PLANT LAYOUT

2. PLANT LAYOUT
Plant layout refers to the arrangement of physical
facilities such as machinery, equipment, furniture etc.
with in the factory building 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 material to the shipment
of the finished product.

3. DEFINITION
According to Riggs, “the overall objective of plant
layout is to design a physical arrangement that most
economically meets the required output – quantity
and quality.”
 According to J. L. Zundi, “Plant layout ideally
involves allocation of space and arrangement of
equipment in such a manner that overall operating
costs are minimized.

4. DETERMINENTS OF PLANT LAYOUT
1. TYPE OF PRODUCT (size, shape and quality)
2. TYPE OF PROCESS (technology employed,
sequencing etc)
3. VOLUME OF PRODUCTIONS- (INCREASE OR
DECREASE)

5. IMPORTANCE OF PLANT LAYOUT
• It is long-term commitment
• It facilitates the production process, minimizes material
handling, time and cost, and allows flexibility of
operations
• It facilitates easy production flow, makes economic use of
the building, promotes effective utilization of manpower,
and provides for employee’s convenience, safety, comfort
at work, maximum exposure to natural light and
ventilation.
• it affects the flow of material and processes, labour
efficiency, supervision and control, use of space and
expansion possibilities .

6. OBJECTIVES OF PLANT LAYOUT
• Proper and efficient utilization of available floor space
• To ensure that work proceeds from one point to another point without any
delay
• Provide enough production capacity
• Reduce material handling costs
• Reduce hazards to personnel
• Utilize labour efficiently
• Increase employee morale
• Reduce accidents
• Provide ease of supervision and control
• Provide employee safety and health
• Allow ease of maintenance
• Allow high machine or equipment utilization
• Improve productivity
• To minimize cost of productions
• Better inter department relationship

7. FACTORS INFLUENCING PLANT
LAYOUT
1. Factory building :- The nature and size of the
building determines the floor space available for
layout. While designing the special requirements,
e.g. air conditioning, dust control, humidity control
etc. must be kept in mind.
2. Nature of product :- Product layout is suitable for
uniform products whereas process layout is more
appropriate for custom-made products.

8. 3. Production process :- In assembly line industries,
product layout is better. In job order or intermittent
manufacturing on the other hand, process layout is
desirable.
4. Type of machinery: General purpose machines are
often arranged as per process layout while special
purpose machines are arranged according to product
layout.
5. Repairs and maintenance :- Machines should be so
arranged that adequate space is available between
them for movement of equipment and people
required for repairing the machines.

9. 6. Human needs :- Adequate arrangement should be
made for cloakroom, washroom, lockers, drinking
water, toilets and other employee facilities, proper
provision should be made for disposal of effluents, if
any.
7. Plant environment :- Heat, light, noise, ventilation
and other aspects should be duly considered, e.g.
paint shops and plating section should be located in
another hall so that dangerous fumes can be removed
through proper ventilation etc. Adequate safety
arrangement should also be made.
8. Management policies :- management policies
regarding size, quality, employee facilities and
delivery schedules should be considered while
deciding plant layout.

10. DYNAMICS OF PLANT LAYOUT
Increase in the output of the existing product
Introduction of a new product and diversification
Technological advancements in machinery, material,
processes, product design, fuel etc.
Deficiencies in the layout unnoticed by the layout
engineer in the beginning.

11. PRINCIPLES OF PLANT LAYOUT
• PRINCIPLE OF MINIMUM MOVEMENT
• PRINCIPLE OF FLOW
• PRINCIPLE OF SPACE
• PRINCIPLE OF SAFETY
• PRINCIPLE OF FLEXIBILITY
• PRINCIPLE OF INTERDEPENDENCE
• PRINCIPLE OF OVERALL INTEGRATION
• PRINCIPLE OF MINIMUM INVESTMENT

12. 1. PRINCIPLE OF MINIMUM
MOVEMENT
As far as possible materials and labour should be
moved over minimum distances.

