Thermal vacuum chambers are used in industrial thermal vacuum
processes or for use in space research centres for scietific
experiments. In space simulation chambers materials and components
are tested and proofed.
In order fo fulfil all these requirements the SGI thermal vacuum
chamber comprises one complete functional system with thermal
shrouds, high vacuum pumping set, instrumentation and electrical
control, preassembled and workshop test.
Based on the experience of many thermal vacuum chambers SGI can
deliver systems with
The thermal system is designed to cool and to heat the shrouds
resp. to dissipate the heat of the test specimen as well as possible
energy from infrared sun simulation. SGI designs customer sized
LN2 or GN2 thermal systems for this application.
High vacuum chambers:
Horizontal and vertical arrangement
Acc. customer requirements
Degassing rate of polished surface: 6 x 10 -2 mbar l/s
Thermal shrouds and circuits:
For heating/cooling several processes are available
LN2 cooling with system open to atmosphere
GN 2 cooling/heating system using a closed circuit
Inert media cooling/heating system in a closed circuit
Data for cooling/heating with GN2 or LN2
Dissipated energy:
GN2 mode: Up to 10 kW
LN2 mode: Up to 20 kW
Encountered energy:
LN2 mode: Max. 1000 W/m2
Encountered energy:
LN2 mode: 90 K
Temperature range:
GN2 mode: 100 K-400 K
Constancy across shrouds:
GN2 mode: ± 5 K stationary state
LN2 mode: ± 3 K stationary state
Heating/cooling rate:
1 K/min
High-vacuum pump-set:
Oil-free pre- pumps and turbo- or cryo pumps
Ultimate vacuum inside the chamber: 1 x 10-7
Pump down time in the range of 10 hrs assumed
the chamber was filled with nitrogen
Operating condition:
Fully automatic test run PLC controlled
Description of SGI- Thermal vacuum chambers
The vacuum chamber is made completely of stainless steel.
The surface parts of the chamber which are exposed to vacuum
will be in a clean, metallic polished condition with a surface
emission of 
0,1.
The radiation shrouds can be made of stainless steel or copper.
The inside surface of the shrouds will be painted with two layers
black colour to get a thermal emission > O,90.
The outside surface of the shrouds will be polished to get a
thermal emittance of =
0,1.
The design of the shrouds will include proper supports, which
prevent the risk of causing leaks and thermal conductivity to
chamber wall.
The design of SGI-Prozesstechnik allows easy removal of the
shroud.
After manufacturing all parts will be checked with a He-leak detector.
The SGI thermal circuits can work within a wide temperature range
based on the use of different types of cooling/heating liquids
or the use of liquid nitrogen.
