Cashco 1088 - Tank Blanketing - Manual (Page 3)

3 IOM-1088
To disassemble the valve, refer to the appropriate
drawings.
The working components within the valve body may be
removed without the need to take apart the diaphragm
case. To remove the body internals, simply remove
the item 032 body plug. Be careful not to drop any
components. The item 025 spring could dislodge the
item 020 spindle during removal.
To disassemble the diaphragm case, relax the
compressed spring by fi rst unscrewing the item 001
cap, then loosen the item 003 jam nut and back off the
item 002 adjusting screw. The ring of nuts and bolts
around the periphery can now be removed.
Replace all parts that show signs of damage or excessive
wear. When a part is replaced, make sure the material
is suitable for the service, especially elastomeric
components. If an o-ring needs to be replaced, be sure
to use the correct size and material (see the paragraph
on Soft Goods Kits). Prior to reassembly, make sure all
parts are clean and free of contamination and seating
surfaces are free of deep scratches.
Reassemble in reverse order of disassembly. Use tefl on
tape and/or anti-seize compound on tapered pipe thread
joints. Use lubricant sparingly on other screw threads.
DO NOT overtighten threaded connections since
damage or breakage may result. Very lightly lubricate
all o-rings with a lubricant that is compatible with the
service. Sealing surfaces of gaskets and diaphragms
may also be lubricated. Assemble with special attention
to the following:
DIAPHRAGM CASE: Use one piece of item 027 body
gasket. Be sure the item 017 center bolt is installed with
the threaded end up. There is one item 018 bolt gasket
used between the center bolt and the lower item 016
support plate as shown on the drawing. There is also an
identical gasket used between the upper surface of the
item 013 sense diaphragm and the bottom side of the
upper item 016 support plate. This is to ensure a tight
squeeze on both sides of the sense diaphragm to effect
a tight seal. Item 014 ring gasket is always installed on
the top side of the sense diaphragm. Item 033 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 the item 006 spring button. 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.
BODY INTERNALS: Before installation, be sure item
023 o-ring is placed around the groove adjacent to the
threads on the item 032 body plug. Item 021 o-ring
(smaller than item 022 o-ring) is placed around the
outside internal groove at the lower end of the spindle.
ITEMS 021 AND 022 ARE SPECIAL O-RINGS AND
MUST BE ORDERED FROM THE FACTORY.
If the valve body is installed and in the nomral upright
position, stack the components on the body plug as
follows: insert item 025 return spring into the center
cavity of item 032 body plug. Insert item 024 guide pin
inside the return spring. Place item 020 spindle over
the return spring with the small diameter tip pointing
up. Place the item 019 strainer around the spacer.
Now slowly and carefully insert the stack into the body
cavity, allowing the components to align themselves
before threading on the body plug. Tighten until snug
to bottom of the spacer.
If the valve body is on a work bench, turn the body
upside down and install the internals as follows: insert
the item 020 spindle into the body with the small
diameter tip fi rst. Insert the item 026 spacer and let it
bottom in the body. Insert the item 019 strainer around
the spacer. Insert item 025 return spring into the
spindle cavity. Insert item 024 guide pin into the spring.
Place the center cavity of item 032 body plug over the
spring and slowly and carefully push against the spring
to thread on the body plug. Tighten until snug.
After the valve has been completely reassembled,
it may be installed and put into operation as outlined
above. 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 by being forced into place.