13. 2. PRINCIPLE OF FLOW
The work areas should be arranged according to the
sequence of operations so that there is continuous
flow of materials without congestion.
The layout should allow for easy movement of
materials without interruption or delay.

14. 3. PRINCIPLE OF SPACE
All available cubic space should be effectively used
both vertically and horizontally.

15. 4. PRINCIPLE OF SAFETY
There should be consideration for safety and
convenience of workers.
There should be built in provision for the safety and
comfort.

16. 5. PRINCIPLE OF FLEXIBILITY
Layout should be designed in the manner that
production facilities can easily be rearranged when it
becomes necessary in future on account of expansion
and technological advancement.

17. 6. PRINCIPLE OF
INTERDEPENDENCE
Interdependent operations and processes should be
located in close proximity to each other.

18. 7.PRINCIPLE OF OVERALL
INTEGRATION
All the plant facilities and services should be fully
integrated into a single operating unit so as to
maximize efficiency and minimize costs of
production.

19. 8. PRINCIPLE OF MINIMUM
INVESTMENT
The layout should yield savings in fixed capital
investment through optimum utilization of available
facilities.

20. TYPES OF LAYOUTS
1. PRODUCT OR LINE LAYOUT
2. PROCESS OR FUNCTIONAL LAYOUT
3. FIXED POSITION OR LOCATION LAYOUT
4. COMBINED OR GROUP LAYOUT

21. 1.PRODUCT OR LINE LAYOUT
Under this, machines and equipments are arranged in
one line depending upon the sequence of operations
required for the product. The materials move from
one workstation to another sequentially without any
backtracking or deviation. Under this, machines are
grouped in one sequence. Therefore materials are fed
into the first machine and finished goods travel
automatically from machine to machine, the output
of one machine becoming input of the next.

22. e.g. in a paper mill, bamboos are fed into the
machine at one end and paper comes out at the other
end. The raw material moves very fast from one
workstation to other stations with a minimum work
in progress storage and material handling.
The grouping of machines should be done keeping in
mind the following general principles.
a)All the machine tools or other items of equipments
must be placed at the point demanded by the
sequence of operations.
b)There should no points where one line crossed
another line.
c)All the operations including assembly, testing,
packing must be included in the line

25. ADVANTAGES OF PRODUCT
LAYOUT
1. Low cost of material handling, due to straight and short
route and absence of backtracking.
2. Smooth and uninterrupted operations
3. Continuous flow of work
4. Lesser investment in inventory and work in progress
5. Optimum use of floor space
6. Shorter processing time or quicker output
7. Less congestion of work in the process
8. Simple and effective inspection of work and simplified
production control
9. Lower cost of manufacturing per unit

26. DISADVANTAGES OF PRODUCT
LAYOUT
1. High initial capital investment in special purpose
machine
2. Heavy overhead charges
3. Breakdown of one machine will hamper the whole
production process
4. Lesser flexibility as specially laid out for particular
product.

27. SUITABILITY OF PRODUCT
LAYOUT
1. Mass production of standardized products
2. Simple and repetitive manufacturing process
3. Operation time for different process is more or less
equal
4. Reasonably stable demand for the product
5. Continuous supply of materials
Therefore, the manufacturing units involving
continuous manufacturing process, producing few
standardized products continuously on the firm’s own
specifications and in anticipation of sales would prefer
product layout e.g. chemicals, sugar, paper, rubber,
refineries, cement, automobiles, food processing
and electronics etc.

