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

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Operation
7-2
5) Check the oil pressure gauge. On start up, normal pressure is the range of 25 to 30
PSIG. A pressure of 20 to 25 PSIG will be maintained after the compressor has run
for a period of time.
6) Check the receiver/tank pressure gauge for a steady increase in pressure. The
pressure switch, which is preset at the factory, will shut the compressor off
automatically. If inadequate air pressure or air pressure greater than 150 PSIG (10.3
bar) conditions exist, refer to the air compressor manual’s Troubleshooting section.
Observe compressor operation closely for the first hour of operation and then frequently
for the next seven hours. After the first eight hours, monitor the compressor at least once
every eight hours. If any abnormal conditions are witnessed, stop the compressor and
correct the problem. After two days of operation check belt tension and lubricant level as
outlined in the air compressor’s instruction manual. Also inspect the compressor for any
leaks.
7.3 Purge the dewar
Before the initial start-up of the liquid nitrogen plant, purge the nitrogen circuit and dewar
of any contaminants. This process will ensure that only nitrogen will be present in the
dewar and its interconnecting lines. This procedure should be performed only when the
dewar is empty.
1) Thread the purging plug, supplied in the tool kit, into the end of the extraction line by
hand. Pipe sealant and wrenches are not necessary to install the purging plug.
Figure 7-1: Installing the purging plug into the extraction line
2) Make certain the extraction line valve is closed.
3) Make certain the needle valve is closed, if the N
2
generator/filter bank panel is
supplied with the optional dehumidifier and needle valve.
CAUTION
Make certain the needle valve is closed before opening the compressed air outlet
valve. The dehumidifier may rupture if it is exposed to rapid pressurization.
Dehumidifier failures resulting from rapid pressurization are not covered under the
warranty.
4) Pressurize the N
2
generator/filter bank panel by opening the compressed air outlet
valve on the air compressor.
5) If applicable, open the needle valve completely.
6) Check for air leaks in the compression fitting to the copper tubing connections at the
air compressor outlet and filter panel inlet.
7) Check the pressure gauge on the high pressure regulator. The gauge should read 85
PSIG (5.9 bar).