MACHINE DESIGN 2 (OT TERMS) Flashcards

1
Q

All stresses produced in a belt are __.

A

tensile stresses

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

For a steel pulley of 500 mm in diameter, the recommended number of spokes is –

A

6

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

The centrifugal tension in the belt

A

has no effect on the power transmitted

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

The effective turning force at the circumference of a driven pulley is the ___.

A

net belt pull

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

It is a slight absolute motion of the belt as it passes over the pulleys.

A

Creep of belt

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

In a chain drive system, the __ on the driven shaft will increase as the sprocket ratio increases.

A

Torque

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The speed reduction of a single stage chain drive should not be more than ___.

A

7:1

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

It is the main contributor in the existence of shock load in chain drives.

A

velocity variation

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

What is the pitch of RC 41 chain?

A

12.7 mm

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

It is the term used to describe the occurrence of twist or curl in rope and chain caused by its doubling or bending upon itself.

A

Kinking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

.In order to have smooth operation, the minimum number of teeth on the smaller sprocket, for high speeds, should be

A

21

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

The maximum shear force required for punching depends on __.

A

inversely proportional to their diameters

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

Compared to a v-belt drive, a chain drive _ .

A

is more efficient

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

It is recommended that for a multiple strand V-belt drive, when one of the belt breaks, the whole set of belts should be replaced. Which of the following is the best justification for this?

A

All in the list

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

Which is not a part of the roller chain?

A

center link plate

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

The three basic components of a chain drive are ___.

A

chain, driver sprocket, and driven sprocket

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

The braking torque depends upon ___.

A

all in the list

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

The minimum number of driven pulleys for the simplest compound belt drive is __.

A

2

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

The simplest compound belt drive consists of how many shafts?

A

3

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

Which of the following factor(s) contribute to the effectiveness of the brakes?

A

All of the above

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The maximum shear force required for punching depends on __.

A

sheared area

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

When the torque required by the machine is more than the torque supplied by the motor, the flywheel is ___.

A

retarded

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

Babbit is used as __.

A

all in the list

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

In order to find the maximum bending moment on the arms, it is assumed as a ___.

A

cantilever beam fixed at the hub and carrying a concentrated load at the free end of the rim

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Load acting on bearing in its plane of rotation is called as

A

radial load

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Disc clutch, the clutch disc acts as a ___.

A

Driven member

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

The bearings of heavy series have capacity __ over the medium series.

A

20-30

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Chain drive is intermediate between __.

A

rope and gear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

When the bearing is subjected to large fluctuations of load and heavy impacts, the bearing characteristic number should be ___ the bearing modulus.

A

15 times

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

The bearing characteristic number in a hydrodynamic bearing depends upon

A

viscosity, speed, and bearing pressure

31
Q

In helical gears, the distance parallel to the axis, between similar faces of adjacent teeth, is called

A

axial pitch

32
Q

The flywheel is accelerated when ___.

A

Driving torque > Load torque

33
Q

The ball bearings are provided with a cage __.

A

To maintain the balls at a fixed distance apart

34
Q

The contact ratio for gears is __

A

greater than 1

35
Q

The load carrying ability of a __results when the journal and/or the bearing rotates relative to the load.

A

Wedge film bearing

36
Q

It is the force per unit area required to move a surface at unit velocity, when it is separated by a fluid of unit thickness from a stationary surface.

A

absolute viscosity

37
Q

An advantage of the __ is that the adjustment of center distance of chain drive may be in units of one link instead of a pair of links

A

offset

38
Q

It is the path traced by the point of contact of two teeth from the beginning to the end of engagement.

A

Path of contact

39
Q

It is the depth of a gear tooth space below the pitch line or circle

A

Dedendum

40
Q

The allowable static stress for steel gears is approximately __ of the ultimate tensile stress.

A

one third

41
Q

The size of a gear is usually specified by ___.

A

pitch circle diameter

42
Q

It is the locus of a point on a straight line which rolls, without slipping, on the circumference of a circle, or alternatively the locus of a point on the chord which is held tauted and unwound from a cylinder.

A

Involute

43
Q

The two major categories of bearings used in industry are _.

A

plain and anti-friction

44
Q

If the groove is bigger than rope, there will not be sufficient support for the rope which may, therefore, flatten from its normal circular shape and increase

A

fatigue effects

45
Q

The clearance or amount of movement between the tooth profiles of a pair or train of gears in mesh is called _.

A

Backlash

46
Q

In angular contact bearings, __ bearings are required to take thrust load in both directions.

A

2

47
Q

The value of Lewis form factor used in design of gears is ___.

A

All in the list

48
Q

Which of the following terms does not refer to the arc of contact between the belt and the pulley?

A

Angle of articulation

49
Q

The cross-section of a V-belt is 40 mm wide at the top, 20 mm wide at the bottom and 25 mm deep. Calculate its cross-sectional area.

A

Type C

50
Q

A belt drive is desired to have a center distance between pulleys of approximately 7.5 m. What is the appropriate type of belt to be used for this application?

A

Flat belt only

51
Q

For a flat belt drive, the face of the leather belt in contact with the surface of the pulley is the hair side. Which of the following does not justify this statement?

A

the hair side has higher coefficient of friction

52
Q

When the pulley with a given initial tension starts rotating, the tension in the belt ___.

A

Decreases on the slack side

53
Q

Fiber ropes make contact at _.

A

the sides of the groove of the pulley

54
Q

What is the recommended maximum center distance for twisted belt drive in terms of the width of the belt, b in order to minimize wear and tear of the belt?

A

20b

55
Q

Which of the following belt joints has the lowest joint efficiency?

A

Metal hinged joint

56
Q

The groove angle of the pulley for V-belt drive is usually

A

32° – 38°

57
Q

The following are the advantages in using a cross belt drive except _

A

Opposite pulley rotation

58
Q

The ultimate tensile breaking load (in kN) of cotton ropes in terms of its girth c in mm is approximately _.

A

35.5c^2

59
Q

This type of belt drive makes it possible to change the speed of the driven shaft where the driven pulley is mounted while maintaining the speed of the driving shaft constant.

A

Stepped pulley drive

60
Q

It is recommended that for a multiple strand V-belt drive, when one of the belt breaks, the whole set of belts should be replaced. Which of the following is the best justification for this?

A

All of these

61
Q

The recommended maximum belt speed in ft/s for crossed belt drive is

A

49

62
Q

To loose a chain causes a vibration known as ___.

A

Whipping

63
Q

Which of the following is the most general term?

A

Drum

64
Q

These chains are used for elevating and conveying the materials continuously at a speed up to 2 m/s.

A

Conveyor Chain

65
Q

In this popular wire rope, the wires in the two adjacent strands are twisted in the opposite direction.

A

Composite or Reverse Laid Ropes

66
Q

Larger arc of contact between the chain and the sprocket ensures _.

A

All in the list

67
Q

The useful life of power transmitting chains is usually terminated by _.

A

troubles arising from wear at the joints

68
Q

IWRC, compared to hemp core, is high-temperature resistant, has about _ greater strength and has smaller elongation under load.

A

7.5

69
Q

The power rating of the roller chain is obtained on the basis of what failure criteria?

A

All in the list

70
Q

In a chain drive system, the speed of the driven shaft will decrease as the _ increases

A

Sprocket ratio

71
Q

In roller chain, the bush and the pin form __.

A

Swivel

72
Q

It is a stick slip phenomenon between the pin and the bushing.

A

Galling

73
Q

Which is the most commonly recommended material for medium service for wire rope sheaves?

A

Cast iron

74
Q

Chain drives are recommended to transmit power up to __kW.

A

100