December 2020
Installation, Operation and Maintenance Manual
MAN 606 Rev. 5
Operation and Use
19
Section 3: Operation and Use
3.3.3
Emergency Manual Operation by MSJ - MHW
The MSJ jackscrew manual override can be supplied for OLGA actuators
from model 0.3
to model 3
. The override is mounted on the left side of the actuator, the jackscrew end
is screwed into the guide block. A bronze split screw nut is mounted inside the body.
By rotating the engagement lever, the screw nut is engaged with the jackscrew. When the
screw nut is engaged with the jackscrew manual operation follows by rotating the body of
the screw container by a lever. The manual jackscrew, on request, could be furnished with
fixed handwheel welded on it.
Figure 16
3.4
Calibration of the Angular Stroke
The angular stroke of the yoke can be adjusted between 82°÷98° (±4° with respect to
the nominal positions of complete opening and closing) by means the mechanical stops
screwed into the left side of the housing (open valve) and into the end flange of the
hydraulic cylinder (closing) (Figure 17).
Figure 17
Mechanical Stops
