Basic Quality Control Tools

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    The Tools of Quality

    Dr. Rathanraj K J

    Professor, BMSCE

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    Improving the System

    “The objective of the system is tosatisfy the cstomer!.

    “" quality system ses thebsiness mo#e$ %ith a focs onthe cstomer an# inc$#es

    #ynamics of contina$im&rovement, chan'e, &$annin',an# rene%a$!.

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    Quality System Model

    Customer 

    Procedures

    Legal

    Req’ts

    R&D

    Technology

    People

    Plant &

    Equipment

       R  e  n

      e   w  a   l

       C   h  a  n

      g   e

    P   

    l   a  n  n  i   n   g  

    C  o  n  t  i   n  u  a  l    

    I   m   p  r  o  v  e  m  

    e  n  t  

     Adapted from S.

     Thomas Foster

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    Quality System Model

    The variab$es an# re$ationshi&s of the

    (a$ity system are an interconnecte#

    net%or) that interact to achieve an en#.

    Peo&$e are the most im&ortant as&ect

    of the system.

    *o% &eo&$e are mana'e# is im&ortant

    in re$easin' an or'ani+ations &otentia$.

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    Basic 7 (B7) Tools of Qualityig

    Picture

    Data

    !nalysis

    Data

    Collection

    Pro"lem

    Identi#icationPrioriti$ation

    %low

    Chart

    Chec

    'heet

    (isto)

    grams

    'catter 

    Plots

    Control

    Charts

    Cause

    E##ect

    Pareto

    !nalysis

     Adapted from S.

     Thomas Foster

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    Flowcharts

    - ra&hic re&resentation of system

    or &roce#re f$o%

    -Can be se# for both macro an#micro $eve$ &rocesses

    - Promotes system n#erstan#in'

    an# %i$$ i#entify 'a&s in &roce#ra$

    $o'ic

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    Flowcharting Steps

    -  "'ree on a stan#ar# set ofsymbo$s

    - C$ear$y commnicate &r&ose ofthe f$o%chart

    - /bserve the %or)0 sha#o% the%or)ers

    - Deve$o& f$o%chart of the &rocess- Revie% %ith the em&$oyees an#

    a#jst as necessary.

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    Flowcharts

    - 1$o%charts

     2 ra&hica$ #escri&tion of ho% %or) is

    #one.

     2 3se# to #escribe &rocesses that are to

    be im&rove#.

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    Flow iagrams

    4 Dra% a f$o%chart for %hatever yo

    #o. 3nti$ yo #o, yo #o not )no%

    %hat yo are #oin', yo jst have a

     job.!

     55 Dr. 6. E#%ar#s Demin'.

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    Flowchart

     "ctivity

    Decision7es7es

    8o8o

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     Flowchart

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    Flow iagrams

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    Flow iagrams

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    !hec" Sheets

    Chec) Sheets 2 tab$ar or schematic#ata 'atherin' too$s se# to formhisto'rams an# other 'ra&hs

    To set & a chec) sheet9:. ;#entify common #efects occrrin' in the

    &rocess.

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    - The format for recor#in' a$$ the

    necessary information to e>ecte

    &reventive &$ans an# to enab$e

    #eve$o&ment of strate'ies for

    im&rovement, common$y )no%n

    as Data Sheet, ?o' Boo),

    ;ns&ection Recor#, Sche#$e ofEn(iry has been terme# chec)

    sheet in this conte>t.

    !hec" Sheets

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    !hec" Sheet #$ample

    Pro"lem Type

    Set& rotines

    not stan#ar#i+e#

    Missin' e(i&ment

    for set&

    1ai$re to se&arate

    interna$ an# e>terna$

    tas)s

    E>tensive machineresettin' an# &a&er 

    chan'e

    /ther 

        M   o   n    #   a

       y

        T      e   s    #   a

       y

        6   e    #   n   e

       s    #   a   y

        T    h      r   s    #

       a   y

        1   r    i    #   a   y

        T   o    t   a    $

     Adapted from S.

     Thomas Foster

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    !%&T#&TS %F ' !#! S##T

    -   Identity  &artic$ars to enab$e traceability  $i)e or'ani+ation, #ate,

    &roject, cstomer, s&&$ier, s&ecifications, batch or $ot nmber, asa&&$icab$e.

