facilities planning and layout

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Facilities Planning

By: NEHAL ELSAYAR

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To: Dr. / Ashraf S. Youssuf

Agenda

DefinitionsIntroduction Types of facilities layout problems The objectives of facility layoutRequirements of layout strategy

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y gyBasic types of layoutLayout by productLayout by processLayout by fixed material location Which type of layout to useFactors affecting facility layoutLayout design procedureComparative analysis of layout types

Definitions

1. Facilities layout refers to an optimum arrangement of different facilities including man, machine, equipment, material, etc.

2. configuration of work centers and equipment to ensure a smooth and uninterrupted flow of materials and work- in -process through a facility.

3. Layout – the physical location of all the facilities, machines, equipment and staff belonging to an operation

4. Flow – the way in which transformed resources travel through the operation5. plant layout problem is to find the best arrangement of physical facilities to

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p y p g p yprovide an efficient operation.

6. The layout problem may occur in machines, workstations, storage areas and aisles and also in other places such as grocery stores, hospitals, airports, etc.

7. The complexity of the design problem generally requires that a sequential process be used.

8. Developing the layout is an important step it serves to establish the physical relationships between activities.

9. Aim: “to achieve an optimal interface of the facilities, equipment, and personnel that constitute the operations management system.” (Note: Facility layout must be planned simultaneously with product design, process selection, material /people handling, packaging and not down stream.)

layoutFrom: The Oxford Pocket Dictionary of Current English / Date: 2008

lay·out . the way in which the parts of something are arranged or laid out: changing the layout of the ground floor. elaborate HTML layouts. the way in which text or pictures are set out on a page: the layout is uncluttered and the illustrations are helpful

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layout is uncluttered and the illustrations are helpful.the process of setting out material on a page or in a work: doing layout for newspapers and magazines. a thing arranged or set out in a particular way: a model railroad layout. ,a position in which the body is extended, the head upright, the legs held straight and together, and the arms held out to the sides.

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Agenda

DefinitionsIntroduction Types of facilities layout problems The objectives of facility layoutRequirements of layout strategyB i t f l t

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Basic types of layoutLayout by productLayout by processLayout by fixed material location Which type of layout to useFactors affecting facility layoutLayout design procedureComparative analysis of layout types

Introduction (cont’d …1/5)

•• Facilities planningFacilities planning is the process planning new facilities and revising or expanding old facilities– determines how an activity’s tangible fixed assets best support

achieving the activity’s objective•• Facility layoutFacility layout is the process of determining the placement of

departments workgroups workstations machines and stock

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departments, workgroups, workstations, machines, and stock-holding points within a facilitywithin a facility are determined, and requires the following inputs:– Specification of system objectives in terms of output and flexibility– Estimation of product or service demand on the system– Processing requirements in terms of number of operations and

amount of flow between departments and work centers– Space requirements for the elements in the layout– Space availability within the facility itself


Why Facilities Planning?Why Facilities Planning?• 20-50% of the total expenses within manufacturing

are attributed to materials handling– effective facilities planning can reduce the material handling

costs by at least 10-30%

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• To be competitive, very few companies will be able to retain all of their old facilities or layouts– productivity improvements through elimination or reduction

of unnecessary activities– improved health and safety– to conserve & reduce consumption of energy.– must conform to new rules, regulations, and standards– lower the risk of fire, lower maintenance costs, etc.


Facilities Planning ObjectivesFacilities Planning Objectives

• Minimize material handling cost• Minimize overall production time

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Minimize overall production time• Effectively utilize existing space• Provide for employee convenience• Assure workplace safety and comfort• Facilitate the manufacturing process• Facilitate the organizational structure

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Facilities Planning ProcessFacilities Planning ProcessSpecify or update activities

Determine requirements

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Is it feasible toincorporate new activities

on existing site?

Develop & evaluate alternative plans

Determine new facility location

Continuous improvement & maintenance

Select & implement plan

No

Yes


Facilities Planning ActivitiesFacilities Planning Activities

Facilities Planning

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Facilities Location

Facilities Design

Facilities Systems Design

Facility Layout Facility Layout DesignDesign

Handling SystemsHandling SystemsDesignDesign

Processes that Design Products

and Services

Concept Generation

Processes that Produce Products and

Services

Supply Network Design

Process design

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Screening

Preliminary Design

Evaluation and Improvement

Prototyping and final design

Layout and Flow

Process Technology

Job Design

Types of Layout Problems(cont’d…1/2)

The facilities layout can be classified according to:

The type of facility under consideration e.g.Manufacturing plants

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Commercial facilities, e.g., shops, offices, bank etc.Service facilities, e.g., hospitals, post offices etc.Residential facilities, e.g., Houses, apartments etc.Cities, townships.Recreational facilities, e.g., parks, theatres etc.

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Types of Layout Problems(cont’d…2/2)

The facilities layout can be classified according to:

The nature of layout, it can be categorized into 4 types as follows

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types as followsPlanning a completely new facility.Expanding or relocating an existing facility.Rearrangement of existing layout.Minor modifications in present layout.

Objectives of Facility Layout (cont’d…1/2)

• A facility layout problem may have many objectives. In the context of manufacturing plants, minimizing material handling costs is the most common one.

