1.4. Vacuum Operation
There are two vacuum preparation options:
l
Low Vacuum (for use in atmospheric pressures to 10
-3
Torr)
l
High Vacuum (preparation for environments from 10
-3
to 10
-6
Torr).
Special preparations include:
l
Parts are lubricated with vacuum-compatible lubricants.
l
Materials, fasteners, and coatings are selected to be compatible with the specified level of
vacuum.
l
High-vacuum systems are designed to eliminate trapped volumes.
l
Prior to assembly, stage parts are thoroughly cleaned in a clean environment.
l
The stage is packaged in a special polyethylene bag.
Vacuum Guidelines
To ensure that the stage will continue to perform well in the vacuum environment, use the
guidelines that follow (in addition to standard handling, installation, and lubrication guidelines
outlined in this manual).
1. Do not remove the stage from its sealed bag until it is ready to use.
2. Always handle the stage in a clean environment and use powder-free polyethylene gloves to
prevent any contaminants from adhering to the surface of the stage.
3. During installation, use cleaned, vented, stainless steel fasteners to secure the stage.
4. Reduced air pressure eliminates significant convective heat transfer. This, coupled with the
viscous vacuum-compatible lubricants, could result in excessive motor operating temperatures.
Because of this, consider all continuous torque ratings to be
40 to 60% lower
than the value
specified for operation in normal atmospheric environment. Reduce motor usage accordingly.
5. We recommend that you use a small quantity of
Braycote® 602EF
grease or a compatible
substitute of equal quality lubricant in vacuum applications.
6. To reduce outgassing during the initial pump-down to vacuum pressure, Aerotech recommends
that you bake out vacuum systems when you first install them into the vacuum chamber. Bake
the vacuum components at 60 °C for 24 to 48 hours to desorb water vapor from surfaces and
degas polymers (such as cable insulation).
1.4. Vacuum Operation
ECO165SL Hardware Manual
20
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