December 2020
Installation, Operation and Maintenance Manual
MAN 608 Rev. 5
Operation and Use
16
Section 3: Operation and Use
Figure 12
Section 3: Operation and Use
3.1
Operation Description
The actuator is operated by:
1.
Pressurized motor fluid.
2.
Elastic return of compression helicoidally spring.
In the first case the alimentation fluid pressurizes a chamber of the cylinder and compresses
the spring (Figure 4); this determines the linear motion of the piston and the consequent
rotation motion of the scotch yoke mechanism to which valve stem is coupled. The fluid
contained in the other chamber is discharged through the return line.
In the second case, cutting off or in case of lack of pressure to the cylinder and to the pilot
of the fast discharge valve, the opening of the latter is determined, the fast discharge of
motor fluid, the quick extension of the spring and the consequent fast operation of the
actuator. The motor fluid going out from one chamber of the cylinder partially returns in
the other chamber and partially flows through the discharge line.
For local or remote operations, please refer to technical documentation furnished
with actuators.
!
WARNING
For all the relevant information please refer to the specific documentation supplied.
