CONTENTS
3
Introduction
4
The miracle material – from household items to Voyager
What exactly is rubber?
Fascinating facts about the most versatile material in the world.
6
Once upon a time
On the discovery of the Indians’ secret and how chance determined the future of rubber.
8
Manufacturing rubber
Does rubber come from tropical rubber trees or from oil?
10
Rubber takes form
It all depends on the recipe and ingredients. Learn all about how to bake rubber.
12
Why is rubber black?
Rubber comes in just about any color, but black is the strongest variety.
14
Rubber & the environment
An industry under scrutiny. On how rubber protects people and the world around us.
16
The material of tomorrow
Be inspired by how today’s research gives rise to tomorrow’s solutions.
18
A world of rubber
Join us on a journey through the fascinating world of rubber and Trelleborg.
– Sealing........................................................... 20
– Damping......................................................... 22
– Protecting....................................................... 24
300 km per hour
– and hundreds of interacting components
A modern F1 engine generates maximum power at 20,000 rpm, compared with a standard
engine whose top performance is at 4,500 rpm. Strains in the form of vibrations, heat and
G-forces are enormous and margins are minimal. The slightest error can result in a disaster.
Many of the vital components in a Formula 1 car are made of rubber or other polymer-based
materials. Not just the tires, where the choice of rubber affects everything from road holding
at 300 km per hour to wear and tear and fuel consumption, but also hundreds of other rubber
components that seal, damp and protect the extreme design.
In this brochure, you will learn everything you need to know about the family of unique materials
that we refer to in everyday language as rubber. A material that plays an important role when
mankind faces new challenges in space, in the depths of the ocean or on the earth’s surface...
With the enormous energy released at 300 km per hour,
the many rubber seals in the oil and water flows are
an indispensable part of the engine’s performance.
3
The
miracle material
– from household items to Voyager
You encounter this miracle material everywhere and every day without
even realizing it – in the car, your toothbrush, mobile phone, computer,
in chewing gum, in hospitals and in aircraft. When combined with other
materials, rubber has an almost infinite number of uses.
*
Polymerize:
Chemically join
together several
molecules of the
same type to form
a larger unit.
Elastomer:
A highly elastic
polymer material.
Rubber is one of the most hardy and
versatile materials in existence. The oldest
traces of rubber were found in a fossil
estimated to be 55-60 million years old,
discovered in 1924 in lignite deposits in
Germany. Amazingly, after being treated,
the rubber still had its elastic properties!
Rubber – an elastic concept
But what actually is the material that we
refer to in everyday language as rubber?
The short answer is that rubber is our most
elastic material, with unique properties
to seal, damp and protect in a variety of
different contexts. However, the concept
of rubber is far from uniform. There are
many different types of rubber and closely
related materials, which can be given widely
differing properties through the addition of
various chemicals.
From ice to fire
Chemical additives and combinations with
other materials such as metal, textiles and
plastics determine the final characteristics
of the end product. It might be a hose that
must be resistant to corrosive chemicals,
or a seal in an aircraft that must withstand
extreme differences in temperature.
Or why not a sound-absorbing material
that silences the humming of a hard disk?
Whatever our needs, you can count on
human beings constantly finding new
applications for this remarkable material.
WHAT IS A POLYMER?
The word polymer is derived from the Greek “poly”,
meaning “many” and “mer” meaning “part”. Polymers
are produced by polymerizing* many small molecules
– monomers – into long polymer chains. Plastic is a
polymeric material, as is rubber, fibers and binding
agents used in paint and adhesives.
Rubber is an elastic material which resumes its original
shape following deformation. When we talk about
rubber in this sense, we are referring to what physics
calls elastomers* – rubber and thermo elastomers.
4
POLYMERIZATION
Monomers
Polymer
POLYMERS
ELASTOMERS
Rubber
Thermoelastomers
PLASTICS
Hard plastics
Thermoplastics
Chewing gum is a
tasty elastomer, whose
ingredients include rubber
base, sweetener, glucose
syrup and flavorings.
