RS COMPACT FREEZE TUNNEL, Руководство по эксплуатации и обслуживанию

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OPERATION & MAINTENANCE MANUAL
CompactFreezer
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best efficiency of the cryogen. The circulating fan must be operating; otherwise the high velocity gas will
not repeatedly pass the cryogen over the product to enhance the cooling effect. If the product being
frozen is very flat or light, the circulating fans may cause the product to lift off the belt. This can cause
product damage. Do not stop the circulating fans, as this will significantly affect the efficiency of the
Cabinet Freezer . Alternatively, run the variable speed fans at a lesser speed. If this is not possible (fixed
speed fans) or not enough, the blades of the circulating fans can be changed to a shallower pitch that
should not cause lifting of the product off the belt.
6.4. FREEZER CONTROL VARIABLES
The variables the operator controls to obtain the most efficient freezer performance are:
a. Conveyor speed
b. Temperature
c. Fan speed (optimal)
For each product, there is an optimum setting for each of these two variables for a given set of
circumstances (production rate, input temperature, output temperature, etc.). Once determined, these
settings should be established as standard for that product.
Generally, it is recommended that the conveyor be run at the slowest speed that will handle the required
production, and then increase the freezer operating temperature to the warmest temperature that will
produce the desired results. This is the most economical method of operation.
Quite often, the speed of the conveyor is established by production from an automatic feeder of a meat
patty machine, etc., and then the only variable left to control is the temperature. This should still be set
as warm as possible to obtain the desired degree of freezing.
The freezer conveyor belt should be loaded with the product full across its width and to the greatest
density practical.
Here too, the product loading on the freezer conveyor may be determined by upstream production
equipment. The product may be produced in rows that just fit across the freezer conveyor. Then the
conveyor speed should be adjusted for minimum practical spacing between the rows. A shuttle conveyor
may be required to change product coming to the freezer in single file, to rows across the freezer
conveyor belt. Product random loaded on the freezer conveyor may require infeed equipment such as
vibrating conveyor, etc.
Variable speed fans – This option provides another control for the freezer operator. A standard fan
speed setting can be established for light weight or heavy items to take advantage of the heat transfer
improvement contributed by velocity of the cold LN2 vapor circulating over the product.