Continental Car Tyres - Tyre Basics

 Tyre Basics Passenger Car Tyres

2005/06

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 Tyre Basics - Passenger Car Tyres

 Tyre Basics - Passenger Car Tyre Tyres s

Materials used in a tyre

Tyre Components

The components of a modern radial tyre for passenger cars contain diverse ingre-

1

dients in differing amounts.

2

These ingredients vary by tyre size and tyre type (summer or winter tyre). The example below shows the ingredients

3

4

5

used in the summer tyre 205/55 R 16 91W

6

ContiPremiumContact

(The tyre shown here weighs about 9.3 kg

7

without the rim). Tyre example: ContiPremiumContact,

9

8

205/55 R 16 91W.

Every modern passenger car tyre has a complex structure

 A modern tyre is made up of:

1

Breakdown of ingredients

2

Rubber (nat (n atur ural al an and d syn synth thet etic ic ru rubb bber er)) Fillers (carbon black, silica, carbon, chalk …)

Tread/belt assembly Tread/belt consisting of

41% 41 %

Reinforcing materials (steel, rayon, nylon) Plasticizers (o (oils an and re resins)

5

Chemicals for vulcanisation (sulphur, zinc oxide, various other chemicals)

3

1

6

7

7 6

Jointless cap plies – enable high speeds

3

Steel-cord belt plies – optimise directional stability and rolling resistance

4

Textile cord ply – keeps the tyre in shape even with high inflation pressure

5

Inner liner – makes the tyre airtight

6

Side wall – protects from lateral damage

7

Bead apex – promotes directional stability, steering performance and comfort level

8

Bead core – ensures firm seating on the rim

9

Bead reinforcement – promotes directional stability and precise steering response

6%

6%

4 5

2

15%

2 4

Tread – for good road grip and water expulsion

30% Casing, consisting of

3

1

Chemicals as antioxidants (to counter ozone effects and material fatigue)

1%

Miscellaneous

1%

The functions of the individual components are explained on the next two pages.

 Tyre Basics - Passenger Car Tyres

 Tyre Basics - Passenger Car Tyre Tyres s

Components and Their Functions  Tread/Belt  T read/Belt Assembly  1

 Tread

Material

Synthetic and natural rubber

Functions Cap

s

Cap: Ca p:

Inner liner

Material

Butyl rubber

Functions

prov pr ovid ides es gr grip ip on al alll roa road d sur surfa face ces, s,

s

wear-resistance and directional

s

Seals the air-filled inner chamber  Acts as a tube in modern tubeless tyres

stability

Base

Shoulder

5

s

Base:

reduces rolling resistance and

s

Shoulder: forms an optimal transition from

damage to the casing the tread to the sidewall

6

Side wall

Material

Natural rubber

Functions

2

Start End

Jointless cap plies

Material

s

Protects the casing from lateral damage and atmospheric conditions

Nylon, embedded in rubber

Functions s

Enhances high-speed suitability

7

Bead apex

and manufacturing precision Material

Synthetic rubber

Functions

3 0.3 mm

Steel-cord for belt plies

Material

High-strength steel cords

s

Enhances directional stability

s

Gives steering precision

s

Improves comfort

8

Bead core

Functions

Enhances shape retention

Material

and directional stability

Functions

s

Reduces the rolling resistance

s

s

Increases the tyre’s mileage performance

s

Carcass

4

 Textile cord ply 

Material

Rayon or polyester (rubberised)

Functions s

Contains the tyre’s inflation pressure

9

Steel wire embedded in rubber

Ensures that the tyre sits firmly on the rim

Bead reinforcement

Material

Nylon, aramid

Functions s

Enhances directional stability

s

Gives steering precision

 Tyre Basics - Passenger Car Tyres

 Tyre Basics - Passenger Car Tyre Tyres s

 Tyre Production - A Glance Around the Factory  Supplier industry 

Compound production 5

Manufacture of  Semi-finished products Steel cord

Vulcanisation

Building Putting together the individual components of a tyre

11

6

Quality   control

12

13

pre-treatment of the “green” tyre

final visual inspection

1

steel industry (steel cord, steel  wire)

rubber portioning

stee st eell-co cord rd spoo spools ls

Tread

stee st eell-co cord rd cale calenndering

cutting steel-cord to size

con tr tr ol ol of of we wei gh ght per metre

tread cooling

building of the casing

7

2 portioning of raw materials and supplies chemical industry (synthetic rubbers, additives)

