Chapter 06 – Process Selection and Facility Layout
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Education.
12. Arrange the departments into a 2 x 4 grid. Department 1 must be located in the shaded location.
First, we transfer the Muther grid information to a table as shown below:
A Links
X Links
E Links
I Links
1-3
1-6
1-2
4-6
1-7
2-6
1-4
2-3
3-6
1-5
2-4
3-7
2-5
2-7
3-8
6-7
3-5
5-6
4-7
4-8
6-8
7-8
Rather than drawing clusters, we can start with a blank layout and then try to satisfy the A
and X conditions above. After that, we can shift departments around to satisfy E conditions
followed by I conditions.
conditions above, we can see that Department. 6 should only be located by Departments 4, 7, or
8. We can shift departments more if needed using trial and error to meet E conditions and then I
conditions.
The layout below meets all conditions. The next page shows all of the possible layouts
that meet all conditions.
3
1
4
8
5
2
7
6
Chapter 06 – Process Selection and Facility Layout
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Education.
All possible layouts for Problem 12:
3
1
4
8
Or
5
1
4
8
Or
5
1
4
6
5
2
7
6
3
2
7
6
3
2
7
8
5
1
7
8
Or
3
1
7
8
Or
3
1
4
6
3
2
4
6
5
2
4
6
5
2
7
8
3
1
7
6
Or
5
1
7
6
5
2
4
8
3
2
4
8
13. Given: We must arrange departments in a 3 x 3 grid, and Department 5 must be located in the
lower left corner (shown in the shaded area in the layout).
We start by placing the Muther grid information into a table.
A Links
X Links
E Links
I Links
1-3
1-2
1-4
2-4
1-7
1-6
1-9
1-8
2-3
2-9
2-5
3-4
3-7
2-6
3-6
4-8
2-7
3-8
6-7
3-9
4-5
4-6
4-9
4-7
5-6
5-7
5-8
5-9
6-9
7-8
8-9
7-9
Chapter 06 – Process Selection and Facility Layout
Looking at the A links, we can see that that Department 7 appears most frequently followed by
Departments 1, 2, 5, & 9, and then Departments 3, 4, 6, & 8.
Department 7 is a good candidate for a central location. Then, we satisfy the remaining A
conditions along with the X conditions. After that, we can use trial and error to move departments
Chapter 06 – Process Selection and Facility Layout
6-44
From this, we can see that Departments 2 and 4 have the greatest interdepartmental workflow, so
they should be close, perhaps at Locations C and B. Next, we can see that the workflows for
Departments 1 and 4, and Departments 3 and 4 are high. Therefore, Department 4 has to be
located at a central location (Location B), while Department 2 is in Location C, Department 1 is
in Location A, and Department 3 is in Location D as shown below.
A
#1
B
#4
C
#2
D
#3
Second, we must determine the cost for each department pair by multiplying Number of Trips
x Distance x $1.
Number of Trips x Distance x Cost ($1)
Department
1
2
3
4
1
10 x 80 x 1 = 800
20 x 70 x 1 = 1400
80 x 40 x 1 = 3200
2
40 x 60 x 1 = 2400
90 x 40 x 1 = 3600
3
55 x 50 x 1 = 2750
4
Total Cost = $14,150
b. Revised layout given the new number of trips between departments.
First, we rank or arrange the number of trips between departments from high to low.
Dept. Pair
# of Trips
3-4
60
2-4
50
1-4
40
1-2
20
1-3
20
2-3
10
Chapter 06 – Process Selection and Facility Layout
6-45
From this, we can see that Departments 3 and 4 have the greatest interdepartmental workflow, so
they should be close, perhaps at Locations C and B. Next, we can see that the workflows for
Departments 2 and 4, and Departments 1 and 4 are high. Therefore, Department 4 has to be
located at a central location (Location B), while Department 2 is in Location A, and Department 1
is in Location D.
Second, we must determine the cost for each department pair by multiplying Number of Trips
x Distance x $1.
Number of Trips x Distance x Cost ($1)
Department
1
2
3
4
1
20 x 70 x 1 = 1400
20 x 60 x 1 = 1200
40 x 50 x 1 = 2000
2
10 x 80 x 1 = 800
50 x 40 x 1 = 2000
3
60 x 40 x 1 = 2400
4
Total Cost = $9,800
A
#2
B
#4
C
#3
D
#1
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Education.
15. Given: Work centers 1 & 3 must be positioned in the diagram below as shown in the shaded
areas. We have 8 work centers that we must arrange in the layout. Transportation costs are $1 per
load per meter. Assume that reverse distances are the same.
C
D
E
First, we will assign work center pairs based on ranking them by number of trips between them.
No. of Trips
Between
Order of
Assignment
12
10
13
5
14
90
11
15
370
1
16
135
6
17
125
7
18
0
23
360
2
24
120
8 (tie)
25
40
26
115
9
27
45
28
120
8 (tie)
34
350
3
35
110
10
36
40
37
20
38
200
4
45
190
5 (tie)
46
70
12
47
50
48
190
5 (tie)
56
10
57
40
58
10
67
50
68
20
78
20
A
#1
B
F
G
H
Chapter 06 – Process Selection and Facility Layout
Education.
From this, we can see that work centers 1-5 have the highest number of trips between them,
followed by work centers 2-3, 3-4, 3-8, 4-5, 4-8, 1-6, 1-7, 2-4, 2-8, etc.
A reasonable (intuitive) set of assignments is:
C
#7
D
#4
E
#3
The distance (in meters) between work centers for this option is shown below:
From
To
1
2
3
4
5
6
7
8
1
100
120
60
40
80
40
110
2
50
40
120
40
70
40
3
40
60
90
85
40
4
40
50
45
45
5
140
60
130
6
40
60
7
90
8
Then, for each work center pair, we must multiply Number of Trips x Distance x $1.
Number of Trips x Distance x $1
From
To
1
2
3
4
5
6
7
8
1
1000
600
5400
14800
10800
5000
0
2
18000
4800
4800
4600
3150
4800
3
14000
6600
3600
1700
8000
4
7600
3500
2250
8550
5
1400
2400
1300
6
2000
1200
7
1800
8
A
#1
B
#5
F
#6
G
#2
H
#8
Chapter 06 – Process Selection and Facility Layout
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Education.
16. Given: Distance between the reception area and each potential location (A, B, C, D, E, & F) = 35
feet. The reception area must remain in the central location; therefore, we can omit the reception
area from our analysis.
First, we will list the department pairs and the number of trips between them.
No. of Trips
Between
Order of
Assignment
12
0
10
13
40
7 (tied)
14
110
3
15
80
5
16
50
6 (tied)
23
0
10 (tied)
24
50
6 (tied)
25
40
7 (tied)
26
120
2
34
10
9 (tied)
35
250
1
36
10
9 (tied)
45
40
7 (tied)
46
90
4
56
20
8
Second, we will assign departments based on ranking the number of trips between departments.
A reasonable set of assignments is:
3A, 5B, 1C, 4D, 6E, 2F.
An equivalent solution is the reverse order:
2F, 6B, 4C, 1D, 5E, 3F.