MGT 345 OPERATION MANAGEMENT UITM

1. CHAPTER 4
FACILITY LAYOUT
(MGT345)

2. Chapter outline:
4.1 Definition of layout
4.2 Objectives of facility layout
4.3 Factors influencing layout
4.4 Types of layout
4.5 Assembly line balancing

3. 4.1 Definition
 The physical arrangement of equipments, departments,
rooms and so on, within an organisation with a description
of resources locations and their relationship to each other.
 Overall arrangement of machines, departments, work
centers, equipments, material handling, service facilities to
facilitate movement of work, customers or materials
through system.
To develop an effective and efficient layout that will meet
firm competitive requirements.

4. 4.2 Objectives of Layout Planning
1. To utilization of space, equipment and people
- minimize distance and reduce unnecessary movements
in manufacturing process. For example is cafe and
restrooms located close to workers.
2. To have efficient flow of material in production process
- reduce idle time in operation process. For example
machine arrangement.
3. To improve employee morale and safety
- convenience physical environment affect productivity
level for example comfortable and clean environment.

5. 4. To minimize material handling costs
-arrangement of equipment is represent cost that
company need to bear. For example is movement of
material and labor can increase the material handling
costs.
5. To have flexibility
- it is used to consider new process in production. For
example producing new product may request new
machines or equipments.

6. 4.3 Factors Influencing Layout
a) Types of product
Each product design may request different activities or
equipment.
b) Characteristics of material
Materials used in production handle by different
equipment.
c) Nature of manufacturing process
Machines and technology used in operation process
d) Volumes of production
Arrangement of machines affect by facility design.
e) Types of production/operations methods
Three are types which is product, process and project.

7. 4.4 Types of Basic Layout
1. Product Layout
- an arrangement of resources in a straight-line fashion
to promote efficient production and meet the needs
of the product.
- to produce high volume of product, company need to
have high equipment utilization.
- product is standardized and investment only for
specialized equipments that use in operation.
2. Process Layout
- arrangement of facilities whereby work centers and
department are grouped together according to the
functions.
- to deals with low volumes but high variety of
production. This process similar. Output not request
specialized equipments.
- Customized products

8. 3. Fixed Position Layout
- product stays at one place; tools, equipments and
workers are brought to it; suitable for large heavy or
fragile products.
- Workers and equipment come to production site
- the project remains in one place and workers and
equipment come to that one work area.

9. Product Layout Analysis
It is the best way to conduct an analysis using formula and
diagram. The purposes of product layout analysis are;
1) To determine how many workstations to create
and assigning tasks to each work station.
2) Meets required capacity demand
3) Sequence is technical feasible
4) It is an efficient line

10. Terms in Product Layout Analysis
a) Precedence diagram
A flowchart showing sequential relationship among tasks. Circles
represent tasks and arrows represent precedence.
b) Task time
Time needed to perform a task.
c) Productive time
The amount of time in minutes or seconds workers work excluding
work allowances.
d) Cycle Time
Longest task time.
e) Idle time
Total unproductive time for all workstations due to inequality of
times among workstations.

11. Product Layout Analysis
f) Workstation
A physical area where workers with tools, machine(s) perform a
particular set of tasks.
g) Bottleneck
A situation of the production rate is slowed down due to an
earlier process is faster than the latter.
h) Minimum number of work stations
The least workstations required in production.
i) Actual number of work stations
The number of workstations required in production.
j) Line Balancing
To equalize time in all workstation in order to minimize idle time

12. 4.5 Assembly Line Balancing
It is an analysis of production lines to divides work between
workstations while meeting required output. Besides that,
it’s able to maximize efficiency and minimize number of
workstations.
Formula Related to facility layout
1. Maximum Daily output = Available time per day
Cycle Time
2. Cycle Time per unit = Available time per day
Maximum daily output
3. Minimum number of workstations = Total task time
Cycle time
4. Total productive time = Total task time

13. 5. Efficiency = Total Task Time
(No. of actual workstation X Cycle Time) x 100
6. Idleness or balance of delay = 100% - Efficiency
7. Daily labor hours idle;
a) Idle time per cycle = (Cycle time x actual workstation) – total task time
b) Daily labor idle = Idle time per cycle x maximum daily output
Seconds or minutes per hour
8. Cost of idleness
a) Cost of idleness = hour wage x daily labor hour idle x working days
OR
b) Cost of idleness = Idleness x (wages x working days/week/month) x
actual number of workstation

14. 4.6 Step Preparing the precedence
diagram
a) Construct sequence of activity by referring to
predecessors
b) Follow the activity requirements step by step in order
to form the sequence of activities
c) Every activity came from the same or different
predecessors
d) Put the time allocation from of this line layout
e) By trial-and-error (or more sophisticated means), try to
improve the initial layout. It is requested in line
balancing.

