LIMIT AND FITS MCQ
1) When tolerance is given on one side of the basic dimension, it is called
Toierance system
Allowance system
Unilateral tolerance
Bilateral tolerance
Correct answer- (C)
2) Limits of 50 mm hole is ES = + 0.025 and El = + 0.002 mm. The maximum and minimum hole sizes will be :
Max. 50.02 mm; Min. 49.998 mm H7
Max. 50.025 mm; Min. 50.002 mm
Max. 49.998 mm; Min. 50.002 mm
Max. 49.990 mm; Min. 49.975 mm
Correct answer- (B)
3) British standard limit system consists of
21 classes of fits and 16 grades of tolerances
12 classes of fits and 61 grades of tolerances
16 classes of fits and 21 grades of tolerances
61 classes of fits and 12 grades of tolerances
Correct answer- (A)
4) A dimension is stated as 25 ±0.02 mm in a drawing. What is the tolerance?
25.00 mm
+ 0.02 mm
—0.02 mm
0.04 mm
Correct answer- (D)
5) The difference between the maximum and minimum sizes allowed in manufactured components is called :
Clearance
Allowance
Tolerance
Limit
Correct answer- (C)
6) The measured size of the dimension of a component is called
Basic size
Nominal size
Allowed size
Actual size
Correct answer- (D)
7) A pin is fitted in a hole. The tolerance zone of the pin is entirely above that of hole. The fit obtained will be
Clearance fit
Transition fit
Interference fit
None of the above
Correct answer- (C)
8) Interchangeability is normally applied for
Repairing of parts
Mass production
Single piece production
All the above
Correct answer- (B)
9) Bilateral tolerance is fixed
On upper side of the basic size
On lower side of the basic size
On any one side of the basic size
On both sides (upper & lower) of the basic size
Correct answer- (D)
10) Best example for driving fit is
Ball bearing on the shaft
Tyre on the rail wheel
Pulley with key on the shaft
Cart rim on the wooden wheel
Correct answer- (A)
11) Best examp for shrinkage fit is
Cart rim on wooden rim
Tyre on the rail wheel
Tyre on the bicycle rim
Flywheel on the shaft
Correct answer- (A)
12) In hole basis system
The size of the shaft is made constant
The size of the shaft is made constant
The permissible tolerances are given on the hole and the shaft
Allowance is given only on the hole
Correct answer- (B)
13) Tolerance is given to the part size to
Increase the production
Decrease the production
Finish the components approximately
Produce the parts within the required permissible size error
Correct answer- (d)
14) As per BIS system of limits and fits, there are 18 grades of tolerances represented by number symbols from
ITOI, IT1 … to 1T16
IT1 … to 1T18
ITO … to 1T17
ITO1, ITO, IT1 to 16
Correct answer- (D)
15) The size of a component is given as 24 — 0.1. What does —0.1 indicate?
Upper deviation is + 0.1 mm
Lower deviation is 0.0 mm
Fundamental deviation is 0.0 mm
Lower deviation is — 0.1 mm
Correct answer- (D)
16) In the assemblies obtained by using the system of limits and fits, the damaged parts
cannot be replaced
are required to be scrapped
may be easily replaced without rejecting the assembly
have to be made with new tolerance
Correct answer- (C)
17) In the BIS system of limits and fits the standard range of sizes covered are
0 to 500 mm
25 to 400 mm
0 to 100 mm
0 to 10 mm
Correct answer- (A)
18) The tolerance of a hole is the difference between the
Maximum hole size and maximum shaft size
Maximum hole size and minimum hole size
Minimum hole size and maximum shaft size
Maximum hole size and minimum shaft size
Correct answer- (B)
19) The three classes of fits as per BIS system are
Clearance fit, transition fit and interference fit
Medium fit, push fit and tight fit
Flat fit, round fit and square fit
Sliding fit, loose fit and shrinkage fit
Correct answer- (A)
20) In the BIS system of limits and fits, 25 hole deviations are specified by using
Small letters
Capital letters
Small letters with tolerance
Small letters with numbers
Correct answer- (B)
21) Which one of the following statements is correct?
Interchangeability of parts may be obtained by adopting the system of limits and fits
The BIS system of limits and fits does not give the desired fit
Interference fit is always designed with a positive clearance
Transition fit is always specified with a negative clearance
Correct answer- (A)
22) The first step of quality control is the product specification. On who’s opinion is the product specification based?
Marketing department
Consumer / user
Sales department
Servicing department
Correct answer- (B)
23) Mass-produced components should be interchangeable. One of the following is the most important factor required to achieve the interchangeability in mass production ?
Dimensional accuracy
Standardisation
Geometrical accuracy
Surface finish
Correct answer- (B)
24) Threaded components both external and internal are manufactured with thread tolerance. One of the reasons for having thread tolerances is to
Ensure interchangeability of threaded parts
Identify and group up threaded assemblies by labeling
Determine the percentage of thread of both bolt and nut
Obtain qualitative surface finish
Correct answer- (A)
25) In the BIS system of limits and fits, the grades of tolerance are represented by number and there are
18 grades of tolerances
16 grades of tolerances
14 grades of tolerances
20 grades of tolerances
Correct answer- (A)
26) Which among the following is the correct statement?
A clearance fit always provides interference
An interference fit always provides clearance
An interference fit may sometime provide clearance and sometime interference
A transition fit may sometime provide clearance and sometime interference
Correct answer- (D)
27) A hole whose lower deviation is zero is called basic hole. Which one of the following letters indicates basic hole ?
E
F
G
H
Correct answer- (D)
28) Under the terminology of the IS system of limits the term ‘tolerance’ is defined as the difference between the
maximum limit and the basic size
minimum limit and the basic size
maximum limit and minimum limit
actual size and basic size
Correct answer- (C)
29) If the dimension of a component is finished within the limits of size, then it will be —
Minimum size
Basic size
Acceptable size
Rejected size
