it is useful for power student

1. Chapter 3
Plant Design
1

2. Chapter Outline
 Definition of Plant Design
 Plant/Facility location
 Selection of General and Specific Territories
 Analytical Plant Location Methodology
 Definition of Plant Layout
 Types of Plant Layout
 Ergonomics 2

3. Plant Design
Plant design is a broad function-taking place
in the origin of an enterprise.
• It is the planning of finances, the plant
location and all the planning necessary for
the physical requirements of an overall
design of a plant.
• The basic decision that must be taken for
effective plant design include:

4. Plant design cont’d
o Product design
o Process design
o Capital acquisition
o Sales planning
o Make or buy
o Product price range
o Plant location
o Plant layout
o Diversification
o Building type selection 4

5. Plant design …..Cont’d
i) Product Design:
The design of the product is the foundation upon which a
plant layout is built.
 Design for function: in order to create a satisfied
customer or to attract customers, a product must
perform the function for which its customer intends to.
 Design for manufacturing: a product that solves the
functional problem nicely, but is impossible to
manufacture, is worthless.
 Design for selling: a product that functions
well and easy to make, but wanted by no one is
useless.(Design of distribution/selling) system

6. Cont’d…
(ii) Process Design (Determination of the Production
Process:)
• Encompass the selection of a process, choice of
technology, process flow analysis and layout of the
facilities
(iii) Capital Acquisition: Obtaining capital for the
initial establishment;
♣ Raising funds to cover operating costs;
♣ Secure funds for expansion.
The primary sources of capital are:
♣ Personal savings;
♣ Loans and sales of bonds;
♣ Profit plowback

7. Cont’d
(iv) Sales Planning:
It is important to know the market demand with the
understanding of seasonal variation.
(v) Make or Buy:
The determination of unit cost is usually the first step
in a make-buy analysis. In such analysis management
is interested in:
♣ Reducing unit material and processing costs;
♣ Minimizing cash investment;
♣ Improving product.

8. Cont’d
(v) Plant Size:
The size of a plant dependent upon the volume of
output proposed for it.
vi) Product Price Range:
The choice of competent price range will influence the
quality, quantity and the manufacturing process of the
product.
vii) Plant Location:
Selecting a location involves large commitments of
capital as a result it must be done with utmost care.

9. viii) Plant Layout:
It is the plan of, or the act of planning, a good
workable disposition of industrial facilities,
like operating equipment, storage space,
materials handling equipment and all other
supporting services, along with the design of
the best structure to contain these facilities.
9

10. 10

11. Plant design …..Cont’d
ix) Building Type Selection:
Selection of the type of building will take place before,
or during the plant layout phase.
x) Diversification:
To diversify doesn't mean widening the scope of the
presently manufactured line, but rather mean entering a
completely new field(planning new products).
xi) Organization Development:
The manner in which the overall objectives of an
enterprise are clearly defined, the objectives of various
subdivisions are determined and clearly specified
influences the arrangement of plant facilities.

12. Plant/Facility Locations
What is plant location?
 Refers to the choice of region and the selection of a
particular site for setting up a business or factory.
 To get advantage by virtue of location.
 It is a strategic decision that cannot be changed
once taken.
 A facility is something built or established to serve a
purpose and facilities location is the determination
of the site for that facility. It is part of a larger study
area called facility’s management, which involves
both the location of the facility and the composition,
or internal layout of the facility once located.
12

13. Plant/facility Location …Cont.
There are analytical procedures to aid in the process
but the decision must also included factors that are
difficult and impossible to quantify.
What is an ideal/best location?
♣ Is one where the cost of the product is kept to
minimum, with a large market share, the least risk
and the maximum social gain.
♣ It is the place of maximum net advantage or which
gives lowest unit cost of production and distribution.

14. Plant location …(Cont…)
 Do you think the location of Gypsum
Board or Dejen Cement factory in East
Gojjam is correct?
 Why?
14

15. Plant location/Site Selection
1. Selection of General Territory
2. Selection of a Specific Site
15

16. Selection of General Territory
♣ Calls for information of a more general nature
Factors that affect the choice of territory includes:
i. Location of market/Proximity to Market:
Market oriented plants; Space required for output
>>> space required for input.
i.e. Car manufacturing, Appliances.
ii. Cost of construction:
iii. Location of raw material: Raw material oriented factories;
weight of input >>> weight of output.
16

17. Selection of general territory…(Cont..)
iv. Transport
♣ The transport of materials and products to and
from plant will be an overriding consideration in
site selection.
♣ If practicable, a site should be selected so that it
is close to at least two major forms of transport:
road, rail, waterway or a seaport.
17