    -  "ssociate# hman resorce an# E(i&ments if any

    - ;n&t@sA, im&$yin' consm&tion of resorces of a$$ )in#s %ith

    &ertinent #etai$s of their (antity an# a$$ie# &arameters $i)e &rity or

    stren'th or si+e as the case may be.- Process &arameters

    - Environmenta$ &arameters of concern if any

    - Metho# of sam&$in', sam&$e si+e, fre(ency of sam&$in'

    - ;ns&ection an# test faci$ities se# or avai$e#

    - ;ns&ection an# test metho#, $east cont or visa$ stan#ar#s a#a&te#- Corres&on#in' ot&t@sA %ith #etai$s of &arameters of interest

    - ;n#ices or a&&ro&riate fnctions of observations ma#e

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    'ttri*ute Inspection

     "n i$$strative chec) sheet for an attribte #ata

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    +aria*le Inspection

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    ,ac"ing ,rocess " ty&ica$ chec) sheet for $ist of items to be &ac)e# an# or #is&atche#

    to a cstomer sch as a stan#ar# $ist of s&ares accom&anyin' amachine too$ as accessories

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    -or" Sampling Study

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    ' specimen chec" sheet for recording

    Feed *ac" from !ustomers

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    ' specimen chec" sheet for setting

    approval

    k≤2

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    istograms

    *isto'rams 2 bar chart 'ra&hica$re&resentation of #ata, a$so se# toobserve the sha&e of #ata

    R$es for #eve$o&in' histo'rams9 6i#th of bars mst be consistent

    C$asses mst be mta$$y e>c$sive an#

    a$$5inc$sive R$e of thmb for the nmber of c$asses9

    nk ≤2

    2log/lognk  =

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    istograms (cont.)

     

    n  nmber of ra% #ata va$es

    k nmber of c$asses

    3sin' this form$a, %e fin#9

    2log/lognk  ≥

    Number of Observations Number of Classes

    9 to 16 4

    17 to 32 5

    33 to 64 6

    65 to 128 7

    129 to 256 8

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    istogram #$ample

    Reference9

    ?ab :, C;T =

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    istogram of weight of ta*lets in grams

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    istogram (It is called Bar !hart/ when applied to

    attri*ute data) showing fre0uency of non1

    conforming *o**ins in samples of si2e 34 each.

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    istogram of honing angle of shaving *lades.

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    !ause1and1#ffect iagrams

    Case5an#5Effect Dia'rams 2 se# tomove to $o%er $eve$s of abstraction inso$vin' &rob$ems

     ".K.".9 ;shi)a%a Case5an#5Effect or1ishbone or ;shi)a%a Dia'ram

    1ish s)e$eton sha&e, the &rob$em is thehea#, major cases are the ribs, sb5cases form sma$$er bones of the ribs

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    !ause1and1#ffect (cont.)

    1ishbone #ia'rams create# #rin'brainstormin' %ith these ste&s9

    :. State the &rob$em c$ear$y as the hea#.

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    Fish*one iagram #$ample

    Ref9 http://courses.bus.ualberta.ca/orga432reshe!/!ishbone.html 

    http://www.smartdraw.com/examples/pert/groupsculpture.htmhttp://www.smartdraw.com/examples/pert/groupsculpture.htm

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    !ause and #ffect diagram of nonconforming

    thic"ness of coating

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    !ause and #ffect diagram of slag

    inclusion in a cast iron product

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    !ause and effect diagram of a thermos flas" failing

    to pass the temperature retention test.

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    !ause and effect diagram for preparation of tasty

    tea

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    Improved version of the cause and effect diagram

    for preparation of tasty tea

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    !ause and effect diagram of performance

    of a team in a game of sport

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    !ause and effect diagram for national status on

    0uality in the world mar"et

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    ,areto ,rinciple

    - i$fre#o Pareto @:5:H

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    ,areto !harts

    Pareto Charts 2 se# to i#entify

    an# &rioriti+e &rob$ems to be

    so$ve#

    *isto'rams ai#e# by the

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    ,areto !harts (cont.)

    R$es for constrctin' Pareto

    charts9 ;nformation mst be se$ecte# base#

    on ty&es or c$assifications of #efectsthat occr as a res$t of a &rocess.

