Fasteners Flashcards
1
Q
What is a right hand thread
A
A thread cut in a clockwise direction most screws are right hand
2
Q
What is left hand thread
A
A screw cut in the anti clockwise direction
3
Q
What is the lead
A
Distance moved in one complete revolution
4
Q
What is the form
A
The shape of one complete contour
5
Q
What is the crest
A
The prominent point in the thread
6
Q
What is the root
A
The bottom point in the thread grove
7
Q
What is the flank
A
The slope of the thread between the roots and crest
8
Q
What is the thread angle
A
Angle between 2 adjacent flanks
9
Q
What is the major diameter
A
On male crest to crest
Female root to root
10
Q
What is the minor diameter
A
Male root to root
Female crest to crest
11
Q
What is the pitch
A
The distance of crest to crest on the same pitch
12
Q
What is the run out
A
There the thread begans to Become straight
13
Q
What is the depth
A
Radial distance between the food and the crest
14
Q
What is a single start
A
Lead = pitch
In one resolution the distance travel so one crest to crest
15
Q
What is a 2 start
A
Lead = 2x pitch
16
Q
What is BS
A
British standards
17
Q
What is BA
A
British association
18
Q
What is AN
A
American national
19
Q
What is a BSW
A
British standards whitworth
For general purpose
Angle of 55
20
Q
What is BSF
A
British standard fine
Finner version of BSW has more threads and less diameter
Has resistance to vibration
55 angle
21
Q
What is a BSP
A
British standard pipe Fine pitch Used for pipeline couplings Strong connection Can be tapered to make a pressure tight joint 55 angle
22
Q
What is BA
A
British association
47.5 angle
Only in sizes 1/4 inch
Use for smaller mechanical or electrical parts
Range from sizes 0 to 10 the smaller the number the higher the thread
23
Q
What is ANC and ANF
A
American national coarse and fine
60 angle
24
Q
What is a UF
A
Unified thread ID by machines symbol and mark 60 angle UNC – Unified National Coarse • UNF – Unified National Fine • UNEF – Unified National Extra Fine
25
What is TPI
Thread per inch
26
What is a deeper thread
Less threads per inch
27
What is the distance between course and fine pitch
A coarse pitch thread has a greater lead than a fine pitch thread of the same major diameter
28
What is a buttress thread
Can only transmit power in one direction
29
What is the thread depth that should be showing
1/32 inch
| 0.8mm
30
What material is a boot with a cross on
Steel
31
What material is a bolt with a line on
Crosion resistant steel
32
What material is a bolt with 2 dashes
Aluminium
33
What is U in a part number
Unplated
34
What is a - on a bolt identification
Plated
35
What is D on a bolt identification
Drilled shank
36
What is H on a bolt identification
Drilled head
37
What is single number on a bolt identification
Grip length , measured in 16th
38
What is X on a bolt identification
1/64inch oversized
39
What is Y on a bolt identification
1/32 inch oversized
40
What is NE on a bolt identification
Long threaded
| Boeing only
41
What is NF on a bolt identification
Short threaded
| Boeing only
42
What do material less than 2.4mm
No threads inside hole
43
What do materials with greater than 2.4 mm have
Two threads inside the hole
44
What is the max number of washes used
3
45
What is the grip length of a bolt be equal to
The material thickness
46
What are the 4 types of studs
Standard
Waisted
Stepped
Shouldered
47
What is a stud
A price is rod with a thread at each end and with a plain portion in the middle
48
Why is stranded stud used
Most widely used
| Same diameter
49
What is a waisted stud
Same strength
| Saves weight
50
What is a stepped stud
Provide a strong Anchorage
| Used for soft material
51
What is shouldered stud
Maximum rigidity is required against the lateral strength
52
What is a stud box
Used to fit a stud
Screwed at one end
Used into price
Stud removed
53
What is an stud insertion or removal tool
Insertied into thread by hand
Inserting tool places over the protruding end
Locked together
54
What is a lock nut
Screwed into outer frame of the stud and locked firmly together
Screwed into housing
55
What is filed flat
Removal of damaged studs
| Only if surface is protruding
56
What is ezi-out
When a stud is broken below the surface
Drill hole in stud
Remove using a ezi-out tool
57
What is structural screw
Used for assembly
Made of alloy steel
Are Heat treated
Same strength as bolts , only have different heads
58
What is flush head
Flush-head machine screws are used in countersunk holes where a flush finish is desired. These screws are available in 82 and 100 degrees of head angle and have various types of recesses and slots for driving.
