P2.x AMEX
4.4 Connecting the gas tubes
The pumps are delivered with customized gas connections. Please compare the part-no. on the type plate with the part-no. ex-
plained in chapter "Introduction".
Avoid mixed installations, that is connecting metal tubes to plastic bodies. If this is unavoidable for sporadic applications, screw
the metal fitting with utmost care and without any use of force to the PTFE pump body.
Install the tubes in a way that the line at the inlet and outlet is flexible over a sufficient distance (pump vibrates).
The pumps are marked with
“In”
for inlet (input) and
“Out”
for outlet (output). Make sure that the connections to the tubes are
tight.
4.4.1 Monitoring the sample gas pump
NOTICE
When following preventive maintenance according to the maintenance plan, a crack in
the bellows is a rare malfunction, but cannot be completely eliminated.
NOTICE
If the bellow cracked, turn the pump off immediately!
NOTICE
If flammable gases (even above upper explosion limit (UEL)) or toxic gases are supplied,
continuous monitoring of the pump is mandatory.
DANGER
Explosion hazard, danger of poisoning!
A crack in the bellows when conveying flammable or poisonous gasses may allow explos-
ive or poisonous gas mixtures to leak or develop.
Monitor the pump with a flow- and/or vacuum monitoring system (see flow diagram).
If a pump defect occurs, shut it off immediately.
4.4.1.1 General monitoring measures
Since a crack
in the bellow allows
the ambient atmosphere to be sucked in and the sample gas pump continues to generate
pressure,
the bellows of the sample gas pumps must be inspected regularly.
In addition, the flow rate of the pump (to the sample gas outlet) must be monitored with a suitable flow meter.
For more information or Inspecting the bellow the maintenance schedule, please refer to the chapter Maintenance at the end of
the operating and installation instructions.
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Bühler Technologies GmbH
BE420003 ◦ 08/2021
