11

Plant Location Plant Location And LayoutAnd Layout

Session2. ii & iii

22

33

Plant Location And LayoutPlant Location And Layout

The efficient operation of a plant depends up on the proper selection of the site and lay out of the plant.

The following factor have a significant influence on the choice of location site and lay out.

Differentiation of factors between the problems of location of site :

Choose the general area1. Conduct detailed survey to find out possible site.

2. Final decision be taken on detailed factors.

Source: Study material on Industrial Engineering-II, By Andhra Pradesh Productivity Council, Chp. No.3, From Pg No. 1 to 27

44

1. Integration with group companies

2. Availability of labor

3. Availability of housing

4. Availability of amenities

5. Availability of transport

6. Availability of materials

7. Availability of parking space

8. Availability of dirculation

9. Availability of services, gas-electricity, water, drainage and waste disposal

Factors which influence the Factors which influence the choice of Locationchoice of Location

55

10. Stability of land & climate

11. Local building and planning regulation

12. Room for expansion

13. Safety requirements

14. Cost of sight

15. Political situation

16. Industrial climate (Labor)

17. Subsidies from Government

Factors which influence the Factors which influence the choice of Locationchoice of Location

66

1. Identify the key factors.

2. Rank the chosen sites with appropriate weightage.

3. Examine all factors and rank them based on

importance – Rank factor by factor and not location

by location.

4. Multiply the ranking by the weightage factor. The

total indicates the desirability of the possible

location.

Selection of A Particular LocationSelection of A Particular Location

77

Selection of A Particular Location – Selection of A Particular Location – A Hypothetical ExampleA Hypothetical Example

Factor Weight

A B C D EIntegration 0 - 0 - 0 - 0 - 0 - 0Labor 9 1

9

5

45

4

36

2

18

3

27Housing 6 3

18

3

18

2

12

5

30

1

6Amenities 6 1

6

2

12

4

24

5

30

3

18Transport 4 5

20

4

16

3

12

2

8

1

4Materials 4 4

16

1

4

2

8

3

12

5

20Car park 6 3

18

4

12

5

30

1

6

2

12Circulation 6 1

6

4

24

3

18

5

30

2

12

Possible Location

88

Selection of A Particular Location – Selection of A Particular Location – Assessment of Possible Factory LocationAssessment of Possible Factory Location(1) (2) (3) (4) (5) (6) (7)

Services 5 1

5

2

1 0

2

10

5

25

4

20Land and Climate

2 4

8

2

4

5

10

3

6

1

2Planning Regulations

8 5

40

2

16

4

32

3

24

1

8Expansion 2 3

6

4

8

2

4

5

10

1

2Safety 0 -

0

-

0

-

0

-

0

-

0Cost 1 5

5

1

1

2

2

3

3

4

4Political Situation

0 -

0

-

0

-

0

-

0

-

0Special Subsidies

2 2

4

1

2

5

10

4

8

3

6Totals 161 184 208 210 141

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• Factors affecting the design of the plant.• Detailed design can be prepared by an architect with

a brief sent by the client which should indicate.

1. Accommodation required

2. Latest possible completion data

3. Quality / standards and expected life of the new building

4. Proposed site

5. Anticipated cost of plant.

Plant LayoutPlant Layout

1010

1. Size2. Head room required (height)3. Loads to be carried4. Access5. Lighting6. Ventilation and heating7. Services to be provided8. Waste disposal

Decision Considerations 1/2Decision Considerations 1/2

1111

9. Special process requirementsi. Temperature controlsii. Type of flooring vibrationsiii. Special security measuresiv. Special lighting needsv. Special amenities if any

10. Number of Floors

Decision Considerations 2/2Decision Considerations 2/2

1212

• Layout is the physical disposition of the plant and the various sections of the plant

• The layout will encompass both the location of the equipment within a specific department and location of different departments.

• Types of Layout– Product Layout– Process Layout

• The techniques of Layout are generally as discussed in work-study. However the process & Layout must be a creative one.

Plant LayoutPlant Layout

1313

1. Maximum flexibility

2. Maximum coordination

3. Maximum usage of volume (cubic space)

4. Maximum visibility

5. Maximum accessibility

6. Minimum distance of movement

7. Minimum handling

Criteria to be satisfied in a good layoutCriteria to be satisfied in a good layout

8. Minimum discomfort

9. Inherent safety

10. Maximum security

11. Uni flow

12. Visible routes

13. identification

1414

1. Reduced cost and process time through minimized material

handling.

2. Labor productivity through visible and open layout.

3. Easy accommodation of changes.

4. Maximum and better utilization of space.

5. Better quality and safer methods.

6. A conducive environment to motivate employees.

Advantages of a Good LayoutAdvantages of a Good Layout

1515

1. Collect all information needed

i. Type / quality/ quantity of work force

ii. Dimensional plan of space to be laid out

iii. Volume of work to be produced or material to be stored

iv. Operations, process, sequence and standard times

v. Equipment needed to carry out the production / operation

vi. Movement of material between the work station (quantity & method) and the frequency (to construct travel charts)

vii. Time for ageing, stabilizing, normalizing, e.t.c

Preparation of Layout 1/2Preparation of Layout 1/2

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viii.Quantity of material stores / sub stores in process storage etc & buffer stock

ix. Location of main stores and volumes to be stored

x. Lines of communication & fire exits

xi. Special security arrangements, burglars alarms, safety alarms etc.

xii. Inspection needs

xiii.Special needs for geographical location of specific section such as dispatch

xiv.Contingency arrangements for stand bye equipments.

