TM 9-4120-403-14
5-9. BRAZING/DEBRAZING PROCEDURES
INITIAL SETUP
Tools
General Safety Instructions
Tool Kit, Refrigeration
(Appendix B item 1)
WARNING
Nitrogen Regulator
All refrigerant -22 must be discharged from system
and entire system must be purged with dry nitrogen
Materials/Parts
before beginning any debrazing operation.
Rags
(Appendix E item 1)
Polyurethane foam used as insulation in air condi-
Nitrogen
tioner will break down to form toxic gases if exposed
to flame of a torch at brazing temperature.
Brazing Alloy
Brazing Flux
Abrasive Cloth
Equipment Conditions:
Refrigerant System Discharged (para 5-7)
Refrigerant System Purged (para 5-8)
a
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.
b
Filler Allo. Grade IV and VI brazing alloy and Type B flux, as specified in MIL-B-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.
c
Debrazing. Debraze joints for removal of refrigeration system components as follows: (1) Determine
which joints are to be debrazed. Due to the limited work space inside the air conditioner, it may be more convenient to
remove a part of the interconnecting tubing with the component rather than debrazing the joints on the component itself.
5-18
