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Technical Information
Pump used with Corrosive Gases – Pump Purging
Pump used with Corrosive Gases – Pump Purging
For pumping gases containing particulate or ag-gressive pollutants
for the bearings, the Turbo-V 750/850 TwisTorr Pumping System is
fitted with a special port (or the integrated purge/vent device
accessory) to allow a steady flow of inert gas (like He, N
pump bearing protection.
To prevent damage to the bearings, an inert gas must flow into the
pump body around the upper bearing towards the forevacuum line.
Keep the gas purge on at all times during pump operation, during
stops, and even if there is no flow of aggressive gases.
This will keep the pressure in the bearings area higher than in the
foreline and will prevent pollution or powder from flowing back,
mainly into the bearings area.
Disrespect of these simple, basic rules may cause seriously damage the pump
CAUTION!
bearings and void pump warranty.
Purging the Pump through the Standard Purge
Port – Purge Valve Installation
A gas purge valve (models: 969-9239, 969-9240, 969-9241 and 969-
9242) is available to protect the pump bearings against particulate
and corrosive gases that could move into the pump.
To supply the inert purge gas to the pump through the purge port,
connect a gas purge valve between the pressure regulator and the
pump.
To install the gas purge valve it is necessary to unscrew the standard
purge port cover as shown in the following figure.
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Turbo-V 750/850 TwisTorr User Manual / 87-901-020-01
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