    Data mst be co$$ecte# an#

    c$assifie# into cate'ories. " histo'ram or fre(ency chart is

    constrcte# sho%in' the nmber of

    occrrences.

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    ,areto !harts (cont.)

    Ste&s se# in Pareto "na$ysis9

    :. atherin' cate'orica$ #ata re$atin'

    to (a$ity &rob$ems.

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    S%M# #5'M,6#S

    Tab$e Sho%in' 8atre, 1re(ency an# Ran) of 8on5conformity.

    /r'anisation9 /R Pro#ct9 PR/ Month9 M/7R

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    Tab$e Sho%in' Ran), Percent fre(ency an# &ercent cases.

    /r'anisation9 /R Pro#ct9 PR/ Month9 M/7R

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    ,areto iagram of nonconforming *atches of an

    adhesive

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    eavy #lectrical ,lant

    Tab$e Sho%in' case %ise &ercent contribtion to

    nonconformities amon' Trbine B$a#es

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    ,areto analysis of nonconformities among Tur*ine

    Blades

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    Scatter iagrams

    Scatter P$ots @Dia'ramsA 2 se# toe>amine re$ationshi&s bet%eenvariab$es

    Ste&s for settin' & a scatter &$ot9:. Determine  x  @in#e&en#entA an# y  

    @#e&en#entA variab$es

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    Scatter iagram #$ample

    ..H:.:.:*"served+alue5

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    Figure S owing relations ip *etween initial

    and final setting times of cement

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    !%MM%&6 %BS#8+# S!'TT#8

    I'98'MS

    %igure 'howing scatter diagrams indicating no

    worthwhile relationship/

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    Figure S owing scatter diagrams indicating

    wea" linear relations ips

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    Figure S owing scatter diagrams indicating

    strong linear and curvilinear relations ips

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    !ontrol !harts

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    !ontrol !harts

    Contro$ Charts 2 se# to #etermine if a

    &rocess %i$$ &ro#ce a &ro#ct or

    service %ith consistent measrab$e

    &ro&erties

    N an# R charts are se# to'ether, an#

    are ca$c$ate# from the same ra% #

    Contro$ Charts 2 se# to #etermine if a

    &rocess %i$$ &ro#ce a &ro#ct or

    service %ith consistent measrab$e

    &ro&erties

    N an# R charts are se# to'ether, an#

    are ca$c$ate# from the same ra% #ata

    5 d 8 !h t # l

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    5 and 8 !hart #$amples

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    Control Charts

    !ontrol chart functions

    - Contro$ charts are #ecision5ma)in'too$s 5 they &rovi#e an economic basisfor #eci#in' %hether to a$ter a &rocessor $eave it a$one

    - Contro$ charts are &rob$em5so$vin'too$s 5 they &rovi#e a basis on %hich toform$ate im&rovement actions

    - SPC e>&oses &rob$ems0 it #oes notso$ve themO

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    Control Charts

    !ontrol charts

    - Contro$ charts are &o%erf$ ai#s to

    n#erstan#in' the &erformance of

    a &rocess over time.

    PROCESSPROCESS

    Input Output

    What’s causing variability?

    ! t l h t id tif

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    Control Charts

    !ontrol charts identify

    variation- Chance cases 5 “common case!

     2 inherent to the &rocess or ran#om an# not

    contro$$ab$e

     2 if on$y common case &resent, the &rocess

    is consi#ere# stab$e or “in contro$!

    -  "ssi'nab$e cases 5 “s&ecia$ case!

     2 variation #e to otsi#e inf$ences

     2 if &resent, the &rocess is “ot of contro$!

