TM 9-4120-399-14
5-9. BRAZING/DEBRAZING PROCEDURES.
WARNING
DANGEROUS CHEMICAL
(R22)
is used in this equipment.
DEATH
or severe injury may result if personnel fail to observe safety precautions.
Use great care to avoid contact with liquid refrigerant gas being discharged
under pressure. Sudden and irreversible tissue damage can result from
freezing. Wear thermal protective gloves and a face protector or goggles
in any situation where skin-eye-contact is possible. Prevent contact of
refrigerant gas with flame or hot surfaces. Heat causes refrigerant to
break down and form carbonyl chloride (phosgene), a highly poisonous
and corrosive gas.
WARNING
REFRIGERANT UNDER PRESSURE
is used in the operation of this equipment.
DEATH
or severe injury may result if you fail to observe safety precautions.
Never use a heating torch on any part that contains refrigerant 22. Do
not let liquid refrigerant touch you, and do not inhale refrigerant gas.
a. Supplies. To perform any brazing or debrazing procedures, you will need the following
items.
Brazing alloy (silver) (Appendix E, items 3)
Nitrogen cylinder (Appendix E, item 2)
Brazing flux (Appendix E, item 5)
Abrasive cloth (Appendix E, item 7)
Rags (Appendix E, item 8)
Heat Sink (Appendix E, item 21)
b. General. All tubing in the refrigeration system is seamless copper with a bright internal
finish that permits thorough cleaning and prevents entrapment of moisture or other impurities.
Rigid grade copper is used for straight sections and soft grade for sections that must be bent.
All interconnecting fittings, such as elbows, tees, etc., are also copper. The bodies of all valves
and all connections on other components are brass. All joints, except those provided with flare
fittings, are made by brazing in accordance with MIL-B-7883, except that radiographic
examination is not required.
7883, must be used for all copper to brass joints. Grade III brazing alloy may be substituted for
Grade IV or VI for copper to copper joints; flux is not required for copper to copper joints.