Preparation of Layout 2/2Preparation of Layout 2/2

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1. String diagram

2. Flow Process chart

3. Travel Chart

4. Flow diagram

5. Multiple activity chart

6. Template Models

Tools used for preparing Plant LayoutsTools used for preparing Plant Layouts

1818

String diagram 1/6String diagram 1/6The string diagram is a scale plan or model on The string diagram is a scale plan or model on which a thread is used to trace and measure the which a thread is used to trace and measure the

distance traversed which has to be minimum by distance traversed which has to be minimum by •Workers•Material or•Equipment

during a specified sequence of eventsduring a specified sequence of events

1919

• Observe the clusters of points, pins, turning points.

• Also observe the grid lines which represent a measure of the distance between the points.

2020

Construction of a String diagramConstruction of a String diagram

• Step-1– Preparing a study chart

• Step-2 – Drawing a scale plan of the working area

• Step-3– Combining steps 1,2 to construct the final diagram

2121

Step-1Step-1:: Preparing a study chartPreparing a study chart

• Worker being studied is followed and all the points along the working areas are noted in a study sheet until a representative picture of the workers is obtained.

• Thus the movements are noted down for enough number of cycles so as to capture the actual work in terms of the journey made by the worker with their respective frequencies.

2222

Step-2Step-2:: Drawing a scale plan of the Drawing a scale plan of the working areaworking area

• Machines, benches, stores and all other points at which calls are made are drawn to scale together with doorways, pillars etc that effect the path movements.

• Then attachments like soft wood, composition board and pins are driven firmly at every point. Pins are driven also at turning points on the route.

• This ensure a shop floor environment which helps to do the study accurately.

2323

Step-3Step-3:: combining the steps 1 and 2combining the steps 1 and 2

• A measured length of thread is wound from the starting point of the movement of the worker and leading through all the points on the path of the worker in the same order noted in the step-1

• This results in a String diagram.

2424

Process activity symbolsProcess activity symbols

• Operation

• Inspection

• Transport

• Temporary storage or Delay

• Permanent storage

2525

Flow process chart 2/6Flow process chart 2/6

PurposePurpose::

To set out the sequence of the flow of a To set out the sequence of the flow of a product or a procedure by recording all the product or a procedure by recording all the events under review ( Inspection ) using the events under review ( Inspection ) using the appropriate process chart symbols.appropriate process chart symbols.

2626

Process chart symbolsProcess chart symbols

• Used to represent different types of activities or events.

• Very convenient, widely understood type of short hand, saves a lot of writing and helps in making the sequence of activities clear.

2727

Three typesThree types of of flow process chartsflow process charts

• Man type– Flow chart which records what the worker does

• Material type– Flow chart which records how material is handled or

treated

• Equipment type– Flow chart which records how the equipment is

used

2828

Man typeMan type flow process chart for dinner at a hospital flow process chart for dinner at a hospital

2929

Travel chart Travel chart 3/63/6

• A travel chart is a tabular record for presenting quantitative data about the movements of workers, materials or equipment between any number of places over any given period of time.

3030

Why Travel chart ?Why Travel chart ?

Although the string diagram is a neat and effective way of record the movement of worker or material for critical examination,

o they take long time to construct o look increasingly like a complex maze with

increasing complexity of movement paths

When the movement patterns are complex, the travel chart is quicker and more manageable to record.

3131

Travel chartTravel chart

3232

More about Travel chartMore about Travel chart

• Always a square

• A column at (m,n) is checked only when there is a direct movement from station at m to station at n direct.

• The number of times a column at (m,n) is checked over a period of time gives the frequency of movement of a worker or material.

• The matrix is always a symmetrical matrix.

3333

FLOW DIAGRAM FLOW DIAGRAM (4/6)(4/6)

3434

ACTIVITY DIAGRAMACTIVITY DIAGRAM

• Multiple activity chart is a chart on which the activities of more than one subject (workers, machine or item of equipment) are each recorded on a common time scale to show their inter relationship.

3535

ACTIVITY DIAGRAMACTIVITY DIAGRAM……

• No such time scales are used in the charts we saw previously.

• Can be used equally effectively even if there is no movement of workers. Primary focus, if movement of workers is there, is to identify the idle time on the part of either the workers or the machines.

3636

MULTIPLE ACTIVITY CHARTMULTIPLE ACTIVITY CHART

3737

TEMPLATE MODELSTEMPLATE MODELS

• Template models are used to study the layout and the positioning of various machines by pasting templates on the plant layout diagram.

• This can be extended by using the string diagram technique to visualize the flow of the material.

3838

3939

A String Diagram Storing Tiles (Original Method)

4040

A String Diagram Storing Tiles (Improved Method)

4141

Flow Diagram Serving Dinners in a Hospital Ward

4242

Flow Process Chart – Man Type Dinners in a Hospital Ward

4343

Having located the departments and the equipments to be stationed within the

department, the layout process is generally a trial and process keeping the principles of layout and material

handling in mind.

Layout of work stationsLayout of work stations

4444

1. Locate key operations

2. Locate main gangways

3. Avoid back tracking/crisis crossing

4. Locate doorways (in/exit)

5. Locate remaining work areas

6. Locate minor gangways / aisles

7. Locate the departments and sections with the plant & matching

8. Complete location of subsidiary equipments (materials, tool boxes, scrap bins, telephones, electric panels)

9. Check final layout against companies general policies and specifications.

Planning SequencePlanning Sequence

4545

References References

• “Introduction to Work Study”, chapter 10, pages 110-130, International Labour Office, Geneva – Publisher: Raju Primlani for Oxford & IBH

Publishing Co. Pvt. Ltd., New Delhi.

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