Bourdon Tube Controller Maintenance And Calibration; Replacing The Bourdon Tube; Replacing Bourdon Tube Controller Links - Emerson Fisher KC Series Instruction Manual

4195KA, KB, KC, and KS Controllers
W5747 IL
Figure 6-14. Disconnecting Link 1 from the Bourdon Tube
Bourdon Tube Controller Maintenance
and Calibration

Replacing the Bourdon Tube

WARNING
Refer to the Maintenance WARNING
on page 6-1.
Refer to figure 7-2 for key number locations. Refer
to figure 6-13 for a detailed photograph of the
Bourdon tube controller link locations and
adjustments.
1. Disconnect link 1 (key 382) from the Bourdon
tube (key 383) as shown in figure 6-14.
2. Unscrew the tubing nut from the Bourdon tube to
allow for Bourdon tube removal.
3. Remove the self-tapping screws (key 384) that
fasten the Bourdon tube (key 383) to the indicator
assembly (key 101).
4. With care, separate the Bourdon tube (key 383)
from the process tubing assembly (key 381) and lift
out the Bourdon tube.
5. Carefully place the replacement Bourdon tube in
position and start the two self-tapping screws.
Connect the process tubing assembly then tighten
the self-tapping screws to secure the Bourdon tube.
6. Apply process pressure equal to the process
scale upper limit and check for leaks. Remove
process pressure.
6-20
7. Connect link 1 to the Bourdon tube.
8. With the process pressure at 0 percent, the
process pointer should indicate 0 percent on the
process scale. If not, loosen the two screws on link 1
and adjust the length of link 1 to position the process
pointer at 0 percent. Tighten the screws.
9. Perform the controller calibration procedures and,
if necessary, the appropriate remote set point
calibration procedure in Section 3, 4, or 5.
Replacing Bourdon Tube Controller
Links
WARNING
Refer to the Maintenance WARNING
on page 6-1.
This section describes the separate replacement of
four links in the controller. Figure 6-13 shows the
location of each link. To clarify the location of each
link, the links are numbered as follows:
D Link 1 connects the Bourdon tube and the
process pointer
D Link 2 connects the process pointer and the
flapper assembly (key 11)
D Link 3 connects the set point indicator and the
set point beam assembly (key 23)
D Link 4 (key 65) connects the flapper assembly
and the bellows bracket (key 31).
Replacing Bourdon Tube Controller Link 1
1. Remove the two screws (key 6), and lift off the
proportional band indicator cover (key 36).
2. Note the hole position of link 1 in the process
pointer. As shown in figure 6-14, disconnect the link
from the Bourdon tube and from the process pointer.
Adjust the length of the replacement link to the same
length as the link being replaced.
3. Attach the replacement link to the original holes
in the process pointer and the Bourdon tube. If you
do not know in which hole in the process pointer the
link was connected, place it in the middle hole. If
during the process indicator zero and span
calibration, the pointer will not travel the full scale
Instruction Manual
Form 5207
April 2007