BRAZING/DEBRAZING PROCEDURES. - TM-5-4120-383-140197

TM5-4120-383-14

BRAZING/DEBRAZING PROCEDURES.

5-13.

Brazing alloy (silver) (items 9 and 10, Appendix E)

Supplies:

Nituogen cylinder (item 8, Appendix E)

Brazing flux (item 11, Appendix E)

Abrasive cloth (item 12, Appendix E)

Rags (item 13, Appendix E)

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 connectors 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 Alloy. 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.

c. Debrazing. Debraze joints for removal of refrigeration

system components as follows:

All Refrigerant - 22 must be discharged from the

system and the entire system must be purged with dry

nitrogen before beginning any debrazing operation.

NOTE

Sometimes it may be easier to remove a component by

cutting the copper lines at accessible areas, and

after isolation of the component proceed to debraze

the copper lines from the component.

(1) Determine which joints are to be debrazed. Due to

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 joints on the component itself.

5-31