CHART Cryo-Cyl80HP, Product Manual

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Operations Product Manual - Liquid Cylinders
Dura-Cyl ® MCR HP Liquid Cylinders
The Dura-Cyl MCR HP liquid cylinders are functionally
the same and only vary in capacity. They are designed to
transport, store and deliver liquid oxygen, nitrogen, argon,
carbon dioxide, or nitrous oxide as a cryogenic liquid or
gas. They can be used to transport liquid carbon dioxide
or nitrous oxide in Canada with the exemption Chart has
received from Transport Canada. The common application
for these high pressure liquid cylinders is to provide gas at
pressures around 300 psi or deliver liquid CO
2
The high
pressure liquid cylinder will build and maintain pressure
at the pressure control regulator setting of 300 psi (20.7
bar). If the pressure exceeds 325 psi (22.4 bar) the control
regulator will supply gas from the tank vapor space to the
receiving equipment which will reduce the cylinder pressure.
A continuous gas flow can be automatically provided from
these cylinders
Filling Procedures
The Dura-Cyl MCR HP liquid cylinders are regulated by
the DOT/Transport Canada for transporting liquid oxygen,
nitrogen, argon, carbon dioxide, or nitrous oxide. The filling
of these liquid cylinders must be done by product weight.
This will allow enough gas space above the liquid to keep
the liquid cylinder from becoming liquid full if its pressure
rises to the relief valve setting. The filling weight table
indicates the correct product weight for the various relief
valve settings. The standard relief valve setting is 350 psig
(24.1 barg). The filling procedure will explain the proper
way to use the filling weight table.
The high pressure liquid cylinder is equipped with a liquid
and vent valve that is used during the filling procedure. The
liquid valve is equipped with a dip tube that extends into the
inner vessel of the cylinder and reaches to the bottom The
vent valve has a dip tube attached to it that also extends into
the inner vessel of the cylinder This vent tube is designed to
spray the liquid into the top of the vessel so that pump filling
through the vent valve will keep head pressure down in the
cylinder
Filling can be accomplished by either pressure transfer or
pump fill. Follow these steps for filling Dura-Cyl HP liquid
cylinders:
1
Sample the residual gas that is in the cylinder. Purge the
cylinder if necessary to ensure the proper purity.
2
Place the cylinder on the filling scale. Record the
weight. Compare this weight to the registered tare
weight on the data plate. The difference is the weight of
the residual gas
3 Connect the transfer hose to the liquid valve Record the
new weight The difference between this weight and the
initial weight is the weight of the transfer hose
4
To determine the total filling weight add the tare weight
of the cylinder, the hose weight and the proper filling
weight from the filling table (i.e. Dura-Cyl 160 HP
for carbon dioxide at 350 psi / 24.8 bar has a product
weight of 387 pounds / 176 kg).
5
Open the cylinder vent and liquid valves. Open the
transfer line shut-off valve to begin the flow of product.
6
When the scale reads the calculated total filling weight
turn off the liquid valve on the cylinder Close the vent
valve
7 Close the transfer line shut-off valve and relieve the
pressure in the transfer line. Remove the transfer line.
Remove the cylinder from the scale
Operating Pressure
The Dura-Cyl MCR HP liquid cylinder will automatically
maintain a normal operating pressure between the pressure
building portion of the regulator (300 psi / 20.7 bar) and
the economizer portion of the regulator (325 psi / 22.4 bar).
The operating pressure can be set up or down by simply
adjusting the regulator while watching the pressure gauge.
The adjustment range of the regulators is between 150 and
350 psi (10.6 and 24.1 bar).
The gas delivery pressure should not be confused with the
vessel operating pressure. The delivery pressure should be
adjusted with a separate regulator that is attached to the gas
withdrawal fitting.
Liquid CO
2
Withdrawal
Liquid can be withdrawn from these liquid cylinders in the
same manner that was described in the Dura-Cyl LP Liquid
Cylinder section. However, the transfer of liquid carbon
dioxide is slightly different and should follow these steps:
1
Connect the transfer hose to the liquid valve fitting of
the high pressure liquid cylinder.
2 Connect the other end of the hose to the receiving
equipment.
3
Open the pressure building valve and wait for the
pressure gauge to reach the operating pressure (300 psi
/ 20.7 bar).
4
Refer to the receiving equipment manual for procedures
to open the fill valve and vent valve of the receiving
equipment.
5
Open the liquid valve on the liquid cylinder. This valve
can be adjusted to obtain the proper liquid flow rate and
delivery pressure.
6
Adjust the receiving equipment vent valve and the
fill valve to maintain pressure in the fill hose. The
equipment and the hose must maintain pressure above
70 psi (4.8 bar) during the transfer. Liquid CO
2
will turn
into dry ice at lower pressures.