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June 2021
Installation, Operation and Maintenance Manual
MAN 689 Rev. 6
Operation and Use
Section 3: Operation and Use
3.1
Setting of the Angular Stroke
It is important that the mechanical stops of the actuator (and not those of the valve) stop
the angular stroke at both extreme valve position (fully open and fully closed), except when
this is required by the valve operation (e.g. metal seated butterfly valves).
The travel stop screws are screwed into the end flange of the pneumatic cylinder,
depending on actuator different configuration (i.e. spring to open or spring to close),
and spring cartridge. The setting of the open valve position is performed by adjusting the
travel stop screw on the left side of the actuator. The setting of the closed valve position is
performed by adjusting the travel stop screw on the right side of the actuator.
3.1.1
Travel Stop Screw Screwed on the End Flange
of Pneumatic Cylinder
For the adjustment of the travel stop screws, proceed as follows:
1.
Remove the protection plug (t) with proper wrench c1.
2.
Loosen the stopper-protection with a proper wrench c3.
3.
If the actuator angular stroke is stopped before reaching the end position
(fully open or closed), unscrew the stop screw (g) by turning it anticlockwise with
a proper wrench (c2) , until the valve reaches the right position. When unscrewing
the stop screw, keep attention that the protection still with a wrench so that the
sealing washer doesn’t withdraw together with the screw.
4.
If the actuator angular stroke is stopped beyond the end position (fully open or
closed valve), screw the stop screw by turning it clockwise until the valve reaches
the right position.
5.
Tighten the protection for stopper and the plug (t).
Figure 12
16
Section 3: Operation and Use