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

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Operation
7-8
vacuum jacketed to minimize boil off losses when transferring liquid as well as helping to
protect the operator from coming in contact with extremely cold surfaces.
WARNING
The operator should be outfitted with the recommended personal protective
equipment outlined above before extracting liquid nitrogen.
Remove liquid nitrogen by opening the valve on the extraction line. When the valve is first
opened, escaping gas will be heard and a white colored vapor will be seen exiting the
end of the extraction line. Liquid nitrogen will not flow from the hose until the internal line
of the extraction hose has cooled to liquid nitrogen temperature.
When closing the valve, do not over-tighten. Once the valve stem contacts the valve seat,
light finger pressure is all that is needed to close the valve. Damage to the valve stem will
occur if the valve is over tightened. After closing the valve, the small quantity of liquid
nitrogen remaining in the extraction hose will continue to drain.
CAUTION
Damage to the valve stem and seat will occur if the valve is over-tightened.
7.7 DAILY INSPECTIONS
The liquid nitrogen plant has been designed to give continuous, trouble free service.
There are, however, daily inspections that will help detect and prevent system failure.
Observe the following list carefully.
INFORMATION
It is helpful to monitor the liquid nitrogen plant daily in order to detect changes in
performance early. These changes can signify degradation in performance that could
result from the beginning of a problem that requires attention.
7.7.1 Air compressor
•
Check and record the oil level and oil pressure. See the air compressor's instruction
manual for information.
•
Drain any accumulated water from the compressed air receiver/tank. See the air
compressor's instruction manual for information.
7.7.2 N
2
generator/filter bank
•
Check and record the pressure reading on the gauge attached to the high pressure
regulator. The gauge should read 85 PSIG (5.9 bar).
•
Check the visual indicator located on the water filter. If the indicating needle is
pointing to “CHANGE” band of the indicator, the filter elements must be changed.
Refer to Section 8.