|
| |
TM 9-4110-257-14
5-9.BRAZING/DEBRAZE PROCEDURE. - Continued
WARNING
Never use a heating torch on any part that contains refrigerant. Heat
may cause the refrigerant to decompose and release irritating, toxic, and
corrosive gases. All refrigerant must be discharged from the system and
the entire system must be purged with dry nitrogen before beginning any
brazing operation.
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.
(3) Check that the system is being purged (para. 5-8) and apply sufficient heat uniformly around the joint to quickly
melt the filler alloy. Remove heat as soon as the joint is separated.
b.
Clean. All filler alloy must be cleaned from debrazed joints before reassembly. Heat each piece of the joint until
the filler is melted and then wipe it away with a wire brush. Be sure no filler alloy or other debris is left inside any
tubing, fitting, or component. Use abrasive cloth as necessary to clean joints.
c.
Braze.
(1) Protect wiring harnesses and other components with appropriate heat shields.
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.
(2) If brazing a joint on a valve, disassemble the valve to the extent possible and wrap all but the joint with a wet rag
to act as a heat sink.
5-16
|
