Maintenance Practices M7.15A

Question 1

What is capillary action

Answer 1

The process in which the solder flows between 2 surfaces

Question 2

What is high temp solder

Answer 2

Tin Antimony lead solder

Question 3

Up to what % antimony increases solder strength

Answer 3

6%

Question 4

What is the most common non corrosive flux

Answer 4

Rosin

Question 5

Sulphur embrittlement

Answer 5

Cannot restore

Question 6

What is the cylinder colour for acetalyne

Answer 6

Maroon

Question 7

What is pure acetalyne dissolved in

Answer 7

Acetone and pressurised to 15 bar

Question 8

Why are acetalyne bottles kept upright

Answer 8

Because acetalyne is very unstable

Question 9

What pressure must acetalyne not exceed when being used as a fuel

Answer 9

15 psi

Question 10

At what pressure will acetalyne explode

Answer 10

29.4psi

Question 11

Check valves on acetalyne bottles are only to prevent return of flow what is used as a flashback arrestor

Answer 11

Flashback arrestors

Question 12

What are the two different types of oxy acetalyne torches

Answer 12

• Equal pressure
• Injector type

Question 13

Why is equal pressure Better than the injector type

Answer 13

More stable and safe. Less susceptible to flashback

Question 14

What is fusion welding

Answer 14

Electrically bonding 2 pieces together

Question 15

What is a class A fusion weld

Answer 15

A vital joint (Failure would jeopardise the aircraft safety)

Question 16

What is a Class B1 Fusion weld

Answer 16

A secondary structure (Failure would not jeopardise the aircraft safety)

Question 17

What is a Class B2 fusion weld

Answer 17

Non structural

Question 18

Is the TIG electrode consumed or not consumed during the welding process

Answer 18

Not consumed

Question 19

What does TIG stand for

Answer 19

Tungsten Inert Gas

Question 20

What gas does TIG use

Answer 20

Argon

Question 21

Why do you not need to use a flux with TIG welding

Answer 21

Argon gas is used which is an inert gas

Question 22

What current can be used with TIG welding

Answer 22

AC or DC current

Question 23

The gas metal arc and gas tungsten arc welding processes are known as what

Answer 23

Gas shielded arc process

Question 24

Which welding process electrode doubles as the weld feed and is consumed

Answer 24

MIG

Question 25

During the MIG process what helps stop the surface from oxidising

Answer 25

Inert gas and shielding process

Question 26

How to inspect a weld to see if it’s of good quality

Answer 26

• Visual check
• Uniform in width
• No burn marks
• No oxide present

Question 27

What is Porosity

Answer 27

When gas is trapped in a weld

Question 28

What is the best way to detect porosity in a weld

Answer 28

X ray

Question 29

What is used during the brazing process

Answer 29

Bonding 2 pieces of metal with zinc/copper alloy filler

Question 30

Is brazing high temp or low temp

Answer 30

Low temp

Question 31

What adhesive relies on atmosphere

Answer 31

Contact adhesive

Question 32

What does bonding rely on to be strong and of good quality

Answer 32

Adhesion and cohesion

Question 33

Which must be stronger adhesion or cohesion

Answer 33

Adhesion

Question 34

What is wetting

Answer 34

Making sure there is a good surface for bonding

Question 35

What is capillary action

Answer 35

When two materials are together the binding agent will fill the narrow gaps to perform the bond

Question 36

Bond line thickness must not be greater than what

Answer 36

0.1mm