ABB AO2000 Series, Руководство по эксплуатации

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AO2000 CONTINUOUS GAS ANALYZERS | OI/AO2000-EN REV. B 305
Sample cell installation:
10 11
Carry out steps 20 to 22 on both sides of the sample cell in turn.
20 Insert a new O-ring seal 22.1x1.6-FFKM70
12
in the sample cell.
12
The seat of the O-ring seal may not be damaged and must be absolutely
free of oil and dust.
21 Check that the sample cell is not damaged!
Insert the cell window into the sample cell by means of the "vacuum pen"
pipette.
When doing so, take care that the cell window does not fall out and that
it is not damaged!
22 Insert a new O-ring seal 28x2-FKM80
13
into the groove of beam guide
tube.
13
Screw the beam guide tube fingertight into the sample cell.
Screw in the shorter beam guide tube
10
into the side of the sample cell,
on which the apertures of the sample gas tubing are located.
23 Hold the sample cell with 2 open-end wrenches (clamp one open-end
wrench in the vise, in order to fix the sample cell in position) and screw
in the beam guide tubes
10
and
11
as far as they will go.
Checking the sample cell for tightness:
For the assembly of the sample cell as prescribed, a leakage rate of
< 1 x 10 − 4 mbar l/s must be safely reached. This is tested as follows:
24 Seal the aperture of one sample gas tube so that it is gas-tight.
25 Connect the T-piece with shut-off valve to the aperture of the other
sample gas tube with the hose.
26 Connect the free end of the T-piece to the pressure gauge.
27 Blow air through the shut-off valve until the sample cell is under a posi-
tive pressure of p
e
≈ 400 hPa (= 400 mbar). Close the shut-off valve.
28 The pressure may not change significantly in 15 minutes at a constant
temperature. A sharp drop in pressure is an indication of a leak inside
the sample cell.