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VAREC 7100B SERIES PRESSURE RELIEF VALVE
INSTRUCTION, OPERATION AND MAINTENANCE MANUAL
3. To load pallet weights perform the following:
a) Remove pressure pallet assembly
from body.
b) Remove grip ring from pallet stem.
c) Non-variable setting: Locate weight
marked "PRESSURE" and place on top
of compensating weight and/or pallet.
Secure with grip ring. If setting is less
than 2" WC, weight will be pre-loaded on
the pallet.
d) Variable setting: each lead weight
is calibrated from 1" WC increment.
(Increments of ¼" WC and ½" WC may
be supplied on special order). Those
weights necessary for the initial specified
setting will be tagged separately from
any extra weight provided. Remove the
packaging on the weights tagged for the
initial specified setting and place the
weights on top of the pallet. Secure with
grip ring. Store remaining weights for
future use (in case the setting needs to
be increased).
e) Weigh entire pallet assembly (including
installed weights). Using the Calibration
Table, confirm that the assembly is the
proper weight to achieve the required
setting. Allowable weight tolerance is
+5%,-5%.
f) Remove any remaining packing material
from valve body. Wipe pressure seat ring,
guide posts and pallet assembly with a
soft cloth to remove any material which
could affect valve operation.
g) Place pallet assembly on valve body
seat. Ensure that pallet moves freely
within guide posts and rests flat on the
seat ring.
h) Replace the weatherhood and tighten all
nuts uniformly.
CAUTION
The end of the pallet stem must engage the stem
guide in the weatherhood for proper seating and
valve operation.
4. Place the valve in a level position. Check the
pallet operation by reaching up through the
inlet flange and carefully pushing up on the
pressure pallet, then lowering it onto the
seat. Pallet should move up and down freely
and rest flat on the seat ring.
5. Mount the valve on the flanged nozzle or
flame arrester using the appropriate full
faced gasket.
CAUTION
DO NOT MATE A FLAT FACE FLANGE TO A
RAISED FACE FLANGE.
If it necessary to mate a flat face flange with
a raised face flange, use the proper spacer to
convert the raised face to a flat face.
6. Verify that the valve is level to permit proper
operation of the pallet. Install mounting
hardware, and tighten uniformly.
NOTE
It is recommended that steel valves be given a coat
of paint immediately after installation is completed.
Apply paint to external surfaces only.
MAINTENANCE (ASSEMBLING AND
DISMANTLING)
The valve should be inspected and cleaned
at periodic intervals. The first inspection
should be made approximately 30 days after
commissioning. Subsequent inspections should
be made every 30 days. The user may adjust the
schedule for his own convenience and safety,
depending upon the product being stored.
WARNING
• Relief valve must be isolated from tank pressure
before servicing. All gas must be blocked and
pressure safely vented. If no isolation valve is
present, carefully lift pallet, allowing pressure
to vent slowly.
• Wear appropriate gloves and/or breathing
apparatus if hazardous vapors are present.
1. To inspect valve, proceed as follows:
a) Remove weatherhood and then the
pallet assembly.
b) Inspect pallet inserts for ripples, tears,
or nicks, as well as seating surfaces for
debris, abrasion or pitting. Pallet edges
and guide posts should be free of burrs,
corrosion or other obvious damage.
Clean all components, replacing any
showing excess wear or damage. On
the "All-Weather" versions, inspect the
PTFE coating for any damage that would
affect operation.
c) Reassemble in reverse order.
CAUTION
The end of the pallet stem must engage the stem
guide in the weatherhood for proper seating and
valve operation.
CAUTION
During periods of freezing weather, extra
maintenance is required for 7100B Series. Either
remove the pallet or apply generous portions of
silicone grease to the pallet, seat ring and guide
posts. When using silicone grease, inspect valves
at least weekly. This procedure is not required for
the "All-Weather" Model 7101B.
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