FEI Quanta FEG 250, Руководство пользователя

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Maintenance and Troubleshooting: Pre-Vacuum Pump Maintenance
8-12
Pre-Vacuum Pump Maintenance
The Rotary pump supplied with the system is used to directly pump
parts of the vacuum system (such as the specimen chamber after a
sample exchange) and for backing the main pumping system – Turbo
Mechanical Pump (TMP).
PERIODIC CHECK
Because the pump has to process large volumes of air, loss of oil level
over time is inevitable. The oil level check should be planned every 3
months. The level indicator window is usually found on the front end of
the Rotary pump, and shows minimum and maximum level markers.
Venting the chamber shuts off the rotary pumps. Although it is
necessary when changing the total oil reserve (Service function) it is
not absolutely necessary when only topping up the oil level.
C A U T I O N !
Do not allow the pre-vacuum pump to emit gases into the work place,
as this can be a health hazard.
The Rotary pump may become very hot while in use, be careful not to
touch the main frame of the pump. Venting the chamber will shut off
the rotary pump.
Topping-Up
The filling position is a plastic hand screw stopper on the top of the
same end as the level indicator.
1. Switch off the pump if necessary by venting the chamber.
2. Unscrew the stopper.
3. Clean around the stopper hole with a lint-free cloth.
4. Fill with the recommended oil to the upper level.
5. Clean up any spillage on the pump.
6. Replace the stopper.
7. Switch on the pump by pumping the chamber.
C A U T I O N !
Never fill the pump through the exhaust hole by removing the exhaust
pipe, as this results in the oil being removed from the pump by
pressure build-up. Excessive back pressure in the exhaust pipe
eventually over-heats the pump, so it is important to allow good
passage for the exhaust gases, preferably via an installed factory
exhaust system.