RS COMPACT FREEZE TUNNEL, Руководство по эксплуатации и обслуживанию

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OPERATION & MAINTENANCE MANUAL
CompactFreezer
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It is recommended that the LN
2
‐ supply line is purged before final hook ‐ up to the freezer by opening the
main supply valve at the tank slowly. Purge the LN
2
‐ line for approximately 30 seconds, and then close
the main supply valve.
5.3. EXHAUST SYSTEM INSTALLATION
The freezer exhaust system, if properly installed and tuned, will ensure an efficient removal of all
superfluous nitrogen gas.
Note the following prior to installation of the exhaust system. It is recommended that the exhaust
system is designed and installed by qualified personnel only.
•
Design the exhaust ducting to facilitate cleaning and inspection. Stainless steel ducting is
recommended, though PVC ducting is commonly used.
•
Provide adequate make‐up air in the production area. This will allow for proper exhaust system
performance and reduce negative pressure in the production area.
•
Protect the exit of the exhaust system against bad weather conditions and/or birds.
•
Minimize the length of the exhaust ducting and the number of turns.
IMPORTANT: The exhaust system must be sized for the typical ambient and operating conditions of the
freezer.
5.4. TUNING OF AMBIENT AIR INTAKE
Ambient air is required to prevent the exhaust duct and fan from falling below 32°F (0°C) and causing
ice build
‐ up due to the humidity in the air.
The amount of ambient air required will depend on the ambient air temperature. In case of a non ‐
refrigerated room (70°F/21°C, 70% relative humidity), normally 3 to 5 volumes of air is diluted with one
volume of nitrogen gas generated in the freezer.
If the freezer is located in a humid, refrigerated room (40°F/4.5°C, 50% relative humidity) the air dilution
must be increased to 7 up to 9 volumes of air per volume of nitrogen generated in the freezer.
l
i