• Other objectives include efficient utilization of– space– labor

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• Eliminate – bottlenecks– waste or redundant movement

• Layout design requires substantial investments of resources• It is not easily changed and therefore involves long term

commitments• It influences the cost and efficiency of short term operations

Objectives of Facility Layout (cont’d…2/2)

• Facilitate– organization structure– communication and interaction between workers– manufacturing process– visual control

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• Minimize – manufacturing cycle time or customer flow time – investment

• Provide – convenience, safety and comfort of the employees– flexibility to adapt to changing conditions

Requirements of layout strategy

A competitive layout strategy must be fully integrated with: • product design and volume (product strategy)• process equipment and capacity (process strategy)• material handling and packaging systems (manufacturing logistics)• quality of work life (human resource strategy)• building and site constraints (location strategy)

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g ( gy)• marketing strategy

Impact of economic layout on operating costIn the 1990s, TACO Industries, a US manufacturer of circulatory pumps for residential and industrial customers regained its ability to compete by re-engineering its facility strategy to be product oriented rather than process. By focusing on products, TACO redesigned its plant layout to match its manufacturing strategies for different products.

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Advantages of a good layout strategy:

• Minimize manufacturing (service) cycle time thereby maximizing throughput of the system.

• Minimize “set up time” of equipment and material handling.O ti l tili ti f l b d F l th i l k i

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• Optimal utilization of labour and space. For example, there is less work in process inventory

• Meet international environmental and safety standards• Facilitate maintenance• Improves worker morale• Can be used by marketing to increase sales

Constraints on layout & Requirements for a good layout

Constraining factors• Product design & volume• Process equipment & capacity• Building & site • Quality of work life

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Quality of work life Requirements for a good layout• an understanding of capacity and space requirements• selection of appropriate material handling equipment• decisions regarding environment and aesthetics• identification and understanding of the requirements for

information flow• identification of the cost of moving ( load x distance) between

the various work areas

Characteristics of a good layout Source

Manufacturing & Back Office Service Operations

Face-to-Face Services

1. Straight-line flow 1. Easily understood service flowpattern

2. Minimal back tracking 2. Proper waiting facilities

3. Predictable production time 3. Easy communication withcustomers

4. Little w.i.p. storage 4. Customer surveillance easily maintained.

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5. Open plant visibility 5. Clear exit and entry points with sufficient check outcapabilities.

6. Controlled bottlenecks 6. Departments and processes layout – controlled visibility.

7. Work stations close 7. Balance between waiting and service area

8. Minimum material movement 8. Minimum walking (load x distance)

9. Only necessary mat. handling 9. Lack of clutter.

10. Flexible response to changing

conditions

10. High sales volume per squarefoot of facility

The facilities layout decision procedure

Volume and variety

Process type

Decision Decision 11

Decision Decision 22Strategic

Project processJobbing processBatch processMass processContinuous process

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Basic layout type

Detailed designof layout

Decision Decision 33

gperformance

objectivesFixed position layoutProcess layoutCell layoutProduct layout

The physical position of all transforming resources

Flow of transformed resources

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The nature of the basic layout types

Basic layout types

Manufacturing process types

Serviceprocess types

Fixedposition layout

Project processes Professionalservices

Project processes

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Functional layout

Cell layout

Product layout

Jobbing processes

Batch processes

Mass processes

Continuous processes

Service shops

Mass services

Elements of Defining LayoutLayout involves the relative positioning of transformed resources

within operations and functions and the allocation of tasks to the resources, which together dictate the flow of transformed resources through the operation or function

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Relative positioning of transforming resources

Allocation of tasks to transforming resources

Flow of transformed resources

Six (6) Types of Layout Strategies

Fixed-position layout - large bulky projects such as ships and buildings

Process-oriented layout - deals with low-volume, high-variety production (“job shop”, intermittent production)

Office layout - positions workers, their equipment, and

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y p , q p ,spaces/offices to provide for movement of information

Retail/service layout - Marketing focus. Allocates shelf space and responds to customer behavior. See also R&H “Servicescapes” discussion and slides on service layout.

Warehousing and Storage layout – trade off space and material handling.

Product-oriented layout - seeks the best personnel and machine use in repetitive or continuous production

Design Techniques

• Fixed position – resource location analysis• Functional layout – flow charts and relationship

charts

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charts• Cell layout – product flow analysis• Product layout – assembly line balancing techniques

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Basic Types of Layout

Volume

High Product Planning Department

P d t

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Medium

LowLow Medium High Variety

Fixed Materials Location Planning Department

Process Planning Department

Product Family Planning Department

Product Layout

Fixed Location Layout

Group Technology Layout

Process Layout

Product variety

Production volume

I. Project or Fixed Position (Product) Layout (cont’d…1/7)

Lathe Press Grind

St

War

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Weld AssemblyPaint

orage

ehouse

Project or Fixed Position (Product) Layout (cont’d…2/7)

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This is the layout for project type systems in which the major component is kept at a fixed position and all other materials, components, tools, machines, workers etc. are brought and assembly or fabrication is carried out.

Thi t f l t i t d l d th

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This type of layouts is now not used very commonly ads the machines required for manufacturing work are big and complicated.

