3
Installation, Operation and Maintenance Manual
MAN 571_EAC Rev. 1
September 2020
General Warnings
Section 1: General Warnings
The GPO actuator (Figure 2) is composed of one or two double action hydraulic cylinders
that, pressurized, determines the linear motion of the piston contained in it.
The linear motion of the piston is transformed into rotation by a scotch yoke mechanism.
Gas sampled by the line, pressurizes oil contained in one of the two gas-hydraulic tanks
and then the one of the cylinder determining the drive of the actuator.
A peculiar feature of GPO actuator is its great flexibility of use obtained by the choice of
a manufacturing solution easy, solid and without parts in motion.
The expected lifetime of actuator is approximately 25 years .
Figure 2
Identification of Actuator Parts
1.3
Introducing the Actuator
The gas hydraulic GPO actuator is designed and used for the operation of quarter-turn
valves (ball valves and plug valves) installed on gas transportation lines, in compressor
stations and everywhere a high pressure gas supply is available.
Hydraulic manual override
Gas-hydraulic tanks
Flow-regulator valves
Pneumatic
control group
Scotch yoke mechanism
Hydraulic
cylinder
1.4
Data Sheet
Supply fluid
Natural gas / nitrogen /air
Operating temperature Standard: from –20 °C to +80 °C
Optional: from –60 °C to +80 °C
Supply pressure
Standard: ranging from 7 to 100 bar.
Optional: minimum pressures starting from 3,5 bar, maximum
pressure up to 160 bar. For higher gas supply
pressure, a pressure regulator is foreseen.
