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ANDERSON GREENWOOD SERIES 9300 PILOT OPERATED SAFETY RELIEF VALVES
INSTALLATION AND MAINTENANCE INSTRUCTIONS
4 FUNCTIONAL TESTING OF COMPLETE
ASSEMBLY OF MAIN VALVE AND PILOT
4.1 General
Assemble the pilot to the main valve, and
install remaining tubing and accessories.
The complete valve assembly should be leak
tested for internal and external leaks using
a pressure equal to 30% and 90% of set.
4.1.1 Leakage check - pressure relief valves
Apply pressure to the inlet equal to 30% of
the set pressure. Check for leakage at the
main valve seat, no visible leakage shall occur.
Hold time is 1 minute.
Increase the inlet pressure to 90% of the set
pressure. Check for leakage at the cap seal,
casting, pilot support pipe and supply tube and
other applicable connections using leak test
solution and at the main valve seat. No visible
leakage shall occur for a hold time of 1 minute.
4.1.2 Leakage check - vacuum relief valves
Valves equipped with vacuum pilots shall be
leak tested per 4.1.1 on positive pressure with
the set pressure equal to the reciprocal of
the vacuum set pressure. Valves with weighted
diaphragms shall be tested for leakage at 50%
of their weighted set.
4.1.3 Back flow preventers and/or field test
The use of some field test connection or
back flow preventers necessitates the use of
check valves. These valves shall be installed
per the applicable assembly drawings and in
the free flow direction shall open at less than
.5" W.C. The check valves may be tested for
forward flow either before or after assembly
at the shops option. The output check valve of
back flow preventers shall be checked for zero
leakage per 4.1.1 paragraph 2.
4.2 Leakage check - pressure relief valves
pressure pilot (Series 400B pilot)
1. Connect gas bottle as shown in Figure 15.
2. Close 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 and block the second pilot vent if
the pilot is equipped with one.
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 3% of
the set pressure.
7. To remove the test set-up, close valves "A"
and "B" and open valve "C".
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