The fixed position layout is used only when it is difficult to move the major component and fabrication is to be carried out e.g. production of ships.

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• Transformed resources remain stationary• Transforming resources move as necessary• Effectiveness is governed by:

• Scheduling of transforming resources (e.g.

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Scheduling of transforming resources (e.g. access to construction site)

• Reliability of transforming resources (e.g. deliveries by different contractors)

• Examples: shipbuilding, construction projects, some surgeries, restaurants, mainframe computer maintenance


Some of the major advantages of fixed position layout are as follows:

i. The handling requirements for major unit are minimized.ii. High adaptability to the variety of product and intermittent demand.

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iii. The responsibility for quality can be pin-pointed.iv. The capital investment is minimum.v. Material movement is reduced.vi. Promotes job enlargement by allowing individuals or teams to

perform the “whole job”.vii. Continuity of operations and responsibility results from team.viii. Highly flexible; can accommodate changes in product design,

product mix, and product volume.ix. Independence of production centers allowing scheduling to achieve

minimum total production time.


Limitations:

i. Increased movement of personnel and equipment.ii. Equipment duplication may occur.

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iii. Higher skill requirements for personnel.iv. General supervision required.v. Cumbersome and costly positioning of material and machinery.vi. Low equipment utilization.


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II. Process or Functional Layout (cont’d…1/8)

Lathe Drill Weld

SWa

Lathe Weld

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Mill

Drill

Grind

torage

arehouse

Lathe

Mill

Mill

Lathe

Mill

Paint

Grind

Assembly

Assembly

Paint

Process or Functional Layout (cont’d…2/8)

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This type of layout is developed for process focused systems.

The processing units are organized by functions into departments on the assumption that, certain skills and

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facilities are available in each department. Similar equipments and operations are grouped together,

e.g., milling, foundry, drilling, planting, heat treatment etc.The use of process-focused systems is very wide both in

manufacturing and other service facilities such as hospitals. Large offices, municipal services etc.


The functional layout is more suited for low-volumes of production (batch production) and particularly when the product is not standardized. It is economical when flexibility is the basic system requirement.

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when flexibility is the basic system requirement.The flexibility may be in terms of the routes through the

system, volume of each other, and the processing requirements of the items.

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• Similar processes (or processes with similar needs) are located together

• Utilisation of transforming resources is improved –convenience of grouping similar processesT f d th h th ti

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• Transformed resources move through the operation according to their needs

• Different products ≡ different needs ≡ different routes• Complex flow pattern in the operation• Examples: supermarkets, some machine

manufacture, hospitals


Advantagesi. Better utilization of machines can result; consequently, fewer machines

are required.ii. A high degree of flexibility exists relative to equipment or man power

allocation for specific tasks.

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allocation for specific tasks.iii. Comparatively low investment in machines is required.iv. The diversity of tasks offers a more interesting and satisfying

occupation for the operator.v. Specialized supervision is possible.vi. Greater incentive to individual worker.vii. More continuity of production in unforeseen conditions like breakdown,

shortages, absenteeism etc.


Limitationsi. Since longer flow lines usually exist, material handling is

more expensive.ii. Production planning and control systems are more

involved.

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involved.iii. Total production time is usually longer.iv. Comparatively large amounts of in-process inventory

result.v. Space and capital are tied up by work in process.vi. Because of the diversity of the jobs in specialized

departments, higher grades of skill are required.


An example of a functional layout in a library showing the path of just one customer

On-line and CD-ROM access room

Loan books in subject order

ToStudy desks

40Entrance Exit

Enqu

iries

Store room

Counter staffCopying area

Com

pany

repo

rts

To journal sack

Current journals

Reserve collection

Reference section

Study desks

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III. Cellular or Group Layout (cont’d…1/12)

Drill Grind Assembly

Weld

St

War

Lathe

AssemblyMill Paint

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Drill

Weld

Assembly

orage

ehouse

Assembly

Grind

Press

Mill

Lathe

Paint

Drill

Drill

Press

Grind

Assembly

Cellular or Group Layout (cont’d…2/12)

It is special type of functional layout on which the facilities are clubbed together into cells.

This is suitable for systems designed to use the concepts, principles and approaches of ‘group technology’, such a layout offers the advantages of

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gy , y gmass production with high degree if flexibility.

we can employ high degree of automation even if the number of products are more with flexible requirements.

In such a system the facilities are grouped into cells which are able to perform similar type of functions for a group of products.


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• Machines or services grouped into cells • Cells determined by the process requirements of the

family of product/services they transform• Could be considered mini product layouts

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• Can simplify a functional/process layout• Flexible• Duplicates some resources• Examples: some computer component manufacture,

department stores, ‘lunch’ products areas in supermarkets, certain units in hospitals

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• Every cell contains a group of machines which are dedicated to the production of a family of parts.

• One of the problems is to identify a family parts that require the same group of machines.

• These layouts are also called as group technology layouts.

Enter

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Enter

Worker 1

Worker 2 Worker 3

Exit

Key: Product routeWorker route

Machines


Advantages i. Increased machine utilization.ii. Team attitude and job enlargement tend to occur.iii. Compromise between product layout and process layout, with associated

advantages.

