Trim Replacement - Fisher Design CAV4 Instruction Manual

A7089 / IL
Figure 8. Typical Balanced TSO Trim
CAUTION
Hold the power torque wrench and at-
tached socket wrench extension at right
angles to the cage retainer when apply-
ing torque. Tilting the wrench and exten-
sion while applying torque causes the
lugs on the cage retainer tool to sudden-
ly disengage from the recesses in the
retainer, damaging the retainer and the
lower cage assembly (key 2).
e. Remove the cage retainer (key 5).
f. Remove the seat ring (key 35) and O-ring (key
36), if used.
6. The 4 and 6-inch lower cage assemblies (key 2)
have tapped holes to aid in removal. Refer to table 7
for hole diameter and thread type. Install eyebolts or
similar devices into these holes. Carefully lift the lower
cage assembly (key 2) straight out of the valve body.
7. Remove the cage gasket (key 7).
Table 7. Hole Diameter and Thread Type for Cage Removal
Valve Size,
Inch
2
3
4
6
The seat ring (key 35) or integral seat
VALVE PLUG
cage assembly (key 2) has a soft metal
SEAL
seat. To avoid damage to the seating
surfaces, DO NOT lap this surface. If this
area needs repair, contact your Fisher
Controls sales representative or sales
office for assistance.

Trim Replacement

PROTECTED
The 3-inch CAV4 valve is a clamped-in
SOFT SEAT
trim design. No cage retainer is used.
See figure 10. Therefore, if you are using
these instructions for a 3-inch valve, dis-
regard references to a cage retainer.
After all trim maintenance has been completed, re-
assemble the trim by following the steps below.
Be certain that all gasketed surfaces are clean. Use
new gaskets (keys 6 and 7) during assembly.
1. If the lower cage assembly (key 2) and cage retain-
er (key 5) remained in the valve body (key 1), proceed
to step 4.
If these parts were removed, read the following caution
and proceed to step 2:
To avoid galling or improper gasket
loading that may result in leakage, thor-
oughly clean the threads and the gasket
surfaces in the valve body (key 1), the
valve body bore, and the cage retainer
(key 5). Lubricate the surfaces indicated
in figure 9 with the appropriate lubricant.
Be certain to lubricate all of the follow-
ing mating surfaces:
threads,
of the flange on the lower cage assem-
bly.
Design CAV4
Upper Cage
2 holes, 1/4-20 UNC
2 holes, 3/8-16 UNC
2 holes, 3/8-16 UNC
2 holes, 1/2-13 UNC
CAUTION
Note
CAUTION
D cage retainer and valve body
D bottom of the cage retainer and top
Lower Cage
Assembly
- - -
4 holes, 1/4-20 UNC
4 holes, 1/4-20 UNC
4 holes, 3/8-16 UNC
11