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Document Origin: http://www.rma.org/scrap_tires/scrap_tire_markets/scrap_tire_characteristics/

 

1. Typical Materials Composition of a Tire
2. Typical Composition by Weight
3. Densities of Shredded and Whole Tires
4. Rubber weight by tire component.
5. Steel Tire Cord Analysis

1. Typical Materials Composition of a Tire

This table lists the typical types of materials used to manufacture tires.

Typical Composition of a Tire Synthetic Rubber Natural Rubber Sulfur and sulfur compounds Silica Phenolic resin Oil: aromatic, naphthenic, paraffinic Fabric: Polyester, Nylon, Etc. Petroleum waxes Pigments: zinc oxide, titanium dioxide, etc. Carbon black Fatty acids Inert materials Steel Wire

 

2. Typical Composition by Weight

This lists the major classes of materials used to manufacture tires by the percentage of the total weight of the finished tire that each material class represents.

Passenger Tire

Natural rubber	14 %
Synthetic rubber	27%
Carbon black	28%
Steel	14 - 15%
Fabric, fillers, accelerators, antiozonants, etc.	16 - 17%
Average weight:	New 25 lbs, Scrap 20 lbs.

 

Truck Tire

Natural rubber	27 %
Synthetic rubber	14%
Carbon black	28%
Steel	14 - 15%
Fabric, fillers, accelerators, antiozonants, etc.	16 - 17%
Average weight:	New 120 lbs., Scrap 100 lbs.

3. Densities of Shredded and Whole Tires

APPROXIMATE DENSITIES LOOSELY PACKED   DENSELY PACKED 550-600 lbs/yd3 single pass 1220-1,300 lbs/yd3 850-950 lbs/yd3 2" shred 1,350-1,450 lbs/yd3 1,000-1,100 lbs/yd3 1 1/2" shred 1,500-1,600 lbs/yd3 100/10Yd3 WHOLE TIRES (PASSENGER/LIGHT TRUCK) 500/10Yd3     10 MESH- 29 lbs/ft3 20 MESH- 28 lbs/ft3 30 MESH- 28 lbs/ft3 40 MESH- 27 lbs/ft3 80 MESH- 25-26 lbs/ft3

4. Rubber weight by tire component.

A tire is manufactured from several separate components, such as tread, innerliner, beads, belts, etc. This table shows which components account for the rubber used to make the tire.

RUBBER PERCENT BY WEIGHT IN A NEW RADIAL PASSENGER TIRE
TREAD	32.6%
BASE	1.7%
SIDEWALL	21.9%
BEAD APEX	5.0%
BEAD INSULATION	1.2%
FABRIC INSULATION	11.8%
INSULATION OF STEEL CORD	9.5%
INNERLINER	12.4%
UNDERCUSHION	3.9%
	100.0%

5. Steel Tire Cord Analysis

The tire industry uses ASTM 1070 and above tire cord quality wire rod in the manufacture of new tires. There are approximately 2.5 pounds of steel belts and bead wire in a passenger car tire.