Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

School > Lubrication > Flashcards

Lubrication Flashcards

1
Q

Name three types of friction.

A
  • Sliding
  • Rolling
  • Fluid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What friction type has tearing and momentary welding of the peaks of the asperities of its two surfaces?

A

Sliding Friction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

From least to most, rate friction type resistance.

A
  • Fluid, Rolling, Sliding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which type of friction is due to material being deformed

A

Rolling Friction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is fluid friction caused by?

A

Electromagnetic bonds between the molecules of fluid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the three main regimes of fluid film lubrication?

A
  • Full Film Lubrication
  • Partial Film Lubrication
  • Boundary Film Lubrication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is Full Film Lubrication?

A

When lubrication is thick enough to completely seperate two surfaces with a continous film.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a Elasto-hydrodynamic Film Lubrication a type of?

A

Full Film Lubrication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is Elasto-hydrodynamic Film Lubrication?

A

When an oil wedge is created under the rolling elements high speed movment but the pressure is so high the two loaded surfaces deform.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Full Film Lubrication depends on what?

A
  • Load Pressure
  • Viscosity of the fluid
  • Minimum speed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Does full film increase while speed increases?

A

Yes but only until a certain point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Label these

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the clearance needed between the bearing and shaft with Full Film lubrication?

A

0.001 inch to operate with no risk of metal to metal contact.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is Viscosity?

A

A measurement of fluid friction (resistance to flow).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Fluids that flow like water have ______ viscosity. Fluids that flow very slowly have ____ viscosity.

A
  • Low
  • High
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is considered to be the most important property of lubrication?

A

Viscosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The higher the viscosity the _____ the load capacity of the film.

A

Higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The higher the viscosity the ______ the flow rate.

A

Slower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The higher the viscosity the _____ the sealing effect.

A

Greater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What factors affect viscosity?

A
  • Temperature
  • Pressure
  • Speed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

As Temperature increases, Viscosity ________.

A

Decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Viscosity _________ with large increases of pressure.

A

Increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the units of Viscosity?

A
  • Centistroke
  • SUS (SSU)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does SUS stand for?

A

Saybolt Universal Seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is Pour Point? How is determined?
The lowest temperature at which an oil is observed to flow. It is three degrees Celsius above the temperature at which the oil shows no movement from a container held horizontally for 5 seconds.
26
What is Viscosity Index?
A number given that identifies the amount of change in the viscosity of a lubricant over a temperature range.
27
Very little change in viscosity as it is heated from 40 to 100 Celsius would have a ____ viscosity index.
High
28
Why is Viscosity Index important?
It tells you how stable a lubricant is over a range of operating temperatures.
29
What does pour point depend on?
It depends on the formation of wax crystals in paraffin-based oils, while in naphtha-based oils it depends on the increase in viscosity at low temperatures.
30
Can two oils have the same pour point but different viscosities?
Yes
31
What is Flash Point?
Is the lowest temperature at which the vapour above an oil ignites when a flame is passed over it.
32
What organization has developed a viscosity grading system for engine oils and a seperate system for manual tranmission oils?
SAE (Society of Automotive Engineers)
33
What are Low-temperature Engine Oil Grades indicated with? The lower the number in the grade means what?
- W Ex: 20W - The lower the minimum temp it can handle.
34
What must you be careful about with Low-temp Engine Oil Grades?
The oil may be too thin for use during the summer.
35
High-Temperature Engine Oil Grade notation is different how?
There is no W in the notation.
36
What is the difference with Multigrade Engine Oils and usual Low-Temp and High-Temp engine oils?
- Multigrade Engine Oils have Viscosity Index improvers added to them Ex: 10W-30 is an oil that functions like a 10W oil at -30C and maintains its film strength of a 30 oil at 100C
37
Are SAE Engine Oils and Industrial Oil based on the same grade critiera?
No! Industrial Oils and SAE Engine Oil grades may not be the same in viscosity.
38
What are Petroleum-based Oils dervied from?
The base stock produced at the refineries.
39
What are two types of crude oil base stocks?
Paraffin and Naphtha
40
Which oil’s viscosity is least affected by weather, Paraffin or Naphtha?
Paraffin-based oils
41
What kind of weather is Synthetic Oil used in?
Extreme cold and extreme heat
42
Do additives in oil wear out?
Yes
43
What is the percentage of oil additives in oil usually?
22%
44
What are Oxidation Inhitors also called?
Antioxidants
45
What is the purpose of detergent additives in oil?
Clean the surface of the components.
46
Answer
C)
47
Answer
C)
48
Answer
D)
49
Answer
C)
50
Answer
D)
51
Answer
C)
52
Answer
D)
53
Answer
B)
54
Answer
C)
55
Answer
A)
56
Answer
D)
57
Answer
B)
58
Answer
D)
59
Answer
B)
60
Answer
A)
61
Answer
B)
62
Answer
D)
63
Answer
D)
64
Answer
D)
65
Answer
D)
66
Answer
A)
67
Answer
A)
68
Answer
A)
69
Answer
B)
70
Answer
A)
71
Answer
C)
72
Answer
A)
73
Answer
D)
74
Answer
B)
75
Answer
C)
76
Answer
C)
77
Answer
A)
78
Answer
A)

School (46 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions