OM 3 Layout and Flow

Slack, Chambers and Johnston, Operations Management, 6th Edition, Nigel Slack, Stuart Chambers, and Robert Johnston 20107.1

7.1

Chapter 7

Layout and flow

Pearson Education Ltd. Rob Judges


7.2

Supply network design

Layout and Flow

Process technology

People, jobs and

organization

Product/service design

Design

Planning and control

Operations strategy

Improvement

Layout and flow

Layout and flow


7.3

Service process types

Mass services

Service shops

Manufacturing process types

Continuous processes

Mass processes

Batch processes

Basic layout types

Fixed-position layout

Functional layout

Cell layout

Product layout

The relationship between process and layout types

Jobbing processesProfessional services

Project processes


7.4

Fixed Position Layout Aviva Stadium


7.5 Advantages and disadvantages of fixed position layout

Fixed-position layout

Disadvantages

Advantages

Very high product and mix flexibility

Product/customer not moved

High variety of tasks for staff

Very high unit costs

Scheduling space and activities can be difficult


7.6 Functional layout in a library the path of one customer

Entrance Exit

To journal stack

Study desks

On-line and CD-ROM access room

Loan books in subject orderE

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Store room

Counter staffCopying area

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Current journals

Reserve collection

Reference section


7.7

Functional layout

Disadvantages

Advantages

High product and mix flexibility

Relatively robust in the case of disruptions

Easy to supervise

Low utilization

Can have very high WIP

Complex flow

Advantages and disadvantages of functional layout


7.8 Product/Customer Layout - Bottling


7.9

Product layout

Disadvantages

Advantages

Low unit costs for high volume

Opportunities for specialization of equipment

Can have low mix flexibility

Not very robust in the case of disruptionsWork can be very repetitive

Advantages and disadvantages of product layout


7.10 Cell Layout - UCD


7.11

Cell layout

Disadvantages

Advantages

Can give good compromise

Fast throughput

Group work can result in good motivation

Can be costly to rearrange existing layout

Can need more plant

Advantages and disadvantages of cell layout


7.12 A restaurant complex with all four basic layout types

Fixed-position layout service restaurant

Cell layout buffet

Line layout

cafeteria

Cool roomFreezer Vegetable prep Grill

Preparation

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Functional layout kitchen

Main course buffet

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Service line


7.13 Detailed design techniques

Fixed position Project management, resource location analysis, experience

Functional layout Complex permutations, efficiency, flow charts and relationship charts

Cell layout Cluster analysis or group technology, product flow analysis

Product layout assembly line balancing techniques, cycle times.


7.14

1 every 15 minutes

15 15 15 15

1 every 15 minutes

30 30

3030

Long and thin versus short and fat layouts

1 every 15 minutes

60

60

60

60

A 60 minute task with a required cycle time of 15 minutes


7.15 Long and thin versus short and fat

Advantages of long-thin processescontrolled flowsimple materials handlinglower capital requirement(no duplication)greater efficiencyhigher space utilization

Advantages of short-fat processeshigher mix flexibilityhigher volume flexibility greater robustnessless monotonous

higher ownership

Long and short describes the number of stages

Fat and thin describes the amount of work at each stage


7.16

Stages in Time Study

BasicTime

ObservedTime

RatingStandard Rating= X

BasicTime

Standard Time =

Allowances+

Standard time for element

Basic time for element

Observed time for element

Rating to adjust for

effortStandard

time for job

Allowances for relaxation

etc.


7.17

Learning Curve

Time to perform task reduces the more times the task is done.

With manual tasks, humans display learning at an exponential rate

Learning effect more evident for complex, manual and repetitive tasks.

Learning rate is a measure of the progressive reduction in time taken to complete successive tasks

T2 / T1 = T4 / T2 = T8 / T4 = learning rate


7.18

Example

Learning Rate = 75%, y1 = 1000hrs

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7.19

Actual Hrs vs Standard Hrs

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Set

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CP4 01Unit 32 @16,869 Hrs

Last set closed :


7.20

Learning Data

75% hand assembly/25% machining = 80% learning

50% hand assembly/50% machining = 85% 25% hand assembly/75% machining = 90%

Aerospace 85% Shipbuilding 80-85% Complex machine tools for new models 75-85% Repetitive machining or punch-press operations

90-95% Repetitive welding operations 90%

Documents

OM 3 Layout and Flow