07 Quality Function Deployment Dipl.-Ing. Christoph Hammers · Quality Function Deployment E 07 page 0 ... Time until pizza is delivered: Question: Less than 30 min.? Antwort: Thats

Quality Management – Prof. Schmitt Exercise 07

Quality Function Deployment E 07 page 0© WZL/IPT

© WZL/Fraunhofer IPT

Exercise Quality Management07 Quality Function Deployment

Dipl.-Ing. Christoph Hammers

Dipl.-Ing. Christoph HammersGroup Business Excellence & Development Department Quality ManagementChair of Metrology and Quality ManagementSteinbachstr. 25 (ADITEC), D-52074 Aachen, Tel.: +49 (0)241 80-26977Fax: +49 (0)241 80-22671 Email: [email protected]: http://www.wzl.rwth-aachen.de



Seite 1© WZL/Fraunhofer IPT

Customer Statements - Examplesquiet solidfragile coverreliable affecting apparatuscut off connections or the refusal of the commands are only two follows of its pettish attitudeI once switched it on in the cinema and I nearly went blinddisoriented softwaregood apparatus, good freaky functionsdull sounddistorted soundspongy keyboardweak keyboardit does not sound strange when you squeeze it, not like it couldbe damaged easily after the first downthrow the display went crazy and you could not use it any longer




Customers Need

Identifikation of Critical Customer Requirements

Specific Measurable CriteriumCustomers ExpectationsReal Customer Statements

All required packages/ patchescontained in the installation file.

Software is 100% compatible to customers IT-System.

The software doesn‘t work the way the salesman has promised.

These Software doesn‘t workproperly.

No further choices to be made on a (telephone) menu.

Customer is connected to theresponsible serviceman within 30 sec.

Wants to speak to a servicemanI‘ll talk to the serviceman right now. I won‘t accept waiting any longer.

Chainsaw starts with second pull of the starter rope

Chainsaw starts with a power of XY N pulling on the rope.

Want to start the chainsaw fast.The chainsaw shall be easy to start.

The rope shall be pullable with lesspower.

Voice of Customer (VOC) Critical Customer Requirement (CCR)

Identification of critical Customer RequirementsThe translation of the customers voice into measurable specific product characteristics is essential for product development.For customer oriented development the critical characteristics have to be identified and target values to be defined.




Kano-Model

TIME

Cus

tom

ersa

tisfa

ctio

n

Fulfilment ofrequirements

dynamic navigation system

“Must-be”/ Basic requirementsQuality and performance requirements

delighting characteristics

low fuel consumption

airbags




Determination of Product Characteristics which delighterCharacteristics:

– The product characteristics are valuable for the customer– They are unknown to the customer.

Determination: – Careful choice of target groups (Interviews with single

persons or small groups) – The specific topics are mostly unknown– Essential are:

Open minded users who can imagine to use alternative services, products or a combination of both. (extern)creative engineers with a strong comprehension of

feasible concepts. (intern)




Application of the Kano-Model: Determination of Critical CustomerRequirements (CCR)

Field of application:– Determination which products or services are (not) esteemed

by the customer. – Validation of critical customer requirements.

Approach: – Specific questioning of the customer regarding special

characteristics or requirementsAssessment of the fulfilment of a requirementAssessment of thenon-fulfillment of a requirement

– Structuring thestatements into:Delightment („I‘m loving it“)Expectation („That goes without saying!“)Indifference („I‘m not sure“)Dislike („I don‘t like it“)

Time




dislike

indifference

Expect.

delight

fulfilment

dislikeindifference

expectation

delight

Non-fulfilment

Application of the Kano-ModelCharacteristic which delight thecustomer

Quality- and Performance characteristic/ requirement

Basic characteristic/ must-berequirement

Quality Characteristic withpotential for improving throughsubstitution by othercharacteristics.

„Bad idea“ or reason fordissatisfaction with the product.

