Flowserve Logix MD+ ValveSight - Manual (Page 64)

ValveSight™ Diagnostics DTM Manual for Logix MD+ Positioner with HART®
FCD- LGENSF0014-00
© Flowserve Corporation
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mechanical obstruction, loosen the packing, clean the stem, repair or
replace the actuator, repair the valve if galling is suspected.
Closed Too Far
•
Definition: The valve has closed farther than it did at the last calibration
•
Implications: While the valve was in use, it closed farther than it did at
the last calibration by 0.5%.
•
Possible Solutions: Check the feedback arm linkage and ensure the
valve stem connection is tight. Recalibrate the stroke. If the process
cannot be interrupted a service technician may be able to adjust the
calibration.
Opened Too Far
•
Definition: The valve has opened farther than it did at the last
calibration
•
Implications: While the valve was in use, it opened farther than it did at
the last calibration by 0.5%.
•
Possible Solutions: Check the feedback arm linkage and ensure the
valve stem connection is tight. Recalibrate the stroke. If the process
cannot be interrupted a service technician may be able to adjust the
calibration.