GE PM880, Руководство пользователя

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Chapter 2. Taking Measurements
Model PM880 Portable Hygrometer User’s Manual 27
2.6 Conducting a Leak Test
It is important to eliminate all leaks for safety reasons and to be sure that
measurements are not affected by ambient contamination. Use Snoop Leak
Detector or a soapy solution to verify that all connections, valves and
fittings are leak tight. Tighten any fittings where a leak is detected.
2.7 Shutting Down the Sample System
1.
Close the sample outlet needle valve.
2.
Slowly open the filter/coalescer outlet needle valve several turns to
blow out any contaminants that may have accumulated in the coalescer,
valve, or venting tube.
3.
Slowly close the sample inlet valve and allow the sample system to
depressurize at a rate of approximately 10 psig per second.
4.
Close the sample tap valve (permanently mounted on the pipeline).
5.
Crack the inlet needle valve to relieve the pressure between the sample
tap valve and the inlet needle valve.
6.
Completely close all three sample system valves.
7.
Remove the sample system from the process, while keeping all valves
fully closed to avoid moisture contamination from the ambient air.