Customer statement isinappropriate.




dislike

indifference

expect

delight

Fulfilment

dislike

indifference

expect

delightg

Non-fulfilment

Application of the Kano Model – An ExampleTime until pizza is delivered:

Question: Less than 30 min.?Antwort: Thats normal.Frage: More than 30 min.?Antwort: Thats not acceptable.

– A waiting time of more than 30 min. will not be accepted.

Question: Less than 15 minutes?Antwort: I‘ll be delighted.Frage: More than 15 min.?Antwort: Thats normal.

– A waiting time of less than 15 min is a characterictic whichdelights the customer.

To be evaluated:– How is the influence on costs if characteristic is a delighter– Is the´market attractivness high enough under consideration

of monetary matters?dislike

indifference

expect

delight

Erfüllung

dislikeindifference

expectdelightg

Nichterfüllung

12

1

2




Determination ofCustomer Requirements

1

Correlationsbetween different

Quality Characteristics

3

Assessing the correlationbetween Customer Requirements

and Quality Characteristics

4

House of Quality - Procedure

What?

Selection of importantQuality Characteristics

2

How?

Ranking theQuality Characteristics

5

How much?

Derivate new target valuesand other figures

6

Why?

House of Quality – Procedure:1. Determination of Customer Requirements (What?)2. Selection of important Quality Characteristics (How?)3. Correlations of the different Quality Characteristics 4. Assessing the correlation between Production Requirements and Quality Characteristics5. Ranking the Quality Characteristics (How much?)6. Derivate new target values and other figures (Why?)




Four phases after ASI - American Supplier Institute

closing force [Fs]

extruder speed [n]

controller

pressing pressure [pd]

Easy-to-close doors

10N

Product planning

. . .

Pressing pressure

30

Process planning

. . .

Extruder speed [n]

250

Production planning

. . .

Closing force [Fs]

7

Sealing

Nmm²

Component planning

. . .

1min

Clo

sing

forc

e [F

s]

Pre

ssin

g pr

essu

re [p

d]

Ext

rude

r spe

ed [n

]

Con

trolle

r




1 6. .

CR: Customer RequirementsQC: Quality Characteristics

Customer Requirements

Directionof improvement

QualityCharacteristics

2

Correlationbetween

CR and QC

4

5

Cus

tom

erev

alua

tion

Ben

chm

arki

ng(C

usto

mer

view

)

Benchmarking(Technical

view)6

6

6Steps for developing aHouse of Quality

House of Quality - Structure

Impo

rtanc

e

Cus

tom

erR

equi

rem

ents1

Important qualitycharacteristics

Correlation

3

Techn. difficultyTechn. evaluation

Quality Function Deployment (QFD)House of Quality – Structure:Today the House of Quality is one of the most commonly used tools for implementing Quality Function Deployment, providing a combination of various matrices, lists and tables, to support the individual transformation steps in QFD process. The conversion of Customer Requirements into Quality Characteristics is supported and evaluated by using weighted relations to link the contents of various matrices and tables.




The tyre should be rain capableThe tyre should have good emergency running propertiesThe tyre shouldn‘t cause too much noiseThe tyre should provide low fuel consumptionThe tyre should have a high durabilityThe tyre should have a sportive handling

Determination of Customer Requirements

Customer Requirements:

Application of the QFD MethodDetermination of Customer Requirements:The QFD Method will be used for designing a car tyre. At first a primary evaluation in form of an inquiry is accomplished.The results of an exemplary inquiry are shown on the above.




Handout: Pair-wise comparison

...

...

...

requirement B

requirement A

Customer requirements

0

requ

irem

entA

2re

quire

men

tB

wei

ghtG

i

sum

S i

...

„A“ more important than „B“inscribe „2“

Matrix field for inscriptionof the lines summation.

