Cryomech LNP-40, Инструкция по установке, эксплуатации и текущему обслуживанию

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Overview
1-3
1.3 Glossary
1.3.1 Definitions
The terms defined below are used with precision in the manual. For example, distinction
is made between the (helium compressor) package, and the (helium compressor)
module.
The terms are in alphabetical order, and italicized terms within the definitions are terms
that are also defined in this section.
Aeroquip
®
Couplings:
The term "Aeroquip
®
couplings" is used generically to describe the self-sealing fittings
that connect components e.g. that connect helium flex lines to the helium compressor
package and helium flex lines to the cold head .
Air Compressor:
The standard air compressor, if supplied by Cryomech, is a two stage, pressure
lubricated compressor with a horizontal receiving tank. A pressure switch automatically
maintains the compressed air pressure required by the
nitrogen generator .
Category II Installation:
Category II refers to the potential for transient over-voltage conditions in the mains power
connection to the equipment. See IEC 664, Sub-clause 5.6 for further details.
Closed Loop System:
This refers to a cryogenic system that has no helium loss because the helium is cycled
through a closed loop. The advantage of such a system is that there is no need to add
helium.
Cold Head:
The cold head is an expansion device, which is capable of reaching cryogenic
temperatures . The cold head is mounted to the top of the dewar .
Cold Head Heat Exchanger:
The heat exchanger on the cold head provides cooling at cryogenic temperatures by
transferring heat to the helium within the system.
Compressed Air Filter Bank:
A series of four filters are used to purify the compressed air before it enters the nitrogen
generator . The first two filters are designed to remove water and any bulk oil carry-over
from the compressed air stream. The third filter contains an activated carbon element to
further eliminate any hydrocarbon contaminants in aerosol form. The fourth filter traps
any carbon dust that exits the activated carbon filter.
Cryogenic Temperatures:
Temperatures lower than 120K or -153
°
C.
Cryorefrigerator (Cryocooler):
A cryorefrigerator is a cryogenic refrigeration system based upon a closed loop helium
expansion cycle. It consists of a helium compressor package , helium flex lines and a cold
head (expansion device).