TM 9-4120-402-14
5-13. BRAZING/DEBRAZING PROCEDURES. - continued
WARNING
Never use a heating torch on any part that contains refrigerant. Heat causes the refrigerant to
break down and form carbonyl chloride (phosgene), a highly toxic and corrosive gas. All
refrigerant must be discharged from the system and the entire system must be purged with dry
nitrogen before beginning any debrazing operation.
NOTE
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.
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.
(3)
If brazing a joint on a valve, disassemble the valve to the extent possible and wrap all but the joint with a wet
cloth to act as a heat sink.
NOTE
If interconnecting tubing was removed with a component, braze tubing to the new components before
reinstallation.
(4)
Position component or assembly into place.
CAUTION
If heat is applied slowly, or only on one side, the entire component or length of tubing will be
heated and filler alloy in adjacent joints may also be melted.
(5)
Apply sufficient heat uniformly around the joint to quickly melt the filler alloy. Remove heat as soon as
brazing is completed.
NOTE
FOLLOW-ON MAINTENANCE:
5-40