ch07 Operations mgt

8/9/2019 ch07 Operations mgt

1/53

Copyright 2009 John Wiley & Sons, Inc.Copyright 2009 John Wiley & Sons, Inc.Beni AsllaniBeni Asllani

University of Tennessee at ChattanoogaUniversity of Tennessee at Chattanooga

Capacity and FacilitiesCapacity and FacilitiesOperations Management - 6thEdition

Operations Management - 6thEdition

Chapter 7Chapter 7

Roberta Russell & Bernard W. Taylor, IIIRoberta Russell & Bernard W. Taylor, III


2/53

Copyright 2009 John Wiley & Sons, Inc. 7-2

Lecture OutlineLecture Outline

Capacity Planning

Basic Layouts

Designing Process Layouts

Designing Service LayoutsDesigning Product Layouts

Hybrid Layouts


3/53


Capacity

Maximum capability to produceMaximum capability to produce

Capacity planningCapacity planning establishes overall level of productiveestablishes overall level of productive

resources for a firmresources for a firm

3 basic strategies for timing of capacity3 basic strategies for timing of capacityexpansion in relation to steady growth inexpansion in relation to steady growth in

demand (lead, lag, and average)demand (lead, lag, and average)


4/53


Capacity Expansion Strategies


5/53


Capacity (cont.)

Capacity increase depends on volume and certainty of anticipated demand

strategic objectives costs of expansion and operation

Best operating level % of capacity utilization that minimizes unit costs

Capacity cushion % of capacity held in reserve for unexpectedoccurrences


6/53


cono!ies o" Scalecono!ies o" Scale

it costs less per unit to produce high levels ofoutput fixed costs can be spread over a larger number ofunits

production or operating costs do not increaselinearly with output levels

quantity discounts are available for materialpurchases

operating efficiency increases as workers gainexperience


7/53Copyright 2009 John Wiley & Sons, Inc. 7-7

Best Operating Level for a Hotel


8/53Copyright 2009 John Wiley & Sons, Inc. 7-

#achine O$%ecties o"#achine O$%ecties o"'acility Layout'acility Layout

Minimize material-handling

costs Utilize space efficiently Utilize labor efficiently Eliminate bottlenecks Facilitate communication andinteraction

Reduce manufacturing cycletime

Reduce customer service time Eliminate wasted or redundantmovement

Increase capacity

Facilitate entry, exit, and placement

of material, products, and people Incorporate safety and securitymeasures

Promote product and servicequality

Encourage proper maintenanceactivities

Provide a visual control of activities Provide flexibility to adapt tochanging conditions

Arrangement of areas within a facility to:


9/53Copyright 2009 John Wiley & Sons, Inc. 7-9

SIC L*O+S

Process layouts group similar activities together according

to process or function they perform Product layouts

arrange activities in line according tosequence of operations for a particularproduct or service

Fixed-position layouts are used for projects in which productcannot be moved


10/53Copyright 2009 John Wiley & Sons, Inc. 7-!0

-rocess Layout in Serices-rocess Layout in Serices

Womenslingerie

Womensdresses

Womenssportswear

Shoes

Cosmeticsand jewelry

Entry anddisplay area

Housewares

Childrensdepartment

Mensdepartment


11/53Copyright 2009 John Wiley & Sons, Inc. 7-!!