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giv. Supports the use of general purpose equipment.v. Shorter travel distances and smoother flow lines than for process layout.vi. Reduced material handling and transit timevii. Reduced setup timeviii. Reduced work-in-process inventoryix. Better use of human resourcesx. Better scheduling, easier to control and automate


Limitationsi. General supervision required.ii. Higher skill levels required of employees than for product layout.iii. Compromise between product layout and process layout, with associated

limitations.iv. Depends on balanced material flow through the cell; otherwise, buffers and work-

i t i d

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in-process storage are required.v. Lower machine utilization than for process layout.vi. Sometimes cells may not be formed because of inadequate part families.vii. Some cells may have a high volume of production and others very low. This results

in poorly balanced cells.viii. When volume of production changes, number of workers are adjusted and workers

are reassigned to various cells. To cope with this type of reassignments, workers must be multi-skilled and cross-trained.

ix. Sometimes, machines are duplicated in different cells. This increases capital investment.


The ground floor plan of a department store showing the sports goods shop-within-a-shop

retail ‘cell’

Sports shop Menswear

Books and

videos Footwear

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Women’s clothes

Luggage and gifts

Confectionery, newspaper,

magazines and stationery

Perfume& jewellery

Elevators

Entrance

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The three major types of arrangement in the GT cells are the single-row, multi-rows or loop layout

The single-row layout, or sometimes known as the GT flow line layout, is used when the parts assigned to the group follow the same machine sequence.

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qThe multi-row layout, or the GT cell layout, permits parts to move

from any machine to any other machine. The flow of parts may not be unidirectional in this layout. The GT

centre layout, on the other hand, is based on a functional arrangement of the machines and is suitable when the product-mix changes frequently.


m1 m2 m3 m4 m5m1

m2

m3

m4

m5

m6

50Types of layout in the GT cell

(a) single-row layout (b) multi-row layout

(d) loop layout

robot

m3

m1 m2

m3

m4m5

(c)semi-circular layout

m1 m2m3

m4m5m6

m7

m8


The single row layout may assume different configuration such as semi-circular, linear or U-shaped. The machines in the single row layout are arranged as close as possible to the sequence of operations of all the parts processed in the layout in order to minimize traveling time.

In this layout, the sequence of operations are normally similar from one part to another d h i l h dli i d ll

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and the material handling equipment used are normally conveyors.

The multi-row layout is usually linear and the movements of parts can be between any machines in different rows as well as in the same row, which is suitable for FMS.

In the loop layout, machines are arranged in an oval path with unidirectional movement.


Group Technology (Cellular Layout/Work Cells)

• Conversion of a process focused layout into a miniature version of a product layout to increase productivity.

• Dissimilar machines are grouped together into work cells to perform work to produce goods that can be grouped into families on the basis of common processing requirements, materials, geometrical shape, size, weight, function.

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processing requirements, materials, geometrical shape, size, weight, function. • These cells are temporary and can shrink or expand in size based upon product

demand.• Flexible Manufacturing Systems represent a special case of group technology

by integrating computer aided manufacturing systems and automated material flow using computer controlled machines for a wide range of manufacturing operations.

• Example: production of components for a medical device such as a pace maker. A cell can be assigned to produce and be responsible for inspection of a complete component.

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Cellular or Group Layout (cont’d…)Group Technology (Cellular Layout/Work Cells)

Work Cell Floor Plan

OfficeOfficeSawsSaws DrillsDrills

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Tool RoomTool RoomWork CellWork Cell

Cellular or Group Layout Example (cont’d…1/10)

4 6 7 9

Assembly

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12

1

2

3

5 8

10

11

A B C Raw materials


• The previous slide shows a facility in which three parts A, B, C flow through the machines.

• The next slide provides the information in a matrix form which includes some other parts D, E, F, G, H.

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• The rows correspond to the parts and columns to the machines.

• Just by interchanging rows and columns, eventually a matrix is obtained where the “X” marks are all concentrated near the diagonal. This matrix provides the cells. For example, parts A, D and F require Machines 1, 2, 4, 8 and 10 which forms a cell.


Parts 1 2 3 4 5 6 7 8 9 10 11 12A x x x x xB x x x x

Machines

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C x x xD x x x x xE x x xF x x xG x x x xH x x x

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Parts 1 2 4 3 5 6 7 8 9 10 11 12A x x x x xB x x x x

Machines

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B x x x xC x x xD x x x x xE x x xF x x xG x x x xH x x x


Parts 1 2 4 3 5 6 7 8 9 10 11 12A x x x x xD x x x x x

Machines

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D x x x x xB x x x xC x x xE x x xF x x xG x x x xH x x x



Machines

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B x x x xC x x xE x x xF x x xG x x x xH x x x



Machines

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D x x x x xF x x xB x x x xC x x xE x x xG x x x xH x x x

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Machines

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D x x x x xF x x xB x x x xC x x xE x x xG x x x xH x x x



Machines

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D x x x x xF x x xC x x xG x x x xB x x x xE x x xH x x x


128 910

Assembly

63Each of A, B, C now visits only one area, minimizing jumping

12 3

4

5

6

7

11

A BCRaw materials

Cell1Cell 2 Cell 3

IV. Product or Line Layout (cont’d…1/7)

Drill Grind Drill

Drill

St

War

Ass

Lathe

BendPress

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Lathe

Drill

Drill

orage

ehouse

embly

Bend

Lathe

Mill

Press

Drill

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Product or Line Layout (cont’d…2/7)

This type of layout is developed for product systems.In this type of layout only one product, or one type of

product, is produced in a given area.In a case of product being assembled this type of

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In a case of product being assembled, this type of layout is probably known as an ‘assembly line’.

