Ulvac CRYOPUMP CRYO-U Series Instruction Manual page 73

CRYO-U Cryopump Instruction Manual
®
Cryopump
５． Reduce the pressure in the refrigerator unit and the flexible hoses to a level of 0.3MPaG by
opening the valve(V1) of the charging adaptor.
NOTE:
As refrigeration lowers the temperature of helium gas in the refrigerator unit, the density of
the gas increases. After shutdown of the refrigerator, the temperature of the helium gas in
the refrigerator returns to room temperature from cryostatic temperature gradually, and the
inner pressure rises at the same time. The unit has a pressure relief valve which opens at
the inner pressure of 1.9MpaG and more. If once the pressure relief valve opens, it could
cause a leakage that would depend on the surrounding environment such as dust.
Therefore, ensure to reduce the inner pressure right after shutdown of the refrigerator in
order not to work the pressure relief valve.
Cryopump
Coldhead Cable
Disconnect here
Flexible Hose
ＳＵＰＰＬＹ
ＲＥＴＵＲＮ
Figure 8-2 Disconnecting Flexible Hoses
Flexible Hose
XXXXXXXX
******
Coldhead Cable
Figure 8-3 Connecting Charging Adopter
ULVAC CRYOGENICS INCORPORATED
ＩＮＰＵＴ ＰＯＷＥＲ
ＣＯＬＤ ＨＥＡＤ ＰＯＷＥＲ
ＲＥＭＯＴＥ
ＮＯ．１ ＮＯ．２ ＮＯ．３
ＲＥＳＰＯＮＳＥ
Power Cable
ＲＥＴＵＲＮ ＧＡＳ ＲＥＴＵＲＮ ＧＡＳ ＳＵＰＰＬＹ ＧＡＳ
ＷＡＴＥＲ ＩＮ
ＷＡＴＥＲ ＯＵＴ
ＯＵＴ
Charging Adopter
Ｖ２
ＳＵＰＰＬＹ
Ｖ１
ＲＥＴＵＲＮ
Ｖ３
ＩＮ
Cooling Water Line
Release He gas
Release He gas
8-9