.6).
When the operation is over, the pressurized gas exhausted, is discharged through the valves
placed in the control group. This allows having the actuator not in pressure except during
the execution of the operation.
