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
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Management – Prof. Schmitt Exercise 07
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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.
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Management – Prof. Schmitt Exercise 07
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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)
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Management – Prof. Schmitt Exercise 07
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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.
Quality Management – Prof. Schmitt Exercise 07
Quality Function Deployment E 07 page 7© WZL/IPT
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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
Quality Management – Prof. Schmitt Exercise 07
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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?)
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Management – Prof. Schmitt Exercise 07
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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.
Quality Management – Prof. Schmitt Exercise 07
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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.
Quality Management – Prof. Schmitt Exercise 07
Quality Function Deployment E 07 page 12© WZL/IPT
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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
for a range of 1 to 10
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
Quality Management – Prof. Schmitt Exercise 07
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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.
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Management – Prof. Schmitt Exercise 07
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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 Management – Prof. Schmitt Exercise 07
Quality Function Deployment E 07 page 16© WZL/IPT
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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.
Quality Management – Prof. Schmitt Exercise 07
Quality Function Deployment E 07 page 17© WZL/IPT
Seite 17© WZL/Fraunhofer IPT
Rooftop Matrix
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
- - + + 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 - -).
Quality Management – Prof. Schmitt Exercise 07
Quality Function Deployment E 07 page 18© WZL/IPT
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Correlation Matrix
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
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
low fuel consumption 4
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.
Quality Management – Prof. Schmitt Exercise 07
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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 :
for a range of 1 to 5
for a range of 1 to 10
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
Quality Management – Prof. Schmitt Exercise 07
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Benchmark - customer evaluation
- - + + +
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
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.
Quality Management – Prof. Schmitt Exercise 07
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Benchmark - technical evaluation
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
cap base shouldermaterial profil
% 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
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Characteristics
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.
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Characteristics
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.
Quality Management – Prof. Schmitt Exercise 07
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Attachments for Exercise 07
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Management – Prof. Schmitt Exercise 07
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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
Quality Management – Prof. Schmitt Exercise 07
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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)
source: Continental AG
Quality Management – Prof. Schmitt Exercise 07
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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
source: Continental AG
Quality Management – Prof. Schmitt Exercise 07
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Seite 29© WZL/Fraunhofer IPT
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
Tyre components and their function
source: Continental AG
Quality Management – Prof. Schmitt Exercise 07
Quality Function Deployment E 07 page 30© WZL/IPT
Seite 30© WZL/Fraunhofer IPT
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
Tyre components and their function
source: Continental AG
Quality Management – Prof. Schmitt Exercise 07
Quality Function Deployment E 07 page 31© WZL/IPT
Seite 31© WZL/Fraunhofer IPT
Fabrication of tyres
source: Continental AG
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