4-2
180 liter LN2 Supply Tank
Thermo Scientific
Section 4
Operation
Filling Procedures
The Cryo-Cyl LP is equipped with a Liquid and Vent valve that are used
for filling. Use a pressure transfer fill as the proper filling method for this
style of cylinder. The delivery tank pressure should be as low as practical
for the transfer to be efficient. Use the following procedure.
Warning
Before making a liquid transfer, be sure that protective eyeglasses
and gloves are being worn.
1. Sample the residual gas that is in the cylinder. Purge the cylinder if
necessary to insure 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 fill valve (Item 1). 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 table.
The table indicates the product across the top and the liquid cylinder
model down the side. Connect the two columns to find the proper
weight.
Example:
The Cryo-Cyl 120 LP for oxygen at 22 psi (1.5 BAR) has a
product weight of 285 pounds (129 kg).
5. Open the cylinders vent (Item 3) and liquid (Item 1) 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 (Item 1) on the cylinder. Close the vent valve (Item 3).
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.
Caution
The transfer hose will have pressure in it that must be relieved
before the hose is completely removed.
