Type Y693
6
To Disassemble and Reassemble Diaphragm
Parts:
For the Aluminum lower casing version only:
Key numbers are referenced in figures 3 & 4.
1. Remove the downstream external control line.
Remove the closing cap (key 3), and turn the adjusting
screw (key 2) counterclockwise to remove the adjusting
screw (key 2). Remove the upper spring seat (key 4 or
44) and the control spring (key 1).
2. Remove the hex nuts (key 22), cap screws (key
21), and spring case (key 23).
3. Remove the diaphragm assembly (key 5) plus
attached parts by tilting them so that the pusher post
(key 8) slips off the lever assembly (key 49). To sepa-
rate the diaphragm (key 5) from the attached parts,
unscrew the spring holder cap screw (key 30) from the
pusher post (key 8).
4. Inspect the pusher post and replace if required.
5. To replace the lever assembly (key 49), remove the
machine screws (key 11), cotter pin (key 14), and clevis
pin (key 10). To replace the valve stem (key 13), unscrew
the cap screws (key 18) from the body (key 28) and
remove the lower casing assembly (key 9). Pull the valve
stem (key 13) out of the lower casing assembly (key 9).
6. To inspect the body bushing (key 97), remove the
bushing snap ring (key 74) and carefully remove the
body bushing from the lower casing assembly (key 9).
7. During the assembly procedure, use lubricants on
parts as indicated in figure 4 and replace parts as
required.
8. Install the body bushing O-ring (key 64) on the
body bushing (key 97). A wiper retaining ring (key 63) is
required to hold the wiper (key 66) in place while the
bushing is installed into the lower casing assembly (key
9). Ensure that the wiper is properly oriented with the
wiper lip pointing inward toward the diaphragm. Install
the bushing snap ring (key 74) to hold the body bushing
in place.
9. Apply a moderate coating of lubricant to the valve
stem (key 13). Install the stem O-ring (key 15) and the
two back-up rings (key 69, one on each side of the
O-ring) onto the valve stem (key 13).
10. Install the valve stem (key 13) from the body side
of the bushing, this is to ensure that the O-ring groove
does not damage the wiper.
11. Install the lever assembly (key 49) into the stem
(key 13) and insert the clevis pin (key 10) and cotter pin
(key 14). Secure the lever assembly (key 49) with the
machine screws (key 11). Carefully tighten the machine
screws to a torque of 7 to 9 foot-pounds (9 to 12 N•m).
12. Install the diaphragm and plate assembly (key 5,
pattern side up) on the pusher post. Then install the
lower spring seat (key 4).
13. Lubricate the diaphragm cap screw threads (key
30) and insert the cap screw to secure the diaphragm
parts to the pusher post (key 8). Carefully tighten to a
torque of 7 to 9 foot-pounds (9 to 12 N•m).
14. Install the assembled parts in the lower casing
(key 9). Make sure that the lever (key 49) fits in the
pusher post (key 8) and that the holes in the diaphragm
align with the holes in the lower casing.
15. Install the spring case (key 23) on the lower
casing assembly (key 9) so that the vent assembly
(key 56) is correctly oriented, and secure with the cap
screws (key 21) and hex nuts (key 22) fingertight only.
16. Insert the control spring (key 1) into the spring
case (key 23), followed by the upper spring seat (key 4
or 44) and the adjusting screw (key 2).
17. Turn the adjusting screw (key 2) clockwise until
there is enough control spring (key 1) force to provide
proper slack to the diaphragm (key 5). Using a crisscross
pattern, finish tightening the cap screws (key 21) and
hex nuts (key 22) to 18 to 21 foot-pounds (24 to 28 N•m)
of torque. To adjust the outlet pressure to the desired
setting, refer to the Startup and Adjustment section.
18. Install a replacement closing cap gasket (key 35)
if necessary, and then install the closing cap (key 3, if
required).
19. Connect the downstream control line and refer to
the Startup section before putting the regulator back in
operation.
For the Steel or Stainless Steel lower casing
version only:
Key numbers are referenced in figures 3 & 5.
1. Remove the downstream external control line.
Remove the closing cap (key 3, if required), and turn
the adjusting screw (key 2) counterclockwise to remove
the adjusting screw (key 2). Remove the upper spring
seat (key 4 or 44) and the control spring (key 1).
2. Remove the hex nuts (key 22), cap screws (key 21),
and spring case (key 23).
3. Remove the diaphragm assembly (key 5) plus
attached parts by tilting them so that the pusher post
(key 8) slips off the lever assembly (key 9). To separate
