Pipes And Unions

Question 1

How are flexible hoses categorised?

Answer 1

By maximum pressure

Question 2

What are the rigid pipes on gas turbine engines made from?

Answer 2

Stainless steel

Question 3

How would you test a hydraulic hose?

Answer 3

Pressure test 1.5 * working pressure

Question 4

To prevent damage to seals on fitment you would

Answer 4

Use a cardboard protector over e threaded portions

Question 5

Flexible lines are identified by

Answer 5

Material

Question 6

A pipe carrying lubricant would be identified by the colour

Answer 6

Yellow

Question 7

Which material is a hydraulic fluid hose made from?

Answer 7

Teflon

Question 8

Hydraulic pipes are made from

Answer 8

Annealed steel

Question 9

The continuous coloured line on a hose assembly

Answer 9

Will assist in detection of any twist in an installed hose

Question 10

When fitting a replacement flexible hose

Answer 10

Ensure adequate clearance between the hose and the aircraft structure

Question 11

MIL-H-5606 hydraulic fluid O-rings are identified with a

Answer 11

Blue dot

Question 12

A metal pipe has a small indentation. What are the limits?

Answer 12

No dent on a bend

Question 13

An aircraft pipe has a number stamped on it. It is the

Answer 13

Serial number

Question 14

The length of a straight hose assembly is measured

Answer 14

Between the extremities of the two nipples

Question 15

Metal tubing fluid lines are sized by wall thickness and

Answer 15

Outside diameter and 1/16 inch increments

Question 16

A certain amount of slack must be left in a flexible hose during installation because, when under pressure it

Answer 16

Contracts in length and expands in diameter

Question 17

The term ‘cold flow’ is generally associated with

Answer 17

Rubber hose

Question 18

Flexible lines must be fitted with a slack

Answer 18

Of 5-8% of the length

Question 19

The material specifications for a certain aircraft require that a replacement oil line be fabricated from 3/4 inch, 0.072 5052-0 aluminium alloy tubing. What is the inside dimension of this tubing?

Answer 19

0.606 inch

Question 20

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

Answer 20

Using short, straight sections of tubing between fixed parts or the structure of the aircraft
OR
Providing bends in the tubing

Question 21

Flexible hose used in aircraft systems is classified in size according to the

Answer 21

Inside diameter

Question 22

Which tubing have the characteristics (high strength, abrasion resistance) necessary for the use in a high pressure (3,000 PSI) hydraulic system for operation of landing gear and flaps?

Answer 22

Corrosion resistant steel annealed 1/4H

Question 23

A gas or fluid line marked with the letters PHDAN

Answer 23

Is carrying a substance which may be dangerous to personnel

Question 24

A 3/8 inch aircraft high pressure flexible hose compared to a 3/8 inch metal tubing used in the same system will

Answer 24

Have equivalent flow characteristics

Question 25

How do you assemble a banjo hose?

Answer 25

Put washer either side of the banjo

Question 26

To install a flareless coupling

Answer 26

Turn until torque is felt plus 2 flats

Question 27

In most aircraft hydraulic systems, two-piece tube connectors consisting of a sleeve and a nut used when a tubing flare is required. The use of this type of connector eliminates

Answer 27

The possibility of reducing the flare thickness by wiping or ironing during the tightening process

Question 28

Adaptor nipples are not required on

Answer 28

Pipe to externally coned adaptor

Question 29

A butyl rubber seal is made from

Answer 29

Synthetic rubber

Question 30

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

Answer 30

Black

Question 31

Which statement about military standard (MS) fitting is correct?

Answer 31

MS flareless fittings must be tightened to a specific torque OR During installation MS flareless fittings are normally tightened by turning the nut a specified amount after the sleeve and fitting sealing surface have made contact, rather than being torqued

Question 32

A flexible sealing element subject to motion is a

Answer 32

Packing

Question 33

When replacing a hydraulic pipe, where would you find the correct replacement part?

Answer 33

Parts catalogue