„B“ less important than „A“Inscribe „0“

Pair-wise comparisonAt first the QFD weightings are determined with the help of a pair-wise comparison of all requirements which have resulted from the inquiry. In the following all Customer Requirements in the matrix are compared with each other.If a Customer Requirement (e.g. “A” from line 1) is more important than the associated requirement in the pair (“B” from column 2) a 2 has to be inscribed in the appropriate matrix array. In case of the same importance a 1, in case of less importance a 0 has to be inscribed. To get the weighted Customer Requirements use the following formulas:

for a range of 1 to 5


Wi : weight; Si : sum of correlating line; Smax : maximum line sum;Smin : minimum line sumLast but not least the weighted Customer Requirements are inscribed into the House of Quality.

⎟⎟⎠

⎞⎜⎜⎝

⎛+

−−

⋅= 14minmax

min

SSSSRdW i

i

⎟⎟⎠

⎞⎜⎜⎝

⎛+

−−

⋅= 19minmax

min

SSSSRdW i

i




Exercise: Pairwise ComparisonA customer survey provides the following information to you:

The tyres‘ rain capability is more important than low noise emission or low fuelconsumtion.

The good emergency running capabilities are as same important as high speed capabilityan a sportive handling.

Just the rain capability is more important than a low fuel consumption.

Low noise emission is more important than good emergency running capabilities, a sportive handling and high speed capability but less important than the otherrequirements.

High durability is as same important as sportive handling.

Calculate the weight of each customer requirement by the use of the pairwise comparison.




Excercise: Comparison in Pairs

high-speed capable

low fuel consuption

low noise

good emergency running properties

rain capable

customer requirements rain

capa

ble

good

em

erge

ncy

runn

ing

prop

ertie

s

low

nois

e

low

fuel

cons

uptio

n

high

-spe

edca

pabl

e

high

dur

abili

ty

wei

ghtW

i

sum

S i

high durability

sportive handling

spor

tive

hand

ling




House of Quality

Product B

Product A

Strong PositivePositive

Negative Strong Negative

Directionof Improvement

MaximumNeutral Minimum

++

--Strong Correlation = 9

= 3

= 1

Benchmarking- Customer View- Technical Evaluation

+-

Medium Correlation

Weak Correlation

cust

omer

eval

uatio

n

cap base shouldermaterial profil

customer requirements

importance % s

ilica

% fl

exib

ilise

r

quot

aof

trea

dde

epen

ings

tread

dept

h

dens

ety

hard

ness

angl

e

hard

ness

cust

omer

eval

uatio

n

rain capable 5

1 2 3 4 5 6

good emergency runningprosperties 1

low noise 3

low fuel consumption 4

high-speed capable 1

high durability 3

sportive handling 1

15% 10% 7% 6mm0,8

kg/dm390o

Shore A 10o 85o

Shore A

123456

69 75 94 78 51 43 6 107 8 10 8 6 5 1 1

technical evaluations

target values

absolute importanceimportance 1-10

- - + + +

qual

ity-

char

acte

ristic

s

Case study “car tyre”: Completely elaborated House of QualityThe picture shows the QFD on the production level by the example of a car tyre. The proceeding differs from the ASI concept and shows that the QFD works as a flexible instrument. In the first House of Quality (HoQ) of this example it is not possible to name target values because the components can’t be defined in physical values. Therefore it is not possible to identify the direction of improvement and to sign in the matrix of the rooftop.This HoQ analyses the influence of Customer Requirements on the product components.

Example – Planning of ComponentsThe HoQ of the car tyre shows that the technical parameter “tread pattern” is related to most of the Customer Requirements. Now this parameter will be shown in detail. The detailed view could also have been achieved in the very first HoQ, but then it wouldn’t have been that clearly arranged. It has to be decided individually which procedure is suited best regarding time, profit and usage.The HoQ concerning the tread pattern offers the possibility to plot the target values, the direction of improvement and the matrix of the rooftop.




