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

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Overview
1-4
Dewar:
The dewar is a stainless steel, vacuum jacketed container built for the purpose of storing
liquid nitrogen with minimal boil off. The dewar is sealed from the atmosphere so that
only nitrogen gas flowing from the
N
2
generator can enter it. The cold head , attached to
the top of the dewar, liquefies the nitrogen gas inside the dewar.
Dewar Cord:
The dewar cord is pre-wired and fitted with electrical connectors on each end that attach
to the
dewar and helium compressor package . The dewar cord provides electrical power
from the helium compressor package to the dewar .
Extraction Line:
Liquid nitrogen is extracted from the dewar through the extraction line. The extraction line
is a vacuum jacketed, flexible, stainless steel hose. A vacuum jacketed, manually
operated valve is attached to the top of the extraction line. Liquid nitrogen is withdrawn
from the
dewar by opening the valve. The positive pressure inside the dewar pushes the
liquid nitrogen out of the dewar .
Gifford-McMahon (GM) Cryorefrigerator:
A Gifford-McMahon cryorefrigerator is a cryorefrigerator in which the cold head expands
the helium using a displacer or piston.
Helium Compressor Module:
Located inside the helium compressor package , the helium compressor module is an oil-
lubricated commercial compressor that compresses low-pressure helium to the
necessary high pressure.
Helium Compressor Package:
The helium compressor package houses the helium compressor module and all other
components that cool and purify helium and that provide system safety control. The
helium compressor package compresses the low-pressure helium returning from the
cold
head and provides clean high-pressure helium to the cold head .
Helium Flex Lines:
The helium flex lines are corrugated stainless steel hoses that transport helium between
the
helium compressor package and the cold head .
Level Indicator/Switch:
The level indicator/switch, mounted to the dewar , monitors and regulates the amount of
liquid nitrogen in the dewar . The level indicator/switch is preset to shut down the system
when the dewar is full. The user can set the liquid nitrogen level, at which the system will
automatically restart.
Nitrogen Flex Line:
The nitrogen flex line is a corrugated stainless steel hoses that carries nitrogen from the
N
2
generator to the dewar . This line only applies to Liquid Nitrogen Plant models.
N
2
Generator:
The N
2
(nitrogen) generator uses membrane technology to produce nitrogen gas from
compressed air. The nitrogen passes through the membrane while the other constituents
of air are separated out and returned to the atmosphere through a vent in the generator.
Pollution Degree 2:
Pollution degree 2 refers to the extent to which the local environmental conditions could
affect the electrical safety of the system. See EN 61010 or UL 61010A for further details.