Ametek WDG-V, Руководство пользователя

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PN 9000-133-VE, Rev U
Sniffing for Leaks
For processes under vacuum, you can check for leaks by sniffing the fittings
with another gas (for example, nitrogen or pure oxygen), being sure to avoid
the area over the top of the cell.
1. Use a piece of tygon or plastic tubing with a 1/8” stainless steel nozzle to
apply the gas from a cylinder (using stainless steel prevents any problems
that might occur with plastic melting the nozzle on hot analyzer compo-
nents).
2. Monitor the response from the cell. When the cell millivolt reading chang-
es, it indicates a leak in that area of the plumbing (the vacuum of the
process pulls in the gas).
3. If not convenient to view the display, you can also apply a voltmeter to the
Cell terminals on the
Sensor
board la beled (
+O
2
-
) t o see if the cell milli-
volts change, indicating a leak.
Pressurizing for Leaks
1. Remove the analyzer from the process (after allowing analyzer to cool) and
pressurize it with 5 lb of air, plugging any exiting ports, the inlet probe, and
exhaust tube holes. Then go over the analyzer fittings with a leak detector
fluid.
2. If you see bubbles, it indicates a leak. If using this method be sure to
prevent the liquid from reaching the furnace. If the furnace does get wet,
allow it sufficient time to thoroughly dry.
Plugged Plumbing Check
Exercise care when working on the analyzer. Allow the unit to cool and
wear gloves.
1. Examine the inlet and exhaust for plugging problems. When possible, rod
out the probe and exhaust.
2. If this doesn’t solve the problem, disassemble the analyzer to locate the
plug. Clean the plumbing using hot water and a bottle brush.
3. When assembly is complete, check for leaks using a leak detecting liquid.
Maintenance and Troubleshooting
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