#anu"acturing -rocess Layout#anu"acturing -rocess Layout



-rouct Layout -rouct Layout

InIn

OutOut



Description

Type of process

Product

Demand Volume Equipment

Description

Type of process

Product

Demand Volume Equipment

Sequential

arrangement ofactivities

Continuous, mass

production, mainlyassembly

Standardized, madeto stock

Stable High Special purpose

Process

Co!parison o" -rouctCo!parison o" -rouct

an -rocess Layoutsan -rocess Layouts

Functional

grouping ofactivities

Intermittent, job

shop, batchproduction, mainly

fabrication Varied, made toorder

Fluctuating Low General purpose

Product



Workers Inventory

Storage space Material handling Aisles SchedulingLayout decision

Goal

Advantage

Workers Inventory

Storage space Material handling Aisles Scheduling

Layout decision Goal

Advantage

Limited skills Low in-process, high

finished goods Small Fixed path (conveyor) Narrow Part of balancing

Line balancing Equalize work at each

station Efficiency

Process

Co!parison o" -rouctCo!parison o" -rouct

an -rocess Layoutsan -rocess Layouts Varied skills High in-process, low

finished goods Large Variable path (forklift) Wide Dynamic

Machine location Minimize material

handling cost Flexibility

Product



'i/e-osition Layouts'i/e-osition Layouts

Typical of projects inTypical of projects inwhich product producedwhich product producedis too fragile, bulky, oris too fragile, bulky, or

heavy to moveheavy to move Equipment, workers,Equipment, workers,materials, othermaterials, otherresources brought to theresources brought to the

sitesite Low equipment utilizationLow equipment utilization

Highly skilled laborHighly skilled labor

Typically low fixed costTypically low fixed cost

Often high variable costsOften high variable costs



1esigning -rocess Layouts1esigning -rocess Layouts

Goal: minimize material handling costsGoal: minimize material handling costs

Block DiagrammingBlock Diagramming minimize nonadjacent loadsminimize nonadjacent loads use when quantitative data is availableuse when quantitative data is available

Relationship DiagrammingRelationship Diagramming

based on location preference between areasbased on location preference between areas use when quantitative data is not availableuse when quantitative data is not available



loc 1iagra!!ingloc 1iagra!!ing

Unit loadUnit load quantity in whichquantity in which

material is normallymaterial is normallymovedmoved

Nonadjacent loadNonadjacent load

distance fartherdistance farther

than the next blockthan the next block

STEPSSTEPS create load summary chartcreate load summary chart

calculate composite (twocalculate composite (two

way) movementsway) movements develop trial layoutsdevelop trial layouts

minimizing number ofminimizing number of

nonadjacent loadsnonadjacent loads


18/53

Copyright 2009 John Wiley & Sons, Inc. 7-!

loc 1iagra!!ing3 /a!pleloc 1iagra!!ing3 /a!ple

DepartmentDepartment 11 22 33 44 55

Load Summary ChartLoad Summary Chart

FOM!"OFOM!"O #E$%"ME&"#E$%"ME&"

'' (( '))')) *)*)

++ (( +))+)) *)*)

,, -)-) (( .).) *)*)

.. '))')) (( -)-)** *)*) ((

' + ,

. *


19/53

Copyright 2009 John Wiley & Sons, Inc. 7-!9

loc 1iagra!!ing3loc 1iagra!!ing3

/a!ple (cont.)/a!ple (cont.)2 3 200 loads2 4 150 loads

1 3 110 loads1 2 100 loads4 5 60 loads3 5 50 loads2 5 50 loads3 4 40 loads1 4 0 loads1 5 0 loads

' + ,

. *

')) +))

'*)*)

*)

-)

.)

'')

/rid '

Nonadjacent Loads:110+40=150

' +

,

.

*

'))

+))

'*)

*)

*) -).)

'')

/rid +

Nonadjacent Loads:0


20/53


loc 1iagra!!ing3loc 1iagra!!ing3

/a!ple (cont.)/a!ple (cont.)

'

+

,

.

*,

+

*

' .

0a1 Initial 2loc3 diagram0a1 Initial 2loc3 diagram 021 Final 2loc3 diagram021 Final 2loc3 diagram

Block Diagram type of schematic layout diagram; includes space requirements


21/53

Copyright 2009 John Wiley & Sons, Inc. 7-2!