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    Control Charts

    !ontrol charts help us learn more

    a*out processes

    - Se&arate common an# s&ecia$

    cases of variation

    - Determine %hether a &rocess is in a

    state of statistica$ contro$ or ot5of5contro$

    - Estimate the &rocess &arameters

    @mean, variationA an# assess the&erformance of a &rocess or its

    ca&abi$ity

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    Control Charts

    !ontrol charts to monitor

    processes

    - To monitor ot&t, %e se a contro$ chart

     2 %e chec) thin's $i)e the mean, ran'e,

    stan#ar# #eviation

    - To monitor a &rocess, %e ty&ica$$y se t%o

    contro$ charts

     2 mean @or some other centra$ ten#ency

    measreA

     2 variation @ty&ica$$y sin' ran'e or stan#ar#

    #eviationA

    !ontrol chart

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    Control Charts

    !ontrol chart

    components

    - Center$ine

     2 sho%s %here the &rocess avera'e is

    centere# or the centra$ ten#ency of

    the #ata- 3&&er contro$ $imit @3C?A an#

    ?o%er contro$ $imit @?C?A

     2  #escribes the &rocess s&rea#

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    Control Charts

    !ontrol chart for varia*les

    - ariab$es are the measrab$emeasrab$e

    characteristics of a &ro#ct or

    service.

    - Measrement #ata is ta)en an#

    arraye# on charts.

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    Control Charts

    51*ar and 8 charts

    - The N5bar chart 5 se# to #etect

    chan'es in the mean bet"een

    sb'ro&s

     2 tests centra$ ten#ency or $ocationeffects

    - The R chart 5 se# to #etect

    chan'es in variation %ithinsb'ro&s

     2 tests #is&ersion effects

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    Control Charts

    Step : efine the pro*lem

    - 3se other (a$ity too$s to he$&

    #etermine the 'enera$ &rob$em

    thats occrrin' an# the &rocess

    thats ss&ecte# of casin' it. 2 brainstorm sin' case an# effect

    #ia'ram, %hy5%hy, Pareto charts,

    etc.

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    Control Charts

    Step 3 Select a 0uality

    characteristic to *e measured

    - ;#entify a characteristic to st#y 5 for

    e>am&$e, &art $en'th or any other

    variab$e affectin' &erformance

     2 ty&ica$$y choose characteristics %hichare creatin' (a$ity &rob$ems

     2 &ossib$e characteristics inc$#e9 $en'th,

    hei'ht, viscosity, co$or, tem&eratre,ve$ocity, %ei'ht, vo$me, #ensity, etc.

    St ; !h * i

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    Control Charts

    Step ; !hoose a su*group si2e

    to *e sampled

    - Choose homo'eneos sb'ro&s

     2 *omo'eneos sb'ro&s are &ro#ce#

    n#er the same con#itions, by the same

    machine, the same o&erator, the same mo$#,

    at a&&ro>imate$y the same time.

    - Try to ma>imi+e chance to #etect

    #ifferences bet%een sb'ro&s, %hi$e

    minimi+in' chance for #ifference %ith a'ro&.

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    Control Charts

    %ther guidelines

    - The $ar'er the sb'ro& si+e, the moresensitive the chart becomes to sma$$

    variations.

    - This increases #ata co$$ection costs.

    - Destrctive testin' may ma)e $ar'e

    sb'ro& si+es infeasib$e.

    - Sb'ro& si+es sma$$er than arent

    re&resentative of the #istribtion avera'es.- Sb'ro&s over : sho$# se S chart.

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    Control Charts

    Step < !ollect the data

    - Rn the &rocess ntoche# to 'ather

    initia$ #ata for contro$ $imits.

    - enera$$y, co$$ect

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    Control Charts

    Step = etermine trial

    centerline

    - The center$ine sho$# be the &o&$ation mean, µ

    - Since it is n)no%n, %e se N #ob$e bar, or the

    'ran# avera'e of the sb'ro& avera'es.

    m

    m

    i

    i∑=

    =  1

    X

    X

    St > t i t i l t l li it

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    Control Charts

    Step > etermine trial control limits

    1 5*ar chart

    - The norma$ crve #is&$ays the

    #istribtion of the sam&$e avera'es.

    -  " contro$ chart is a time5#e&en#ent

    &ictoria$ re&resentation of a norma$crve.

    - Processes that are consi#ere# n#er

    contro$ %i$$ have HH.G=L of their

    'ra&he# avera'es fa$$ %ithin si>stan#ar# #eviations.

