American Magnetics 430, Инструкции по установке, эксплуатации и обслуживанию

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R
EV
9
XI
A
MERICAN
M
AGNETICS
, I
NC
. F
OREWORD
: G
ENERAL
P
RECAUTIONS
Kepco BOP 20-10M 4-quadrant linear power supply (±20 V @ ±10 A)
Kepco BOP 20-20M 4-quadrant linear power supply (±20 V @ ±20 A)
Consult with an AMI Technical Support Representative for other
approved power supplies.
G
ENERAL
P
RECAUTIONS
C
RYOGEN
S
AFETY
The two most common cryogenic liquids used in superconducting
magnet systems are nitrogen (LN2) and helium (LHe). Both of these
cryogens are extremely cold at atmospheric pressure (
−
321°F and
−
452°F, respectively). The following paragraphs outline safe handling
precautions for these liquids.
Personnel handling cryogenic liquids should be thoroughly instructed
and trained as to the nature of the liquids. Training is essential to
minimize accidental spilling. Due to the low temperature of these
materials, a cryogen spilled on many objects or surfaces may damage
the surface or cause the object to shatter, often in an explosive manner.
Inert gases released into a confined or inadequately ventilated space
can displace sufficient oxygen to make the local atmosphere incapable
of sustaining life. Liquefied gases are potentially extreme suffocation
hazards since a small amount of liquid will vaporize and yield a very
large volume of oxygen-displacing gas. Always ensure the location
where the cryogen is used is well ventilated. Breathing air with
insufficient oxygen content may cause unconsciousness without
warning. If a space is suspect, purge the space completely with air and
test before entry. If this is not possible, wear a forced-air respirator and
enter only with a co-worker standing by wearing a forced-air respirator.
Cryogenic liquids, due to their extremely low temperatures, will also burn
the skin in a similar manner as would hot liquids. Never permit cryogenic
liquids to come into contact with the skin or allow liquid nitrogen to soak
clothing. Serious burns may result from careless handling. Never touch
uninsulated pipes or vessels containing cryogenic liquids. Flesh will stick
to extremely cold materials. Even nonmetallic materials are dangerous
to touch at low temperatures. The vapors expelled during the venting
process are sufficiently cold to burn flesh or freeze optic tissues.
Insulated gloves should be used to prevent frost-bite when operating
valves on cryogenic tanks. Be cautious with valves on cryogenic
systems; the temperature extremes they are typically subjected to cause
seals to fail frequently.