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ARMY TM 9-4120-381-14
NAVY EE-000-CA-MMA-010/7053-AC
AIR FORCE TO 35E9-136-31
5-14.
BRAZING, DEBRAZING PROCEDURES.
This task covers: Service
INITIAL SETUP
Tools:
Tool kit, service, refrigeration unit (Item 1, Appendix B)
Goggles, industrial (Appendix C)
Nitrogen regulator (Item 25, Appendix B)
Personnel: 1
Materials:
Rags (Item 12, Appendix E)
Nitrogen (Item 14, Appendix E)
Brazing alloy, silver (Item 21, Appendix E)
Brazing flux (Item 19, Appendix E)
Abrasive cloth (part of Item 1, Appendix B)
Equipment Conditions:
1.
Discharge refrigerant system (para 5-12).
2.
Purge system with nitrogen (para 5-13).
SERVICE
WARNING
All refrigerant-22 must be discharged from the system and the entire system must be purged with dry
nitrogen before beginning any debrazing operation. The polyurethane foam used as insulation in the
air conditioner will break down to form toxic gases if exposed to the flame of a torch at brazing
temperature.
NOTE
Grade IV or 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.
All tubing in the refrigeration system is seamless copper with a bright internal finish that permits thorough cleaning and
prevents entrapment of moisture and 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.
5-24
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