18. Selection of general territory…(Cont..)
v. Labors and wages:
♣ Quality of labor force
♣ Availability of labor force
♣ Unemployment rate
♣ Labor unions
♣ Attitudes towards work and labor turnover
♣ Motivation of workers and work force
management
vi. Energy: other than electric power, in some plants
it is necessary to use gas, coal, fuel-oil, etc…
18

19. Selection of a Specific Site
Factors affecting includes:
i. Community: the plant has to be located according to
the master plan of the city or region.
ii. Transport: it is important to consider the
transportation infrastructure of the area.
iii. Availability of utility, electricity, water,……
 Aluminum plant is strongly dependent to the
electricity
 Blast furnace requires a high flow of water
iv. Future development: the plant has to be in position
to develop or change product quantity, type and size.
19

20. Selection of a Specific Site…(Cont)
iv. Wind direction: if the industry produces smoke, gas,
odor, etc…
v. Condition of the site: the grounds has to have a good
resistance to the load induced by the foundation of the
building.
vi. Complementary plants: an industry to produce as
intended, may need material, service and assistance
from other plants.
viii. Cost of living
 Health care
 Education
 Construction costs. 20

21. Principal factors must be considered selecting a
suitable plant site, can be summarized:
1. Raw material
availability.
2. Marketing area.
3. Availability of suitable
land.
4. Transport facilities.
5. Availability of labors.
21
6. Availability of utilities (Water,
Electricity).
7. Environmental impact and effluent
disposal.
8.Local community considerations.
9.Climate.
10.Political strategic considerations.
11. Taxations and legal restrictions

22. Analytic Plant Location Methodology
22
1. Location Rating Factor analysis
Steps for location factor analysis;
1. Identify important factors
2. Weight factors (0.00 - 1.00)
3. Subjectively score each factor (0 - 100)
4. Sum weighted scores

23. Plant Location Methodology
Location Factor Rating: Example
23
1. Labor pool and climate
2. Proximity to suppliers
3. Wage rates
4. Community environment
5. Proximity to customers
6. Shipping modes
7. Air service
LOCATION FACTOR
.30
.20
.15
.15
.10
.05
.05
WEIGHT
80
100
60
75
65
85
50
Site 1
65
91
95
80
90
92
65
Site 2
90
75
72
80
95
65
90
Site 3
SCORES (0 TO 100)
Weighted Score for “Labor pool and climate” for
Site 1 = (0.30)(80) = 24

24. Plant Location Methodology
Location Factor Rating
24
Site 3 has the highest
factor rating
24.00
20.00
9.00
11.25
6.50
4.25
2.50
77.50
Site 1
19.50
18.20
14.25
12.00
9.00
4.60
3.25
80.80
Site 2
27.00
15.00
10.80
12.00
9.50
3.25
4.50
82.05
Site 3
WEIGHTED SCORES
Best Site is 3

25. Plant Location Methodology:
2. Center of Gravity Method
 The center of gravity method is used for locating
single facilities that considers existing facilities,
the distances between them, and the volumes of
goods to be shipped between them.
 This methodology involves formulas used to
compute the coordinates of the two-dimensional
point that meets the distance and volume criteria
stated above.

26. Plant Location Methodology:
Center of Gravity Method Formulas
C =
d V
V
x
ix i
i


Cx = X coordinate of center of gravity
Cy = Y coordinate of center of gravity
dix = X coordinate of the ith location
diy = Y coordinate of the ith location
Vi = volume of goods moved to or from ith location
C =
d V
V
y
iy i
i



27. Question: What is the best location for a new Z-Mobile
warehouse/temporary storage facility considering only distances
and quantities sold per month?
Plant Location Methodology:
Center of Gravity Method Formulas
 Center of gravity method example
– Several automobile showrooms are located
according to the following grid which represents
coordinate locations for each showroom.
S howroom No ofZ-Mobile s
s old pe r month
A 1250
D 1900
Q 2300
X
Y
A
(100,200)
D
(250,580)
Q
(790,900)
(0,0)

28. Plant Location Methodology: Example of Center of Gravity
Method: Determining Existing Facility Coordinates
S howroom No ofZ-Mobile s
s old pe r month
A 1250
D 1900
Q 2300
X
Y
A
(100,200)
D
(250,580)
Q
(790,900)
(0,0)
To begin, you must identify the
existing facilities on a two-
dimensional plane or grid and
determine their coordinates.
You must also have the
volume information on the
business activity at the
existing facilities.