4elationship 1iagra!!ing4elationship 1iagra!!ing

Schematic diagram thatSchematic diagram that

uses weighted lines touses weighted lines todenote location preferencedenote location preference Muthers gridMuthers grid

format for displayingmanager preferences for

department locations


22/53


4elationship 1iagra!!ing3 /cel4elationship 1iagra!!ing3 /cel


23/53


4elationship4elationship

1iagra!!ing3 /a!ple1iagra!!ing3 /a!ple$roduction$roduction

O44icesO44ices

Stoc3roomStoc3room

Shipping andShipping andrecei5ingrecei5ing

Loc3er roomLoc3er room

"oolroom"oolroom

%% %%

%%

OO

OO

OOOO

OO

66

6666

66

EE77

II

A Absolutely necessaryE Especially importantI Important

O OkayU UnimportantX Undesirable


24/53


4elationship 1iagra!s3 /a!ple (cont.)4elationship 1iagra!s3 /a!ple (cont.)

0a1 elationship diagram o4 original layout0a1 elationship diagram o4 original layout

8ey98ey9 %%EE

II

OO

66

77

O44icesO44ices

Stoc3roomStoc3room

Loc3erLoc3erroomroom

"oolroom"oolroom

ShippingShippingandand

recei5ingrecei5ing

$roduction$roduction


25/53


021 elationship diagram o4 re5ised layout021 elationship diagram o4 re5ised layout

O44icesO44ices

Stoc3roomStoc3room

Loc3erLoc3erroomroom

"oolroom"oolroom

ShippingShippingandand

recei5ingrecei5ing

$roduction$roduction 8ey98ey9 %%EE

II

OO

66

77

4elationship 1iagra!s3 /a!ple (cont.)4elationship 1iagra!s3 /a!ple (cont.)


26/53


Co!puteri5e layoutCo!puteri5e layout

SolutionsSolutions CRAFT

Computerized Relative Allocation of FacilitiesTechnique

CORELAP Computerized Relationship Layout Planning

PROMODEL and EXTEND visual feedback allow user to quickly test a variety of scenarios

Three-D modeling and CAD integrated layout analysis available in VisFactory and similar software


27/53


1esigning Serice

Layouts Must be both attractive and functional Types

Free flow layoutsencourage browsing, increase impulse purchasing, are flexibleand visually appealing

Grid layoutsencourage customer familiarity, are low cost, easy to clean andsecure, and good for repeat customers

Loop and Spine layoutsboth increase customer sightlines and exposure to products,while encouraging customer to circulate through the entirestore


28/53


ypes o" Store Layoutsypes o" Store Layouts


29/53


1esigning -rouct

Layouts Objective

Balance the assembly line

Line balancing tries to equalize the amount of work at eachworkstation

Precedence requirements physical restrictions on the order in which operations

are performed Cycle time

maximum amount of time a product is allowed tospend at each workstation


30/53


Cycle i!e /a!pleCycle i!e /a!ple

Cd=

production time a5aila2le

desired units o4 output

Cd=0: hours ; -) minutes ! hour1

0'+) units1

Cd< < . minutes.:)

'+)


31/53


'lo6 i!e s Cycle i!e'lo6 i!e s Cycle i!e

Cycle time = max time spent at any stationCycle time = max time spent at any station

Flow time = time to complete all stationsFlow time = time to complete all stations

' + ,

. minutes. minutes . minutes. minutes . minutes. minutes

Flow time < . = . = . < '+ minutesFlow time < . = . = . < '+ minutes

Cycle time < ma; 0.> .> .1 < . minutesCycle time < ma; 0.> .> .1 < . minutes


32/53


""iciency o" Line an alance 1elay

ii

ii< '< ' ttii

nCnCaaEE


33/53


Line alancing -roceureLine alancing -roceure

1.Draw and label a precedence diagram

2.Calculate desired cycle time required for line

3.Calculate theoretical minimum number of workstations4.Group elements into workstations, recognizing cycletime and precedence constraints

5.Calculate efficiency of line

6.Determine if theoretical minimum number ofworkstations or an acceptable efficiency level hasbeen reached. If not, go back to step 4.


34/53


Line alancing3 /a!pleLine alancing3 /a!pleWO8 ELEME&"WO8 ELEME&" $ECE#E&CE$ECE#E&CE "IME 0MI&1"IME 0MI&1

%% $ress out sheet o4 4ruit$ress out sheet o4 4ruit (( )?')?'

