KIOT
Plant Layout and Facility Design
Course code: Greg 4181
Target group: 4th year GED
Chapter three
Plant Layout
By: Endashaw Yohannes
Kombolcha/Ethiopia
Dec, 2019
12/26/2019 1

1. Meaning of plant layout
2. Objective of plant layout
3. Symptoms of bad layout
4. Advantages of good plant layout
5. Principles of plant layout
6. Types of layout
7. General flow patterns of plant layout
Outline of chapter three

“Plant layout is a plan of an optimum arrangement of
facilities including
Personnel,
Operating equipment,
Storage space,
Material handling equipment and
All other supporting services along with the design
of best structure to contain all these facilities”.
1. Meaning of Plant Layout

2. Objectives of Plant Layout
o The primary goal of the plant layout is to maximize the profit by
arrangement of all the plant facilities to the best advantage of total
manufacturing of the product and at the same time satisfactory and
safe for the personnel doing the work.

2. Objectives of Plant Layout cont...
o Helps for the personnel doing the work.
In the Sense of Unity
o The feeling of being a unit pursuing the same objective.
Minimum Movement of people, material and resources.
Safety
o In the movement of materials and personnel work flow.
Flexibility
o In designing the plant layout taking into account the
changes over short and medium terms in the production
process and manufacturing volumes.

2. Objectives of Plant Layout cont...
• These main objectives are reached through the
attainment of the following facts:
Congestion reduction.
Elimination of unnecessary occupied areas.
Reduction of administrative and indirect work.
Improvement on control and supervision.
Better adjustment to changing conditions.
Better utilization of the workforce, equipment and
services.

2. Objectives of Plant Layout cont...
Reduction of material handling activities and stock in
process.
Reduction on parts and quality risks.
Reduction on health risks and increase on workers
safety.
Moral and workers satisfaction increase.
Reduction on delays and manufacturing time, as well
as increase in production capacity.
 All these factors will not be reached simultaneously, so the
best solution will be a balance among them.

Introduction
• To make a decision about layout planning, 4 different questions must
have an answer:
1. Which centers do we have to consider?
2. How much space and capacity is required for each center?
• If there is not enough space, productivity may be reduced.
• Too much space is expensive and may also reduce productivity.
3. How must the space be related with each center?
• Space quantity, shape and the elements of the work center are
related to each other.
4. Where should each center be located at within the facility?
• The allocation of the different centers may affect productivity.

Design problem
Green field/current
state
Location of one
new machine
• Reasons to design production layout:
New products
Changes in demand
Changes in product design
New machines
Bottlenecks
Too large space between work station
Too long transfer times
Production Layout

Layout Design
Layout
Product
Logistics Process

o Re design of production layout
• The reasons for a re-layout are based on 3 types
of changes:
Changes in production volumes.
Changes in processes and technology.
Changes in the product.
• The frequency of the re-layout will depend on the
requirements of the process.

4. Symptoms of bad layout
Symptoms that allow us to detect the need for a re-layout:
Some machines heavily loaded and some idle
Excessive handling by skilled workers
Long production cycles & delays on delivery
Crowded condition & Poor utilization of available space
Bottleneck in production & obstacles in material flow
Excessive fatigue on workers & frequent accidents
Excessive temporary storage & Backtracking
Difficult in supervision and control
Idle machines and manpower

Figure: improper production layout

3. Advantages of good plant layout
Reduce internal transport to a minimum
Minimizes accidents operations
Makes supervision & production control easier
Makes maintenance and repair easier
Reduces labor turnover
Reduces production delay
Maintain floor area neat and clean
Reduces waste effort, wastages and spoiled work
Reduces back tracking and bottlenecks
Better utilization of manpower and machinery
Possible to improve production methods

•Any layout should satisfy the objective or principles of plant
layout for proper functioning.
•There are Nine basic principles of best plant layout
1. Principle of overall integration
2. Principle of minimum distance moved
3. Principle of flow
4. Principle of cubic space
5. Principle of satisfaction and safety
6. Principle of flexibility
7. Principle of expansion
8. Principle of versatility
9. Principle of orderliness
5. Principles of plant layout

Basic principles of plant layout
1. Principle of overall integration
o The layout is best which integrates
Men,
Material,
Machinery, and
Supporting activities in a way that results best
compromise.
o It must be convenient for people servicing or
supporting the operation as well.

2) Principle of minimum distance moved
Other things being equal the layout is best which
permits the material to move the minimum distance
between operations.
By placing subsequent operations adjacent to each
other reducing the we can reduce distance of
movement .

