Flowserve Logix MD+ ValveSight - Manual (Page 63)

ValveSight™ Diagnostics DTM Manual for Logix MD+ Positioner with HART®
FCD- LGENSF0014-00
© Flowserve Corporation
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checking linkages for wear, misalignment, and tightness. After
maintenance, reset the cycle accumulator.
Valve Travel
•
Definition: The total accumulated valve travel limit has been
exceeded.
•
Implications: The travel is accumulated in both directions. The travel
counting criterion and limit are set by the user to track the usage of the
valve.
•
Possible Solutions: Follow routine procedures for maintenance when
the limit is reached such as checking the packing tightness, and
checking linkages for wear, misalignment, and tightness. After
maintenance, reset the travel accumulator.
Bellows Cycles
•
Definition: The bellows cycle limit has been exceeded.
•
Implications: The bellows may be reaching the end of its fatigue
life. Each cycle represents two reversals of the direction of bellows
movement. The cycle counting criterion and count limit are set by the
user to track the usage of the valve.
•
Possible Solutions: Follow routine procedures for maintenance when
the limit is reached such as checking bellows for cracking or
leaking. After maintenance, reset the cycle accumulator.
Bellows Travel
•
Definition: The bellows cycle limit has been exceeded.
•
Implications: The bellows may be reaching the end of its fatigue
life. Each cycle represents two reversals of the direction of valve
movement. The cycle counting criterion and count limit are set by the
user to track the usage of the valve.
•
Possible Solutions: Follow routine procedures for maintenance when
the limit is reached such as checking bellows for cracking or
leaking. After maintenance, reset the cycle accumulator.
Valve Can't Open
•
Definition: Pressure has been applied (or removed) to open the valve,
but the valve is not opening.
•
Implications: This may be caused by excessive friction.
•
Possible Solutions: Verify adequate supply pressure is applied. Verify
the feedback linkage is connected. View the friction trends if
available. Consider the following: Clear any external or internal
mechanical obstruction, loosen the packing, clean the stem, repair or
replace the actuator, repair the valve if galling is suspected.
Valve Can't Shut
•
Definition: Pressure has been removed (or applied) to close the valve,
but the valve is not closing.
•
Implications: This may be caused by excessive friction.
•
Possible Solutions: Verify adequate supply pressure is applied. Verify
the feedback linkage is connected. View the friction trends if
available. Consider the following: Clear any external or internal