Cashco 31-B - Manual (Page 4)

IOM-31-B 4
SECTION VI
VI. MAINTENANCE
A. General:
1. Maintenance procedures hereinafter are
based upon removal of the regulator unit
from the pipeline where installed.
2. Owner should refer to owner’s procedures for
re mov al, handling and cleaning of re us able
parts, the dis pos al of non-reusable parts, i.e.
gaskets, suitable sol vents, etc.
3. If desired, gaskets may be oiled, or coated
with gasket sealant or thread sealing com-
pound, provided the sealant is compatible
with the process fl uid.
4. Regulators originally supplied as “special
cleaned" (Opt-56) are assembled using
special seal ant, Floramics "Formula 8",
or equivalent. Cash co, Inc., rec om mends
fol low ing factory cleaning specification
#S-1542, or equiv a lent. Contact factory for
details.
5. When directions such as upwards, down-
wards, leftwards or rightwards are given,
they are with respect to Figures 5 and 6.
When counter clockwise (CCW) or clock wise
(CW) ro ta tions are indicated, they are with
respect to:
a. Spring Chamber – as viewed from above
looking down towards the closing cap
or its normal location.
b. Body – as viewed looking into the body
cavity with the upper case assembly
re moved.
B. Diaphragm Replacement:
1. Install body (1) securely in a vise with the
spring chamber (4) oriented upwards.
2. Remove closing cap (5). Relax range spring
(17) by turning adjustment screw (18) CCW;
count the number of revolutions to remove
adjusting screw from upper case and record
in following box.
No. of revolutions to remove ad just ment
screw (18) ____________________ .
3. Paint or embed a match mark between lower
case (3) and spring chamber (4) at fl ange
O.D.
4. Remove all diaphragm fl ange nuts (10) and
case screws (9).
5. Lift spring chamber (4) and range spring (17)
upwards to remove.
6. Pry up the edges of the diaphragm (12) from
around the pe rim e ter of the lower case (3)
diaphragm fl ange to assure that the dia-
phragm is not “sticking” to the lower case.
7. Grasp stop post (19) with hand and carefully
lift up wards and to the right to disengage
linkage lever (21) from cir cu lar opening of
lower di a phragm plate (20). See Fig. 5. Fully
remove diaphragm sub-assembly (DSA)
from lower case.
8. Place the “ear” of the lower diaphragm plate
(20) into a soft jawed vise and secure tight.
(Stop post (19) should be pointed upwards.)
Paint a match mark on the top surface of
the upper diaphrgm plate near the O.D. to
mark the location of one of the diaphragm
bolt holes.
9. Place a wrench on the hex surface of stop
post (19) and rotate CCW. Hold upper dia-
phragm plate (13) with fi n gers so it doesn't
fall and continue to loosen stop post (19)
until post is free. Remove washer (16), and
nylon bushing (15). Lift upper diaphragm
plate (13), together with stuck-on diaphragm
(12) away from lower diaphragm plate (20),
and place on bench top.
10. While holding upper diaphragm plate (13) in
the palm of hand, hand-pull diaphragm (12)
up to loosen from upper di a phragm plate .
NOTE: The diaphragm (12) is adhered to the
WARNING
SYSTEM UNDER PRESSURE. Prior to performing any
maintenance, isolate the regulator from the system and
relieve all pressure. (Including the External Sensing
line when specifi ed.) Failure to do so could result in
personal injury.
WARNING
SPRING UNDER COMPRESSION. Prior to re mov ing up-
per case, relieve spring compression by removing the
ad just ing screw. Failure to do so may result in fl ying parts
that could cause personal injury
.