@@ Cut into stripsCut into strips %% )?+)?+

CC Outline 4un shapesOutline 4un shapes %% )?.)?.

## oll up and pac3ageoll up and pac3age @> C@> C )?,)?,

)?')?'

)?+)?+

)?.)?.

)?,)?,#

@

C

%


35/53


Line alancing3 /a!ple (cont.)Line alancing3 /a!ple (cont.)

WO8 ELEME&"WO8 ELEME&" $ECE#E&CE$ECE#E&CE "IME 0MI&1"IME 0MI&1

%% $ress out sheet o4 4ruit$ress out sheet o4 4ruit (( )?')?'

@@ Cut into stripsCut into strips %% )?+)?+

CC Outline 4un shapesOutline 4un shapes %% )?.)?.

## oll up and pac3ageoll up and pac3age @> C@> C )?,)?,

Cd

< < < )?. minute.) hours ; -) minutes ! hour

->))) units

+.))

-)))

N< < < +?* , wor3stations'?)

)?.

)?' = )?+ = )?, = )?.

)?.


36/53



CCdd< )?.< )?.

NN< +?*< +?*

EM%I&I&/ EM%I&I&/WO8S"%"IO& ELEME&" "IME ELEME&"S

' % )?, @> C

@ )?' C> #

+ C )?) #, # )?' none

)?')?'

)?+)?+

)?.)?.

)?,)?,#

@

C

%


37/53


%> @ C #

Wor3

station '

Wor3

station +

Wor3

station ,

)?,

minute

)?.

minute

)?,

minute

CCdd< )?.< )?.

NN< +?*< +?*

E< < < )?:,, < :,?,A)?' = )?+ = )?, = )?.

,0)?.1

'?)

'?+



38/53


Co!puteri5e LineCo!puteri5e Line

alancingalancing Use heuristics to assign tasks toUse heuristics to assign tasks to

workstationsworkstations Longest operation timeLongest operation time

Shortest operation timeShortest operation time

Most number of following tasksMost number of following tasks

Least number of following tasksLeast number of following tasks

Ranked positional weightRanked positional weight


39/53


7y$ri Layouts7y$ri Layouts

Cellular layouts group dissimilar machines into work centers (called cells)that process families of parts with similar shapes orprocessing requirements

Production flow analysis (PFA) reorders part routing matrices to identify families of partswith similar processing requirements

Flexible manufacturing system automated machining and material handling systemsautomated machining and material handling systemswhich can produce an enormous variety of items

Mixed-model assembly line processes more than one product model in one line


40/53


Cellular Layouts

1.1.Identify families of parts with similarIdentify families of parts with similar

flow pathsflow paths

2.2.Group machines into cells based onGroup machines into cells based on

part familiespart families

3.3.Arrange cells so material movementArrange cells so material movement

is minimizedis minimized4.4.Locate large shared machines atLocate large shared machines at

point of usepoint of use


41/53


-arts 'a!ilies-arts 'a!ilies

% 4amily o4% 4amily o4

similar partssimilar parts% 4amily o4 related% 4amily o4 related

grocery itemsgrocery items


42/53


Original -rocess LayoutOriginal -rocess Layout

C% @ aw materials

%ssem2ly

'

+

,

.

*

- B

:

')

''

'+


43/53


-art 4outing #atri/-art 4outing #atri/

Machines

$arts ' + , . * - B : ') '' '+

% ; ; ; ; ;

@ ; ; ; ;C ; ; ;

# ; ; ; ; ;

E ; ; ;

F ; ; ;/ ; ; ; ;

H ; ; ;

Figure *?:Figure *?:


44/53


4eise Cellular Layout4eise Cellular Layout

,

-

%ssem2ly

'+

.

