rangerssuck wrote:



So, given that I have a system that's shut down and pumped out, and that I
can isolate the rink floor pipes from the rest of the system and there are
service valves accessible, does anyone know how I might determine the
volume of these pipes?
Pumped out as in evacuated? Get an industrial-size gas meter in working
condition. Connect to the evacuated system with a throttleing valve.
Record the gas meter's dial reading. Open the throttling valve slowly until
the moter starts turning. As the pressure in the pipes comes up, open the
valve more and more to keep the meter chugging along at a safe rate. When
the meter stops moving, you have the volume in cubic feet, roughly STP.

If you fill the system with a known pressure of gas, then vent out through
the meter, you will expand the gas in the system until it reaches
atmospheric pressure. If you filled it to 15 PSIG, then assuming an ideal
gas, venting to atmospheric pressure should release as much gas as the
system holds at atmospheric pressure, so again the reading = volume.
If you pressurize it to only 1 PSIG, then the meter reading would be 1/15th
of the actual volume. (All figures for sea level, not Denver.)



Jon