Quality Characteristics of the component “tread pattern”

cap-material: % silicacap-material: % flexibilisercap-profile: share of negative tread (profile)cap-profil: profile depthbase: densitybase: hardnessshoulder: angleshoulder: hardness...

Quality Characteristics:

Identification of Quality Characteristics (QC)In the following work step the Quality Characteristics of the tread pattern will be identified. They represent measurable criteria for the fulfilment of the Customer Requirements and can be used for the technical implementation.




Rooftop Matrix

cust

omer

eval

uatio

n



importance % s

ilica

% fl

exib

ilise

r

quot

aof

trea

dde

epen

ings

tread

dept

h

dens

ety

hard

ness

angl

e

hard

ness

cust

omer

eval

uatio

n

rain capable 5

1 2 3 4 5 6

good emergency runningprosperties 1

low noise 3


high- speed capable 1

high durability 3

sportive handling 1

15% 10% 7% 6mm0,8

kg/dm390o

Shore A 10o 85o

Shore A

123456

69 75 94 78 51 43 6 107 8 10 8 6 5 1 1


target values

absolute importanceimportance 1- 10

- - + + qu

ality

-ch

arac

teris

tics

shouldermaterial profile

cap base

% s

ilica

% fl

exib

ilise

r

Quo

taof

trea

dde

epen

ings

tread

dept

h

dens

ity

hard

ness

angl

e

hard

ness

- - + +

Rooftop MatrixThe Rooftop Matrix is used for the identification of interactions between the various Quality Characteristics.These can be of different characteristic:- Strong Positiv interaction ++- Positiv interaction +- Neutral no inscription- Negative interaction -- Strong negative interaction --

Example:Silica and flexibiliser are both parts of the cap material. The procentual quota of the flexibiliser should stay the same but the quota of silica should be raised. Because the material is a mixture of both a procentualchange of one part influences the quota of the other part which means there is a strong negative interaction (shown by - -).




Correlation Matrix

cust

omer

eval

uatio

n



importance

% s

ilica

% fl

exib

ilise

r

quot

aof

trea

dde

epen

ings

tread

dept

h

dens

ety

hard

ness

angl

e

hard

ness

cust

omer

eval

uatio

n

rain capable 5

1 2 3 4 5 6

good emergency runningprosperties

1

low noise 3



high durability 3

sportive handling 1

15% 10% 7% 6mm0,8

kg/dm390o

Shore A 10o 85o

Shore A

123456

69 75 94 78 51 43 6 107 8 10 8 6 5 1 1


target values


- - + + +

qual

ity-

char

acte

ristic

s

Customer requirements

importance % s

ilica

% fl

exib

ilise

r

quot

aof

trea

dde

epen

ings

tread

dept

h

dens

ety

hard

ness

angl

e

hard

ness

rain capable 5

good emergency runningproperties 1

low noise 3


high-speed capable 1

high durability 3

sportive handling 1

... ... ... ... ... ... ... ...

69 75 94 78 51 43 6 107 8 10 8 6 5 1 1

Absolute importanceImportance 1-10

Qua

lity

ch

arac

teris

tics

Symbols are used for documenting the correlation between Customer Requirements and Quality Characteristics in the matrix. Three intensity levels are distinguished when using the tabular description. A circle with a dot in the middle stands for a very strong coherence. For the calculation of the characteristic importance a numeric value of 9 is used.A medium strong coherence is represented by simple circles (value: 3).Triangles are used to point out a weak correlation (value: 1).Usually the correlations are determined during a discussion of experts from all concerned business divisions like design, planning, construction, manufacturing, assembly and quality assurance. According to that only a relatively rough gradation can be used when evaluating the correlations. The term “intensity of coherence” is comparable to the term “intensity of correlation”, which is used in the fields of statistics. Than the absolute and the relative importance can be calculated. The absolute importance is calculated by summing up the product of the weight and the value of correlation within a column. The relative importance can be calculated analogue to the calculation of the weight used for the pair wise comparison. (See next page)Exercise: Calculate the absolute and relative importance of the quality characteristics.