29. Plant Location Methodology: Example of Center of Gravity
Method: Determining the Coordinates of the New Facility
C =
100(1250) + 250(1900) + 790(2300)
1250 + 1900 + 2300
=
2,417,000
5,450
=
x 443.49
C =
200(1250) + 580(1900) + 900(2300)
1250 + 1900 + 2300
=
3,422,000
5,450
=
y 627.89
Showroom No ofZ-Mobile s
sold pe r month
A 1250
D 1900
Q 2300
X
Y
A
(100,200)
D
(250,580)
Q
(790,900)
(0,0)
You then compute the new coordinates using the formulas:
Z New
location

30. Revise Previous lectures
1. What is plant location?
2. What is an ideal/best location?
3. List principal factors must be considered
selecting a suitable plant site.
4. What are the steps of location Rating Factor?
30

31. Plant layout
 “It is a plan of, or the act of planning, an optimum
arrangement of industrial facilities; including personnel,
operating equipment, storage space, material handling
equipment, and all other supporting services, along with
the design of the best structure to contain these
facilities.”
James M. Moore
 Plant layout is the most effective arrangement and
coordination of the physical plant facilities to allow
greatest efficiency in the combination of men, materials
and machines necessary for operation of any unit of a
plant or business 31

32. • Plant layout refers to the arrangement of physical
facilities such as machines, equipment, tools,
furniture etc.
• In such a manner so as to have quickest flow of
material at the lowest cost and with the least amount
of handling in processing the product from the receipt
of raw material to the delivery of the final product.
• The layout design affects the cost of producing goods
and delivering services for many years into the future
32

33. In Class Exercise:
 Taking the definition of plant layout in to
consideration, if you are asked to design layout
what major principles you will follow?
33

34. PRINCIPLES OF PLANT LAYOUT
1. Principle of overall integration. The layout is best
which integrates(compromise) the men, material,
machinery, supporting activities and any other
considerations.
2. Principle of minimum distance moved. By placing
subsequent operations adjacent to each other, saving
can be made reducing the distance of these moves.
3. Principle of flow. It means that material will move
progressing from one operation to the next towards
completion
4. Principle of cubic space. Economy is obtained by
using effectively all available space both vertical and
horizontal.
5. Principle of satisfaction and safety. It means that
layout is best which makes work satisfying and easy for
workers.
34

35. PRINCIPLES OF PLANT LAYOUT CONT’D
6. Principle of Flexibility. It means that the best
layout is one which can be adopted and
rearranged at minimum cost with least
inconveniences
7. Principle of expansion. Expand in future without
disturbing the existing layout and production
schedules.
8. Principle of versatility. Layout should be adoptable
to changes in product design, sales requirement and
process improvement.
9. Principle of orderliness. Clean work areas with
suitable equipment for removing scrap, wastes etc.
35

36. The objectives of a good plant layout
1. Integrate the production centers
♣ Integrates (men, materials and machines) in to a
logical, balanced and effective production unit.
♣ It permits the arrangement of the equipment to
provide greater utilization.
♣ It helps to increase the output by shortening the
manufacturing time.
2. Reduce material handling. The equipment may be arranged
in such a manner to minimize material handling and
transportation.
36

37. The objectives of a good plant layout …(cont)
3. Effective utilization of available space. The
layout determines the location of departments and
production centers, their proximity to each other to
various services, and hence the efficient utilization of the
available space. More over, a good layout utilizes space,
both vertical and horizontal in the best possible manner.
4. Worker convenience and job satisfaction.
Ergonomics? human factor engineering
Working places-safe, well ventilated and free from dust,
noise, fumes, odor, and other hazardous conditions helps to
increase the efficiency of the workers and improve their
morale.
37

38. The objectives of a good plant layout …(cont)
5. Flexibility.
• The best layout is one, which can be adopted and re-
arranged at a minimum cost with least inconvenience.
6. Avoid unnecessary capital investment. Capital investment
in equipment can sometimes be reduced by the proper
arrangement of machines and departments.
7. Stimulate effective labor utilization. Every year millions of
productive man-hours are wasted because of poor layout.
Proper layout does not guarantee, but certainly stimulates,
the effective utilization of manpower.
38

39. Types of plant layout
Plant layout can be classified as:
1. Process or functional layout
2. Product or line layout
3. Mixed or combined layout
4. Fixed position layout
5. Group technology layout
39

40. 1. Process (Job Shop) Layouts
♣ Equipment that perform similar processes are
grouped together. e.g., all lathes, milling
machines, etc. are grouped in the shop will be
clustered in like groups.
♣ Used when the operations system must handle a
wide variety of products in relatively small
volumes (i.e., flexibility is necessary)
40

