TAPER ROLLER BEARING - F3 4. STABLE (THICK FILM) SLIDING CONTACT BE...
3. Taper roller bearing - f
3
4. Stable (thick film) Sliding contact
bearing - f
4
Which one of the following sequences is correct?
(a)
f
1
< f
2
< f
3
< f
4
(b) f
1
< f
2
< f
4
< f
3
(c)
f
2
< f
1
< f
3
< f
4
(d) f
1
< f
4
< f
2
< f
3
IES-4Ans. (a)
IES-5.
The rating life of a group of apparently identical ball bearings is defined
as the number of revolutions or exceeded before the first evidence of
fatigue crack by:
[IES-2005]
(a) 100% of the bearings of the group (b) 95% of the bearings of the group
(c) 90% of the bearings of the group
(d) 66.66% of the bearings of the group
IES-5Ans. (c)
IES-6.
Match List I (Type of Bearings) with List II (Type of Load) and select the
correct answer using the code given below the Lists:
[IES-2005]
List I
List II
A Deep groove bearing
1. Radial load
B. Tapered roller bearing
2. Radial and axial load
C. Self aligning being
3. Mainly radial load with shaft misalignment
D. Thrust bearing
4. Mainly axial load
A
B
C
D
A
B
C
D
(a) 1
2
3
4
(b)
3
4
1
2
Design of Bearings
S K Mondal’s
Chapter 4
(c) 1
4
3
2
(d)
3
2
1
4
IES-6Ans. (a)
IES-7.
Which one of the following statements is correct?
[IES-2004]
Antifriction bearings are
(a) Sleeve bearings
(b) gas lubricated bearings
(c) Ball and roller bearings
(d) journal bearings
IES-7Ans. (c)
IES-8.
The rolling element bearings are
[IES-2003]
(a) Hydrostatic bearings
(b) Squeeze film bearings
(c) Antifriction bearings
(d) Grease lubrication bearings
IES-8Ans. (c)
IES-9.
A ball-bearing is characterized by basic static capacity = 11000 N and
dynamic capacity = 18000 N. This bearing is subjected to equivalent static
load = 5500 N. The bearing loading ratio and life in million revolutions
respectively are
[IES-2001]
(a) 3.27 and 52.0 (b) 3.27 and 35.0
(c) 2.00 and 10.1
(c) 1.60 and 4.1
Loading ratio
C
IES-9Ans. (b)
18000
3.27
5500
=
P
=
=
Life (million revolutions)
3
3
18000
35
C
⎛ ⎞
=
⎛
⎞
=
=
⎜ ⎟
⎜
⎟
P
⎝ ⎠
⎝
⎠
IES-10. On what does the basic static capacity of a ball bearing depends?
(a) Directly proportional to number of balls in a row and diameter of ball[IES-2009]
(b) Directly proportional to square of ball diameter and inverse of number of rows of
balls
(c) Directly proportional to number of balls in a row and square of diameter of ball
(d) Inversely proportional to square of diameter of ball and directly proportional to
number of balls in a row
IES-10Ans. (c)
IES-11.
Ball bearings are provided with a cage
[IES-1992]
(a) To reduce friction
(b) To maintain the balls at a fixed distance apart
(c) To prevent the lubricant from flowing out
(d) To facilitate slipping of balls
IES-11Ans. (b)
IES-12. In a single row deep groove ball-bearing, cages are needed to [IES-1999]
(a) Separate the two races
(b) Separate the balls from the inner race
(c) Separate the outer race from the balls
(d) Ensure that the balls do not cluster at one point and maintain proper relative
angular positions.
IES-12Ans. (d)
IES-13.
Which one of the following statements is NOT true of rolling contact
bearing?
[IES-1997]
(a) The bearing characteristic number is given by ZN/p where Z is the absolute
viscosity of the lubricant, N is the shaft speed and p is the bearing pressure.
(b) Inner race of a radial ball bearing has an interference fit with the shaft and
rotates along with it
(c) Outer race of the bearing has an interference fit with bearing housing and does
not
rotate
(d) In some cases, the inner race is stationary and outer race rotates
IES-13Ans. (d)
IES-14.
Assertion (A): It is desirable to increase the length of arc over which the oil film
has to be maintained in a journal bearing.
[IES-1996]
Reason (R): The oil pressure becomes negative in the divergent part and the
partial vacuum created will cause air to leak in from the ends of bearing.
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
IES-14Ans. (a)
IES-15.
Consider the following statements about anti-friction bearings: [IES-1994]