Goodyear continued his research for the means to make a better from of
rubber without the stickiness. He discovered that rubber was charred and
not melted by boiler sulfur. The famous vulcanizing process was
discovered and was later patented in 1844. Vulcanization was to
revolutionize the rubber industry. Sadly, Goodyear was not much of a
businessman and was unable to profit financially from his discovery. He
died a poor man on July 1, 1860 and six of his twelve children also
eventually died from diseases brought on by the Goodyear family's
persistent poverty. Charles Goodyear never saw a penny of the earnings
from Goodyear Tire & Rubber Co. since the company was formed nearly 40
years after his death .
key tire production statistics for 1998-1999 are given in the following
order to manufacture a tire the major raw materials required are: fabric
(steel, polyester, nylon, or combinations of these), rubber (synthetic
and natural types: hundreds of different types of polymers), reinforcing
chemicals (carbon black, silica, resins), anti-degradants (ozonants,
paraffin waxes), adhesion promoters (cobalt salts, brass on wire, resins
on fabric), curatives (cure accelerators, activators, sulfur), and
processing oils (oils, tackifiers, softners).
Processing & Production
tire making process (see schematic below) starts by mixing different
varieties of rubber with process oils, carbon black, pigments,
antioxidants, accelerators and other additives, each of which
contributes certain properties to the compound .
Figure 1: Schematic
of the Tire Production Process - click on photo for larger
ingredients are mixed in giant blenders (called banbury mixers) under
tremendous heat and pressure. The ingredients are blended together into
a hot, black gummy compound that will be milled. The cooled rubber takes
several forms. Most often it is processed into carefully identified
slabs that will be transported to breakdown mills. These mills feed the
rubber between massive pairs of rollers, repeatedly feeding, mixing and
blending to prepare the different compounds for the feed mills, where
they are slit into strips and carried by conveyor belts to become
sidewalls, treads or other parts of the tire.
another kind of rubber coats the fabric that will be used to make up the
tire's body. The fabrics come in huge rolls, and they are as specialized
and critical as the rubber blends. Many kinds of fabrics are used: (i.e.
polyester or nylon). Most of today’s passenger tires have polyester cord
Another component called a bead, shaped like a hoop. It is made of
high-tensile steel wire, which will fit against the vehicle's wheel rim.
The strands are aligned into a ribbon coated with rubber for adhesion,
then wound into loops that are then wrapped together to secure them
until they are assembled with the rest of the tire.
Radial tires are built on one or two tire machines. The tire starts with
a double layer of synthetic gum rubber called an inner liner that will
seal in air and make the tire tubeless. Next come two layers of ply
fabric, the cords. Two strips called apexes stiffen the area just above
the bead. Next, a pair of chafer strips is added, so called because they
resist chafing from the wheel rim when mounted on a car. The tire
building machine pre-shapes radial tires into a form very close to their
final dimension to make sure the many components are in proper position
before the tire goes into the mold.