41. 41

42. Characteristics of Process Layouts
♣ General-purpose equipment is used
♣ Changeover is rapid
♣ Material flow is intermittent
♣ Material handling equipment is flexible
♣ Operators are highly skilled
♣ Technical supervision is required
♣ Planning, scheduling and controlling functions are
challenging
♣ Production time is relatively long
♣ In-process inventory is relatively high
42

43. 2. Product (Assembly Line) Layouts
♣ Operations are arranged in the sequence required to make
the product.
♣ Used when the operations system must handle a narrow
variety of products in relatively high volumes.
♣ Operations and personnel are dedicated to producing one or
a small number of products.
43

44. Characteristics of Product Layouts
♣ Special-purpose equipment are used
♣ Changeover is expensive and lengthy
♣ Material flow approaches continuous
♣ Material handling equipment is fixed
♣ Operators need not be as skilled
♣ Little direct supervision is required
♣ Planning, scheduling and controlling functions are
relatively straight-forward
♣ Production time for a unit is relatively short
♣ In-process inventory is relatively low
44

45. 3. Mixed or combined layout
♣ Pure process or pure line layouts are rare.
The combination of these is very commonly
used in industry.
♣ The combined layout incorporates the
benefits of the process and product layout.
45

46. Combined layout
Receiving
Raw mat. Fabrication
storage line-part B
Fabrication Planer
line-part A
Finished Lathe
goods Drill
storage Mill
Mill
Drill
Grinder
Mill
Assembly line Automatic
46
Small number of
high volume
products

47. 4. Static or fixed position layout
47
 Is adopted when work piece is
very big or too heavy to move
from one position to the other
and is consequently fixed in one
place.

48. Static or Fixed Position Layout
48

49. 5. Group technology(Cellular)
layout
 Production volumes for individual products
are not sufficient to justify product layouts.
 Grouping products into logical product
families, a product layout can be justified
for the family.
49

50. Group technology layout cont’d
 “Group technology is the technique of
identifying and bringing together related or
similar parts in a production process in order to
utilize the inherent economy of flow
production methods.”
 Group Technology layout is also called
manufacturing cell layout.
 The arrangement of a facility so that
equipment used to make similar parts or
families of parts is grouped together.
50

51. Group technology layout…(cont)
Example:
 A plant producing 10,000 part numbers may be able to
group the parts into 50 or 60 families. Each family
would possess similar design and manufacturing
characteristics.
 Hence, the processing of each member of a given
family would be similar, and this results in
manufacturing efficiencies in the form of:
 Reduced set-up,
 Lower in-process inventories,
 Better scheduling,
 Improved tool control,
 Standard process plan.
51

52. Parts Families
52

53. Group Technology
53
Drilling
D D
D D
Grinding
G G
G G
G G
Milling
M M
M M
M M
Assembly
A A
A A
Lathing
Receiving and
shipping
L
L L
L L
L L
L
(a) Jumbled flows in a job shop without GT cells

54. Group technology layout…(cont)
54
Cell 3
L M G G
Cell 1 Cell 2
Assembly
area
A A
L M D
L
L M
Shipping
D
Receiving
G

55. Class of layout Problems
 Building new plant
 Move to existing plant
 Rearrange existing layout
 Minor changes
55

56. Common Reasons for the design of Layouts
 Changes In Design of Products/services
 Introduction of New Products/services
 Market Demand change
 Changes In Technology/equipment
 Poor Worker environment
 Market Relocation
 Cost Reduction
56

57. 57

58. Introduction
to Ergonomics
58

59. Work’ Cycle
I go to work
To earn the money
To buy the bread
To gain the strength
To go to work
(Courtesy of E. Kamon, 1973)
59

60. What is Ergonomics???
Common Definition
60

61. What is Ergonomics???
61

62. What is Ergonomics???
• Ergonomics is concerned with the interaction
between human and technology
• Ergonomics integrates knowledge delivered
from the human science to match systems,
environments, jobs, and products to the
physical and mental abilities and limitation of
people
62

63.  Ergonomics is the study of the man in relation
to his work
 Sometimes it is called by the name ‘human
engineering or human factors engineering”
 “The application of human biological sciences
along with engineering sciences to achieve
optimum mutual adjustment of men and his
work.
 The benefits being measured in terms of
human efficiency and well-being.”
63
Ergonomics