3) Principles of flow
Other things being equal, the layout is best which
arranges the work area for each operation or process
in the same order or sequence that forms , treats, or
assembles the materials.
It means that material will move progressing from
one operation to the next towards its completion.
Congestion with other parts or other pieces of the
same part is at minimum.

4) Principle of cubic space
• Other things being equal, the best layout utilizes
effectively all available space both vertical and
horizontal.
• Movement of material, men and machinery may be in
any of the three direction.
• It means taking vacant overhead space or work
surface under the floor.

5) Principle of satisfaction and safety
Being other things equal, the layout is best which
makes work satisfying and safe for workers.
Safety is the major factor in most layouts.
A layout can not be good if it subjects employees to
hazardous or accidents.

6) Principle of flexibility
Other things being equal, the layout is best which can
be adjusted and rearranged at minimum cost and
inconvenience.
This objective become more important ,as new
developments are taking place in scientific research
for frequent changes in product design, equipment
and production methods.
Economy can be obtained if a new layout can be made
quickly and inexpensively.

7) Principle of expansion
• It should be easy to expand with out disturbing the
existing layout and production schedules
8) Principle of Versatility
• Layout should be adaptable to changes in product
design, sales requirement and process improvement
9) Principle of orderliness
• Clean work areas with suitable equipment for
removing scrap waste etc.

6. Types of layout
For the purpose of production Men, Machines and
Materials are required.
Men work on materials with the aid of machinery and
tools.
For Production at least on one of them has to be moved.
Production machinery can be grouped and arranged in
different ways.
The ways and arrangement of production machinery
decides the types of layout

Types of layout cont..
• Common types or methods of layout are:
A. Product or line layout
B. Process or functional layout
C. Fixed position lay out
D. Combinations (group layout)
E. Cellular Manufacturing (CM) Layout

The arrangement of equipment is based on the
sequence of operations in the manufacture of an individual
product
or
a group of similar products requiring the same manufacturing
equipment in the same manufacturing sequence.
Only one or one type of product is in operating area.
The product must be standardized and manufactured in
large quantities.
Very popular in mass production ready made garment
factory
A. Product layout

Plant layout example Product Layout

Materials handling is automated, hence reduction in
materials handling cost.
Bottlenecks in production line could be avoided.
Lesser manufacturing time.
The layout helps in better production control.
It necessitates less floor space per unit of production.
WIP is reduced and investment there on is minimized.
Product layout Advantages

Expensive and inflexible layout.
Supervision is difficult.
Expansion is difficult.
Breakdown of any machinery in a line could disturb the
whole system.
A single operator absenteeism in a line could disturb the
whole system.
Product layout disadvantages

Similar equipment and similar operations are grouped
together
Useful where product is not standardized and low
volume is required
It has greater flexibility
Advantageous when products of dissimilar types being
manufactured.
B. Process layout

Plant layout example Process Layout

Better supervision is achievable through specialization.
Investments on machines are reduced as they are general
purpose machines.
There is greater flexibility in the production.
This layout provides better use of men and machines.
It is easier to handle any breakdown of machines through
taking the machine to another machine station.
The investment costs on machines are comparatively lower.
Process layout Advantages

Process layout disadvantages
Movement of materials is difficult.
Requires more floor space.
Since the work-in-progress has to move from one place
to another to look for a machine, the production time is
generally high.
The WIP accumulates at different places.

The material and or major component ,remains in a
fixed location and tools, machinery and men and other
pieces of material brought to this location.
Useful if the product is Extremely large or heavy (
like air craft and ship building ) and extremely low
volume of output (like housing industries)
High skill is demanded
Very common before industrial revolution
C. Fixed position layout

Permits the plant to elevate skill of operators
Less material movement
Greater flexibility allows frequent changes in product
design, product mix and production volume of demand.
Layout capital investment is low.
Men and machines can be utilized for numerous kinds
of operations manufacturing different products.
The costs of transportation for a bulky product are
avoided.
Fixed position layout Advantages

Highly skilled man power is required
Movements of machines and equipments to production
centre may be time consuming
Complicated fixtures may be required for positioning
of jobs and tools. This may increase cost of
production.
Fixed position layout disadvantages

• Combined layouts makes the strong points of
 product,
 process ,and
 fixed position layouts.
o Now a days pure state of any one form of layout is
rare.
o If the good features of all types of layout are
connected a compromise solution can be obtained
which will be more economical and flexible
D. Combined ( Group) lay outs

PRODUCTION VOLUME AND PRODUCT VARIETY
DETERMINES TYPE OF LAYOUT
Group layout process layout
Product variety
Production
volume
product
layout
Fixed
Position
Layouts

E. CELLULAR MANUFACTURING (CM) LAYOUT
In this kind of layout, the machines are generally
assembled into cells which function fairly like a product
layout within a process layout.
Every cell in this design is shaped to produce single
parts, all with common attributes, which typically means
they necessitate the same machines and have similar
machine settings (Ramesh Babu 2006).