The work centers are organized in the sequence of appearance.

The raw material enters at one end of the line and goes from one another rapidly with minimum of work-in-process storage and material handling.


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• Sometimes called line layout• Locates the transforming resources entirely for the convenience

of the transformed resources• Transformed resources follow a specified route – the sequence

of activities that are required matches the sequence in which the

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of activities that are required matches the sequence in which the processes have been located

• Flow is clear, predictable, easy to control• Examples: car assembly, paper manufacture, self-service

canteen


A product layout in a paper manufacturing operation

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Advantages i. Since the layout corresponds to the sequence of operations, smooth and logical

flow lines result.ii. Since the work from one process is fed directly into the next, small in-process

inventories result.iii T t l d ti ti it i h t

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iii. Total production time per unit is short.iv. Since the machines are located so as to minimize distances between consecutive

operations, material handling is reduced.v. Little skill is usually required by operators at the production line; hence, training is

simple, short, and inexpensive.vi. Simple production planning control systems are possible.vii. Less space is occupied by work in transit and for temporary storage.


Limitationsi. A breakdown of one machine may lead to a complete stoppage of the line that

follows that machine.ii Since the layout is determined by the product a change in product design may

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ii. Since the layout is determined by the product, a change in product design may require major alternations in the layout.

iii. The “pace” of production is determined by the slowest machine.iv. Supervision is general, rather than specialized.v. Comparatively high investment is required, as identical machines (a few not fully

utilized) are sometimes distributed along the line.

Mixed or hybrid Layout (cont’d…1/2)

Combination of the layouts discussed.A sample hybrid layout that has characteristics of group, process and product layout is shown in the following figure.A combination of group layout in manufacturing cells, product layout in assembly area, and process layout in the general machining and finishing section is used.

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TM

TM TM

TM TMDM

BM

Mixed or Hybrid Layout (cont’d…2/2)

A restaurant complex with all four basic layout types

Fixed-position layout

Cell layout buffet

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Line layout

cafeteria

service restaurant

Cool roomFreezer Vegetable preparation Grill

Preparation

Ove

n

Functional layout kitchen

Main course buffet

Star

ter

buffe

t

Des

sert

bu

ffet

Service line

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Advantages and disadvantages

Fixedpositionlayout

Functionallayout

Celllayout

Productlayout

Very high product and mix flexibility.

P d t/ t

High product and mix flexibility.

R l ti l b t

Can give good compromise.

F t th h t

Low unit costs for high volume.

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Disadvantages

Advantages Product/customer not moved.

High variety of tasks for staff.

Very high unit costs.

Scheduling space and activities can be difficult.

Relatively robust in the case of disruptions.

Easy to supervise.

Low utilization.

Can have very high WIP.

Complex flow.

Fast throughput.

Group work can result in good motivation.

Can be costly to rearrange existing layout.

Can need more plant.

Opportunities for specialization of equipment.

Can have low mix flexibility.

Not very robust to disruption.

Work can be very repetitive.

Which type of layout to use? (cont’d…1/6)

The fixed position layout is used ideally for a project situation i.e. for one product of a different type.

As the quantity increases the production operations can be broken down into different work centers and material can be allowed to move rather than the machines, and a process layout is

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, p ypreferred.

With further increase in volume i.e. with mass production the advantages of production line can be better derived and a product layout is desirable.

The break-even analysis comprise the production volume of the three basic layouts i.e., product, process and fixed position layout.


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Volume – Variety Influence

Fixed-position layout

Process layout

VolumeLow High

Hig

h

Flow is intermittent

re fe

asib

le

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Product layout

Cell layout

Varie

tyLo

w

Regular flow more important

Flow becomes

continuous

Reg

ular

flow

mor

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Which type of layout to use? (cont’d…4/6)Process Type vs. Layout Type

Service functional types

Manufacturing functional types

Basic layout types

Fixed-position layoutProfessional

i

Project processes

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Mass services

Service shops

Continuous processes

Mass processes

Batch processes

Functional layout

Cell layout

Product layout

Jobbing processes

services

Which type of layout to use? (cont’d…5/6)Cost vs. LayoutThe basic layout types have different fixed and variable cost characteristics that seem to

determine which one to use

Cos

ts

78Volume

Use productUsecell

Use functionalUse fixed-

position

Which type of layout to use? Cost vs. Layout (cont’d…6/6)

Cos

ts Fixed-position

Functional

Cell

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Volume

Product

Use fixed-position

Use functionalUse fixed-position or functional

?

Use functional or cell

?

Use functional or cell or product

?

Use cell or product

?Use product

Plant layout factors (cont’d…1/3)

The design of any layout is governed by a number if factors and the best layout is the one that optimizes all the factors.

