Jordan Valve Mark 5108 Series Back Pressure Regulator - Manual (Page 3)

Procedure A: Diaphragm Replacement
1. Isolate the valve from the system by closing
upstream and downstream block valves.
2. Loosen one of the tubing connections on the bonnet.
Allow any residual pressure to bleed off.
3. Remove all tubing connected to the bonnet.
4. Remove the bonnet nuts.
5. Remove the bonnet. If the bonnet sticks in place,
it may be loosened by rapping sharply around its
edge with a rubber-headed mallet. NOTE: 8" and
larger valves are equipped with eye bolts through
which a chain can be fastened to aid in lifting the
bonnet.
6. Remove the spring.
7. Remove the diaphragm plate capscrews and the
diaphragm plate.
8. Remove the old diaphragm.
9. Making sure the dowel pin holes are in the proper
location, place the new diaphragm over the studs
and press down until it is flat against the body and
spool.
10. Replace the diaphragm plate and the diaphragm
plate capscrews.
11. Tighten all diaphragm plate capscrews snugly.
12. Replace the spring.
13. Replace the bonnet and reinstall the bonnet nuts.
14. Tighten the bonnet nuts snugly using a criss-cross
tightening pattern.
15. Reinstall the control tubing.
16. Reopen the upstream and downstream block valves.
17. Before placing the valve back in service, perform
the air bleed procedure described in the first section
of the manual.
Procedure B: Correction of Binding Stem
1. Perform Steps 1 thru 6 of Procedure A, above.
2. Remove the spool assembly from the valve. NOTE:
On smaller valves, this can be accomplished simply
by grasping the stem and pulling upward. Valves
6" and larger have the top of the stem threaded to
accept an eyebolt to aid in lifting the spool out of the
body. 6" thru 12" valves are threaded 3/8-16. 14" and
16" valves are threaded 5/8-11.
3. Carefully examine both ends of the stem for deep
scratches, scoring or buildup of mineral deposits.
Polish the stem if necessary using a fine grade of
emery cloth.
4. Similarly, examine and polish the upper bushing (in
the bonnet) and the lower guide (in the seat ring).
5. Reinstall the spool assembly.
6. Reassemble the valve, following Steps 12 thru 17 in
Procedure A.
Procedure C: Seat Disc Replacement
1. Perform Steps 1 and 2 of Procedure B, above.
2. With the spool assembly removed from the body,
remove the seat retainer screws.
3. Slide the seat retainer off the lower end of the stem.
4. Remove the seat disc from its groove in the spool.
NOTE: The seat disc may fit quite tightly in the
groove. If necessary, it may be pried out using a
thin-bladed screwdriver or similar tool.
5. Install the new seat disc in the groove.
6. Reinstall the seat retainer and tighten the seat
retainer screws.
7. Reassemble the valve, following Steps 5 and 6 of
Procedure B.
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