Plant layout example Cellular Layout

E. CELLULAR MANUFACTURING (CM) LAYOUT
A. Advantages:
Lower WIP inventories.
Reduced material handling costs.
Flow time of materials is less in production planning.
Improved visual control of process which enables
quicker set ups.
Manufacturing flexibility.
Reduced machine stoppage time.

7. GENERAL FLOW PATTERNS OF PLANT LAYOUT
"Flow Pattern" means the system to be adopted for
the movement of raw materials, from the beginning and
up to the end of manufacturing.
The overall-objective of the Flow pattern is to plan for
the economical movement of the raw materials
throughout the plant.

7. GENERAL FLOW PATTERNS CONT..
Quite often layout design starts with the flow system and
building design are modified accordingly but sometimes the
flow must be adopted to existing buildings.
Most common error in material flow is
o Back-hauling or the back-tracking of materials,
which means that
once the material has passed through an operation it must
maintain its direction and does not retrace its path.

7.1. FLOW SYSTEMS OF PLANT LAYOUT
Based on the flow systems plant layout can be
classified into two:
1. Horizontal layout and
2. Vertical layout.
The horizontal flow system is adopted on a shop floor
Vertical flow is adopted where material has to move in
a multi-store building.

1. HORIZONTAL FLOW LINES
There are five basic types of horizontal flow
line:
A. I-Flow or Line Flow horizontal flow lines
B. L-Flow horizontal flow lines
C. U-Flow horizontal flow lines
D. S-Flow horizontal flow lines
E. O-Flow horizontal flow lines

A. I-FLOW or LINE FLOW HORIZONTAL FLOW LINES
It is the simplest form of flow.
In this, materials are fed at one end and components
leave the line at the other end.
This type is economical in space and convenient in I-
shaped buildings.

B. L-FLOW HORIZONTAL FLOW LINES
It is similar to the I-Flow and is used where I-line
cannot be accommodated in the available space
Figure: L- flow horizontal flow line

C. U-FLOW HORIZONTAL FLOW LINES
In this, both feeding and output take place at the same end,
i.e., it allows both receiving and dispatching of goods to be
done at 'one side.
In comparison to I or L-Flow, this method is easier for
supervision.
Figure: U-Flow horizontal flow lines

D. S-FLOW HORIZONTAL FLOW LINES
I f the production line is so long that zigzagging on the
plant floor is" necessary this S-flow is adopted.
This type provides efficient utilization of space and is
compact enough to allow effective supervision.
Figure: S-Flow horizontal flow lines

E. O-FLOW HORIZONTAL FLOW LINES
This type is used where process or operations are performed
on- a rotary table or a rotary handling system.
The components are moved from one working station to the
other and when they leave the O-line, a complete set of
processes or operations have been performed.
The components inspected before they are moved on to a
second line for an additional series of process- or operations
or to an assembly line.
Figure: O-Flow horizontal flow lines

COMBINATIONS OF BASIC HORIZONTAL FLOW
These above mentioned basic flow lines are mostly used
by industries in various combinations.
Figure: Combinations of basic horizontal flow

I. UNIDIRECTIONAL FLOW
When the material is passed from one to another
without having to pass along the same path
Figure: Combinations of basic horizontal flow

II. RETRACTION FLOW. (REPEATED FLOW )
In this type, the flow is repeated i.e. two or more non-
consecutive operations are performed on the same machine.
In this flow, the available machine time is fully utilized but
schedules have to allow for repeated machine setting-
e.g., each time a machine is switched over from one operation
to another.
Figure: Retraction Flow. (Repeated flow )

2. VERTICAL FLOW LINES
This type of flow is for multi-storey buildings. So that
the materials handling systems and control mechanisms
operate effectively,
Figure: Vertical Flow lines

2. VERTICAL FLOW LINES CONT...
Figure: Vertical Flow lines

Reading
Plant lay out and material handling
(R.B Choudary)
1) Chapter Two – Introduction to plant
layout

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