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As discussed by Muther (1995) the factors influencing any layout are categorized into the following eight groups:

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i. Material factor: includes design, variety, quantity, the necessary operations, and their sequences.

ii. Man factor: includes direct workers, supervision, and service help, safety and manpower utilization.

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p, y piii. Machinery factor: includes the process, producing

equipment and tools and their utilization.iv. Movement factor: includes inter and

intradepartmental transport and handling at the various operations, storage and inspections, the materials handling equipments.


v. Waiting factor: includes permanent and temporary storages and delays and their locations.

vi. Service factor: includes service relating to employee facilities such as parking lot, locker rooms, toilets, waiting rooms etc. service relating to

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, , g gmaterials in terms of quality, production control, scheduling, despatching, waste control; and service relating to machinery such as maintenance.

vii. Building factor: includes outside and inside building features and utility distribution and equipment.

viii. Change factor: includes versatility, flexibility and expansion.

Layout Procedures

Two different categories:

Construction - involves developing a new layout

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“from scratch”

Improvement - generate layout alternatives based on an existing layout

Layout design procedure (cont’d…1/13)

Detailed layout design: What makes a good layout?

• Inherent safety• Length of flow

Cl it f fl

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• Clarity of flow• Staff conditions• Management coordination • Accessibility• Space utilisation• Long-term flexibility

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The overall layout procedure can be considered to be composed of four phases:

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Phase I LocationPhase II General Overall LayoutPhase III Detailed layoutPhase IV Installation


Some important guidelines that help in the layout design are:

i. Plan from whole to detailsii. First plan the ideal and then move to the

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ii. First plan the ideal and then move to the practical aspects

iii. Material requirements should be central to the planning of process and machinery

iv. Modify the process and machinery by different factors to plan the layout


Through there is always an overlap in the different phases of layout design the major steps that have to be followed in the layout design are outlined as follows:

i. Statement of the problem in terms of its objectives, scope and factors to be considered.

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pii. Collection of basic data on sales forecasts,

production volumes, production schedules, part lists, operations to be performed, work measurement, existing layout, building drawings etc.

iii. Analysis of data and its presentation in the form of various charts.

iv. Designing the production process.


v. Planning the material flow pattern and developing the overall material handling plan.

vi. Calculation of equipment requirements and work centers.

vii. Planning of individual work centers.

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gviii. Selection of material handling equipment.ix. Determining storage requirements.x. Designing activity relationships.xi. Planning of auxiliary and service facilities.xii. Calculation of space requirements and allocation of

activity areas.

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xiii. Development of Plot Plan.xiv. Development of Block Plan.xv. Development of detailed layouts in terms of steps

(vii) to (xi)

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(vii) to (xi).xvi. Evaluation, modification and checking of layouts.xvii. Installation of layouts.xviii.Follow up.


Fixed Position

• Design a layout to maximise the effectiveness of the transforming resources

• Resource location

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Resource location• Define site and available locations• Define resource centres and their requirements• Devise evaluation criteria• Match resource centres to available locations• Preliminary allocation on site criteria• Amend allocation using relative-location criteria


Functional Layout

• Complex due to large number of options possible• Flow charts and relationship charts

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• Some of the information requirements• Area required by each work centre• Constraints on the shape of work area allocated• Degree and direction of flow between work areas• Desirability of work centres proximity to each other

or to fixed points in the layout


Cell Layout

• Cells are a compromise between the flexibility of process layout and the simplicity of product layout

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• Design of cell layout requires decisions as to• Extent and nature of cells to adopt – examining

amount and of resources located within the cell• Resources to allocate to cells – cluster analysis /

parts family coding• Production flow analysis

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Product Layout

Decisions required are:• What cycle time is needed?

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What cycle time is needed?• How many stages are needed?• How should the task-time variation be dealt

with?• How should the layout be balanced?• How should the stages be arranged?

Layout design procedure Product Layout (cont’d…11/13)

Cycle time of product layouts• Time between completed products /

services emerging from the operation• Calculated using projected demand for

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• Calculated using projected demand for period and the amount of production time available in that period

• Cycle time = time available /number to be processed


• Number of stages• Requires cycle time and total quantity of work• Number of stages = Total work content /

cycle time

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cycle time• Task time variation

• Variance around the mean for each stage• Balancing work time allocation

• Minimise balancing loss• Balancing Techniques


• Arranging the stages: long thin or short fat• Shape of the line

• Staffing flexibility and balance

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• Rework• Handling• Passage• Teamwork

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Systematic Layout Planning (SLP)

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y y g ( )

SYSTEMATIC FACILITIES SYSTEMATIC FACILITIES PLANNINGPLANNING

SystematicSystematic::Organized,Organized, disciplined rational approach to a disciplined rational approach to a problemproblemFacilitiesFacilities::

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Building,Building, production & material handling production & material handling equipment, land, access (supporting equipment, land, access (supporting equipment)equipment)PlanningPlanning::Decide a course of action based on facts and Decide a course of action based on facts and analysisanalysis

SYSTEMATIC FACILITIES SYSTEMATIC FACILITIES PLANNINGPLANNING

Systematic Facilities Planning fits in this Systematic Facilities Planning fits in this category:category:

Common SenseCommon SenseP i E iP i E i

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Prior ExperiencePrior ExperienceSimple Numerical MethodsSimple Numerical MethodsVisual RepresentationsVisual Representations

Practical PerceptivenessPractical Perceptiveness

Systematic Layout Planning

•• Systematic layout planningSystematic layout planning accounts for the importance of having each department located next to every other department– guided by trial and error– switch departments then check the results of the “closeness”

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– switch departments then check the results of the closeness score

• Why us SLP?– numerical flow of items between departments can be

impractical to obtain, or– interdepartmental flow method does not account for any of

the qualitative factors that may be crucial to the placement decision

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The SLP procedure was presented by Francis and White (1974).