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    Control Charts

    ?!6 6!6 calculation

    deviationstandard

    3XLCL

    3XUCL

    =

    −=

    +=

    σ  

    σ  

    σ  

    t i i lt ti l f

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    Control Charts

    etermining an alternative value for

    the standard deviation

    m

    m

    i

    i∑==   1R 

    R AXUCL2

    +=

    R AXLCL2

    −=

    Step 7 etermine trial control

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    Control Charts

    Step 7 etermine trial control

    limits 1 8 chart

    - The ran'e chart sho%s the s&rea# or#is&ersion of the in#ivi#a$ sam&$es %ithin

    the sb'ro&.

     2   ;f the &ro#ct sho%s a %i#e s&rea#,then the in#ivi#a$s %ithin the

    sb'ro& are not simi$ar to each other.

     2 E(a$ avera'es can be #eceivin'.

    - Ca$c$ate# simi$ar to >5bar charts0

     2 3se D= an# DD

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    Control Charts

    81*ar chart e$ceptions

    - Becase ran'e va$es cannot be

    ne'ative, a va$e of is 'iven for

    the $o%er contro$ $imit of sam&$e

    si+es of si> or $ess.

    Step @ #$amine the process

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    Control Charts

    Step @ #$amine the process 1

    Interpret the charts

    -  " &rocess is consi#ere# to be stab$e an# in a

    state of contro$, or n#er contro$, %hen the

    &erformance of the &rocess fa$$s %ithin the

    statistica$$y ca$c$ate# contro$ $imits an#e>hibits on$y chance, or common cases.

    !onse0uences of

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    Control Charts

    !onse0uences of

    misinterpreting the process

    - B$amin' &eo&$e for &rob$ems that they cannotcontro$

    - S&en#in' time an# money $oo)in' for

    &rob$ems that #o not e>ist

    - S&en#in' time an# money on nnecessary

    &rocess a#jstments

    - Ta)in' action %here no action is %arrante#

    -  "s)in' for %or)er5re$ate# im&rovements%hen &rocess im&rovements are nee#e# first

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    Control Charts

    ,rocess variation

    - 6hen a system is sbject to on$ychance cases of variation, HH.G=L of

    the measrements %i$$ fa$$ %ithin =

    stan#ar# #eviations

     2 ;f : sb'ro&s are measre#, HHG %i$$

    fa$$ %ithin the si> si'ma $imits.

    !h t

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    Control Charts

    !hart 2ones

    - Base# on or )no%$e#'e of the norma$ crve, a

    contro$ chart e>hibits a state of contro$ %hen9

     2 T%o thir#s of a$$ &oints are near the center

    va$e.

     2 The &oints a&&ear to f$oat bac) an# forthacross the center$ine.

     2 The &oints are ba$ance# on both si#es of the

    center$ine.

     2 8o &oints beyon# the contro$ $imits. 2 8o &atterns or tren#s.

    Id tif i tt

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    Control Charts

    Identifying patterns

    -Tren#s 2 stea#y, &ro'ressive chan'es in $eve$

    - Chan'e, jm&, or shift in $eve$

    - Rns 5 G &oints above or be$o%0 si>

    increasin' or #ecreasin', c$sters

    - Recrrin' cyc$es

    - T%o &o&$ations

    - Mista)es

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    Control Charts

    Step A 8evise the charts

    - ;n certain cases, contro$ $imits arerevise# becase9

     2 ot5of5contro$ &oints %ere inc$#e# in

    the ca$c$ation of the contro$ $imits. 2 The &rocess is in5contro$ bt the

    %ithin sb'ro& variation si'nificant$y

    im&roves.

    8 i i th h t

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    Control Charts

    8evising the charts

    - ;nter&ret the ori'ina$ charts

    - ;so$ate the cases

    - Ta)e corrective action

    - Revise the chart 2 /n$y remove &oints for %hich yo

    can #etermine an assi'nab$e case

    Step :4 'chie e the p rpose

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    Control Charts

    Step :4 'chieve the purpose

    - /r 'oa$ is to #ecrease thevariation inherent in a &rocess over

    time.

    -  "s %e im&rove the &rocess, thes&rea# of the #ata %i$$ contine to

    #ecrease.

    - a$ity im&rovesOO

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    Process Capability

    ,rocess !apa*ility

    efining process

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    Process Capability

    efining process

    capa*ility

    - Process ca&abi$ity refers to theabi$ity of the &rocess to meet the

    s&ecifications set by the cstomer

    or #esi'ner.

