11
5.3.3. PRESSURE RELIEF VALVE
5.3.3.1. USING 1/8 INCH COPPER TUBING, CONNECT THE CALIBRATED
PRESSURE GAUGE BETWEEN THE HELIUM TANK AND THE GAS INPUT
SWAGELOCK CONNECTION LOCATED ON THE SIDE OF THE
STEREOPYCNOMETER .
5.3.3.2. THE
PRESSURE RELIEF VALVE IS LOCATED IMMEDIATELY BEFORE THE
INPUT FLOW CONTROL NEEDLE VALVE INSIDE THE STEREOPYCNOMETER.
ADJUSTMENTS WILL BE MADE SO THE PRESSURE IS RELIEVED IF THE TANK
PRESSURE EXCEEDS 25 PSIG. AT 25 PSIG THE RELIEF VALVE WILL ACTUATE
AND THE GAS WILL BE VENTED, AFTER WHICH REMOVE THE GAS INPUT LINE
MOMENTARILY TO ALLOW THE PRESSURE RELIEF VALVE TO RESET
5.3.3.3. USING A 5/16 HEX ALLEN WRENCH, SET THE RELIEF VALVE TO JUST
STOP AT 25 PSIG. CHECK THE SETTING BY SUBMERGING THE END OF THE
RELIEF VALVE IN A BEAKER OF WATER, IN ORDER TO VERIFY THAT NO
BUBBLES ARE FORMED AT 25 PSIG. INCREASE THE TANK PRESSURE AS
DISPLAYED ON THE CALIBRATED PRESSURE GAUGE TO 26 PSIG AND VERIFY
THAT BUBBLES APPEAR IN THE BEAKER.
5.3.3.4. TIGHTEN THE OUTER LOCKING NUT UNTIL IT MEETS THE INNER NUT.
APPLY A MODERATE AMOUNT OF TORQUE SEAL TO THE OUTER NUT. NOTE
THAT AN EXCESSIVE AMOUNT OF TORQUE SEAL WILL BLOCK THE RELIEF
VALVE.
5.3.3.5. ADJUST THE TANK PRESSURE REGULATOR TO DELIVER SLIGHTLY
ABOVE 20 PSIG.