April 2022
Installation, Operation and Maintenance Manual
E-90090007 Rev. 0
28
Section 8: Operator End Stop Adjustment
Operator End Stop Adjustment
Section 8: Operator End Stop Adjustment
NOTE:
GVO linear operators are shipped with their travel adjusted based on the valve topworks
(if available). Adjustment may require if the pre-installation verification (Section 5.2)
indicates that MOT is larger than MVT.
Each type of operator (SR and FS) will fall into one of two conditions (A or B) if the end stop
is out of adjustment.
NOTE:
Typically, valve with operator should have its travel limited by operator stops (preferably,
MVT is 1/8 in. more than MOT) in order to avoid/prevent any damage to the valve.
Refer to Section 8.1 and Section 8.2 if adjustment is needed.
Refer to Section 4 to confirm the operational style of the fully extended or fully retracted
position of each type of operator (SR and FS).
If the end stop is out of adjustment, the operator will fall into one of two conditions
(with the assumption that valve stem engagement is according to Section 5.2
measurement “B” plus 0.5 to 1 stem pitch):
Condition A:
MOT is more than MVT, which means travel stops on valve instead
of operator.
Condition B:
MOT is less than MVT by more than 1 full pitch of valve stem thread,
which means there is potential leakage due to under travel of valve.
