Flowserve Valtek VL-C Spring Cylinder Linear Actuators - Manual (Page 2)

54-2 Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611
Installation
Prior to installation, make sure adequate overhead
clearance for the actuator is provided to allow for proper
removal from the valve body and for proper mainte-
nance. Refer to Table I.
5. Make sure positioner mounting bolts, linkage and
stem clamp are fastened securely.
6. Ensure all accessories, brackets and associated
bolting are fastened securely.
7. Check rubber bellows for wear.
8. Spray soap solution around the base and top of the
cylinder, the adjusting screw and the lower actuator
stem bushing to check for air leaks through the
O-rings and gasket.
9. Clean any dirt or foreign material from the actuator
stem.
10. If an air filter is supplied, isolate the air filter, then
check and replace cartridge as necessary.
DISASSEMBLY AND REASSEMBLY
Disassembling the Actuator
Refer to Figures 1 through 4 to disassemble the cylinder
actuator.
1. Shut off air supply. If actuator is installed on a
Flowserve valve, remove the valve per the appropri-
ate installation operation, maintenance instructions.
WARNING: To avoid serious injury, depressur-
ize the line to atmospheric pressure and drain
all fluids before working on the actuator.
2. Disconnect all tubing. Remove stem clamp and
stem bellows from the actuator stem.
3. Relieve spring compression by completely remov-
ing the adjusting screw. Remove adjusting screw
gasket from adjusting screw.
WARNING: To avoid serious personal injury,
relieve the spring compression before further
disassembly. The cylinder end cap may fly off
the yoke when removing the cylinder tie-rod
nuts.
4. Remove the four self-locking tie rod nuts by un-
screwing in an alternating pattern. Remove the
cylinder end cap.
5. Lift the cylinder off the yoke and piston. If excessive
O-ring resistance is felt, use a rubber mallet to
gently tap around the cylinder perimeter.
WARNING: To avoid serious personal injury, do
not use air pressure to remove the cylinder. The
cylinder may fly off the yoke.
CAUTION: When removing the actuator stem
lock nut, do not hold the actuator stem with a
pipe wrench as the sealing surface may be
damaged; instead, use a wrench on the flats of
the actuator stem.
6. For air-to-retract configurations, remove the
spring(s) and spring button for cleaning and inspec-
tion (see Figures 1, 3 and 4). Remove the actuator
Table I:
Overhead Clearance for Maintenance
Actuator Size Minimum Clearance
100, 150, 200 9 inches
NOTE: If an actuator is attached to a valve body
assembly, see the appropriate installation, operation,
maintenance instructions.
1. Connect the air supply and instrument signal air
lines to the two marked connections on the
positioner. Since both the cylinder and positioner
are suitable for 150 psi (10.3 bar) air supply, an air
regulator should not be used unless the supply
exceeds 150 psi (10.3 bar).
NOTE: In some cases, air supply must be limited to
100 psi (6.9 bar) rather than 150 psi (10.3 bar); this
will be indicated by a sticker found near the upper
air port on the cylinder.
WARNING: To avoid personal injury or equip-
ment damage, do not exceed recommended
supply pressure.
2. Installation of an air filter on the supply line is
recommended.
3. Use a soap solution to make sure all air connections
are leak-free.
MAINTENANCE
At least once every six months, check for proper opera-
tion by following the preventative maintenance steps
outlined below.
These steps should not be performed
while the actuator is in service. If an internal problem is
suspected with the actuator, refer to the
Disassembly
and Reassembly section.
WARNING: To avoid serious injury, the following
steps should only be performed with the air supply
or positioner input disconnected.
1. When disconnecting air supply, observe actuator
for correct fail-safe action.
2. Examine the actuator for damage caused by corro-
sive fumes and process drippings.
3. Clean the actuator and repaint any areas of severe
oxidation.
4. If possible, stroke the actuator and check for
smooth, full-stroke operation.
WARNING: To avoid serious injury, keep hands,
hair and clothing away from all moving parts
while operating the actuator.