64. Human engineering (ergonomics) has two
broader objectives:
1.To enhance the efficiency and effectiveness
with which the activities (work) is carried out so
as to increase the convenience of use, reduced
errors and increase in productivity.
2.To enhance certain desirable human values
including safety reduced stress and fatigue and
improved quality of life.
64
Objectives of Human Engineering

65.  Ergonomics aims at providing comfort and
improved working conditions so as to
channelize the energy, skills of the workers
into constructive productive work.
 This accounts for increased productivity,
safety and reduces the fatigue.
65
Cont.…

66. 66
Ergonomic
• Ergonomics, also known as human engineering or human
factors engineering, the science of designing machines,
products, and systems to maximize the safety, comfort,
and efficiency of the people who use them.
• Ergonomists draw on the principles of industrial
engineering, psychology, anthropometry (the science of
human measurement), and biomechanics (the study of
muscular activity) to adapt the design of products and
workplaces to people’s sizes and shapes and their physical
strengths and limitations.

67. Ergonomic
• Ergonomists also consider the speed with
which humans react and how they
process information, and their capacities
for dealing with psychological factors,
such as stress or isolation.
67

68. 68
Ergonomic
• Ergonomist view people and the objects they use
as one unit, and ergonomic design blends the best
abilities of people and machines.
• Humans are not as strong as machines, nor can
they calculate as quickly and accurately as
computers.
• Unlike machines, humans need to sleep, and they
are subject to illness, accidents, or making
mistakes when working without adequate rest.

69. Ergonomic
• But machines are also limited—cars cannot repair
themselves, computers do not speak or hear as
well as people do, and machines cannot adapt to
unexpected situations as well as humans.
• An ergonomically designed system provides
optimum performance because it takes advantage
of the strengths and weaknesses of both its
human and machine components. 69

70. 70
Definition: Ergonomic
IEA (International Ergonomics Association)
”the scientific discipline concerned with the
understanding of the interactions among
human and other elements of a system, and
the profession that applies theory, principles,
data and methods to design in order to
optimize human well-being and overall system
performance”

71. 71
Typical losses from failure to apply
ergonomic
1. Lower production output
2. Increased lost time
3. Higher medical & material cost
4. Increased absenteeism
5. Low quality work
6. Injuries, strains
7. Increased probability of accidents & errors

72. Introduction
Safety, hazard and risk are frequently-used terms in chemical process safety
Definitions
• Safety or loss prevention: the prevention of accidents through the use of
appropriate technologies to identify the hazards of a chemical plant and
eliminate them before an accident occurs.
– Loss Prevention: Prevention of injury to people, damage to
environment, loss of equipment, inventory or production
– Safety : Strategy of accident prevention
• Hazard: a chemical or physical condition that has the potential to cause
damage to people, property, or the environment.
• Risk: a measure of human injury, environmental damage, or economic loss
in terms of both the incident likelihood and the magnitude of the loss or
injury.
72

73. Introduction
Chemical plants contain a large variety of hazards:
1. There are the usual mechanical hazards that cause worker
injuries from tripping, falling, or moving equipment.
2. There are chemical hazards. These include fire and
explosion hazards, reactivity hazards, and toxic hazards.
73

74. Introduction
As will be shown later,
chemical plants are the safest
of all manufacturing facilities.
However, the potential always
exists for an accident of
terrible proportions.
Despite substantial safety
programs by the chemical
industry, headlines of the type
shown in Figure 1-1 continue
to appear in the newspapers.
74

75. Safety Programs
A successful safety program requires several ingredients.
These ingredients are:
• System
• Attitude
• Fundamentals
• Experience
• Time
• You
75

76. Safety Programs
• Why the program needs a System:
1. to record what needs to be done
2. to do what needs to be done
3. to record that the required tasks are done
• Attitude: positive attitude
willingness to do some of the thankless work that is required for success
• Experience: Everyone must learn from the experience of history; read and
• understand case histories of past experience
• Time: Every one should recognize that safety takes time; this include
1. time to study 2. time to do the work
3. time to record results 4. time to share experience
76

77. The most effective means of implementing a safety program is to make it
everyone’s responsibility in a chemical process plant
Distinction between a good and an outstanding safety program
- A good safety program identifies and eliminates
existing safety hazard
- An outstanding safety program has management systems to prevent the
existence of a safety hazard
Most Importantly!! Safety cannot be
Prioritized - it must be condition
of employment!
77

78. Revise previous class
1. Principles of plant layout
2. Types of plant layout
3. Common Reasons for Redesign of Layouts
4. Class of layout Problems
78

79. Assignment
Read & prepare brief description report about
Type of layouts;
 Process layout
 Product layout
 Combined layout
 Fixed position layout
 Group technology layout
79