Sentry Sentry 2.0 Betreibershandbuch PDF herunterladen (Seite 46)

General Maintenance VirTis BenchTop 2K, 4K and 6K

36 Revision 004, 12/09

Scheduling Oil Changes

After clean oil is loaded into the vacuum pump and all necessary connections have

been made between the vacuum pump and the freeze dryer, perform a full capacity

test cycle.

Have a qualified technician check the oil after the test cycle. If the oil appears dirty,

change the oil after every use. If the used oil appears clean, change the oil after the

next two uses or cycles. If the oil remains clean after two cycles, change the oil after

the next four cycles. Continue to monitor the vacuum pump oil after each cycle until a

change of condition is noted or a period of one month has elapsed. If the oil remains

clean after several cycles, changing the oil once per month may be sufficient.

Vacuum Tubing and Gaskets

Inspect tubing and gaskets periodically for signs of wear. Check gaskets by removing

and inspecting interior surfaces for potential problems. A light coating of vacuum

grease on the exterior surfaces will protect gaskets and tubing. Reapply grease as

needed.

Condenser Gasket

The condenser gasket should be removed routinely and inspected for cracks.

To check the condenser gasket:

1. Remove the condenser gasket.

2. Take the gasket in both hands and turn it inside out.

3. Inspect the inside of the gasket. This is where you are most likely to find a

potential problem.

4. If you find the slightest inconsistency in the surface of the material (e.g., cuts,

cracks, dry rot, rippling), replace the gasket as soon as possible.

5. Always install gaskets on a clean, grease-free metal rim. Remove excess

grease from the metal using isopropyl alcohol on a fresh paper towel or clean

cloth. Clean the gasket with isopropyl alcohol.

6. Once the new or cleaned gasket is installed, apply a very thin coating of high

vacuum grease to the outer surface of the gasket only. The gasket should

appear moist.

Vacuum Pump Gas Ballast Valve

The gas ballast valve removes some contaminants from the pump oil. During freeze-

drying or cold trap use, vapors may bypass the condenser and end up in the vacuum

pump. If this occurs, the vapors will degrade the oil causing excessive wear and poor

vacuum pressure.

When the ballast is open, it allows a controlled amount of air into the second stage

pump cylinder. This reduces the partial pressure, increases the pump’s operating

temperature and releases the vapors.

Note: Refer to the vacuum pump manual for the location of the gas ballast valve.

1 2 ... 41 42 43 44 45 46 47 48 49 50 51 ... 55 56

Keine Kommentare

Sentry Sentry 2.0 Betreibershandbuch Seite 46