Fluid Lines and Fittings

Question 1

The size of rigid tubing is determined by

Answer 1

Outside diameter

Question 2

The outside diameter of rigid tubing is in increments of

Answer 2

1/16th of an inch

Question 3

A -4 “B” nut has an outside diameter of:

Answer 3

4/16’’

Question 4

A -10 “B” nut has an outside diameter of:

Answer 4

10/16’’

Question 5

The two sizing considerations for rigid tubing are:

Answer 5

1. Outside diameter

2. Wall thickness

Question 6

Rigid tubing wall thickness is given in increments of:

Answer 6

thousandths of an inch

Question 7

The method of finding the inside diameter of rigid tubing is to:

Answer 7

Subtracting twice the wall thickness from the outside diameter

Question 8

When cutting a new piece of rigid tubing, you should ALWAYS cut it approximately ______ % (shorter or longer) than the tube being replaced.

Answer 8

10% longer

Question 9

Why should the rigid tubing replacement be cut 10% longer than original?

Answer 9

To allow for margin of error for bending

Question 10

What is the preferred method for rigid tube cutting?

Answer 10

circular tube cutter

Question 11

To start cutting a rigid tube, mark the tube with

Answer 11

a felt tip maker

Question 12

The finishing two steps in cutting a rigid tube with a circular tube cutter

Answer 12

1. Deburr

2. Blow out with compressed air to remove chips

Question 13

When bending lines for a repair, with complex curves and bends, you must produce bends that are ____% of

Answer 13

75% of the original tube diamter

Question 14

What are the 3 types of rigid tube connections?

Answer 14

1. Single/ Double flared connectors
2. Flareless connectors
3. Hose/clamps over a beaded tube

Question 15

The type of fittings/ connectors used for fluid lines depends on 3 things:

Answer 15

1. Pressure range
2. Material being used
3. Routing

Question 16

A flared tube fitting consist of what 2 parts?

Answer 16

1. B-nut

2. Sleeve

Question 17

What is the advantage to using a B-nut and sleeve?

Answer 17

Protects the flare from damage as the nut is tightened

Question 18

Two differences between AC and AN flared tube fittings

Answer 18

1. AN fitting has a shoulder between the threads and cone, AC does not
2. AN is longer for the same size

Question 19

Color of AN flared tube fitting

Answer 19

Blue or Black

Question 20

Color of AC flared tube fitting

Answer 20

Gray or yellow

Question 21

Angle of the AC and AN flared tube fittings

Answer 21

35 degrees and 37 degrees respectively

Question 22

Blue AN flared tube is made of:

Answer 22

Aluminium

Question 23

Black AN flared tube fitting is made of:

Answer 23

Steel

Question 24

The step necessary prior to installing a flareless fitting is called:

Answer 24

Presetting

Question 25

What is presetting?

Answer 25

Applying enough pressure to the sleeve to cause it to cut into the outside of the tube

Question 26

Before beading, what should you do to the part of the tube that is ready to be beaded?

Answer 26

Lubricate with oil

Question 27

Fuel lines should be secured via

Answer 27

bonded line support clamps

Question 28

Scratches or nicks in aluminium tubing are repairable as long as they are

Answer 28

no deeper than 10% of wall thickness and not in the heel of the bend

Question 29

Dents in aluminium tubing are serviceable as long as they are

Answer 29

less than 20% of the tube diameter and not in the heel of the bend

Question 30

Lines that carry fuel are labeled :

Answer 30

FLAM

Question 31

Lines that carry generally dangerous fluids are labeled:

Answer 31

PHDAN

Question 32

Why would you use a bullet or a slug for a rigid tube?

Answer 32

To repair a small dent

Question 33

The 4 materials used for construction of the inner liner of flexible tubes:

Answer 33

1. Buna-N 2. Neoprene 3. Butyl 4. Teflon

Question 34

Which material is most suitable for the use of Skydrol?

Answer 34

Butyl

Question 35

What is important with in regards to servicing teflon hoses

Answer 35

Teflon "takes a set" and becomes rigid, So DON"T bend it when you remove it

Question 36

The laylines are typically which 3 colors?

Answer 36

1. red 2. white 3. yellow

Question 37

Medium pressure hoses are used for pressure up to:

Answer 37

3000 psi

Question 38

The size of flexible lines is determined by:

Answer 38

inner diameter

Question 39

The inner diameter of a flexible line is given in increments of:

Answer 39

1/16''

Question 40

Flexible lines must have between ____ and ____ slack to allow for

Answer 40

5-8% slack to allow for dimensional changes

Question 41

The final step in a flexible hose fabrication is to:

Answer 41

clean the new hose assembly