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C. Do not interchange internal parts or use a different base
after parts have been custom fitted.
Use the following procedure and Figure 27 to determine the
correct limit washer length:
1. Use care to avoid seat damage. Assemble disc holder
ring and disc holder by inserting the holder retainer ring,
beveled side upward, in the groove using the proper inside
snap ring pliers (see Figure
29). Screw the bellows, if
present, onto the disc holder using a new gasket.
2. Tilt the above assembly and slide the limit washer along
the disc holder until it rests on the shoulder of the disc
holder. Be sure the chamfered edge of the limit washer is
down against the shoulder.
3. Install the guide before placing the spindle assembly into
the disc holder assembly.
4. Install the guide gasket. Insert the assembly from Step 3
into the base.
5. Install bonnet gasket and bonnet, leaving out the spring
assembly at this time.
XV. Reassembly
(Contd.)
.680” (17.27 mm)
O.D. max.
Limit Washer
.003” (0.08 mm)
Chamfer
.050” (1.27 mm) x 45˚
Chamfer
Figure 26
Guide
Guide
Bellows
Bellows Gasket
Bellows Ring
Disc Holder
Limit Washer
Limit Washer
Disc Holder
Conventional
Bellows
Required Lift
Limit Washer Length
Measured Lift
C. Limit Washer Length
6. Tighten nuts to compress gasket . Do not use impact
wrench on bellows valves.
7. Place dial lift indicator on bonnet and over spindle, then
zero indicator.
8. By inserting a wood dowel through the nozzle, push the
disc up as far as it will go and measure the lift. Do not lift
the spindle as this will result in a false reading.
9. Subtract the required lift of the valve from the measured
lift to find the required limit washer length.
Note:
The required lift is
- for a D
orifice
.086”
(2.18
mm)
+.005"
(0.13
mm)
- .000" (0.00
mm)
- for an E
orifice
.139”
(3.53
mm)
+.005"
(0.13
mm)
- .000" (0.00
mm)
10. Machine the limit washer to the required length. Chamfer
the inside lower edge, deburr and polish as required.
11. Disassemble the valve, install the limit washer (with
chamfer down), and reassemble valve as before.
Measure the actual lift of the valve and compare it with
the required lift of the valve as noted in Step 9.
12. a) If the actual lift is less than required, machine the lift
washer the additional amount to obtain the required
lift. (Machine chamfer and deburr before installation
into valve.)
b) If the actual lift is greater than the required amount,
obtain new limit washer and begin again with Step 9.
(Machine chamfer and deburr before installation into
valve.)
13. Disassemble valve and continue with next step of
Reassembly on Section XIV.A.
Figure 27: Determining Lift and Limit Washer Length
