BRAZING/DEBRAZING PROCEDURES. - continued
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
All joints, except those provided with flare fittings, are made by brazing in
accordance with MIL-B-7883, except that radiographic examination is not
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
(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.
If interconnecting tubing was removed with a component, braze tubing to the
new components before reinstallation.
(4) Position component or assembly into place.
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.