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4195KA, KB, and KC Series
ther bearing. Tighten the drive flexure screws to hold
pivot assembly A in this position. Do not bend or twist
the flexure when tightening the screws.
12. Decrease the remote set point pressure to 0 psig.
13. Connect the end of link A (key 116) to the pivot
lever arm in the same holes noted in step 3.
14. Replace the tie bar (key 106).
15. Perform the remote set point maintenance calibra-
tion procedure. Perform the appropriate process indi-
cator zero and span calibration and flapper alignment
procedures in section 3 or 4.
Replacing Pivot Assembly B (Key 115)
1. Decrease the remote set point pressure to 0 psig.
2. Note the holes where links A and B are connected.
Disconnect links A and B (keys 116 and 126) from the
arms of pivot assembly B (key 115).
3. Remove the two screws (key 102) that attach pivot
assembly B to the mounting plate (key 111). Remove
the pivot assembly.
4. Loosen the linearity adjustment screw on the re-
placement pivot assembly and set it in the same posi-
tion as the adjustment on the original pivot assembly.
Tighten the screw.
5. Set the replacement pivot assembly on the mount-
ing plate, and attach it with the two machine screws.
6. Attach links A and B (keys 116 and 126) to the
arms of the replacement pivot assembly in the same
holes noted in step 2.
7. Perform the remote set point maintenance calibra-
tion procedure. Perform the appropriate process indi-
cator zero and span calibration and flapper alignment
procedures in section 3 or 4.
Replacing the Drive Flexure
1. Using an Allen wrench, remove the cap screws
(key 12) and washers (key 13) to disconnect the drive
flexure (key 79) from the drive bracket (key 121) and
from the adjustment arm of pivot assembly A. Remove
the drive flexure.
2. Set the remote set point pressure to 50 percent of
the remote set point input range.
See figure 5–20. The adjustment arm of
the remote set point pivot assembly A
turns on a bushing at each end of the
shaft supporting the adjustment arm. In
the next step, position the shaft so both
bushings ''float'' inside the bearings
5–32
Note
and do not rest against the end of either
bearing.
3. Connect the new drive flexure making sure it stays
straight and vertical. Adjust the length of the pivot arm,
if necessary, until the drive flexure is straight. Before
tightening the drive flexure screws, hold the pivot as-
sembly A shaft in the middle of the bushing end play.
Be sure neither bushing is resting against the inside
end of either bearing. Tighten the drive flexure screws
to hold the pivot shaft in this position. Do not bend or
twist the flexure when tightening the screws.
4. Decrease the remote set point pressure to 0 psig.
5. Perform the remote set point maintenance calibra-
tion procedure. Perform the appropriate process indi-
cator zero and span calibration and flapper alignment
procedure in section 3 or 4.
Replacing the Remote Set Point Tubing
1. Decrease the remote set point pressure to 0 psig.
2. Using two 5/16-inch open-end wrenches, discon-
nect the pressure connection union (key 93) from the
pedestal assembly (key 105) and the connection to the
case exterior at the top of the case.
3. Remove the tubing (key 104).
4. Install the replacement tubing, and reconnect the
two pressure connections.
5. Apply full remote set point pressure, and check for
leaks.
Replacing Link A
This procedure describes link A (key 116) replacement
in the remote set point assembly. Figure 5–23 shows
the link location.
1. Note the holes where link A is connected. Discon-
nect link A (key 116) from the lever arms on pivot as-
sembly A and pivot assembly B.
2. Loosen the screw in the replacement link A and
adjust the length to match the link being replaced.
Tighten the screw.
3. Refer to figure 5–23 for the correct link orientation.
Attach the replacement link A to the two lever arms in
the same holes noted in step 1.
4. Perform the remote set point maintenance calibra-
tion procedure. Perform the appropriate process indi-
cator zero and span calibration and flapper alignment
procedures in section 3 or 4.
Replacing Link B
This procedure describes link B (key 126) replacement
in the remote set point assembly. Figure 5–23 shows
the link location.
1. Note the holes where link B is connected. Discon-
nect link B (key 126) from the pivot arm and from the
set point indicator.
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