59
What is round head
Round-head machine screws are frequently used to assemble highly stressed aircraft components.
60
What is fillister head
Fillister-head machine screws are used as general-purpose screws. They may also be used as cap screws in light applications, such as the attachment of cast aluminium gearbox cover plates.
61
What is socket head
Socket-head machine screws are designed to be screwed into tapped holes by internal wrenching. They are used in applications that require high-strength precision products, compactness of the assembled parts, or sinking of the head into holes.
62
What is a self tapping screw
cuts its own internal threads as it is turned into the hole. Self-tapping screws can be used only in comparatively soft metals and materials.
63
What is a machine self tapping screw
Used for removable parts
Nameplates castings
Hole needs to be pre drilled
64
What is sheet metal slef tapping screws
Temporary attaching sheet metal for riveting
65
What is a non slef locking nut
These are used with drilled-shank hex-head bolts, clevis bolts, eye bolts or struts and are designed to accommodate a cotter pin or wire locking as a means of safetying.
66
What is a shear castle nut
Used only for shear load on clevis bolts.
| These nuts are available in cadmium-plated nickel steel, corrosion-resistant steel and in 2024 aluminium alloy.
67
What is a castle nut
These nuts are designed to fit on standard airframe bolts and may be used when the bolt is subjected to either shear or tensile loads. They are made from the same material as the shear castle nut.
68
What is a slotted engine nut
This nut is designed for use on an aircraft engine and is not approved for airframe use. It is made of heat-treated steel.
69
What is a wing nut
Wing nuts are intended for use on hose clamps and battery connections, etc., where the desired tightness is ordinarily obtained by the use of fingers. They are made of either cadmium-plated steel or brass.
70
What is a locking nut
A lock nut is a thin, plain nut which is tightened down firmly onto the main, plain nut. This friction wedges the threads to prevent them both slackening.
71
What is a nylon stiffnuts
This nut has an unthreaded nylon insert permanently housed at the outer end. As the bolt threads engage the insert, the nylon is compressed into them, setting up a friction which prevents the nut unscrewing. Low temperature use only.
72
What is a oddie stiffnut
Oddie stiffnuts have six tongues at their outer end which are bent inwards
to form a circle slightly less in diameter than the root of the bolt thread. As the bolt passes through the nut, the tongues are pushed upwards, applying a locking load onto the bolt thread.
73
What is a Aerotight and Philidas Stiffnuts
These nuts have slotted locking extensions which are closed during manufacture to put the screw-thread out of alignment. As the bolt engages and realigns the extension thread, a grip is produced which provides a friction lock.
74
What is a anchor nut
A floating type anchor nut is used when a slight range of movement is necessary to ensure the bolt can locate
75
What is High-Temperature Self-Locking Nuts
Above 120 degrees
All metal locknuts
Made is steel CRES
Not in contact with aluminium
76
What is Low-Temperature Self-Locking Nuts
Temps under 121 degree
| Fibre or nylon
77
What is a heli coil inset
Protect soft metal casing
Available for all thread types
Tang and notch
78
What is C
CRES
79
What is F
Carbon steel
80
What is N
Ni cr fe alloy
81
What is wire locking
Double twist
| 3 inch max gap
82
What is a spring washer
This is either a single coil or square section spring with sharp corners or
a double-coil spring. It is fitted beneath the nut so that when the nut is tightened the spring is compressed, setting up a friction and thus preventing the nut from vibrating loose.
