Jordan Valve Mark 66 Series – Air Loaded Pressure Regulator - Manual (Page 3)

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Place a piece of 4/0 polishing cloth or jewelers cloth
on a smooth, flat surface, and polish the lapped
seating surfaces of the disc, plate and disc guide
using a figure “8” motion. If the parts are scarred,
do not attempt to relap them, but return them to the
factory for repair or replacement. Often parts can
be repaired at a minimal cost if the parts are not
scarred too deeply.
6. The vertical sections of the disc guide serve as
guides for the disc while stroking. A 0.005 feeler
gauge should be used to check for clearance be-
tween this surface and the side of the disc. If the
clearance is less, clean the guide surfaces in the
disc guide with a fine file.
B. Reassembly
* Sizes 1/2” to 1-1/2”
1. Place the plate in the body, lapped surface facing
the cap. The index pin hole should be on the same
side as the “<” on the body. Align the disc pin so
that it is centered in the body bore and protrudes
through the center slot in the plate.
2. Place the disc on the plate, engaging the disc pin.
The arrow on the disc should point to the index-pin
hole. Insert the index-pin in the hole.
3. Place the disc guide onto the plate, engaging the
index pin. Rotate the assembly slightly until slot
openings in the disc are parallel to the openings in
the plate, and perpendicular to the stem. Stroking
the valve will aid in this alignment.
4. Align the “>” on the cap with “<” on the body, and
place the cap over the two studs in the body.
5. Install the nuts and cap bolts. Hand tighten. Proceed
to STROKE ADJUSTMENT to check the orifices align-
ment of the seats, when properly aligned torque the
body bolts as outline under TORQUE PROCEDURE.
* 2” size
1. Place the plate in the body and replace the guide
screws. Tighten the screws but do not allow them to
bind the disc against the plate.
2. Replace disc and plate assembly in the body so the
disc pin engages the disc, and the plate is seated
firmly in the body.
3. Rotate the assembly slightly so that the slot openings
in the disc are parallel to the openings in the plate
and perpendicular to the stem. Stroking the valve will
aide in this alignment.
4. Replace the pressure ring and cap. Install the nuts
and cap bolts, hand tighten.
5. Proceed to STROKE ADJUSTMENT to check the ori-
fices alignment of the seats. When properly aligned
torque the body bolts as outlined under TORQUE
PROCEDURE.
* 2-1/2” through 6” sizes
1. Install the new “plate-body” gasket. Place the plate
in the body so the disc pin protrudes through the
center slot in the plate. The marking “TOP REVERSE”
must be towards the diaphragm.
2. Place the disc on the guide pins in the plate, engag-
ing the disc pin arm protruding through the center of
the plate. The arrow on the disc must point towards
the diaphragm.
3. Install the “cap-body” gasket. Be sure the disc spring
is installed in the center web of the cap and install
the cap with the center web parallel to the stem.
Install the cap to the body using only two body bolts
180° apart.
4. Apply 20 psi minimum air pressure to the 3/8 NPT
hole in the side of the upper diaphragm case and
check the orifice alignment of the disc and plate. The
orifices should be fully open and in perfect align-
ment. If they’re not, proceed to STROKE ADJUST-
MENT before torquing the body bolts per TORQUE
PROCEDURE.
Diaphragm Replacement
Disassembly
1. In removing the diaphragm, first remove the disc and
plate as previously covered under VALVE SEATS.
2. Remove the upper diaphragm case.
3. Holding the disc pin with an open end wrench,
loosen the locknut and remove the diaphragm as-
sembly by rotating counterclockwise. The diaphragm
assembly consists of the upper diaphragm plate,
diaphragm, and lower diaphragm plate.
4. If the diaphragm must be replaced:
*1/4” - 2” sizes: Secure the upper diaphragm plate
in the vise. A face spanner wrench should be used to
remove the lower diaphragm plate from the assembly. If
a face spanner wrench is not available, use a punch and
hammer, but make certain to remove all burrs prior to
reassembling.
*2-1/2” - 6” sizes: Secure the lower diaphragm plate in
the vise. Use a wrench on the hex of the upper dia-
phragm plate and turn counterclockwise to remove.
5. Remove the diaphragm and replace with new one
in reverse order. Tighten. For elastomer diaphragms,
clean (degrease) threads and apply one drop of
Loctite #290. Thread the parts together and tighten
1/8 to 1/4 turn.
Stem & Disc Pin Replacement
1. Remove the disc and plate, following the procedures
outlined under VALVE SEATS.
2. Remove the diaphragm as outlined under DIA-
PHRAGM REPLACEMENT.
3. Holding the disc pin assembly with an open end
wrench, loosen the stem locknut. The stem can now
be unscrewed from the disc pin and the locknut
removed from the stem.
4. Remove the stem upward through the diaphragm
area and the disc pin through the body orifice.