IOM-BQ
4
15. Insert the diaphragm subassembly into the body
(1). Rotate the assembly to ensure that the piston is
not binding in the cylinder. If nec es sary, buff piston
with Scotch-Brite
®
or equivalvent.
16. Place the range spring (11) on to the pressure plate
(10).
17. Place multipurpose, high temperature grease into
depression of spring button (12) where ad just ing
screw bears. Set spring button (12) onto range
spring (11); ensure spring button (12) is laying
fl
at.
18. Aligning the matchmarks, place spring cham ber
(2) over the above stacked parts. Install all bolts
(7) and nuts (8) by hand tight en ing. Me chan i cal ly
tighten bolting (7) (8) in a cross pattern that allows
spring chamber (2) to be pulled down even ly. Rec-
om mend ed torques are as follows:
NOTE:
Never replace bolting (7)(8) with just any
bolting, if lost. Bolt heads and nuts are marked
with speci
fi
cation identi
fi
cation numbers. Use only
prop er grades as replacements.
19. Reinstall adjusting screw (13) with locknut (14).
20. Soap solution test around bolting (7) (8) and body
(1) and spring chamber (2)
fl
anges for leak age.
Ensure that an inlet pressure is maintained during
this leak test of at least mid-range spring level;
i.e. 20-75 psig range spring, 50 psig test pres sure
minimum.
11. Clean body (1) and diaphragm
fl
ange.
NOTE:
On
regulators originally supplied as “cleaned for ox y gen
service”, Option -5, -36 or -55, main te nance must
include a level of cleanliness equal to Cashco clean-
ing stan dard #S-1134. Con tact fac to ry for details.
12. Place diaphragm gasket (6) on body (1)
fl
ange, if
required.
13. Reassemble diaphragm subassembly by plac ing
piston (3.1) in a vise (recommend using lead jaws
with vise). Assemble parts on piston cap screw (9)
as follows: pressure plate (10), diaphragm(s) (4),
and piston gasket (5), if re quired.
NOTE 1:
Apply
a light coat of gasket sealant to gasket.
NOTE
2:
Ensure that the pressure plate is placed with
curved outer rim down next to the diaphragm (4)
sur face.
14. Apply thread sealant compound to the threads
of the piston cap screw (9) and thread into piston
(3.1). Rotate pistion cap screw (9) CW and tighten
to the following torques.
C. Special Instructions for Diaphragm Re place ment:
1. For the Option -1+6 Differential Con struc tion, re as -
sem ble the diaphragm sub as sem bly in Sub-Sec tion
B. Step 12 as follows: assemble parts on piston
cap screw (9), pressure plate (10), piston gas ket
(5), diaphragm(s) (4), piston gasket (5), and push er
plate (23). Refer back to Step 13 for
"NOTES".
2. For metal diaphragm(s) (4) only, install a second
diaphragm gasket (6) on the top side of the di a -
phragm (4).
NOTE:
Clean the di a phragm
fl
ange
area of the spring chamber (2) thor ough ly be fore
assembly.
3. Utilize a new lock nut seal (22) when installing the
adjusting screw (13) and lock nut (14).
4. Install new closing cap gasket (21), re in stall clos ing
cap (20).
D. Trim
Replacement:
1. Trim removal requires that diaphragm sub as sem bly
be removed. Refer to previous pro ce dure Sec tion
VI.B.
2. Using a deep socket with a 24 inch (600mm) le-
ver length, place the socket over the cylinder (3.2)
hex sur fac es. Rotate CCW to re move the cylinder
(3.2).
3. Inspect inside surface of cylinder (3.2) at three
points:
a. Seat ring for erosion/wear on seating sur-
fac es.
b. At metal-to-metal surface between body and
cylinder (3.2). If wear exists here, consult fac-
tory.
c. Where the piston (3.1) ribbed guides bear
(guide zone).
If wear is signi
fi
cant at any of these points, replace
the piston/cylinder assembly (3).
4. Clean the body (1) cavity. Clean all parts to be re-
used.
NOTE:
On regulators originally sup plied with
Option -55, “special cleaned”, main te nance must
include a level of cleanliness equal to Cashco Speci-
fi
cation #S-1134. Contact factory for details.
5. Use special care cleaning the
fl
at mating sur fac es
of the body (1) and cylinder (3.2) shoulder, as this
pressurized joint is metal-to-metal with out a gas-
ket.
6. Lubricate the cylinder (3.2) threads lightly with
thread sealant, insert the cylinder (3.2) into the
body (1) and screw CW until tightly seated. Re-
in stall diaphragm subassembly per Section VI.B.,
Diaphragm Re place ment.
7. Bench test unit for suitable operation.
NOTE:
Reg u la tors are not tight shutoff devices. Even if
pressure falls below setpoint, a regulator may or
DIAPHRAGM TYPE
TORQUE
Metal
15 ft-lb (20 N-m)
Composition
12 ft-lb (16 N-m)
REGULATOR SIZE
BOLT SIZE
METAL DIAPHRAGM
COMP. DIAPHRAGM
ALL
5/16"
15 ft-lb (20 N-m)
12 ft-lb (16 N-m)