15. Example 1
Activities/Task Work Precedence Time (minutes)
A - 2
B A 1
C A 2
D B,C 3
E D 3
F E 3

16. A
B
D
E
F
C
2 3
3
3
2
1

17. Example 2
Task Precedence Tasks Time (Minutes)
A - 10
B A 11
C B 5
D B 4
E A 12
F C,D 3
G F 7
H E 11
I G,H 3

18. Example 3
Task Precedence Tasks Time (Minutes)
A - 5
B A 3
C B 4
D B 3
E C 6
F C 1
G D,E,F 4
H G 2

19. Example 4
TASK Precedence
Tasks
Time (minute)
A - 0.12
B A 0.30
C B 0.36
D C 0.25
E D 0.17
F D 0.05
G E,F 0.10
H F 0.08
I G,H 0.25

20. 1. Precedence diagram
A
I
H
G
F
E
D
C
B
A B C D
E
F G
H
I
0.17 mins
0.05 mins0.36 mins0.30 mins0.12 mins
0.08 mins
0.25 mins0.10 mins
0.25 mins
De-tin and trim
0.12 minutes
Decorate, blue icing
0.10 minutes
Decorate, green icing
0.05 minutes
Reshape with off-cuts
0.30 minutes
Clad in almond fondant 0.36
minutes
Clad in white fondant 0.25
minutes
Decorate, red icing
0.17 minutes
Affix transfers
0.08 minutes
Transfer to base and
pack 0.25 minutes
Total work content = 1.68 minutes

21. 2. Cycle time
The initial order from the supermarket is for 5,000
cakes a week and the number of hours worked by the
factory is 40 per week. The labor cost is RM4.50 per
hour.
Required cycle time
= 40 hours x 60 minutes / 5000 cakes
= 0.48 minutes/cake

22. 3. Theoretical minimum no. of
workstations
Theoretical number of workstations
= 1.68 mins (total task time) / 0.48 mins
= 3.5 units @ 4 units
In practice this means that four units will be
needed.

23. 4. Assembly line balancing
A B
C D
E
F G
H
I
0.17 mins
0.05
mins
0.36
mins
0.30
mins
0.12
mins
0.08 mins
0.25
mins
0.10
mins
0.25
mins
WS 1 WS 3WS 2 WS 4
Task time 0.42 0.36 0.42 0.48
Idle time 0.06 0.12 0.06 0.00 = ∑ 0.24

24. 5. Efficiency and balance delay
Efficiency
= 1.68 / (4 x 0.48)
= 87.5%
Balance delay/Proportion of idle time per cycle
= 100% - 87.5%
= 12.5%
Or
Idle time = (0.48 – 0.42) + (0.48 – 0.36) + (0.48 – 0.42)
= 0.24 minutes
Balance delay = 0.24 / (4 x 0.48)
= 12.5%

25. 6. Cost of idleness
1. Idle time per unit = 0.24 mins
2. Idle time per week = 0.24 mins x 5000 cakes
= 1200 mins
3. idle time (hrs)/week = 1200 mins / 60 mins
= 20 hrs
4. Cost of idleness per week
= 20hrs x RM4.50/hr
= RM90

26. Example 1 (b)
Activities/Task Work Precedence Time (minutes)
A - 2
B A 1
C A 2
D B,C 3
E D 3
F E 3

27. A
B
D
E
F
C
2 3
3
3
2
1

28. 1. Construct the precedence diagram
2. If the demand is 120 pizzas per day and their
working hours is 8 hours per day, compute the
cycle time for the process.
3. Balance the line with proper diagram
4. Compute the efficiency and balance of delay
5. If the wages paid RM20 per day, compute cost of
idleness per week. Assume 6 days per week

29. 1. Cycle Time per unit = Available time per day
Maximum daily output
= (8 x 60) / 120
= 4 minutes
2. Minimum number of workstations = Total task time
Cycle time
= 14/4
= 3.5 workstations @ 4
workstations
3. Balance the line with proper diagram
W1 W2 W3 W4
Total Time 4 4 3 3
Idle Time 0 0 1 1 ∑ 2 minutes
A, C B,D E F

30. 4. Compute the efficiency and balance of delay
Efficiency = Total Task Time
(No. of actual workstation X Cycle Time) x 100
= 14 / { ( 4 x 4) x 100 }
= 87.5%
Idleness or balance of delay = 100% - Efficiency
= 100% - 87.5%
= 12.5 %
5. If the wages paid RM20 per day, compute cost of idleness per week.
assume 6 days per week
Cost of idleness= Idleness x (wages x working days/week/month) x
actual number of workstation
= 12.5% x (RM20 x 6) x 4 workstations
= RM60

31. PAST YEAR PAPERS (2007 – 2011)
 Apr 2011 (A2)
 Sept 2011
 Oct 2010 (A5)
 Apr 2010 (B4)
 Oct 2009 (A4)
 Apr 2009 (Nil)
 Oct 2008 (B4)
 Apr 2008 (Nil)
 Oct 2007 (A2, B5)
 Apr 2007 (B3)

32. Tutorial
April 2011 (a1)
a)
A B
C
D
E
F
G
H
I
0.56 0.62
0.11
0.43
0.22
0.09
0.34
0.35
0.21
J
0.57
0.33
K

33. b) Maximum Daily = Available time per day
Cycle Time
= 400 minutes/0.62
= 645. 2 units
c) Minimum number of workstations = Total task time
Cycle time
= 3.83 min / 0.62 min
= 6.2 workstations ≈
= 7 workstations
d) Balance the line with proper diagram
W1 W2 W3 W4 W5 W6 W7
Total Time 0.56 0.54 0.43 0.62 0.57 0.57 0.54
Idle Time 0.06 0.08 0.19 0 0.05 0.05 0.08 ∑ 0.51
minutes
A, E G F,HB, C,D J I,K

34. e. Compute the efficiency and balance of delay
Efficiency = Total Task Time
(No. of actual workstation X Cycle Time) x 100
= 3.83 / (7 x 0.62) x 100
= 88.25%
Idleness or balance of delay = 100% - Efficiency
= 100% - 88.25%
= 11.75 %
f) Cost of idleness = Idleness x (wages x working days/week/month) x
actual number of workstation
= 11.75% x (RM50 x 5) x 7 workstations
= RM205.63