This page stays empty for technical reasons

A strong connection exists, if the change of a Quality Characteristic leads to a systematic change of the customer satisfaction (in the sense of the fulfilment of a certain Customer Requirement). The algorithm for calculating the absolute importance of Quality Characteristics can be described as the following:Importance of the first Customer Requirement (CR#1) multiplied with the correlation to the first Quality Characteristic (QC#1) plus the importance of CR#2 multiplied with the correlation to QC#1 plus CR#3 x QC#1 plus .... This proceeding has to be repeated for every column (quality characteristic).The relative importance is calculated analogue to the pair-wise comparison :



Wi : weighting; Si : sum of correlating line; Smax : maximum line sum; Smin : minimum line sum

⎟⎟⎠

⎞⎜⎜⎝

⎛+

−−

⋅= 19minmax

min

SSSS

RdW ii

⎟⎟⎠

⎞⎜⎜⎝

⎛+

−−

⋅= 14minmax

min

SSSSRdW i

i




Benchmark - customer evaluation

- - + + +

cust

omer

eval

uatio

n



importance

% s

ilica

% fl

exib

ilise

r

quot

aof

trea

dde

epen

ings

tread

dept

h

dens

ety

hard

ness

angl

e

hard

ness

cust

omer

eval

uatio

n

rain capable 5

1 2 3 4 5 6


1

low noise 3



high durability 3

sportive handling 1

15% 10% 7% 6mm0,8

kg/dm390o

Shore A 10o 85o

Shore A

123456

69 75 94 78 51 43 6 107 8 10 8 6 5 1 1


target values


Customer Requirements

Importance Cus

tom

erev

alua

tion

rain capable 5 ... 1 2 3 4 5 6

good emergency runningproperties 1 ...

low noise 3 ...

low fuel consumption 4 ...

high-speed capable 1 ...

high durability 3 ...

sportive handling 1 ...

Benchmark Customer View – Technical ViewAn additional goal of using QFD in product planning is to determine target values for a detailed development. For this the Quality Characteristics and the Customer Requirements have to be investigated accurately by regarding realisation possibilities and their respective market potential.The way which is usually taken to find out a solution is to compare products directly (benchmarking) and to survey customers about how the regarded products fulfil their expressed requirements.So the HoQ has to be completed by a customer based and a technical based comparison. Such comparisons in QFD mostly use an integer scale from 1 (“particularly well“ resp. “fulfilled“) to 6 (“particularly bad“ resp. “not fulfilled“). The results of a customer survey and a technical comparison are displayed above and on the following page.




Benchmark - technical evaluation

cust

omer

eval

uatio

n



importance

% s

ilica

% fl

exib

ilise

r

quot

aof

trea

dde

epen

ings

tread

dept

h

dens

ety

hard

ness

angl

e

hard

ness

cust

omer

eval

uatio

n

rain capable 5

1 2 3 4 5 6


1

low noise 3



high durability 3

sportive handling 1

15% 10% 7% 6mm0,8

kg/dm390o

Shore A 10o 85o

Shore A

123456

69 75 94 78 51 43 6 107 8 10 8 6 5 1 1


target values


- - + + +

qual

ity-

char

acte

ristic

s


% s

ilica

% fl

exib

ilise

r

quot

aof

trea

dde

epen

ings

tread

dept

h

dens

ety

hard

ness

angl

e

hard

ness

... ... ... ... ... ... ... ...

15% 10% 7% 6mm0,8

kg/dm390o

Shore A 10o 85o

Shore A

123456

Technical evaluation

Target values




Process planning cap – third phase (ASI)

Importance 1 - 10

Target values

8Tread depth

10Quota of tread deepenings

8% Flexibiliser

7% Silica

Absolute importance

Vul

cani

zing

furn

ace

Ext

rude

r

Ble

nder

Impo

rtan

ce

16297135

6 1 10

Process Steps


Process planningThe HoQ of process planning determines the correlation between process steps and Quality Charactericsof the components. Analogue to the very first HoQ it is not possible to set up target values or the direction of improvement. A filling in of the rooftop matrix is also not feasible.