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    Process Capability

    ,rocess capa*ility analysis

    - /bjective is to #etermine ho% %e$$ theot&t from a &rocess meetss&ecification $imits

    -Com&are tota$ &rocess variation an#to$erance.

    LSL USL

    -3σ +3σ arg!t

    Individual values compared

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    Process Capability

    Individual values compared

    with averages

    - 6hen #istribtions of avera'es arecom&are# to #istribtions of in#ivi#a$

    va$es, the avera'es are 'ro&e#

    c$oser to the center va$e than are the

    in#ivi#a$ va$es, as #escribe# by the

    centra$ $imit theorem.

    - 6hat #oes this im&$y for avera'es in

    contro$ $imits verss in#ivi#a$ va$es ins&ecification $imitsI

    #stimation of population sigma

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    Process Capability

    #stimation of population sigma

    from sample data

    - The re$ationshi& bet%een the stan#ar##eviation for in#ivi#a$ va$es an# the

    stan#ar# #eviation for their avera'es is 'iven

    by the form$a9

    n x

    σ  

    σ     = Wh!r! n " subgr#up sa$pl! si%!

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    Process Capability

    To simplify calculation

    - ;f the &rocess can be assme# to be norma$,the &o&$ation stan#ar# #eviation can beestimate# from either the stan#ar# #eviationassociate# %ith the sam&$e stan#ar#

    #eviation or the ran'e9

    d 2

    R =∧

    σ   #r

    c4

    S=∧

    σ  

    !ontrol limits and specification

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    Process Capability

    !ontrol limits and specification

    limits

    - Nbar charts #o not ref$ect ho% %i#e$ythe in#ivi#a$ va$es com&osin' the

    &$ottin' avera'es s&rea#.

    - The s&rea# can on$y be seen byobservin' %hat is ha&&enin' on the s

    or r chart.

    The Si$ sigma spread versus

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    Process Capability

    The Si$ sigma spread versus

    specification limits

    - Case ;9 Fσ  Q 3S? 5 ?S?- Most #esirab$e0 in#ivi#a$ va$es fa$$ %ithin

    s&ecification $imits

    - Case ;;9 Fσ  3S? 5 ?S?- /)ay, as $on' as the &rocess remains in contro$

    - Case ;;;9 Fσ  3S? 5 ?S?- 3n#esirab$e0 &rocess inca&ab$e of meetin'

    s&ecifications

    !alculating process capa*ility

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    Process Capability

    !alculating process capa*ility

    indices

    - Process ca&abi$ity in#ices9 ratiosthat (antify the abi$ity of a

    &rocess to &ro#ce %ithin

    s&ecifications

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    & 7 (&7) T l f I t

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    &ew 7 (&7) Tools for Improvement

    1ocses on 'ro& &rocesses an##ecision ma)in'

    Recommen#e# that the 8G too$s

    be se# in a “cyc$e of activity,!

    %herein on too$ &rovi#es in&ts to

    another too$ @&.

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    y y p

    0nnown 1nown

    LogicalCreative

    !##inity Diagram

    !ctivity -etwor

    Diagram

    Process Decision

    Program Chart

    2atri,

    Diagram

    Prioriti$ation

    2atrices

    Tree Diagram3

    'ystem %low

    Interrelationship

    Diagraph

    'ffinit iagrams

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    'ffinity iagrams

     "ffinity Dia'rams 2 creates a hierarchyof i#eas on a $ar'e srface

    3sef$ to srface a$$ isses re$ate# to a&rob$em

    *e$&s 'ro&s conver'e on a set

    nmber of themes or i#eas

    'ffinity iagram Steps

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    'ffinity iagram Steps

    :. ;#entify &rob$em. Create a c$ear,concise statement of the isse.

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    'ffinity iagram Steps (cont.)

    F.  "$$ &artici&ants si$ent$y an# (ic)$ymove car#s into &i$es %ith simi$arthemes.

    G. Do not #iscss #isa'reement on car#

    &$acement, sim&$y move it.. /nce consenss @a$$ car#s in 'ro&s

    an# car# movement has sto&&e#Acreate hea#er car#s.