Once the appropriate information is gathered, a flow analysis can be combined with an activity analysis to develop the relationship diagram

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develop the relationship diagram.Space considerations when combined with the

relationship diagram lead to the construction of the space relationship diagram.

Based on the space relationship diagram, modifying considerations and practical limitations, a number of alternative layouts are designed and evaluated.

Systematic Layout Planning procedure

From-To Chart Relationship Chart

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The Phases of Systematic Layout Planning The Phases of Systematic Layout Planning (cont’d …(cont’d …11//22))

I LOCATION

II OVERALL LAYOUT

III DETAIL LAYOUTS

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IV INSTALLATIONTime

NEW BLDG

MFGBLDG

MAINBLDG

HIW

AY

BD

CA

D

Phase I: Phase II: Phase III: Phase IV:

The Phases of Systematic Layout Planning The Phases of Systematic Layout Planning (cont’d …(cont’d …22//22))

f Det

ail

Phase

III

IV

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Time

Leve

l of

I

II

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Muther’s Systematic Layout Planning Procedure (SLP)

1. It uses as its foundation the activity relationship chart.

2. A material flow analysis (from-to-chart) and an activity relationship analysis (activity relationship chart) are performed

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3. Relationship diagram is developed

4. Determine the amount of space to be assigned each activity (use departmental service and area requirement sheets)

5. Space templates are developed for each planning department this leads to the space relationship diagram

6. Layout alternatives are developed

Richard Muther’s Simplified Systematic Layout Planning (1994) (cont’d …1/6)

1. Chart the relationships

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2. Establish space requirements

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3. Diagram activity relationships

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4. Draw space relationship layouts

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5. Evaluate alternative arrangements

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6. Detail the selected layout plan

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Systematic Layout Planning (cont’d …1/3)

A Absolutely NecessaryE Especially ImportantI ImportantO Ordinary Closeness O.K.U UnimportantX Undesirable

A and X > E > I > O > U

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XA

O

E

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113


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Process Layout: Process Layout: Systematic Layout PlanningSystematic Layout PlanningNumerical flow of items between departments Numerical flow of items between departments

Can be impractical to obtainCan be impractical to obtainDoes not account for the qualitative factors that may be Does not account for the qualitative factors that may be crucial to the placement decisioncrucial to the placement decision

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Systematic Layout PlanningSystematic Layout PlanningAccounts for the importance of having each department Accounts for the importance of having each department located next to every other departmentlocated next to every other departmentIs also guided by trial and errorIs also guided by trial and error

Switching departments then checking the results Switching departments then checking the results of the “closeness” score of the “closeness” score

Prevailing Methodology:Systematic Layout Planning (SLP)

1. MaterialFlows

2. ActivityRelationships

3. RELChart

116Departments ≡ Activities

4. RELDiagram

5. SpaceRequirements

6. Space RELDiagram

7. SpaceAvailability

8. LayoutAlternatives

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Systematic Layout Planning is essentially an organized Trial-and-Error Approach.Therefore, unless all possible layouts are considered, There is no way to know if an Optimal Solution been

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y pReached.However, there are a number of Heuristics that can be used to Generate good solutions Quickly.Heuristics: Trial-and-error solutions that do not give optimal solution but easy to apply.


Layout planning Heuristics are of two types:

- Those which start with an initial layout

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and proceed to modify it (These are called Improvement Heuristics), and

- Those which start the Layout analysis from scratch (Construction Heuristics.)


The most widely known algorithm requiring an Initial Layout developed by hand is the Computerized Relative All ti f F iliti T h i

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Allocation of Facilities Technique (CRAFT).CRAFT was developed for situations in which Materials Handling Costs were a major consideration.


Therefore, its goal is to Minimize the Total Cost of Moving Items between Departments.It attempts to improve an Initial Layout by switching the locations of pairs of

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switching the locations of pairs of departments.It begins with one department, AND one by one Analyzes the effect on total travel cost of switching those departments.

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While the Original CRAFT was used only for single-story buildings,An extension of CRAFT called SPACECRAFT

h dl lti t b ildi

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can handle multistory buildings.Some examples of Construction Heuristics include CORELAP (Computerized Relationship Layout Planning) and ALDEP (Automated Layout Design Program).


These heuristics start with an empty floor area and proceed to fit departments

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departments.ALDEP can be used in a multistory building. It generates many alternative layouts.


CORELAP on the other hand, can lay out only single story buildings.

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Both programs use closeness codes defined in the Activity Relationship Charts.

