Installation, Operation and Maintenance Manual
XXXXXXXX Rev. 1
July 2016
8
Section 5: AT Series Gearbox Operation
AT Series Gearbox Operation
Figure 5
Another View of Hand Wheel Rotation
5.2
Stopper Setting
1.
There are two mechanical stoppers on all AT Series gearboxes to limit the stroke
from ‘open’ to ‘close’.
2.
This stroke of 90° needs to be set correctly for all gearboxes as described below.
3.
Withdraw the stoppers completely. Rotate the valve to the fully closed position
by rotating the hand wheel clockwise. Once the valve is fully closed, advance the
stopper till it touches the sector gear. Secure this stopper position with a nut.
4.
Similarly, for stopper setting at fully open position of the valve, withdraw the
stopper at open side completely. Rotate the valve to the fully open position by
rotating the hand wheel anti-clockwise. Once the valve is fully opened, advance
the stopper till it touches the sector gear. Secure this stopper position with a nut.