    H. Dra% finishe# affinity #ia'ram an#&rovi#e a %or)in' co&y for a$$&artici&ants.

    'ffinity iagram #$ample

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    Ref9

    http://mot.vuse.van

    derbilt.edu/mt322/#

    !!inity.htm

    Ref9

    http://""".in!odesign.com.au/usab

    ilityresources/general/a!!initydi agramming.asp

    Interrelationship iagrams

    http://www.flowbiz.com.au/flowbiz/products/charter/http://www.flowbiz.com.au/flowbiz/products/charter/http://www.flowbiz.com.au/flowbiz/products/charter/http://www.vanderbilt.edu/Engineering/CIS/Sloan/web/es130/quality/newtool.htmhttp://www.vanderbilt.edu/Engineering/CIS/Sloan/web/es130/quality/newtool.htmhttp://www.vanderbilt.edu/Engineering/CIS/Sloan/web/es130/quality/newtool.htmhttp://www.vanderbilt.edu/Engineering/CIS/Sloan/web/es130/quality/newtool.htmhttp://www.vanderbilt.edu/Engineering/CIS/Sloan/web/es130/quality/newtool.htmhttp://www.vanderbilt.edu/Engineering/CIS/Sloan/web/es130/quality/newtool.htmhttp://www.flowbiz.com.au/flowbiz/products/charter/http://www.flowbiz.com.au/flowbiz/products/charter/http://www.flowbiz.com.au/flowbiz/products/charter/

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    Interrelationship iagrams

    ;nterre$ationshi& Dia'rams 2 sho%re$ationshi&s bet%een #ifferent

    isses

    *e$&f$ in i#entifyin' the most

    im&ortant isse

    Interrelationship iagram Steps

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    :. P$ace car#s %ith re$ate# isses from

    affinity #ia'ram in co$mns %ith 'a&sbet%een them.

    amine car#s in#ivi#a$$y $oo)in' forisses case# or inf$ence# by the

    isse. Dra% a one5%ay arro% fromthe “case! to the “one inf$ence# bythe case.! Re&eat nti$ a$$ isses#iscsse#.

    =. Revie%, ma)e revisions, then contthe of arro%s &ointin' to each notean# %rite the s on the notes.

    Interrelationship iagram Steps

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    Interrelationship iagram Steps

    . ;#entify car#s %ith the most arro%s as“)ey factors! @no more than to :A.Bo>es %ith severa$ arro%s a$tho'hnot )ey factors can be #ro&&e# at this

    &oint. Bo>es %ith ot'oin' arro%sten# to be root cases, those %ithincomin' arro%s ten# to be&erformance in#icators.

    . Dra% a #ob$e bo> aron# )eyfactors an# brainstorm %ays toa##ress these isses.

    Interrelationship iagram #$ample

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    Ref9

    http://""".sm

    artdra".com/t 

    utorials/bpm/ 

    bpm$%.htm

    Tree iagrams

    http://www.smartdraw.com/tutorials/bpm/bpm13.htmhttp://www.smartdraw.com/tutorials/bpm/bpm13.htmhttp://www.smartdraw.com/tutorials/bpm/bpm13.htmhttp://www.smartdraw.com/tutorials/bpm/bpm13.htmhttp://www.smartdraw.com/tutorials/bpm/bpm13.htmhttp://www.smartdraw.com/tutorials/bpm/bpm13.htmhttp://www.smartdraw.com/tutorials/bpm/bpm13.htmhttp://www.smartdraw.com/tutorials/bpm/bpm13.htm

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    Tree iagrams

    Tree Dia'rams 2 sef$ to i#entify theste&s nee#e# to a##ress the &rob$em

    Ste&s to com&$ete tree #ia'ram9

    :. 1rom the affinity #ia'ram hea#er car#s,choose the most im&ortant isse.

    haste# i#eas for ste&s.

    Tree iagram #$ample

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    Ref9

    """.smartdra".com/resources/e&am les/business/or chart'.htm

    ,rioriti2ation 9rids

    http://www.smartdraw.com/resources/examples/business/orgchart9.htmhttp://www.smartdraw.com/resources/examples/business/orgchart9.htmhttp://www.smartdraw.com/resources/examples/business/orgchart9.htmhttp://www.smartdraw.com/resources/examples/business/orgchart9.htm

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    ,rioriti2ation 9rids

    Prioriti+ation ri# 2 se# to ma)e#ecisions base# on m$ti&$e criteria

    Ste&s to com&$ete a &rioriti+ation 'ri#9:. Determine 'oa$, a$ternatives, an# criteria

    to ma)e the #ecision %ith.

