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a. Close the internal valve and exhaust
downstream pressure. Close the first valve
downstream from the internal valve and note
any pressure buildup, using a pressure gauge,
between the closed valve and the internal
valve. If piping is cold allow it to warm to
ambient temperature.
b. Refer to CFR 49 Section 180 Appendix B for
Meter Creep Test Methods.
3. All operating controls should be regularly
inspected and cleaned and oiled. The controls
should be checked to see that they fully open—but
not over-travel—the internal valve and operate
freely to close the valve.
4. Standard construction internal valves must be
removed if the container is to be steam cleaned.
Heat can damage the valve's seats and seals.
5. Standard construction internal valves are not
designed for water service. Immediately after
a container is hydrostatically tested, remove
all water and allow the container to thoroughly
dry out.
Disassembly
WARNING
!
Tank pressure must be released before
removing the valve from the container.
Failure to do so could result in
personal injury.
Numbers in parenthesis refer to key numbers in
Figure 5.
To Replace Packing
1. The packing can be replaced with product in the tank
by closing the operating lever (key 16) and blowing
down the downstream pressure in the system.
2. Remove the two cap screws (key 17) holding the
gland assembly and cover plate to the body.
3. Rotate the entire gland assembly slightly
counterclockwise and turn the assembly to the left
as it is pulled out of the body.
4. Unscrew the cap screw (key 15R) from the stub
shaft (key 15J) and remove the operating lever and
cover plate by taking out the cotter pin (key 19).
5. Pushing on the stub shaft will expose the gland
parts including the spacer (key 15W) and packing
(keys 15F, G and H).
6. Besides the packing, the liner bushings (key 15B)
should be replaced.
7. Reassemble in reverse order. Replace cap
screw (key 15R) using 30 to 35 in-lbs / 3.3 to
3.9 N•m torque.
8. Make sure the operating lever can move freely
after the new parts are installed. Conduct a leak
test under pressure with a soap solution.
To Replace Seat Discs
1. Remove the valve from the tank and take out the
gland assembly, refer to steps 2 and 3 above.
2. Holding the stem (key 2) with a 5/8 in. / 15.9 mm
socket, unscrew bleed seat (key 13) from
the stem.
3. Place the disc holder (key 6) into a vise with
a shop towel over the vise. The vise must be
tightened lightly and carefully so as not to bend
the disc holder. Unscrew the disc retainer (key 8)
to reach the main seat disc (key 4) and the bleed
seat disc (key 11).
4. Examine both seat discs and replace if necessary.
To ease installation place the bleed seat disc on
top of the disc retainer before screwing the disc
retainer into the disc holder.
5. If the excess flow spring (key 3) is changed,
replace the nameplate or stamp the body with the
new type number.
6. Reassemble in reverse order using 35 to
40 in-lbs / 4.0 to 4.5 N•m torque to install the
disc retainer. Apply Loctite No. 242 or equivalent
on the stem threads before installing the bleed
seat (key 13).
Parts Ordering
When corresponding about this equipment, always
reference the equipment type number found on the
nameplate. A replacement Parts List is available
for the valves. When ordering replacement parts,
reference the complete 11-character part number for
each needed part.
Type C407-10
7
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