Flowserve Nuclear Qualified Pneumatic Actuator - Manual (Page 2)

Disassembly Procedures
1. Disconnect all air and electrical supplies from
actuator.
2. Remove all accessories from actuator and dismount
from valve.
Spring Group
1. Apply air pressure to the Pneumatic Cylinder to
release spring pressure from the Stop Bolt (16). Remove
both Stop Bolts (16) and release air pressure. This will
relieve the majority of the spring preload.
NOTE: PERSONAL INJURY may result if Step 2 is
attempted before Step 1 is completed.
2. The Spring Cartridge (11) is welded into an integral
component and cannot be disassembled. To remove from
actuator, remove Spring Cartridge Nuts (41) and
Lockwasher (42). At this point, all spring forces are
contained within the welded cartridge and the spring
cartridge can be removed from the center body.
NOTE: Support the Spring Cartridge (11) during removal
so as not to damage the Piston Rod (3).
Rod Cover (Double Acting Actuators)
1. Remove the Rod Cover Bolts (40) and Lockwashers
(42). The Rod Cover (11) can now be removed from the
Housing (1), taking care not to damage the Piston Rod
(3).
Pressure Group
1. Remove the Tie Rod Nuts (28), Tie Rods (27), and the
Endcap (29).
2. Slide the Cylinder (23) over and off of the Piston (24),
being careful not to scratch or dent the honed and chrome
plated surface of the cylinder (23).
3. Remove the Piston Bolt (25), Piston Bolt Lockwasher
(26) and remove the Piston (24) and Piston Face Seal
(32).
4. Remove the Adapter Bolts (43) and carefully slide the
Adapter (22) over the Piston Rod (3).
Housing or Body Group
1. Unscrew the Inspection Cover Screws (9) and
Lockwashers (10) and remove the Cover (8) and the Cover
Gasket (35).
NOTE: Prior to disassembly of remainder of the Body
Group, you should check visually through the inspection
opening to determine whether further disassembly is
necessary. If the Yoke (4), the Yoke Pin (5), and the
Yoke Pin Rollers (6) are in good condition, do not
disassembly further.
2. To remove the Piston Rod (3) and Piston Rod Bearing
(2), center the Yoke in the Mid or 45 degree position.
RN2 Actuators: To remove the Yoke Pin Retainers (7),
use snap ring pliers with 90 degree tips through the
inspection cover opening. Turn the Piston Rod (3) to
remove the Yoke Pin Rollers (6) and the Yoke Pin (5)
through the inspection cover opening.
RN3 and RN4 Actuator: Remove both freeze plugs
that are located in the Housing near the Bearing Retainer
(13). Through these openings the Snap Ring, Yoke Pin
Retainers (7) can be removed. The Yoke Pin Rollers (6)
can now be slipped off of the Yoke Pin (5), and the Yoke
Pin (5) can be pushed through the Piston Rod (3) and out
through the opening in the other side of the housing.
Remove Piston Rod (3) and Piston Rod Bearings (2) at
this time, using care not to scratch the surface of the
Piston Rod.
3. Unscrew the Bearing Retainer Bolts (14) and remove
the Bearing Retainer (13), the Retainer Gasket (37), and
the Torque Shaft Seal (38) from the valve mounting side of
the actuator.
4. The Torque shaft (20) may be tapped out using a soft
faced hammer. Use care not to drop the shaft or the
Bearing (12) when they come out. After removal of the
Torque Shaft (20) repeat step 3 on accessory side.
B00143-0 Page: 2 of 4
11444 Deerfield Road
Cincinnati, Ohio 45242
(513) 489-7800
Maintenance Instructions
Nuclear Qualified Actuator