Systematic Layout Planning—Example 1 (cont’d…1/9)Reasons for Closeness

Code

1

2

Reason

Type of customer

E f i i

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2

3

4

5

6

Ease of supervision

Common personnel

Contact necessary

Share same price

Psychology

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Systematic Layout Planning—Example 1(cont’d…2/9)Importance of Closeness

Value

A

E

Closeness Linecode

Numericalweights

Absolutely necessary

Especially important

16

8

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E

I

O

U

X

Especially important

Important

Ordinary closeness OK

Unimportant

Undesirable

8

4

2

0

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Systematic Layout Planning—Example 1(cont’d…3/9)Relating Reasons and Importance

From

1. Credit department

2. Toy department

6I

--U

4A

--U

U1I

1 6A

To2 3 4 5

Area(sq. ft.)

100

400

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3. Wine department

4. Camera department

5. Candy department

-- 1 1,6

--U

1X

1X

300

100

100

Letter

Number

Closeness rating

Reason for rating

Systematic Layout Planning – Example 1Relating Reasons and Importance (cont’d…4/9)

From

1. Credit department

2. Toy department

6I

--U

4A

--U

U1I

1 6A

To2 3 4 5

Area(sq. ft.)

100

400

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3. Wine department

4. Camera department

5. Candy department

-- 1 1,6

--U

1X

1X

300

100

100

Closeness rating

Reason for rating

Note here that the (1) Credit Dept. and (2) Toy Dept. are given a high rating of 6.Letter

Number

Note here that the (2) Toy Dept. and the (5) Candy Dept. are given a high rating of 6.

Systematic Layout Planning—Example 1 (cont’d…5/9)

Initial Relationship DiagramThe Starting SolutionThe Starting Solution

1 3E

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2

4

5

U U

A

I

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Systematic Layout Planning - Example 1Initial Relationship Diagram (cont’d…6/9)

1

4

3

U U

E

I

The number of lines here represent paths

required to be taken in transactions between

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2 5A

transactions between the departments. The

more lines, the more the interaction between

departments. Note here again, Depts. (1) and

(2) are linked together, and Depts. (2) and (5) are linked together by multiple lines or

required transactions.

Systematic Layout Planning - Example 1 Initial Relationship Diagram (cont’d…7/9)

2

3

130

4

1

5

Systematic Layout Planning—Example 1Initial and Final Layouts (cont’d…8/9)

Initial Layout (ignoring space constraints)

2 45

131

13

Systematic Layout Planning – Example 1Initial and Final Layouts (cont’d…9/9)

1

2 4

3

5 2

5 1 43 20 ft

Note in the

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Initial Layout

Ignoring space andbuilding constraints

50 ft

Final Layout

Adjusted by squarefootage and buildingsize

Final Layout that Depts. (1) and (5) are not both placed directly next to Dept. (2).

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Systematic Layout Planning:Systematic Layout Planning: Example Example 22(cont(cont’’d d ……11//33))

A relationshipsE relationshipsI relationships

1 8105

4

133

3 2

6 7

9


Scaled activity relationship diagram

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Systematic Layout Planning:Systematic Layout Planning: Example Example 2 2 (cont(cont’’d d ……33//33))

Alternative layouts

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A small accounting Firm, GUNTAŞ Accounting, has rented Space in a new one-floor building.The firm has allocated 6000 square meter to its seven departments as follows:

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In the first step of Systematic Layout Planning, we analyze interactions between departments AND we assess the desirability of placing departments together.

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The firm has carefully analyzed its operations to Determine the importance of Locating specific departments Close Together.The results of this analysis are summarized in the following Activity Relationship Chart:


138


139


140

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This Activity Relationship Diagram is essentially an Illustration of the Information Contained in the Activity Relationship Chart

141

Relationship Chart.All departments in this diagram are Represented by equal size boxes.The next step is to anticipate the space required for each Department.


Since the space assignments are given before, the following Activity Relationship Diagram shows the relative Sizes of Each Department:

142


In this stage, there are no restrictions on the length and width of each departmentIn the final step, we should develop and

143

In the final step, we should develop and evaluate several alternative layouts, while keeping in mind the Practical Limitations.


Some examples of Practical Limitations in this case were as follows:1- It is considered that offices for partners (2) th ti (7) d th ti

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(2), the meeting room (7) and the reception area (1) should be close to each other.2- It is important that the juniors (4) and the managers (3) be close together.

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As a result of these limitations, An alternative floor plan is developed as follows:

145


This floor plan may be revised many times until the best layout has been found.

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the best layout has been found.Usually departments are positioned one by one, Beginning with the department with the Highest A or E ratings.


Layout Planning Steps• Arrange work centers in order of dominant flow (objective

is to ensure resource/product flow at optimum cost/time)

A l d t/ fl ( Fl di / F T

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• Analyze product/resource flow ( Flow diagram/ From-To diagram)

• Include non-flow factors & combine with flow factors

• Determine space requirements

• Fit space arrangement into available space


Analyze product/ resource flow

Flow diagramFrom-to chart

Identify non-flow factors,Where significant

Activity-Relationship diagram

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Assess data and arrange work area

Activity arrangement diagram

Determine space arrangement plan

Space relationship diagram

Fit space arrangement in to available space

Floor planDetailed layout plan