MR95 Series
16
Table 7.
Torque Specifications
BoDy SizE
SPRiNG caSE BoLTS
(1)
ORIFICE
PLuG GuiDE
Inches
DN
F
oot-
pounds
N•m
F
oot-
pounds
N•m
F
oot-
pounds
N•m
1/4
1/2
3/4 and 1
1-1/2 and 2
- - - -
15
20 and 25
40 and 50
6 to 8
10 to 13
24 to 30
40 to 50
8.1 to 11
13 to 18
33 to 41
54 to 68
6 to 8
34 to 39
45 to 50
180 to 200
8.1 to 10.8
46 to 53
61 to 68
244 to 271
50 to 58
75 to 90
100 to 125
170 to 200
68 to 79
102 to 122
136 to 169
230 to 271
1. Reduce spring case bolt’s torque by 30% when using Ethylenepropylene (EPDM) diaphragms.
10. If the unit has metal diaphragms (see Figures 4
and 5):
a. (Applicable only for the lower diaphragm head
of Types MR95H, MR95HT, and MR95HD,
1-1/2 and 2-inch / DN 40 and 50.) Find the
pusher post (key 10) and place on a surface
with the larger flat surface down and the thread
stem up (metal diaphragm pusher post has
a recessed diameter in the bottom surface).
Then, find one smaller composition gasket
(key 29) and fit it over the threaded end of
the pusher post. Find and take one of the
diaphragm heads and slip it over the threaded
end of the pusher post with the chamfered
side of the diaphragm head toward the gasket.
Take a second gasket and place it over the
threaded end of the pusher post on top of the
diaphragm head.
b. Replace one of the two large diaphragm
gaskets (key 19) on the surface of the body
(key 1) that will support the diaphragms
(key 12). There will be two diaphragms used
per regulator, except for Types MR95L and
MR95LD, 1/4 NPT with 2 to 6 psi / 0.14 to
0.41 bar spring range setting which use only
one metal diaphragm (the metal diaphragm is
in between two diaphragm gaskets). Another
diaphragm gasket will be placed on top of the
second metal diaphragm. The raised surfaces
of the metal diaphragms should be placed
in the unit so that they are facing toward the
assembler (toward the spring) except only
when one metal diaphragm is being used
then the raised surface should be facing down
(towards the body). See Figure 2 as reference.
11. Reassemble in the reverse of the above
procedures. Lubricate the upper spring seat
(key 9) and the exposed threads of the adjusting
screw (key 15) with anti-seize lubricant. Install the
cap screws (key 16) in a crisscross pattern and
tighten to finger tight only.
12. To ensure proper slack in the diaphragm, install
the adjusting screw (key 15, for Types MR95L,
MR95H, MR95HP, and MR95HT) or handwheel
(key 38, Types MR95LD and MR95HD), if
completely removed, and turn it clockwise. This
allows proper positioning of the diaphragm
(key 12) to permit full travel of the valve plug
(key 4). Finish tightening the cap screws (key 16).
See Table 7 for proper torque values.
13. Complete reassembly procedures and turn the
adjusting screw (key 15) or handwheel (key 38)
to produce the desired outlet pressure. For
Types MR95L, MR95H, MR95HP, and MR95HT,
tighten the jam nut (key 17) to maintain the
desired setting.
Replacement of Packing
(Types MR95LD and MR95HD only)
Leakage around the adjusting screw may indicate
worn packing material. Follow the instructions below
to replace the packing rings.
1. Shut down the regulator. Refer to “Shutdown”
section for the proper procedure.
2. Take out the machine screw (key 41) and lift off
the washer (key 44) and handwheel (key 38).
3. Unscrew the packing box (key 32). Unscrew the
packing nut (key 35) and the packing follower
(key 34) off of the adjusting screw (key 33).
4. Unscrew and pull the adjusting screw (key 33) out
through the bottom of the packing box (key 32).
5. Pull out the old packing (key 36) and replace
it with three new packing rings. Replace
the packing box gasket (key 37). Lubricate
packing box gasket with general purpose
Polytetrafluoroethylene (PTFE) or lithium grease.
6. Reassemble the stuffing box unit by returning
the adjusting screw (key 33) to the inside of the
stuffing/packing box (key 32). Slip the packing
follower (key 34) onto the adjusting screw and
into the packing box. Screw on the packing nut
(key 35).
7. Put the stuffing/packing box (key 32) back onto the
spring case (key 2). Set the handwheel (key 38) and
washer (key 44) on the adjusting screw (key 33) and
screw in the machine screw (key 41).
