Sumitomo HC-4A, Technical Manual

Page: 9 / 72

Safety
3
CAUTIONS (continued)
AVOID GAS LEAKS. Check the condition of the gasket face seal on the male half of each
Aeroquip coupling. Be sure the gasket face seal is in place and the sealing surfaces on both
the male and female halves are clean before connecting. Replace the gasket face seal if it is
damaged or missing.
Keep the gas line couplings aligned when making or breaking a coupling connection. Leaks can
occur due to the weight of the gas line or due to a sharp bend near the connection.
AVOID CONTAMINATION.
When checking the compressor for shipping damage, do not
connect gas lines and cold head. The components may become contaminated with
compressor oil.
Follow the charging or venting procedures to prevent reversed flow of system gas. Do not
charge through the supply coupling. Do not vent through the return coupling. Reversed flow
can contaminate the system with compressor oil.
A leaking coupling on an adsorber should not be repaired in the field. Consult a Service Center.
Venting the adsorber will introduce contaminants to the system, which cannot be removed in the
field.
PREVENT EQUIPMENT DAMAGE. Damage to gas lines can result from crimping by repeated
bending and repositioning.
Never pull a vacuum on the compressor or on the cold head. The motors will short circuit if
started.
AVOID A MALFUNCTION. Repeatedly charging the system with helium gas rather than
locating and repairing gas leaks can cause a malfunction. Impurities are introduced at an
abnormal rate and can freeze in the cold head.
Do not allow air to get into the helium gas refrigerant of the system. Moisture from the
atmosphere can seriously degrade cold head performance.
AVOID EQUIPMENT FAILURE, CONTAMINATION OR A NUISANCE SHUTDOWN. Do not
tip the compressor greater than 5 degrees from horizontal, to avoid flowing oil into unwanted
places.