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Instruction Manual
D103565X012
Figure 11. Actuator/Bonnet Bolting Sequence
Determination of Ball Closed and Open Position
The purpose of the following procedure is to establish the 'closed' and 'open' position for the ball/shaft assembly.
Refer to figure 12.
When the valve assembly is put together, the exact position of the ball relative to the seal is not known. A procedure
was developed to locate the closed or 0° position from a nonspecific open starting point which is considered a final ball
position to achieve expected shut-off; however, at this final position, the exact centerline of the ball may or may not be
aligned with the exact centerline of the seal ring/pipeline. The ball is slowly rotated from a general open position into
the seal until a slow, low pressure stream of water flowing through the valve is reduced to near-zero flow
(coarse-adjustment).
The closed, travel stop is then set. This is a starting position considered a point where the ball has rotated far enough
into the seal to close off the flow passage, however, may still allow considerable seat leakage as compared to Class V
shut-off performance. The closed travel stop is then incrementally adjusted to increase torque of the ball into the seal
until Class V shutoff performance is attained (fine-adjustment).
The closed position is then considered final at this point. Once the closed position is established and seat leakage is
acceptable, the ball is then rotated counter-clockwise (CCW) 90° to establish the open position, and the open travel
stop is engaged. The valve assembly ball adjustment is then considered complete.
CAUTION
Dry cycling this valve into the metal seat may damage the ball and seal. Make sure process fluid is in the valve. If the system
pressure can be relieved, then this is preferred.
SS-264 Valve
September 2021
19
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