Appendices
Polycold Cryochiller
Appendix F: Feedthroughs
Installation and Operation Manual
Brooks Automation
12-10
214072 Revision B
Appendix F: Feedthroughs
About Feedthroughs
Feedthrough must be selected to match the requirements of the process.
Feedthroughs are used to provide feed and return refrigerant to and from the Polycold Cryochiller cryo-
surface through the vacuum chamber wall.
One single feedthrough typically incorporates both feed and return lines for the cryosurface.
Typical Brooks Polycold feedthroughs used with the Polycold Cryochiller have a 50mm (2.0 inch) diam-
eter barrel that fits into the vacuum chamber wall. See
See
for a close-up of a
feedthrough showing the diameter of the barrel of the feedthrough that fits into the hole in the vacuum
chamber wall.
P/N 409054-00 has copper tubing. P/N 409053-00 has stainless steel tubing.
Additional feedthrough models are also available from Brooks Polycold, including single-pass
feedthroughs for 25mm (1 inch) diameter holes. A total of two such single-pass feedthroughs are
required for each cryocoil.
NOTE:
Brooks Automation Polycold feedthroughs are designed to be installed from the inside of
the vacuum chamber. This permits removal of the cryosurface when cleaning or servicing
the vacuum chamber.
Table 12-2: Specifications for Polycold Cryochiller Feedthrough
Parameter Specification
Number
228 [57mm (2.25 inches) ID X 3 mm (0.1.25 inch) section]
Material
Buna-nitrile
Surface
66mm (2.60 inches)
Surface roughness not to exceed 0.81 micron (32 micro-inch 0.000032 inch)
Must be flat, clean, and free of scratches or deposits.
