Fluid Lines and Fittings AMP Generals

Metal tubing fluid lines are sized by wall thickness and

• outside diameter in 1/16 inch increments.

• inside diameter in 1/16 inch increments.

• outside diameter in 1/32 inch increments.

Rolling-type flaring tools are used to flare X, X, and X tubing.

• Stainless steel, hard copper, mild steel.

• Titanium, soft copper, corrosion resistant steel.

• Soft copper, aluminum, brass.

he maximum distance between end fittings to which a straight hose assembly is to be connected is 50 inches. The minimum hose length to make such a connection should be

• 54-1/2 inches.

• 51-1/2 inches.

• 52-1/2 inches.

What is the color of an AN steel flared-tube fitting?

• Black.

• Blue.

• Red.

A scratch or nick in aluminum tubing can be repaired provided it does not

• appear in the heel of a bend.

• appear on the inside of a bend.

• exceed 10 percent of the tube OD on a straight section.

From the following sequences of steps, indicate the proper order you would use to make a single flare on a piece of tubing:
1. Place the tube in the proper size hole in the flaring block.
2. Project the end of the tube slightly from the top of the flaring tool, about the thickness of a dime.
3. Slip the fitting nut and sleeve on the tube.
4. Strike the plunger several light blows with a lightweight hammer or mallet and turn the plunger one-half turn after each blow.
5. Tighten the clamp bar securely to prevent slippage.
6. Center the plunger or flaring pin over the tube.

• 1, 3, 5, 2, 4, and 6.

• 3, 1, 6, 2, 5, and 4.

• 3, 1, 2, 6, 5, and 4.

When flaring aluminum tubing for use with AN fittings, the flare angle must be

• 37°

• 39°

• 45°

Excessive stress on fluid or pneumatic metal tubing caused by expansion and contraction due to temperature changes can best be avoided by

• using tubing of the same material as the majority of the adjoining structure.

• using short, straight sections of tubing between fixed parts of the aircraft.

• providing bends in the tubing.

When a Teflon hose has been in service for a time, what condition may have occurred and/or what precaution should be taken when it is temporarily removed from the aircraft?

• The hose interior must be kept wet with the fluid carried to prevent embrittlement/deterioration.

• The hose may become stiff and brittle if not flexed or moved regularly.

• The hose may have developed a set, or have been manufactured with a pre-set shape, and must be supported to maintain its shape.

Which of the following statements is/are correct in reference to flare fittings?
1. AN fittings have an identifying shoulder between the end of the threads and the flare cone.
2. AC and AN fittings are considered identical except for material composition and identifying colors.
3. AN fittings are generally interchangeable with AC fittings of compatible material composition.

• 1

• 1 and 3

• 1, 2, and 3