28. 2.PROCESS OR FUNCTIONAL
LAYOUT
In this type of layout machines of a similar type are
arranged together at one place. E.g. Machines performing
drilling operations are arranged in the drilling
department, machines performing casting operations be
grouped in the casting department. Therefore the
machines are installed in the plants, which follow the
process layout.
The work, which has to be done, is allocated to the
machines according to loading schedules with the object
of ensuring that each machine is fully loaded.
Used when the operations system must handle a wide
variety of products in relatively small volumes (i.e.,
flexibility is necessary)

29. The grouping of machines according to the process has
to be done keeping in mind the following principles
–
1. The distance between departments should be as short
as possible for avoiding long distance movement of
materials.
2.The departments should be in sequence of operations
3.The arrangement should be convenient for inspection
and supervision

32. ADVANTAGES OF PROCESS
LAYOUT
1. Lower initial capital investment in machines and
equipments. There is high degree of machine
utilization, as a machine is not blocked for a single
product
2. The overhead costs are relatively low
3. Change in output design and volume can be more
easily adapted to the output of variety of products
4. Breakdown of one machine does not result in
complete work stoppage
5. Supervision can be more effective and specialized
6. There is a greater flexibility of scope for expansion

33. DISADVANTAGES OF PROCESS
LAYOUT
Material handling costs are high due to backtracking
More skilled labour is required resulting in higher
cost.
Time gap or lag in production is higher
Work in progress inventory is high needing greater
storage space
More frequent inspection is needed which results in
costly supervision

34. SUITABILITY OF PROCESS
LAYOUT
Products are not standardized
Quantity produced is small
There are frequent changes in design and style of product
Job shop type of work is done
Machines are very expensive
Thus, process layout or functional layout is suitable for job
order production involving non-repetitive processes and
customer specifications and non-standardized products,
e.g. tailoring, light and heavy engineering products,
made to order furniture industries, jewelry.

35. 3.FIXED POSITION OR
LOCATION LAYOUT
In this type of layout, the major product being
produced is fixed at one location. Equipment labour
and components are moved to that location. All
facilities are brought and arranged around one work
center. This type of layout is not relevant for small
scale entrepreneur.
E.g. - shipbuilding

37. ADAVANTAGES OF FIXED POSITION
LAYOUT
1. It saves time and cost involved on the movement of
work from one workstation to another.
2. The layout is flexible as change in job design and
operation sequence can be easily incorporated.
3. It is more economical when several orders in
different stages of progress are being executed
simultaneously.
4. Adjustments can be made to meet shortage of
materials or absence of workers by changing the
sequence of operations.

38. DISADVANTAGES OF FIXED POSITION
LAYOUT
Production period being very long, capital investment
is very heavy
Very large space is required for storage of material
and equipment near the product.
As several operations are often carried out
simultaneously, there is possibility of confusion and
conflicts among different workgroups.

39. SUITABILITY OF FIXED POSITION LAYOUT
Manufacture of bulky and heavy products such as
locomotives, ships, boilers, generators, wagon
building, aircraft manufacturing, etc.
Construction of building, flyovers, dams.

40. 4.COMBINED OR GROUP
LAYOUT
Certain manufacturing units may require all three
processes namely intermittent process (job shops),
the continuous process (mass production shops) and
the representative process combined process
In most of industries, only a product layout or
process layout or fixed location layout does not exist.
Thus, in manufacturing concerns where several
products are produced in repeated numbers,
Generally, a combination of the product and process
layout or other combination are found in practice.

41. e.g. for industries involving the fabrication of parts
and assembly, fabrication tends to employ the process
layout, while the assembly areas often employ the
product layout.
In soap, manufacturing plant, the machinery
manufacturing soap is arranged on the product line
principle, but ancillary services such as heating, the
manufacturing of glycerin, the power house, the water
treatment plant etc. are arranged on a functional
basis.

42. RECENT TRENDS IN PLANT
LAYOUT
Plant layout is the art and science of bringing to
gather men, materials, methods and supporting
facilities in the form of a given arrangements that
suits individuals industrial activity to have the
benefits of profits maximizations through economy,
efficiency, effectiveness and productivity. The
designing and instilling a layout is the responsibility
of Engineering and planning department. The
process of preparing layout is an art and well as
science.

