PIPES AND HOSES

Question 1

TUBING SIZES
Metal tubing is sized by outside diameter (o.d.), which is measured fractionally in ______.

Answer 1

sixteenths of an inch

Question 2

The wall thickness is typically printed on the tubing in ______.

Answer 2

thousands of an inch

Question 3

The objective in tube bending is to obtain a smooth bend without flattening the tube. Tubing _____ diameter usually can be bent without the use of a bending tool.

Answer 3

under 1/4” in

Question 4

The flaring tool used for aircraft tubing has male and female dies ground to produce a flare of __1____. Under no circumstance is it permissible to use an automotive-type flaring tool which produces a flare of ___2____.

Answer 4

1. 35° to 37°
2. 45°

Question 5

Minor dents and scratches in tubing may be repaired.
Scratches or nicks not deeper than _____ in aluminum alloy tubing, which are not in the heel of a bend, may be repaired by burnishing with hand tools.

Answer 5

10 percent of the wall thickness

Question 6

Aluminum 6061-T6, corrosion resistant steel 304- l/8h and Titanium 3AL-2.5V tubing can be repaired by ____.

Answer 6

swaged fittings

Question 7

When a flexible hose has been repaired or overhauled using existing hardware and new hose material, and before the hose is installed on the aircraft, it is recommended that the hose be tested to at least ______.

Answer 7

1.5 system pressure

Question 8

When installing flexible hose, provide slack or bend in the hose line from _____ of its total length to provide for changes in length that will occur when pressure is applied.

Answer 8

5 to 8 percent

Question 9

When available, use the hose clamp torque-limiting wrench. These wrenches are available in calibrations of _______ limits.

Answer 9

15 and 25 in-lb

Question 10

In the absence of torque limiting wrenches, follow the _________.

Answer 10

finger-tight-plus-turns method