Production planning extruder – fourth phase (ASI)

Absolute importance

Target values

8tread depth

10quota of tread deepenings

8% flexibiliser

7% silica

Direction of improvement

tread

mill

spee

d

wid

thof

die

heig

htof

die

revs

tem

pera

ture

Impo

rtan

ce

80°C 70/ min

15mm

25mm/s

87 15 82 54 72

--

++

200mm

10

Importance 1 - 10 10 2 9 54 81

Setting Parameter


Production planningThe production planning provides the correlation between the setting parameters and the Quality Characteristics of the components. This HoQ can be filled in completely. Another thinkable possibility might be to combine the third and fourth house in only one House of Quality.




Attachments for Exercise 07




KX

X/X.

03

1 rubber 38%(natural- and synthetic rubber)

2 fillers 30%(soot, silica, chalk, ...)

3 reinforcements 16%(steel, rayon, polyester, nylon)

4 flexibiliser (oil, resin, ...) 10%

5 vulcanising materials(sulphur, zinc oxide, ...) 4%

6 several chemicals 1%(wax, antioxidants, ...)

7 miscellaneous 1%

Tyre materials

source: Continental AG




KX

X/X.

03

The structure of a tyre

Cap: tread and mixture influence the characteristics

Base: cuts the rolling resistance

Nylon overlays: increase the high speed capability Steel belt: increases the driving stabilityCarcass: relevant for form and stability of the tyreInner layer: gas proof inner layer replaces the tubeSide frame: protects carcass against damaging and atmos-pheric influencesCore profile: used for steering precision and driving stability. Influences the comfort

Core: ensures a solid fit on the rim

Chipper: for precise steering and a high driving stability source: Continental AG




conventional tyre

rubber/rubber-contact of the side causes a fast destruction of the tyre.

RFT tyre

TPMS

Inserts

Insert-profiles in the side panel carry the load in case of loss of pressure und avert the rubber / rubber-contact.

Run Flat Tyres (RFT)





1/2 tread pattern

3 nylon overlays

4 steel belt

synthetic- and natural rubber mixtures

Cap ensures grip, abrasion resistance, driving stability and stopping performance

Base reduces the rolling resistanceShoulder constitutes an optimal transition from the

tread pattern to the side panel

rubber covered nylon

ensures high speed stability

steel belt of high tensile strength

ensures form- and driving stabilityreduces the rolling resistanceincreases the driving performance

Tyre components and their function





6 inner layer

Rubber covered rayon or polyester

ensures dimensional stability and averts inflation

butyl rubber mixture

ensures airproofness

nature rubber mixtures

Influences the driving comfortprotects against lateral damagesaverts ageing damages (ozone, UV-radiation)

5 fabric layer

7 side frame






8 core profile

9 core

10 chipper

synthetic rubber mixture

ensures driving stabilityincreases the precision of steeringInfluences the driving comfort

rubber covered steel wire

ensures tight fit on the rim

Rubber covered rayon or nylon

ensures driving stabilityincreases the precision of steeringensures durability






Fabrication of tyres


inner layercalendering

tread pattern-extrusion

woven textilecalendering

Core winding

tread pattern-cut

layer-cut

belt-cutbead filler-

application

rubber chemicalsMixing facilities

Steel beltcalendering

side frame-extrusion

carcass-manufacture

blank-manufacture

visualinspection

uniformity measuring

heating

07 Quality Function Deployment Dipl.-Ing. Christoph Hammers · Quality Function Deployment E 07 page 0 ... Time until pizza is delivered: Question: Less than 30 min.? Antwort: Thats

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