Flowserve 51 Series Fire-Safe Valves - Manual (Page 8)

8 19406-H
For Rev. R1 models, remove shaft clip (15F) (not reusable part!) (see
note above) and the S.S. washer from the shaft. Then remove the top
pinion bearing (15G) and the bottom pinion bearing (15H) by
carefully prying them away from the body.
CAUTION: Both of these bearings may have a projecting “nib”
which locates the bearings to the actuator body. Be careful not
to break off these nibs inside the body when removing the top
and bottom bearings. NOTE: Top bearing is marked “Top”.
Bottom bearing has a larger ID than the top bearing.
Next, slide the shaft out through the bottom of the body and remove
the top O-ring (15D) and the bottom O-ring (15E) from the body.
h. All rebuilding kit O-rings and bearings may now be
installed if all the actuator surfaces are clean and free of
grit and scratches. If the inside walls of the body are
scored, or the guide rod surfaces are scratched, the
actuator will leak after rebuilding. New “unscored” parts
should be obtained from the factory. Light tracking, barely
detectable to touch, is acceptable.
i. Lubricate the actuator thoroughly with a #1 grease. Apply
a light film of grease to all O-rings.
2. ACTUATOR REASSEMBLY
a. Some Rev. R2 actuators, sizes 10-35, use different
bearings in the end caps. They resemble a “top hat”, and
are installed with the brim of the hat facing out.
These bearings are retained by “star washers” (16). These
bearings and star washers should not be removed for O-
ring seal replacement. On sizes 10 & 15 only, there is one
star washer, or retainer, per bearing. On sizes 20-35,
there are two star
washers per
bearing. They are
installed one on top
of the other, with
the “points” of the
“star” overlapping
each other (as
opposed to being
on top of each
other). All the washers must be pressed in firmly and
straight. The points of star are bent slightly. When
installed, they bear back, away from the hole.
For sizes 10-35 Rev. R1 thru R6 actuators, replace the
two split-ring style bearings (6A) and one guide rod O-
ring (15B) in each end cap.
Replace the split-ring style bearing (6B) and guide rod O-
ring(s) (15B) into I.D. groove(s) in each piston. Install O-
Rings (15C) onto pistons.
Replace O-ring (15E) and bearing (15H) on the bottom of
shaft. On the top of the shaft add the two S.S. washers
with the thrust bearing (10) between them. Locate the top
bearing (15G) and O-ring (15D) into the body.
NOTE: For Rev. R6 actuators, the top bearing (15G) is flat, the same
as and interchangeable with thrustbearing (10). Replace the shaft thru
the larger opening in the bottom of the body.
For Rev R3 thru R6, sizes 25 through 35 actuators,
replace anti-ejection right (15J) in its groove on the shaft
(2B), if removed.
For Rev. 1 models:
Locate the shaft O-rings into the actuator body. O-ring
(15D) is the top O-ring while (15E) is the bottom O-ring.
Replace the top bearing (15G) and bottom bearing (15H).
Replace the shaft in the body through the bottom of the
actuator body.
Replace the anti-ejection ring (15J) in its groove on the
shaft (2B), if removed. Check that the ring is properly
seated in its groove.
b. Very carefully align the piston guide rod assemblies inside
the body. Keep the pistons square to the body. (This is
very important in the 30 39 actuator where steel set
screws can cause internal body damage if the piston
assemblies “cock” inside the actuator body.)
IMPORTANT: One piston guide rod assembly has a thru hole drilled in
it. It can be easily located by looking down the ends of both guide
rods. This piston assembly must be reassembled, with its respective
guide rod opposite the nameplate on the body, as it was removed.
c. Align the shaft so that the teeth on the shaft will “pick up”
the piston assembly’s rack teeth when turning the top
extension of the shaft clockwise (CW). (See Figure 1.)
IMPORTANT: Proper 90° rotation can only be ensured if the shaft
teeth begin to mesh with the piston assembly’s teeth at the “proper
tooth” between these meshing gear pairs. (See Figure 1.)
d. To ensure proper meshing of teeth, move the shaft 15-20
degrees counter-clockwise (CCW) from its normal
position when the piston assemblies are located at the
body ends. (See Figure 2).
NOTE: The “normal position” of the shaft on the 10-20 sizes is when
the top flats are parallel to the main axis of the actuator body. On the
25-35 sizes the teeth of the shaft will be on the left side of the
actuator when viewed from the ends of actuator (see Figure 1).
e. With the piston assemblies in the body, gently push each
piston into the body. Turn the top shaft extension
clockwise (CW). Do not allow the pistons to “cock”.
At the proper point of engagement between the shaft and
piston assemblies, both piston assemblies will move
toward the center of the body when turning the top shaft
extension of the actuator clockwise (CW).
f. Once the center gear and pistons are properly engaged,
ensure that smooth movement and 90˚ operation can
Flow Control Division
Worcester Controls