3

tr ea ead ex ext ru ru de der

Textile-cord

production of master batch

control of unit  weight

building of the tread/belt assembly

 X-ray control

8

cord fabric on rollers

Steel bead

cutting the tread to size

textile-cord calendering

cutting textile-cord to size

 vulcanisation

check for imbalance

9

rubber extraction (natural rubber)

making up of production compound

4

unwinding of bead wire

Sidewall/inner liner

coating of bead  wire

rewinding of bead wire

bead ring

applying the apex

force variation control

10 Each individual stage of production – from the inspection of the raw materials through to delivery of the finished tyre – is subject

textile industry (various cords)

to ongoing quality control. shaping into transportable units

sidewall extrusion

calendering of the inner liner

 Tyre Basics - Passenger Car Tyres

 Tyre Basics - Passenger Car Tyre Tyres s

 The tyre viewed from the outside

Sidewall Markings – Standard and Required By Law 1

Manufacturer (trademark or logo)

2

Product name

3

Size designation 205 = Tyre width in mm 55

16

8

3

1

in percent

17

4

4

14

7

13

10

R

= Radi Radial al constr constructi uction on

16

= Rim diameter in inches (code)

91

= Load index

 V

= Speed index

(see also page 22)

15

9

= Height-to-width ratio

18

SSR = Special designation SSR

for runflat tyres

19

( Self Supporting Runflat)

5

to countries outside Europe: 12 Country of manufacture 13 U.S. load index for max.

Load Rating (615 kg per wheel = 1356 lbs.) where 1 lb. = 0.4536 kg 14 Tread ad:: beneath which there

are 4 plies s

(see also page 22) 5

20

 All other information applies

1 nylon ply Sidewall: the tyre casing consists of s

Tubeless

51 psi (1 bar = 14.5 psi)

7

Continental tyres are marked in

USA: tyre manufacturer’s guarantee

accordance with international regula-

for compliance with certain quality

tions. So the sidewall is marked with

characteristics on the basis of

a circle containing an E and the

standardised tests conducted on

number of the country of homolo-

reference tyres as determined by law

gation. This marking is followed by a

16

11 2

multi-digit homologation number, 8  Approval number as per ECE R 30 9

10

 Abbreviations Transportation

ECE

= Economic Commission for

Brussels

Tem empe pera ratu ture re::  A, B or C =

wet braking capability of the tyre

s

Date of manufacture (week/year)

temperature stability of the tyre

2205 means the 22nd week of

at higher test speeds. C is

2005

sufficient to meet U.S. statutory

Department of Transportation

requirements

(U.S. department which oversees

19 Iden Identifi tificatio cation n for Bras Brasil il

tyre safety standards)

20 Iden Identifi tificatio cation n for Chin China a

T.W.I.: Tread Wear Indicator. Bar-like

longitudinal tread grooves which appear once tread depth wears down

(U.S. safety code)

18

Tyre factory, tyre size and type

protuberances at several points of the

Standards

Tra ract ctio ion: n: A, B or C =

s

(UN institution in Geneva) Vehicle le Safety Safety FMVSS = Federal Motor Vehic

standard U.S. testing 17

Manufacturer’s code:

Europe

ETRTO = European Tyre and Rim

Technical Organisation,

11

Tre read adwe wear ar:: relative life

expectancy of the tyre based on

e. g. E4 (4 = Netherlands)

12

= U.S. Department Department of

1 rayon ply

15 U.S. limit for max. inflation pressure

6

6

DOT

1 rayon ply, 2 steel belt plies,

to 1.6 mm (see also page 21)

 Tyre Basics - Passenger Car Tyres

 Tyre Basics - Passenger Car Tyre Tyres s

 Wheels and Rims Rim + wheel nave = disc wheel

The following points must be observed when fitting tyres to rims: tyre and rim

For modern vehicle construction, the rim

must correspond in terms of diameter, and

offset is crucial. For this reason it may be

must be approved in that combination

altered only slightly, even if changes are

for the vehicle type. It is essential that the

made in the axle geometry.

rims used are dimensionally accurate, clean and rust-free, and neither damaged

The rim offset (mm) is the distance

nor worn.

measured from the centre of the rim of a disc wheel to the inside contact face of the wheel disc, where it presses against the

There are several rim contours:

hub flange. This value can be either

s

1. Drop centre rim (normal)

positive or negative.

s

2. Hump rim = safety contour

s

3. Ledge rim = safety contour

Thanks to slight curvatures, rims 2. and 3. guarantee the tubeless tyre sits firmly on the rim. Indeed, such rims are absolutely essential for tubeless radial tyres.

Passenger car hump rim

Rim width Tapered seat

Hump

Flange

Drop centre

Diameter

Example: 6 1/2 J x 16 H2 B ET 45

(to DIN 7817) 6 1/2

Rim width (in inches)

J

Flange type

 X

Drop centre

The hump rim is a modern drop centre rim

16

Diameter (in inches)

of the kind used on bicycles, motorcycles,

H2

Double hump

passenger cars, agricultural and other

 Asymmetrical drop centre

commercial vehicles. The drop centre is

Rim offset in mm

necessary in fitting the tyre on the rim.

B ET45