OLGAS-H
– High pressure spring return hydraulic actuator
Use and maintenance manual
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Pag. 20
Contents may change without notice
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.
For all the relevant information please refer to the specific
documentation supplied.
