Flowserve LPC Compact Actuator Series - Manual (Page 14)

4.3 Housing and Scotch Yoke Maintenance
Standard maintenance of the housing may take place in the field.
Standard in–field maintenance
A first standard maintenance is available unscrewing the housing stop bolt (11) and applies a film of grease (with an
applicator) directly on the yoke’s sliding surface.
NOTE: Take note of the length of the stop bolt before making the standard maintenance
and reassemble it at the same length.
Extensive maintenance
If it is necessary to carry out an extra-maintenance inside the housing, perform the following steps:
a WARNING: Ensure that the pneumatic connection ports of the cylinder are disconnected. Also make
sure that all pneumatic supplies to the control unit and all power supplies are disconnected. Finally,
make sure that the actuator is in fail position, i.e. that it is not locked in a
position with the spring compressed by means of locking devices.
4.3.1 Remove the actuator from the valve.
4.3.2 Remove the pneumatic cylinder unscrewing the six screws (29)
and unbolting the piston rod (11) to the guide block (13).
4.3.3 Unscrew the screw locates on the left of the housing stop bolt (33),
remove the flat washer (32) and remove the guide bar (10).
Remove the o-ring (9).
4.3.4 Remove the retaining rings (5), the bushes (4) and the o-rings (31),
unscrew the caps (2) and finally unscrew the two bolts (1). Now, pull
out the output shaft (28) from the housing (30).
4.3.5 Remove the scotch yoke (3) from the housing, unscrew
upper and lower screws (6) and pull out the two washers (7)
and roller bearings (8).
4.3.6 Apply a grease film on the slider surface of the yoke wings (3) and
the roller bearings (8) (For the grease characteristics refer to Grease
Characteristics Table, available upon request to Flowserve After
Sales Department). Replace the o-ring (9).
4.3.7 Reassemble the parts of the housing using a reverse
procedure as previously described.
LPC Compact Actuator Series FCD LFENIM0002-00-AQ 07/14
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