43. The recent trends in layout are as follows –
1. The use of computerized facilities design:
The various techniques have been
developed and used in layout engineering such as
ALDEP (Automated layout design program),
CORELAP (Computerized relationship layout
planning), CRAFT (computerized related allocation of
facilities technique), CALP (computer Aided layout
planning) etc. These and other programme can save
time and effort in large and complex layout problems.

44. 2. The use of various tools and techniques for
planning the layout –
Templates: It is a pattern which consists of thin plate
of wood or metal which serves as gauge or guide in
mechanical work. A plant layout template is a scaled
representation of physical object in a layout.
Model equipment: Model or three dimensional
models represents machinery installed in a factory. It
is a replica or a miniature prototype of machine and
equipment. These show minor details and can be
mounted on a thick plastic sheet.
 Layout drawing: Layout drawings are the replica of
a factory floor plan showing the space management. It
is blue print which indicates the total square feet
where all the equipment has to be arranged.

45.  Plot plan: Is a miniature of the entire factory
building including the facilities of workers.
 Line balance: is phase of assembly line study that
equally divides then works to be done among
workers so that the total number of employees
required is minimum. OR concepts like linear
programming, dynamic programming and optimal
methods are used to study line balance problem.

46. FACTORY BUILDING
A ideal plant building is the one which is built to
house the most efficient layout that can be provided
for the process involved, and artificially attractive and
of such standard shape and design which is flexible
its use and expansive units construction. The
building ensures functional smoothness of the
operation. It should be strong enough to withstand
damages, vibrations and heavy machines.

47. FACTORS IN DESIGNING IN
FACTORY BUILDING
Adaptability.
Expandability.
Product and equipment.
Employees facilities and services areas.
Materials handling.
Lighting, ventilation and air-conditioning.
Fire protection.
Security and services and maintenance.

48. TYPES OF BUILDINGS
The decision on choosing a suitable type for a
particular firm depends among other things on the
manufacturing process, the area of land, and the cost
of construction. The industrial building can be
grouped under four types –
1. Single storey building
2.High bay and monitor types
3.Multi-storey building
4.Special building

49. Single storey building: The reduced cost of land
and extensive transport facilities have encouraged
single storey buildings in sub-urban areas.
High bay and monitor types: It is a single storey
structures with roof surrounded by a monitor, giving
maximum overhead space. The overhead space may
be used to operate crane and other overhead facilities.
The monitor provides natural ventilation and side
walls with glass provide natural lighting.
Multi-storey building: In big cities costs of land is
high and has no much scope of horizontal expansion
which has given ways to multi-storey.
Special building: these are needed for certain
manufacturing processes. Eg the aircraft industry
needs a building with spans 300 to 500 feet in length.

50. PLANT UTILITIES
Plant utilities refer to such services as lighting,
ventilation, air-conditioning etc. All these deserve due
consideration from operations management as they
contribute to increased efficiency and greater output.
The types of plant facilities and services are as follow:
1. Plant Lighting
2. Ventilation
3. Air-conditioning
4. Industrial Sanitation
5. Noise control
6. Industrial safety

51. A. Plant lighting: Adequate lighting is necessary for a
worker to perform his job with ease and accuracy.
According to all India General Standards a minimum
of 14 to 18 lumens of illuminations is considered
adequate.
Importance of Good illumination:
 Ease of seeing./reduced eye strain,
 Improved quality of work.
 Better utilization of floor space.
 Good housekeeping.
 Fewer accidents.
 Improved employee morale/ better supervision.
 Flexible layout.

52. There are two major source of lighting –
1. Day light
2.Artificial light
1. Day light - It is natural lighting which is received
from the sun.
2. Artificial light – It refers to illumination through
artificial means as bulbs and tubes.
Types of artificial lights are –
a. General lighting - General lighting is provided by
fixtures, luminaries or grid system placed 10 ft above
the work area. The light is provided uniformly over
the whole department in a sufficient intensity to
satisfy the requirement of the general manufacturing
conditions within it.

