HELIX 9600 Installation, Operation And Maintenance Instructions page 16

CTI-CRYOGENICS Helium Refrigeration System
1-2 Part Number 8040437, Revision 104, 06/12/2007, ECO Number 18068
components: the cryopump, which contains the cold head, and the helium
Compressor which compresses the helium gas.
Refrigeration is produced in the cryopump cold head through periodic
expansion of high pressure helium in a regenerative process. The high
pressure helium is provided by the Compressor. Low pressure helium
returning from the cold head is compressed into the necessary high
pressure to be returned to the cold head. The energy required to compress
the helium is rejected as heat through the cooling water.
High pressure room temperature helium is transferred to the cold head
through the supply lines. After expansion, low pressure helium is returned
to the Compressor (at or near room temperature) to repeat the cycle in a
closed loop fashion. Large separation distances can be accommodated
between the Compressor and the cryopump.
In the Compressor, helium is compressed using a highly reliable oil
lubricated commercial Compressor. Helium purification takes place via
several stages of oil removal. The final stage of purification is performed
with a replaceable adsorber cartridge. In order to maintain peak efficiency,
the adsorber must be replaced every three years. The 9600 Compressor is
shown in Figure 1-1.
©2007 Helix Technology Corporation