Cashco 1078 - Tank Blanketing - Manual (Page 5)

5 IOM-1078
on both sides of the sense diaphragm to effect a tight
seal. Position ring gasket (014) on the top side of the
sense diaphragm. Install washers (033), lockwasher
(012) and nut (015). Torque nut 13-15 ft-lbs. Washers
are used to center the lower end of the spring. It may
sometimes be necessary to “thread” the spring onto
the washer or onto spring button (006). NOTE: You will
fi nd that turning the end of the spring in one direction
against the spring button or washers will tend to close
the coils and make installation more diffi cult. However,
turning the spring in the opposite direction will tend to
open the coils for easier installation.
PILOT INTERNALS: Before installation, ensure
o-ring (035) is placed around the groove adjacent to
the threads on pilot mount (037)(on 1” valve) or on
pilot connector (047)(on 2” valve). Install o-ring (021)
around the outside groove of the spindle (020). Install
o-ring (022) in the internal groove at the lower end of
the spindle. NOTE: O-RINGS (021,022) MUST BE
ORDERED FROM THE FACTORY.
To install the internals, turn the pilot body upside down
and insert the spindle (020) into the body with the small
diameter tip fi rst. Insert the spacer (026) and press it
down to the bottom of the body cavity. Insert return
spring (025) into the spindle cavity. Insert guide pin
(024) into the spring. Place the mounting plate (036)
around the pilot mount (037)(1” valve only). Place the
center cavity of the pilot mount (037)(1” valve) or pilot
connector (047)(2” valve) over the spring. Slowly and
carefully push against the spring to engage the threads
on the pilot mount or connector. Tighten until snug.
MAIN VALVE: Lightly lubricate all o-rings as mentioned
above. Prior to installing the fl ow plug, place o-ring
(106) on the piston (107). Install o-ring (105) in the
recess at the upper end of the fl ow plug (109). Grasp
the fl ow plug and push it into the shallow cavity of the
piston. Making sure to use the lock washer (item 112
for the 1” valve, item 012 for the 2” valve), install the
screw(111)(1” valve) or the bolt (011)(2” valve). For 1”
size torque the screw to 8-10 ft-lbs. For 2” size torque
the bolt to 13-15 ft-lbs. NOTE: The size of the fl ow plug
is stamped on the fl at end. See TABLE 1.
For 1” valves. Install o-ring (135) in the groove
inside the pilot mount (037). Next install o-ring (103)
around the groove on the piston (107). Lightly grease
the O.D. of the piston and the I.D. of the pilot mount.
Be sure that o-ring (104) is placed under the fl ange of
the pilot mount. Insert the spring (102), followed by the
piston, into the pilot mount. Push the piston in against
the spring several times to ensure there is no undue
binding. Guide the pilot mount, with the piston inside,
straight into the main body cavity. Install the four fl at
washers (041), lock washers (012) and cap screws
(011). Before the fi nal tightening of the bolts, it is a
good idea to check the tightness of the pilot mount in
the pilot body. To do so, tighten the bolts enough to
hold the pilot mount against the main body to prevent
the mount from turning. Then grasp the O.D. of the
pilot case by hand and turn it clockwise to tighten. After
tightening the mount into the pilot body, loosen the
bolts and turn the mount to orient the pilot ports in the
proper direction. Tighten the cap screws to 13-15 ft-lbs.
and reinstall all tubing. Make sure all tubing is clean
and unobstructed.
For 2” valves. Install the seat o-ring (132) in the
groove in the main body cavity. Place seat ring (131)
over the o-ring and use the four lock washers (012) and
cap screws (011). Be sure the fl at side of the seat ring
is up. Torque cap screws to 13-15 ft-lbs.
Grease the O.D. of the piston (107) and I.D. of the
piston housing (124). Install o-ring (135) in the groove
in the piston housing. Next install o-ring (103) around
the groove in the piston (107). Before placing the piston
into the main body cavity, ensure the o-ring (135) seats
properly into the piston housing and the piston can
slide smoothly in the housing. To check this, insert
the spring (102), followed by the piston, into the piston
housing. Push the piston in against the spring several
times to ensure there is no undue binding. If there is
no binding, the piston can then be removed from the
housing and placed in the main body.
Place the piston on the seat ring in the main body
cavity. Then place the spring (102) into the cavity of
the piston (107). Be sure that o-ring (104) is placed
under the fl ange of the piston housing. Carefully guide
the piston housing straight into the main body cavity,
making sure the piston slides properly into the housing.
Align the ports, and use the six lock washers (130) and
cap screws (129) to secure the housing.
Before the fi nal tightening of the bolts, it is a good idea
to check the tightness of the pilot connector to the pilot
body, the pilot connector to the piston housing, and the
alignment of the pilot ports. To do so, grasp the O.D.
of the pilot case by hand and turn it clockwise to tighten
while holding the pilot connector (047) in place. If the
pilot ports need re-positioning, use a combination of
tightening the pilot connector onto the piston housing
and/or rotating the piston housing one bolt hole.
Tighten the cap screws to 15-18 ft-lbs. Reinstall all
tubing, ensure it is clean and unobstructed.
After the valve has been completely reassembled, it
should be checked for set point pressure and any signs
of leakage. If the valve will not shut off tight, check for
dirt or other foreign particles on the o-rings or seating
surfaces. Also check to make sure the body internals
have not been damaged.