Tyres consist mainly of: steel, rubber compound and textiles in the form of cotton. Below is a breakdown of the individual ingredients that go into the tyre:
Rubber (Natural and synthetic)
38%
Fillers (Carbon black, silica, carbon chalk)
30%
Reinforcing materials (steel, rayon, nylon)
16%
Plasticisers (oils and resins)
10%
Chemicals for vulcanisation (sulphur, zinc oxide, various chemicals)
4%
Chemicals as antioxidants to counter ozone effects and material fatigue
1%
Miscellaneous
1%
The typical composition of tyre rubber is as follows:
Number of parts containing the material
% Weight
Rubber hydrocarbon
100
51
Carbon black
50
26
Oil
25
13
Sulphur
2
1
Zinc Oxide
4
2
Other chemicals*
15
7
Includes inorganic fillers, organic vulcanisation activators and accelerators, and processing aids. (From “Opportunities and Barriers to Scrap Tyre Recycling” AEA Technology Report 1994)
So from this one can conclude that for every tonne of tyre there will be an estimated yield of 380kg of rubber and 150kg of steel. Both of which are re-usable comodities. The steel can be sold as scrap and the rubber can be used to make the many products.
A wide range of tyre wear rates can be found in literature. These wear rates have either been derived using statistical methods, or have been calculated as a result of experimental methods (for example, gravimetrical methods). Some examples are provided in the Table below.
In the Table, the first column describes the parameter that was measured, the second column shows the values obtained, the third column contains information about the method used (where stated), and the fourth column refers to the source of the information. Note that some measurements relate to tyres, whereas others relate to vehicles.
Remarks
Value / Range
Method used
Source
Average tyre wear rate for front-wheel drive (fwd) car
79 mg/vkm
Gravimetrical measurement of tyre wear by weighing the tyres of 5 test vehicles (4 front-wheel drive and 1 rear-wheel drive) after predefined periods of use.
Warner et al. (2002)
Average tyre wear rate for rear-wheel drive (rwd) car
193 mg/vkm
Average tyre wear for a vehicle
97 mg/vkm
Average tyre wear rate of a front tyre for the fwd vehicles
28 mg/tyre/km
Average tyre wear rate of a rear tyre for the fwd vehicles
8 mg/tyre/km
Average tyre wear rate of a front tyre for the rwd vehicle
50 mg/tyre/km
Average tyre wear rate of a rear tyre for the rwd vehicle
47 mg/tyre/km
Estimated tyre wear rate
30 mg/tyre/km
-
G ttle (1979)
Estimated tyre wear rate
30 mg/tyre/km
-
Malmqvist (1983)
Estimated tyre wear rate
60-90 mg/tyre/km
-
Dannis (1974); Schuring and Clark (1988)
Estimated tyre wear rate
50 mg/tyre/km
-
Baekken (1993)
Estimated tyre wear rate
16 mg/tyre/km
-
Lee et al (1997)
Estimated tyre wear rate for light vehicles
17 mg/tyre/km
Estimation of wear for typical tyres using manufacturer information
Legret and Pagotto (1999a)
Estimated tyre wear rate for heavy vehicles (>3.5t)
34 mg/tyre/km
Passenger car tyre wear rate
53 mg/vkm
-
Gebbe (1997)
Light duty vehicle tyre wear rate
110 mg/vkm
Heavy duty vehicle tyre wear rate
539 mg/vkm
Motorbike tyre wear rate
26.4 mg/vkm
Passenger car tyre wear rate
120 mg/vkm
-
CARB (1993)
Passenger car tyre wear rate
80 mg/vkm
-
Baumann (1997)
Heavy duty vehicle tyre wear rate
189 mg/vkm
Articulated lorry tyre wear rate
234 mg/vkm
Bus tyre wear rate
192 mg/vkm
Passenger car tyre wear rate
163 mg/vkm
-
SENCO (1999)
Wear rate for trucks
1403 mg/vkm
Light duty vehicle tyre wear rate
53 mg/vkm
-
EMPA (2000)
Heavy duty vehicle tyre wear rate
798 mg/vkm
Passenger car tyre wear rate
64 mg/vkm
-
Garben (1997)
Light duty vehicle tyre wear rate
112 mg/vkm
Heavy duty vehicle tyre wear rate
768 mg/vkm
Motorbike tyre wear rate
32 mg/vkm
Tyre wear for vehicles (<1400cc)
36 mg/vkm
Gravimetrical measurement of tyre wear by weighing 21 tyres
Kolioussis and Pouftis (2000)
Tyre wear for vehicles (1400-2000cc)
40 mg/vkm
Tyre wear for vehicles (>2000cc)
46 mg/vkm
Average estimated tyre wear
40 mg/vkm
The table shows that tyre wear rates range from 40 to 300 mg/vkm. This variation is probably due to differences in tyre construction, road surface characteristics, driving conditions and vehicle load, as well as tyre position on the vehicle. It may also be due to uncertainties associated with the various estimation procedures.
What are tyres made of?
Tyres consist mainly of: steel, rubber compound and textiles in the form of cotton. Below is a breakdown of the individual ingredients that go into the tyre:
The typical composition of tyre rubber is as follows:
Includes inorganic fillers, organic vulcanisation activators and accelerators, and processing aids.
(From “Opportunities and Barriers to Scrap Tyre Recycling” AEA Technology Report 1994)
So from this one can conclude that for every tonne of tyre there will be an estimated yield of 380kg of rubber and 150kg of steel. Both of which are re-usable comodities. The steel can be sold as scrap and the rubber can be used to make the many products.
A wide range of tyre wear rates can be found in literature. These wear rates have either been derived using statistical methods, or have been calculated as a result of experimental methods (for example, gravimetrical methods). Some examples are provided in the Table below.
In the Table, the first column describes the parameter that was measured, the second column shows the values obtained, the third column contains information about the method used (where stated), and the fourth column refers to the source of the information. Note that some measurements relate to tyres, whereas others relate to vehicles.
The table shows that tyre wear rates range from 40 to 300 mg/vkm. This variation is probably due to differences in tyre construction, road surface characteristics, driving conditions and vehicle load, as well as tyre position on the vehicle. It may also be due to uncertainties associated with the various estimation procedures.