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G. When you do repairs, the type of flareless tube sleeves will tell you the installation method to use.
(1)
Use approved power swaging equipment, or roller swaging, to do all swaged-on sleeves and fittings.
(2)
You can preset BACS13AP flareless sleeves by machine. Preset by hand only when a hydraulic or pneumatic-operated presetting tool is not available. If you must preset by hand, we recommend that you preset some samples. Cut the samples into sections longitudinally and make an inspection of the ring cut depth before you preset the part to be repaired.
(3)
You can install the CRYOLIVE sleeve assembly, consisting of CRYOLIVE sleeve, coupling nut and protective cover/inspection tool, by removing the assembly from liquid nitrogen and sliding it on to the tube end. Note that the Size 10, Size 12 and Size 16 coupling nuts used with the CRYOLIVE sleeve are slightly longer than standard MS type coupling nuts and are not interchangeable with MS type coupling nuts.
H.
The H-coupling assembly is a repair coupling which has a union coupling, a slide, and a nut. You can install the H-coupling assembly in straight sections of the tube. Use two end wrenches of applicable size. This assembly is approved for fuel and hydraulic high pressure lines of 21-6-9, titanium 3AL-2.5V, and 304-1/8 hard CRES tubing. The H-coupling assembly is also approved for the repair of 304 CRES annealed and 6061-T6 aluminum tubing lines of 3000 psi or less.
I.
You can use a Cryofit coupling for the inline repair of 3AL-2.5V titanium tubing. To install the Cryofit coupling in a straight tube section, shrink fit the coupling in its position.
J.
You can use the Permaswage coupling for inline repair of 6061-T6 aluminum, 21-6-9 CRES or 304-1/8 hard CRES, and 3AL-2.5V titanium tubing.
K.
You can use the Rynglok union for inline repair of 6061-T6 aluminum, 21-6-9 CRES or 304-1/8 hard CRES, and 3AL-2.5V titanium tubing. Rynglok unions are made of lightweight 6AL-4V titanium alloy and are not to be used in oxygen systems or in fuel cells.
L.
When you repair a section of a tube, correctly align the tube and the fittings. Make sure the fittings touch the bottom at the two ends of the repaired section. Do not use fitting nuts to align the fittings. Fitting nuts used to align fittings during the tube installation will increase the risk of leakage, blowoff, or other failure.
M.
Do a leak check on all hydraulic tubes disconnected during the repair procedure.
(1)
Pressurize the hydraulic tubes for a mimimum of 5 minutes.
(2)
Rub all the fittings with a clean white cloth.
(3)
Look for hydraulic fluid on the cloth to find leakage.
N.
When you remove, install, or do work with hydraulic tube assemblies, obey the guidelines that follow:
(1)
When you remove tubes, make sure the tubes and port fittings have tags that identify the correct connection locations.
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL
(2)
Do not move or change the tube bends. If you move or change the bend in the tube, these bad effects can occur:
(a)
If you move or change a bend in the tube, it can become possible that the tube will align with the incorrect port. If this occurs, incorrect reconnection or cross-connection of the tubes can become possible.
(b)
If you move or change the bend in the tube, it can be possible that the tube will have too much stress when it is connected. Stress can cause cracks in the tubes.
(3)
If you disconnected more than one hydraulic tube and you think there is a possibility you connected the tubes incorrectly or cross-connected the tubes, do an operational check:
NOTE: Use your own judgement to determine if a check is necessary.
____
(a) Do the post-installation test of one or more of the components to which the tubes are connected as a check.
(4) If you disconnected electrical wires to get access to the tubes and you think there is a possibility you connected the wires incorrectly or cross-connected the wires, do an operational check:
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