CHART Cryo-Cyl80HP, Руководство по эксплуатации продукта

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14
Introduction Product Manual - Liquid Cylinders
When the pressure falls below the pressure building regulator
setting (125 psig), the regulator will open (Figure 14). This
will allow liquid to run into the pressure builder vaporizer
located at the bottom of the tank The liquid will turn into gas
and be delivered back into the top vapor space of the tank.
The results of this operation are a rise in pressure in the tank.
Figure 14
Liquid Withdrawal
If the liquid cylinder is to be placed in permanent liquid
withdrawal service, it is recommended that the cylinder be
fitted with a 22 psig relief valve to minimize loss due to
flash-off.
Note: In the Dura-Cyl
®
HP/Cryo-Cyl
®
HP Liquid
Cylinders the pressure must be kept above
70 psig for CO
2
to prevent solidifying the
CO
2
.
Caution! Before making a liquid transfer,
be sure that protective eye
glasses and gloves are being
worn.
To withdraw liquid from a liquid cylinder, connect a transfer
line from the liquid valve fitting to the user's receiving vessel
(Figure 15). Open the liquid valve to obtain the preferred
rate of flow. Close the liquid valve when the user's vessel
has been filled. To prevent contamination, when the cylinder
has been emptied, all valves should be closed. To minimize
flash-off and spillage, use a phase separator on the end of
the transfer line. Normal liquid withdrawal operations are
performed at lower pressure (approximately 22 psig) to
reduce flash-off losses and splashing. For this reason, the
pressure building valve is customarily closed during liquid
withdrawals. Transfer of liquid at higher pressure can lead
to excessive splashing of the cryogenic liquid which could
result in burns to the operator and/or nearby personnel.
All personnel should be fully instructed in the cautions
associated with handling cryogenic fluids and the proper
clothing and protective gear to be used.
If a higher operating pressure is desired (other than that
available through normal heat leak), the pressure building
valve may be opened for a short time until the preferred
pressure has been obtained. If automatic pressure building
for liquid service is necessary, a low pressure building
regulator may be installed to replace the pressure building
regulator supplied with the unit.
Figure 15
Liquid carbon dioxide, used for freezing or cooling can be
completely withdrawn from a Dura-Cyl HP/Cryo-Cyl HP
liquid cylinder, leaving just 2% residual gaseous product.
Connect a transfer line from the liquid fitting of the liquid
cylinder to the receiving vessel. Open the liquid valve to
obtain the desired rate of flow.
The Dura-Cyl HP/Cryo-Cyl HP liquid cylinder will deliver a
continuous flow of liquid CO
2
at rates of 1,000 pounds/hour
or greater, having a refrigeration content of 119 BTU/pound
at 350 psig. Leave the pressure building valve open for high
withdrawal rates