Section 7: Troubleshooting; Fault Insertion - Emerson BETTIS G01 Series Disassembly And Reassembly

Service Instructions
127072E Rev. C

Section 7: Troubleshooting

7�1

Fault Insertion

In the unlikely event of a fault developing, the following Fault Location Table is provided to
assist the service engineer to perform troubleshooting. This table is designed to cover as wide
a range of Emerson Bettis actuators as possible. Reference to equipment not supplied should
be ignored.
Table 19�
SYMPTOM
Erratic
movement
Short stroke
Apparent lack
of torque
Troubleshooting
Fault Location Table
POTENTIAL CAUSES
Irregular Supply of Operating
Medium
Inadequate Lubrication
Worn Parts
Defective Valve
Incorrectly Set Stops
(Valve and/or Actuator)
Hardened Grease
Debris Left in the Cylinder or
Housing During Maintenance
Defective Valve
Inadequate Supply Pressure
Incorrect Speed Control Settings Adjust speed controls to increase flow
Exhaust Port Blocked
Pipe Work Blocked, Crushed
or Leaking
Defective Controls
Defective Piston Seal
Defective Rod Seal
Defective Housing Seal
High Valve Torque or Valve
Seized
Defective Spring
Section 7: Troubleshooting
REMEDY
Check operating medium for consistent supply
pressure and correct as necessary
Dismantle, relubricate and reassemble
Dismantle. Visually inspect for significant wear.
Actuator replacement may be required
Consult the valve OEM's documentation
Check the position of the travel stops and readjust
as necessary
Dismantle, remove any hard grease,
relubricate and reassemble
Disassemble cylinder assembly to remove debris.
Reassemble cylinder assemble as necessary
Consult the valve manufacturer's
documentation
Ensure supply pressure is above the minimum
operating pressure of the actuator and that output
torque produced at supply pressure exceeds valve
torque demand
Remove and clean the exhaust port silencers and
replace them
Examine the pipe work for blockages, crushed pipe
or leakage and clear or replace as necessary
Examine the controls and refurbish or renew as
necessary and refer to component manufacturer's
documentation
Dismantle the cylinder assembly and remove
the defective piston seal and fit new seal and
reassemble
Dismantle the cylinder assembly and remove the
defective rod seal and fit new seal and reassemble
Dismantle the housing assembly, remove the
defective seal and fit new seal and reassemble
Consult the valve OEM documentation
Check for noise and/or erratic operation and replace
spring if required
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