Kingdom of Saudi Arabia
Ministry of Higher Education
Majmaah University
College of Engineering
Department: Mechanical and Industrial Engineering
Max Marks: 20 Home Assignment
Subject: Computer aided manufacturing (ME 415) Submission: April25, 2014
Attempt all the questions:
QN1. Write the part program G and M codes using multiple turning cycle G71 for the turned part as
shown below.
[5]
The Billet is of 80mm length and 50 mm diameter. The radius of curve R is 25 mm
R
40
R
20
15
30
 20
10
20
15
QN2. Write the single turning cycle Code and taper turning codes for the final shape of work piece
turned from turned from cylindrical billet of 80 mm length and 40mm diameter.
[5]
40
20
40
20
20
QN3. An automobile factory operates 8 hrs a day and 4days in a week. There is 40 minutes break
during each shift. There is production demand of 1500 units per week. The tasks and precedence
constraints are given below.
[5]
Task
Activity
a
b
c
d
e
f
Fix front Axle
Fix Engine Frame
Place engine body
Insert rear axle wheels
Insert Hood
Fix windows
Time of
element
(Seconds)
20 sec
06
05
21
08
35
work precedence
a
b
-
g
h
i
j
k
l
Assemble
gear
assembly
Insert spacers
Secure front wheel
Insert cooling system
Attach sheet metal
cover
Add safety devices
15
c, d
10
15
05
46
g
e, h
c
f, i, j
16
k
Based on largest candidate rule, How many work stations are required?
ii) What work elements each work station constitute?
iii) Calculate balance delay.
Q.4 a) Explain the followings; i) PEDIT command, Ortho mode, offset, polar array, face rotate, and slice
[2]
b) A transfer line is used to produce valves. The ideal cycle time is 1.0 minutes. The frequency of
failures of transfer line is 10 break downs /hr. The down time per break down is 15 minutes. The
estimated scrap rate is 5%. The operating cost of transfer line is $200/hr. The cost of tooling and
disposables per product is $ 0.25. The cost of input raw material is $ 1.5. Compute:
i) Production rate
[3]
ii) Transfer line efficiency
iii) Cost of unit production