53. b. Supplementary lighting –
It involves the provision of intense
light at the point of work or in adjacent areas to suit
the worker particular requirement.
TYPES OF LIGHT SOURCES –
1. Filament or incandescent lamps.
2. Discharge lamps or fluorescent lamps.
3. Electro-luminescent lamps, mercury vapor
lamps.

54. B. VENTILATION –
Ventilation is concerned largely with
engineering techniques for controlling air currents
within the plant and for introducing outdoor air in a
pattern and on a scale that is just adequate to
maintain satisfactory air purity.
Importance of ventilation are –
Protection of the health of workers.
Preservation of quality of the product
Meets legal requirement.

55. TYPES OF VENTILATION
1. General ventilation –
To keep the working conditions at acceptable
comforts level.
To keep contaminants in the air within safe limits.
2.General exhaust ventilation –
It is a system for preventing the
contamination of factory air by withdrawing the
contaminant at its source into a duct system for
discharge to the building exterior.

56. SOURCES OF VENTILATION
1. NATURAL VENTILATION
2. MECHANICAL VENTILATION
C. AIR CONDITIONING -
Industrial air-conditioning requires
control over temperatures, humidity, dust, purity and odors.
Objectives of air-conditioning
1. To protect worker’s health.
2. To improve workers comfort level.
3. To secure specified temperature conditions.
4. To improve the quality of products.
5. Product preservations.
6. To reduce maintenance charges.
7. To improve employer-employee relations.

57. D. INDUSTRIAL SANITATION -
Sanitation refers to control of the
spread of infection and other insults to the health of
the employees. Occupational disease caused by the
industrial process leads to employee’s dissatisfaction
and turnover.
OBJECTIVES –
Supply of portable water.
Disposal of waste and effluents.
Provision of food which is free from contamination.
Elimination of insects and rodents.
Provision of personal services.
Good housekeeping.

58. E. NOISE CONTROL -Noise is unwanted and
unpleasant sound.
Elements –
Impairs the hearing of employees.
Results in fatigue and nervousness.
Vibration causes damage to machinery and
equipments.
Bad working environment
Noise control methods –
Control by absorption
Control at source
Control by ear protection

60. BREAK EVEN ANALYSIS
It is easy to understand that decision of site selection
is an economic one. The site that offers least cost of
operations should be the one selected for
implementation. Total operation cost can be classified
in two broad categories.
- Fixed Costs
- Variable Costs.

61. Where Total Cost can be split up into Fixed
Variable Cost ,it is easy to prepare the BEP as it would
facilitate for optimal decisions by taking into account
volume of business
BEP are drawn for different locations to compare the
sites. Fixed Costs, Variable Costs Revenue / Output
are taken into account to do so. Mathematically,
BE Volume: FC /Contribution.

62. FACTOR RATING METHOD
Factor-rating systems are perhaps the most widely used of the
general location techniques because they provide a mechanism to
combine diverse factors in an easy-to-understand format.
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65. BROWN GIBSON METHOD
The Brown–Gibson model is one of the many
techniques for multi-attribute decision making. The
method was developed in 1972 by P. Brown and D.
Gibson. This is one of the few models which
integrates both objective and subjective factors in
decision making.
The Brown–Gibson model can be mathematically
represented as follows –
Mi = Ci X [D X Oi + (1−D) X Si]

66. Where,
M = Measure for an alternative 'i'
C = Critical factor measure which could be either be 0
or 1 for an alternative 'i'
O = Objective factor measure which could be
between 0 and 1 however the sum of all objective
factor measures for different alternatives should add
back to 1
S = Subjective factor measure which could be
between 0 and 1 however the sum of all subjective
factor measures for different alternatives should add
back to 1
D = Objective factor decision weight and this should
be between 0 and 1
We would select the alternative