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ANDERSON GREENWOOD SERIES 9300 PILOT OPERATED SAFETY RELIEF VALVES
InstallatIon and MaIntenance InstructIons
Field test valve “A”
Block valve “B”
Compressed nitrogen
Remote sense connection
(to tank)
Vent valve “C”
Pressure regulator w/
test gauge or manometer
FIGURE 15
4.3 Field test instructions for flowing
modulating or snap action pilots
4.3.1 General
An optional field test accessory is available
for checking the positive set pressure without
removing the valve from service. The field test
accessory consists of a 3-way ball valve to allow
the pilot to sense pressure from either the
process or from the test gas source.
A standard bottle of nitrogen equipped with
a pressure regulator, block valve, pressure
gage, and convenient length of high pressure
flexible hose is recommended for testing. A set
up similar to that shown in Figure 13 should be
used. Such a test kit is available from Anderson
Greenwood under the part number 04.4812.001
plus additional dash numbers for the pressure
gages required.
4.3.2 Field test procedure for flowing modulating
or snap action pilots
1.
Connect the gas bottle as shown in Figure 16.
2. Close vent valve “C”.
3. Open block valve “B” to supply regulator.
Note: regulator pressure should be set at 0.
4. Connect bubble tester bottle to pilot exhaust
vent.
5. Increase pressure at field test port to
slightly above tank pressure by slowly
increasing regulated pressure.
6. Open field test valve “A” and slowly increase
regulator pressure until bubbles are seen in
the bottle. That pressure will be within 10%
of the set pressure.
Note: for pilots adjusted for snap action, the
main valve seat will open at set pressure
if the tank pressure is present. If it is not,
asudden increase in pilot exhaust flow will
be observed at set pressure.
7. To remove the test set-up, close valves “A”
and “B” and open valve “C”.
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