S 948-365
(2)
Cut out the damaged section of the tube:
(a)
Make sure the section you cut out of the tube is a straight section with a minimum straight length as shown in Fig. 826. This will make sure the fitting and swage tool will fit.
(b)
Use one Permaswage fitting for the repair if the damaged section is no more than 0.150 inch long. In this case, the cut can be through the center of the damaged section.
(c)
If the damage is too near to a bend (less than 1/2 "A", Fig. 826) or longer than 0.150 inch, use a tube splice and two fittings to make the repair.
S 948-366
(3) For tube cutouts with a bend, use the cutout tube section as a template to mark and cut the new tube segment.
NOTE: The maximum gap between the tube ends is approximately 0.150
____
inch for the union installation.
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(4) Clean the tube in the swage area:
(a)
Clean the not painted tube sections that you will repair with solvent, Series 80 (AMM 20-30-80/201).
(b)
Make sure the sections are free of dirt, grease, and other unwanted material for a distance equal to the values shown in Fig. 826.
(c)
Remove paint and anodize from the tubes in an area equal to the values shown in Fig. 826. Use the methods shown in Fig. 828.
(d)
Make sure the cleaned surfaces are smooth, uniform, bright, and free of unwanted materials.
(e)
Use a brush to apply a layer of Alodine 1200 to the open surfaces of aluminum tubes.
S 948-368
(5) Remove burrs from the tube ends:
(a) To remove burrs from the inner bore of the tube ends, use Deutsch plug-type deburring tools or equivalent. Refer to Fig. 804 for the correct deburring procedure.
NOTE: You must remove burrs from the tube inner diameter each
____ time you cut the tube. Make sure the tube shavings do not get into the system.
Do not release the spring pressure of the deburring tool while you pull the tool from the tube.
(b) It is not usually necessary to remove burrs from the tube outer diameter. If it is necessary, use 240-grit abrasive cloth. Use a clean cloth to remove particles.
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(6) Use one of these steps to apply witness marks:
(a)
Use a felt pen or equivalent to apply witness marks as shown in Fig. 829. Use Deutsch tools D12580-1, -2, -3 only or equivalent.
(b)
Make marks directly on the tube to show the minimum insertion depths as shown in Fig. 829. Swage fittings to the marks.
S 378-370
(7)
Apply paint to bare areas. For example, tool marks and areas where you removed paint (fittings and painted tubes).
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(8)
Apply alodine 1200 to open areas of aluminum and BMS 10-11 primer to all other tubes and fittings.
E.
Procedure
(1)
Remove pressure from the systems where you will do the repair.
S 868-372
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(2) Use a union and a tube as shown in Fig. 824.
NOTE: Keep the Permaswage fittings in their container until
____
you are ready to install them.
S 358-374
(3)
Make sure the tube is sufficiently long to do the repair (Fig. 826).
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(4)
Clean the tube as shown in Fig. 828, then cut the tube.
NOTE: Seal the tube ends with a cap if you do not join the tubing
____
immediately.
S 218-376
(5)
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