83
What is a tab washer
Plain nuts
| One tab is ment against the other over edge is component
84
What is difference between transition thread and normal thread
Normal threads have a symmetrical V shape
85
What does a triangle mean on a bolt head
Close tolerance
86
Can you used a slotted nut in air frame
No
87
When can you re use nyloc stiffnuts
If you can finger tighten cant used it
88
What direction do aerotight stuff nuts go in
Vertical
89
What is a heli coil fitter
Supplied by manufacturer
Straight fluted for hand tapping
Sprial for machine tapping
90
What is the depth of a heli coil
Half a thread down
91
What is safetying
Securing all air craft nuts and bolts so don’t come use
92
What is single locking sure used
In small parts
93
What is a shakeproof washer
If it still has sharp teeth can be re used
| The teeth grip into nuts
94
What safteying devices cant be reused
```
Lock nuts
nylon threaded
Split pins
Wire locking
Tab washers
```
95
2 types of pip pin
Ring pool
| Double acting
96
What is the difference between the 2 types of dzus
Heavy type has a grommet light weight doesn’t
97
What is light duty type dzus fasteners used for
Box covers
| Access hole lightweight fairing
98
What is heavy duty type dzus used for
Cowlings
| Heavy fairing
99
What are split pins used for
Secure bolts screws nuts and pins
100
What materials are split pins made of
Low carbon steel
| Stainless steel
101
What split pin materials are used in non-magnetic need
Stainless steel cotter pins
102
What is A rivet
1100 aluminium alloy
No mark
No heat treat
103
What is 2117 rivet
Aluminium alloy
Code AD
Flat dimple
No heat treat
104
What is 2017 rivet
Aluminium alloy
Code D
Heat treat above 3/16 diameter
Raised dot
105
What is a DD alloy
2024 aluminium alloy
Raised double dash
Solution heat treated
106
What is 7050 rivet
Aluminium alloy
Code E
Raised ring
107
What is B rivet
5056 aluminium alloy
| Raised cross
108
What is F rivet
Corrosion resistant steel
| No mark
109
What is Monel rivet
Symbol M
| 2 dimples or R symbol
110
What is T rivet
Titanium
| Raised V or T
111
What is 426 on a rivet
100 degrees counter sunk head
112
What is 470 on a rivet
University head
113
What are the types of High lock fasteners
A threaded pin with a head (universalorcountersink)
| A collar with an internal thread and an external shear groove
114
What is a special fasteners
With a close tolerance
115
What are the types of fit
Clarence - rivet smaller than hole
Transition
Interference - rivet bigger than hole - tight to get in
116
Aluminium alloys what sort of fit do hi-locks have
Interference
117
How to insert hi-lock
Allan key holds pin
| Hex drive turns collar
118
What is important in hi lok
The collar is the right size
And right way round
Has to sit on parallel surface
119
What is the maximum out of parallel surfed for a aluminium collar
3 degrees
120
What is the maximum out of parallel degrees for a CRES collar
0.5 degrees
121
How to insert hi-lok fasteners
Check grip length
Pins and colar match up
Lubricate if required
Install my hand or power
122
What is the difference between hi-lok and hi-lite
Hi-lite has less material , as less run out , up to 15% lighter , it is weight saving
123
What is a red collar
Material 2024
| 1/64 oversizes
124
What is a blue colar
Material 2024
| 1/32 oversized
125
What is the difference between red and blue colour
The sizes of the diameter oversizes
126
What is a black collar
Material 2024
| 3/64 oversized
127
When you fit a taper lok
The same way as any bolt
128
why are taper lok used
Distribution of stress
| Used in high fatigue areas
129
What is the ratio of a taper bolt
1:48
130
How to taper lok Come from supplier
With a special lubrications
131
How to ensure a high precision hole
Reaming
| Drill and clamp parts
132
Who can fit taper lok
Only approved operators
| Skilled people
133
Why used hi-lok hi-lite
Gets a much better seal
| Used for fuel tanks
134
When are lockbolts used
Tension and sheer leadings
135
What are the pieces of a lock bolt
Pin and collar
136
What are the properties of a pin and collar
Strong and light
137
Can lockbolts be used in non parallel surfaces
Yes
138
What is the maximum out of parallel degree for CRES in a lockbolt