: ')

*

B

''

'+

% @ C

aw materials

Cell ' Cell + Cell ,


45/53


4eorere 4outing #atri/4eorere 4outing #atri/

Machines

$arts ' + . : ') , - * B '' '+

% ; ; ; ; ;

# ; ; ; ; ;F ; ; ;

C ; ; ;

/ ; ; ; ;

@ ; ; ; ;H ; ; ;

E ; ; ;


46/53



47/53


antages an 1isaantagesantages an 1isaantages

o" Cellular Layoutso" Cellular LayoutsAdvantagesAdvantages

Reduced materialReduced material

handling and transit timehandling and transit time Reduced setup timeReduced setup time

Reduced work-in-Reduced work-in-

process inventoryprocess inventory

Better use of humanBetter use of human

resourcesresources Easier to controlEasier to control

Easier to automateEasier to automate

DisadvantagesDisadvantages Inadequate part familiesInadequate part families

Poorly balanced cellsPoorly balanced cells Expanded training andExpanded training and

scheduling of workersscheduling of workers

Increased capitalIncreased capital

investmentinvestment


48/53


uto!ate #anu"acturing Celluto!ate #anu"acturing Cell

Source: J. . lac, 8Cellular

#anu"acturing Syste!s 4euce Setup

i!e, #ae S!all Lot

-rouction cono!ical.Industrial

Engineering (:oe!$er ;9


49/53


'le/i$le #anu"acturing'le/i$le #anu"acturing

Syste!s ('#S)Syste!s ('#S) FMS consists of numerous programmablemachine tools connected by an automatedmaterial handling system and controlled by

a common computer network FMS combines flexibility with efficiency

FMS layouts differ based on variety of parts that the system can process

size of parts processed average processing time required for partcompletion


50/53


'ulllo6n '#S


51/53


#i/e #oel#i/e #oel

sse!$ly Linessse!$ly Lines

Produce multiple models in any orderProduce multiple models in any order

on one assembly lineon one assembly line Issues in mixed model linesIssues in mixed model lines

Line balancingLine balancing

U-shaped linesU-shaped lines Flexible workforceFlexible workforce

Model sequencingModel sequencing


52/53


alancing +Shape Linesalancing +Shape Lines

% @ C

# E

$recedence diagram9$recedence diagram9

Cycle time < '+ minCycle time < '+ min

%>@ C># E

0a1 @alanced 4or a straight line0a1 @alanced 4or a straight line

min min '+ min'+ min , min, min

E44iciency < < < ?---- < --?B AE44iciency < < < ?---- < --?B A+.+.,-,-

+.+.,0'+1,0'+1

'+ min'+ min '+ min'+ min

C>#

%>@

E

021 @alanced 4or a 6Dshaped line021 @alanced 4or a 6Dshaped line

E44iciency < < < ')) AE44iciency < < < ')) A+.+.

+.+.

+.+.

+0'+1+0'+1


53/53

Copyright 2009 John Wiley & Sons, Inc.Copyright 2009 John Wiley & Sons, Inc.

All rights reserved. Reproduction or translationAll rights reserved. Reproduction or translation

o this !or" #eyond that per$itted in section %%o this !or" #eyond that per$itted in section %%o the %9' (nited States Copyright Act !ithouto the %9' (nited States Copyright Act !ithout

e)press per$ission o the copyright o!ner ise)press per$ission o the copyright o!ner is

unla!ul. Re*uest or urther inor$ation shouldunla!ul. Re*uest or urther inor$ation should

#e addressed to the +er$ission epart$ent,#e addressed to the +er$ission epart$ent,

John Wiley & Sons, Inc. -he purchaser $ay $a"eJohn Wiley & Sons, Inc. -he purchaser $ay $a"e

#ac"up copies or his/her o!n use only and not#ac"up copies or his/her o!n use only and not

or distri#ution or resale. -he +u#lisher assu$esor distri#ution or resale. -he +u#lisher assu$es

no responsi#ility or errors, o$issions, orno responsi#ility or errors, o$issions, or

ch07 Operations mgt

Documents

Transcript of ch07 Operations mgt