CONCORDIA UNIVERSITY
FACULTY OF ENGINEERING AND COMPUTER SCIENCE
Department of Mechanical and Industrial Engineering
ALTERNATIVE FINAL EXAMINATION- MACHINE DRAWING AND DESIGN, MECH 313/4, WINTER 2010
Instructors: Dr. Javad Dargahi, Dr. Sivakumar Narayanswamy, Dr John Cheung, Dr. Suraj Joshi
Open book examination
Date of the examination: April, 2010
Duration of the examination: 3 hours
Maximum Marks: 100
Materials allowed: Faculty approved calculators, Text book, Copy of bearing tables and limits and fits
tables for Metric system.
Answer the questions in the space provided
Student’s name: . . . . . . . . . . . . . . . . . . . . . . . .
Student’s surname: . . . . . . . . . . . . . . . . . . . . . .
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Signature: . . . . . . . . . . . . . . . .
Question 1. (20 multiple choice questions - 20 marks)
1. What symbol is used to indicate a spherical diameter on a drawing?
A.
RØ
B.
SØ
C.
SPØ
D.
SPHØ
2. Which is the correct method to dimension the taper on a drawing?
A.
The diameters of both ends and the length of the taper.
B.
The length of the taper and the rate of taper.
C.
The included angle and the taper diameter of one end.
D.
Diameters of both ends
3. How are the non-aligned features of an object represented in a sectional view?
A.
Draw an off-set section view
B.
Draw a full section view
C.
Draw a half section view
D.
Draw a full section view for each individual non-aligned feature
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4. A dowel pin of Ø 10.000 – 10.015mm is fitted to a dowel hole of Ø 10.023 – 10.032mm in a
plate. Calculate the pin and hole tolerances respectively.
A.
0.023mm, 0.015mm
B.
0.015mm, 0.009mm
C.
0.009mm, 0.017mm
D.
0.009mm, 0.015mm
5. What are the reasons to control surface finish of a component?
i)
Heat reduction
ii)
Appearance improvement
iii)
Service life improvement
iv)
Process time reduction
A.
i, ii and iii
B.
ii and iv
C.
i and ii
D.
iii and iv
6. A basic dimension is
A.
a geometric characteristic, the size of which is specified.
B.
the maximum permissible variation of form.
C.
the total permissible variation in the size of a dimension.
D.
a theoretical exact size, profile, orientation of location.
7. The overall envelope of perfect form within which a feature would just fit is
A.
tolerance zone
B.
virtual condition
C.
profile
D.
feature control frame
8. A condition in which all surface elements are on one plane is
A.
flatness per unit area.
B.
straightness of a surface.
C.
flatness of a surface.
D.
profile of a surface.
9. Features of size should have
A.
a reference to a datum.
B.
diameter or thickness.
C.
a virtual envelope.
D.
a correlative geometric condition.
10. Coplanarity and concentricity are examples of _____________ geometric tolerancing.
A.
positional
B.
virtual
C.
correlative
D.
all of the above
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11. Which of the following is correct?
A.
Roller bearings are more satisfactory under shock or impact loading than ball bearings.
B.
If there is misalignment between housing and shaft, either a self-aligning thrust or a
spherical ball bearing should be used.
C.
At low speeds, a deep-groove or angular contact ball bearing will usually be a better
choice even for pure thrust loads.
D.
Self-aligning ball bearings and cylindrical roller bearings have high friction coefficients.
12. Which of the following is (are) correct:
i)
ii)
A.
B.
C.
D.
Vibration direction must not be parallel to the axis of the pin
The shear plane of the pin must be more than 1 dia. from the end
i
ii
i and ii
Neither i nor ii
13. Which of the following statement(s )is correct when set screw is used in combination with key
i)
ii)
A.
B.
C.
