INSTALLATION
2440 Pressure and Vacuum Relief
valves must be mated with the
appropriate flange.
1/ These valves must be gasketed
and bolted to a flat machined
horizontal flange. Bolts to be
tightened uniformly to ensure a good
seal.
3/ This valve does not contain any
internal packing. Therefore internal
checks should not be necessary.
4/ It is recommended that carbon
steel and cast iron valves be given a
coat of paint immediately after
installation is complete. Apply paint to
external surfaces only.
MAINTENANCE: (During
Atmospheric Venting Period.)
WARNING
Relief valve must be isolated from
tank pressure before servicing. All
gas must be blocked and pressure
safely vented.
Wear appropriate gloves and/or
breathing apparatus if hazardous
vapours are present.
1/ Remove weatherhood (item 3) and
vacuum cover (item7), inspect o-ring
in vacuum cover for damage and
replace if necessary.
2/ Remove pallet assemblies to
inspect pallet seating for wear and
replace if necessary.
3/ To replace damaged/worn items
from pallet assembly (see
recommended spares) remove nut
from pallet stem, remove support
disc, diaphragm and backing disc
clean pallet surface and threads
replace with new parts reassemble in
reverse order
4/ Inspect valve seats (item 2) for
wear and regrind or replace where
necessary.
5/ Clean seating surface thoroughly
with suitable solvent and apply a thin
smear of light spindle oil.
6/ Generally clean inside of valve,
remove all foreign matter and repaint
exterior where possible to prevent
corrosion.
7/ Replace pressure pallet on
pressure seat and vacuum pallet on
vacuum seat (with lead disc if fitted).
8/ Replace weatherhood, secure with
hand nuts.
9/ Replace vacuum cover and replace
sealing washers if necessary, secure
with screws.
CAUTION
The end of the pallet stem must
engage the stem guide in the
weatherhood and vacuum cover to
ensure correct seating and valve
operation.
NOTE: The efficiency of the valve
depends on maintaining good seating
surfaces; therefore, maintenance
periods should be adjusted to suit
service conditions.
SPARES
When spare parts are required the
customer should quote the valve size,
serial number, the item number and
the material of the parts required.
The valve size and serial number can
be obtained from the valve
identification label. The item number
and description can be obtained from
the arrangement on page 2.
Care should be taken to quote the
correct material as the materials
quoted are for non hazardous
conditions.
RECOMMENDED SPARES
Item 10 Nitrile O-ring
Item 9 Sealing Washers
Item 14 Spacer Disc (Non Asbestos
Fibre)
Item 15 Diaphragm Backing Disc
(Non Asbestos Fibre)
Item 16 Diaphragm P.T.F.E.