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    ,rioriti2ation 9rid Steps (cont.)

    =.  "&&$y &ercenta'e %ei'ht @tota$in' to:A to each of the criteria for each

    o&tion.

    .  "## the in#ivi#a$ ratin' &er criterionto fi're overa$$ ran)in', #ivi#e by

    of o&tions to fin# avera'e ran)in'.

    . Ran) each o&tion %ith res&ect to

    criteria, avera'e ran)in's, an# a&&$ya com&$ete# ran)in'.

    ,rioriti2ation 9rid Steps (cont )

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    ,rioriti2ation 9rid Steps (cont.)

    F. M$ti&$y criteria %ei'ht by its assoc.criterion ran) for each criterion in thematri> @ is the best an# : the %orstA.Res$t in each ce$$ is ca$$e# an

    “importance score.!G.  "## im&ortance scores for each

    a$ternative.

    . Ran) a$ternatives accor#in' to

    im&ortance

    ,rioriti2ation 9rid #$amples

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    Ref9

    http://""".smartdra".

    com/tutorials/bpm/bpm

    $3.htm

    Matri$ iagrams

    http://www.smartdraw.com/tutorials/bpm/bpm10.htmhttp://www.smartdraw.com/tutorials/bpm/bpm10.htmhttp://www.smartdraw.com/tutorials/bpm/bpm10.htmhttp://www.smartdraw.com/tutorials/bpm/bpm10.htmhttp://www.smartdraw.com/tutorials/bpm/bpm10.htmhttp://www.smartdraw.com/tutorials/bpm/bpm10.htm

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    Matri$ iagrams

    Matri> Dia'rams 2 brainstormin'too$s se# in a 'ro& to sho%

    re$ationshi&s bet%een i#eas or

    isses

    Can be se# in t%o, three, or for

    #imensions

    Matri$ iagram Steps

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    Matri$ iagram Steps

    :. Determine the nmber of issesor #imensions to be se# in the

    matri>.

    .

    =. P$ace the a&&ro&riate symbo$s in

    the matri>, base# on the $e'en#.

    Matri$ iagram #$ample

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    Ref9http://""".vanderbil 

    t.edu/(ngineering/)I 

    */*loan/"eb/es$3%/qu

    ality/ne"tool.htm+ma

    tri& 

    ,rocess ecision ,rogram !harts

    http://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asphttp://www.infodesign.com.au/usabilityresources/general/affinitydiagramming.asp

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    ,rocess ecision ,rogram !harts

    Process Decision Pro'ram Charts  2 too$ to he$& brainstorm &ossib$econtin'encies or &rob$ems

    associate# %ith theim&$ementation of some &ro'ramor im&rovement

    Can be in either tree form orot$ine form

    ,, !hart Steps

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    ,, !hart Steps

    :. P$ace the first $eve$ bo>es inse(entia$ or#er.

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    Ref9

    http://""".!lo

    "bi,.com.au/!l 

    o"bi,/products

     /charter 

    'ctivity &etwor" iagrams

    http://mot.vuse.vanderbilt.edu/mt322/Affinity.htmhttp://mot.vuse.vanderbilt.edu/mt322/Affinity.htmhttp://mot.vuse.vanderbilt.edu/mt322/Affinity.htmhttp://mot.vuse.vanderbilt.edu/mt322/Affinity.htmhttp://mot.vuse.vanderbilt.edu/mt322/Affinity.htmhttp://mot.vuse.vanderbilt.edu/mt322/Affinity.htmhttp://mot.vuse.vanderbilt.edu/mt322/Affinity.htmhttp://mot.vuse.vanderbilt.edu/mt322/Affinity.htm

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    'ctivity &etwor" iagrams

     "ctivity 8et%or) Dia'rams 2 too$se# in contro$$in' &rojects

     ".K.".9 PERT @Pro'ram

    Eva$ation an# Revie% Techni(eA

    Dia'ram or Critica$5Path @$on'est

    &ath in time from be'innin' toen#A Dia'ram

    ,#8T iagram #$ample

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