D.
the setscrew locates the part in axial direction only
the torsion load on the part is carried by the key
i
ii
i and ii
Neither i nor ii
14. The Lead is the
A.
distance from a point on the thread form to a corresponding point on the next form,
measured parallel to axis
B.
distance from a point on the thread form to a corresponding point on the next form,
measured normal to axis
C.
distance the fastener would move parallel to the axis in a 2π counterclockwise rotation of
the head
D.
distance the fastener would move normal to the axis in a 2π counterclockwise rotation of
the head
15. The choice of an appropriate fastener generally will not depend on
A.
whether the assembly is located next to another assembly
B.
whether the assembly bears load in tension or shear
C.
whether the assembly is subject to impact or vibration loading
D.
whether the assembly should look aesthetically pleasing
16. In a belt drive, the purpose of the idler pulley is to
A.
impart extra power in transmission
B.
impart extra tightness to the belt
C.
accommodate for the extra width of the belt
D.
accommodate for the manufacturing defects in the belt
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17. Gears transmit power at
A.
constant linear acceleration
B.
constant angular acceleration
C.
constant linear velocity
D.
constant angular velocity
18. In a rack and pinion arrangement,
A.
the rack is a spur gear while the pinion is a linear gear
B.
the rack is a linear gear while the pinion is a spur gear
C.
both the rack and pinion are linear gears
D.
both the rack and pinion are spur gears
19. Which of the following statement(s) is (are) correct:
i)
For metal parts the recommended pitch distance is more than three
times the diameter of the largest rivet
ii)
For plastic parts the recommended pitch distance is more than five times
the diameter of the largest rivet (Unless it produces stress concentrations)
A.
i
B.
ii
C.
i and ii
D.
Neither i nor ii
20. Which of the following statement(s) is (are) correct:
i)
Spot-weld fasteners are used when appearance of the part surface
opposite to the weld is not critical,
ii)
Projection-weld fastens are used when appearance of the part surface
opposite to the weld is critical.
A.
i
B.
ii
C.
i and ii
D.
Neither i nor ii
Question 2. (10marks)
a) Calculate the positional tolerancing to coaxial features shown in the figure such that the ratio of
T1:T2 is 3:2
b) What will be the allowable distance between the axes of 2 features in the shaft if
a. Both the features are at MMC
b. Both the features are at LMC
c. Datum at MMC and the other feature at LMC
d. Datum at LMC and the feature at MMC
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Question 3. (25 marks)
Complete the figure of the stepped shaft given in the next page, with the information below.
All datums and tolerances are to be on MMC basis unless otherwise specified.








The end face A of Ø 90 is Datum A. It is to be flat within 0.25mm
The shaft B (Ø 44) is Datum B. It has an h6 sliding fit. Show the limits of size for B. It also has a
straightness tolerance of 0.1mm.
The shaft F (Ø 20) has an h9 free running fit. Show the limits of size for shaft diameter F.
The width of the slot C is datum C. The width is 18.00 – 18.20mm. It is perpendicular within
0.05mm to Datum A. It also has a positional tolerance of 0.1mm and is referenced to Datums A,
and B in that order.
The two holes D (Ø 12) are equally spaced on Ø 68mm. These two holes must not vary from
their true positions by more than 0.2mm and are referenced to Datums A, B and C in that order.
The two holes E (Ø 8) are equally spaced on Ø 68mm. They have a positional tolerance of 0.1mm
and are referenced to Datums A, B and C in that order.
The surface of the end face A of Ø 90 has a machining surface roughness value of 0.8μm and a
machining allowance of 0.15mm.
The shaft surfaces of both diameters B (Ø 44) and F (Ø 20) are to have a surface finish of 0.4μm.
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Question 4. (15 marks)
Complete the power drive assembly shown in Fig given the following information. The shaft is
positioned in the housing by an SKF #6005 bearing. The end cap and a retaining ring hold the bearing in
place, and a retaining ring holds the cap in the housing. Two retaining rings position the bearing on the
shaft. The gear is positioned on the clutch by retaining ring and a square key. The clutch is locked to the
shaft by a square key held in position by a set screw. You need to identify the following parts in the
drawing shown below from tables: Bearing, retaining rings, key sizes, set-screw type. Scale the drawing
for dimensions not shown.
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Question 5. (20 marks)
Complete the assembly drawing shown. The shafts for the gearbox are supported by two plain bearings
press-fitted into the gear box. Select suitable 8 pitch (3.18 MDL) 20 spur gears from manufactures’
catalogs that revolve the smaller shaft four times as fast as the larger shaft. Lock the pinion to the shafts
using setscrews and retaining rings and lock the gear to the shaft using flat key and setscrews. Drawing
is not to scale. Use A= 95.4mm, B = 20 mm and C = 25 mm.
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Question 5. (10 marks)
A .5 hp, 1750 rpm motor drives a power hacksaw. The shaft on the hacksaw is to run at approximately
750 rpm, and the center-to-center distance of the shafts is 15.5 in. Calculate the size of the V-belt
required with a heavy duty classification.
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