Yokogawa GC8000 Process Gas Chromatograph - Manual (Page 405)

<6. Maintenance>
6-52
IM 11B08A01-01E
L9862AD Gasket 2
F0245.ai
Filter Element
Body
Nut
Bushing
Gasket 1
Gasket 2
Figure 6.45
(2) Atmospheric Pressure Balancing Valve and/or Needle Valve for
Controlling Flow Rate
See Figure 6.46.
(1) Stop the operation. (See “3.3.4 Stopping operation” for this procedure).
(2) Stop the supply of power.
CAUTION
The isothermal oven is extremely hot after turning off the power immediately. Keep the purging
air supplied for more than an hour after turning off the power. Keep hands away from the oven
components.
(3) Turn off the supply of the purging air.
(4) If the sample is liquid, purge the sample line with the purge gas (nitrogen gas or instrument
air).
• When the stream switching valve is a pneumatic valve, change the analyzer status to
Manual and turn on the stream switching valve on the sample line to let the purge gas fl ow
in.
• When the stream switching valve is a stop valve, close all the stop valves and open the stop
valve on the sample line to let the purge gas fl ow in.
(5) Close all the stream switching valves.
IMPORTANT
• During the purge, purge gas may fl ow into the sample return line, causing pressure
fl uctuation.
Prepare the sample return line and collection tank, if necessary.
• Prepare the sample return line so that the sample does not return.
2nd Edition : May 11, 2012-00