7 degrees
139
What is the maximum out of parallel degrees of a titanium lockbolt collar in tension stress
5
140
What is the maximum out of parallel degrees of a titanium lockbolt collar in shear stress
3
141
What are the 3 types of cherrylock
Standard
Bulbed
oversizes
142
What are the 3 parts of a cherrylock blind rivet
Body
Pin
Lock-collar
143
What are the 2 types 0f Cherrymax rivet
Cherrymax
| Oversized cherrymax
144
What are they 3 parts of a cherrymax
Body
Pin
Locking collar
145
What is the difference between a cherrymax and a cherrylock
Can used any tool to insert a cherrymax
| Need specialist tool for cherrylock
146
Properties of Olympic lock rivet
Light 3 piece mechanical locked rivet
147
What shouldn’t you do on a Olympic-lok rivet
Never file stem off after it’s cu
| Will weaken full rivet
148
What tools should you use on Olympic lok
Specialist
149
What is a rivnut
Rivet and nut combo
150
What is a oddie stiffnut
Have six tongues
Bent inward to form a circle
As the bolt passes through the tongues are pushed upward applying a locking load into bolt thread
151
When is a anchor nut used
When a slight range of movement is necessary to ensure the bolt can locate
152
What is a strip nut
Used when a row of anchor nuts is required
| Fitted at equal intervals
153
What are High-Temperature Self-Locking Nuts made of
Steel alloy
CRES
Silver plated
154
What are Low-Temperature Self-Locking Nuts
Fibre or nylon
155
What are helo-coil use for
Soft metals l
156
What is the twists per inch of locking wire
AMM chapter 20
157
What is a spring washer
Fitted beneath the nut so that when the nut is tightened the spring is compressed, setting up a friction and thus preventing the nut from vibrating loose.
158
What is the tab washer
Metal washer with 2 or more tabs
| Cannot be removed
159
What is a shake proof washer
Has sharp edges sticking out
| Can be tightened and go over sharo edges but can’t go reverse order
160
What are locking plates used
Instead of tab washer where repeated removal of bolt is required
161
What is a pip pin
Simple and secure
Non threaded fastener
Allows the rapid installation and removal of parts without tooling
162
What is a ring pull detent pin
A single ball locates the pin, no positive lock
Push to insert
Pull to remove
163
What is a grommet
sheet metal ring held in the access panel by the retaining ring.
164
What are the types of grommets
Flush and protruding
165
What is a stud assembly consists of
* Stud
* Cross pin
* Spring
* Spring cup
166
What type of Dzus fasteners have a grommet
Heavy duty
167
What are the 2 types of airloc
Fixed type
| Floating type
168
What is a airloc made of
Receptacle
Stud
Cross pin
169
What is a floating type airloc used
Makes for easier alignment of the stud in the receptacle
170
What is a cotter pin used for
used to secure bolts, screws, nuts and pins.
171
What are cotter pins
low-carbon steel, while others consist of stainless steel, and thus are more resistant to corrosion.
172
What are stainless steel cotter pins used for
Where non magnetic material is required
173
What is a hollow saddle key
Hollowed to fit the radius of the shaft
I driven into the position
Transmit a moderate load
No keyway cut into shaft so can’t have heavy load
174
What is a flat saddle key
This rectangular or square-section key is driven into a keyway in the hub and bears upon a flat on the shaft. It provides a more positive drive than that achieved by the hollow saddle key.
175
What is a gib headed key
Tapered key
Must be perfectly aligned
Can carry a great load
176
What is a feather key
When axial movement is required
| Used in geat box
177
What is a woodruff key
Capital D
| Suitable for parallel or taper shafts
178
What is a rule of thump for choosing a rivet
choose a rivet whose diameter is at least 3 times the thickness of the thickest sheet being joined
179
How to measure length of countersunk head
From the very top to the bottem
180
How to measure length of a universal head
The length of shaft
181
What is a AN 430
Round head
182
What is AN 456
Brazier head
183
What are the 3 Olympic loc head
* Universal (protruding)
* 100° flush countersunk
* 100° flush shear
