Taylor-Wharton XL-55HP (with dual regulators) - Manual (Page 9)

FILLING THE CONTAINER
Cryogenic liquid containers must always be filled by weight to ensure there is enough gas
head space (ullage) for liquid to expand as it warms. Using the procedure bellow, first
determine the proper filled weight of each container. The weight derived is then used in
either the Pump Transfer of Pressure Transfer filling procedures that follow.
Determining Proper Fill Weight
1. Visually inspect the container. Do not attempt to fill containers with broken or missing
components.
2. Move the container to a filling station scale and weight it both with and without the fill
hose attached to determine the weight of the fill line assembly. The difference is the fill
line weight.
3. To determine the weight, at which the fill should be stopped, add the desired filling
weight (from the table below), the transfer line weight, and the Tare Weight from the
container’s data plate.
FILLING WEIGHTS
XL-45HP XL-50HP XL-55HP XL-50VHP
ARGON 438 lb. (199 kg) 467 lb. (212 kg) 518 lb. (235 kg) 443 (201 kg)
CARBON 387 lb. (176 kg) 414 lb. (188 kg) 458 lb. (208 kg) 381 lb. (173 kg)
DIOXIDE
NITROGEN
252 lb. (114 kg) 269 lb.(122 kg) 298 lb. (135 kg) 240 lb. (109 kg)
NITROUS 368 lb. (167 kg) 393 lb. (178 kg) 435 lb. (197 kg) N/A
OXIDE
OXYGEN
360 lb. (163 kg) 385 lb. (175 kg) 426 lb. (193 kg) 364 lb. (165 kg)
Solid CO
2
(Dry Ice) Formation - Carbon dioxide may form into the solid phase (dry ice)
if the saturated pressure of the liquid is allowed to drop below 70 psig (4.8 bar/483 kPa.)
In carbon dioxide service, the pressure in a XL-45Hp/50HP/55HP/50VHP must be main-
tained above this pressure to ensure a solid block will not form inside the container. If a
container is being filled with CO
2
, it may be necessary to pressurize the container with
gaseous CO
2
before beginning the fill.
Pressure Transfer Filling Method
Filling a liquid cylinder using the pressure transfer method is common for 22 psig (1.5 bar/
152 kPa) service where the product is used for refrigerant purposes. This method may
also be used for higher-pressure cylinders to increase liquid holding time. A fill is accom-
plished by first establishing a pressure difference between source vessel and the XL-
45Hp/50HP/55HP/50VHP (higher pressure at the bulk vessel). The pressure differential
will then push the liquid from the storage vessel to the container being filled. This method
is employed when no transfer pump system is available, or if a greater control over liquid
temperature is desired.
Filling the container is accomplished through the LIQUID valve while the VENT valve is
open or partially open to control product pressure. Careful control of pressure will control
the amount of heat retained in the liquid. Lower pressure results in colder liquid trans-
ferred to the container and increases, or lengthens, product holding time.
NOTE:
The weight
calculation includes
the weight of residual
liquid and is
applicable to both
Pressure Transfer and
Pump Transfer filling
methods.
WARNING:
Filling operations
should take place only
in well ventilated
areas. Accumulations
of product gas can be
very dangerous (refer
to the safety
precautions in the
front of these
instructions). Maintain
adequate ventilation
at all times.
NOTE:
If the pressure in the
container is somehow
lost, the dry ice block
that forms may be
thawed by
pressurizing the
cylinder to 280 psig
(19.3 bar/1931 kPa)
with carbon dioxide
liquid and gas from an
external source, and
allowing several days
at this pressure to
thaw the cylinder.
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