Everything except the
patented rubber base is
water soluble and official
– but the unique rubber
mix recipe is a tightly
kept trade secret!
5
Once upon a time...
The history of rubber is lined with chance discoveries and a series of innovative
inventors, who have laid the foundations for modern-day rubber products in
everything from hi-tech spacesuits to designer sports shoes.
Rubber is an ancient natural material. When
Columbus and the other Europeans first came to
South America, they discovered that the Indians
were using the sap from the rubber tree (Hevea
Brasiliensis) to impregnate fabrics.
6
“Cahu-chu” means “crying tree” in Native Indian
language, and “kautschuk” soon became a concept
for an entirely new industry. However, it took a long
time before we came to realize the true potential of
this new material.
The problem was, namely, that untreated
natural rubber is sensitive to both high
and low temperatures. If it is too cold, the
rubber cracks. If it is too hot, the rubber
becomes sticky. Oddly enough, it was a
mere coincidence that would transform
rubber into a pioneering material from
which products could be made.
Goodyear and a stroke of luck!
It was Charles Nelson B Goodyear who,
in 1839, accidentally discovered that the
properties of rubber could be improved by
adding sulfur. This discovery was made
when Goodyear forgot a piece of rubber on
a hot oven covered in sulfur powder. When
he inspected the rubber afterwards, it had
changed character and now reformed into
its original shape after being stretched
– it had become elastic!
The method of heating rubber together with
sulfur came to be called vulcanization*,
after Vulcan – the God of Fire and Iron.
Thanks to this unique discovery, rubber
products now have an almost infinite
number of uses.
Mackintoshes and pneumatic tires
One of the first major rubber products was
the raincoat, first manufactured by Charles
Macintosh as early as 1823. By making a
rubber solution from rubber and petroleum,
which he then ironed out onto one side of
a piece of cloth, he created a waterproof
fabric that could be used for making
raincoats.
Another breakthrough in the history of
rubber technology came in 1888 when
Dunlop invented the pneumatic* tire, using
the gas-proofing properties of rubber to fill
a rubber ring with air. The modern tire was
born, together with everything that it has
entailed for motoring and the development
of modern society.
*
Vulcanization:
In the vulcanization
process, rubber is
treated with heat
and normally sulfur.
The sulfur atoms
form cross-links
(bridges) between
the rubber molecules, making the
rubber elastic.
Pneumatic:
Filled with air.
Elastic:
Able to return
to its original
shape after being
stretched.
Plastic:
Moldable.
THE
VULCANIZATION PROCESS
Before rubber has been vulcanized, it is not sufficiently elastic*
and strong for practical use. It also becomes sticky at warm
temperatures and hard and brittle at cold temperatures. The
reason for this is that the rubber molecules form long chains.
These are tangled in a ball, which unravels when the rubber is
stretched. In unvulcanized rubber, the chains glide past each
other and do not resume their original shape when the tension
is released. The consequence of this is that the stretch remains,
like a piece of chewing gum that has been stretched.
Vulcanization* takes place by mixing vulcanization agents,
normally sulfur, with the rubber to form sulfur bridges between
the molecular chains when the rubber mix is exposed to high
pressure and heat. These cross-links bind together the molecular
chains and prevent them from gliding past each other. However,
they still retain their elasticity. In other words, vulcanization
makes the rubber elastic* instead of plastic*. It also makes
the rubber more resistant.
Vulcanization takes place at 140-200°C in a process steered
by time, temperature and pressure. The main methods of
vulcanization are mold vulcanization (in hot molds), continuous
vulcanization (on hot rollers), in hot salt baths or in microwave
ovens), and open curing (in steam-heated vulcanization ovens,
known as autoclaves).
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Manufacturing rubber
Where does the rubber itself actually come from? Nearly
half of the rubber produced is based on natural rubber
extracted from the rubber tree, while the remainder comprises
synthetic rubber produced from oil. However, there are
many similarities in the actual production process...
Natural rubber
Natural rubber is one of the most elastic
types of rubber and is unbeatable in terms
of resistance to wear and fatigue. When an
aircraft weighing 150 tons comes in to land
at several hundred kilometers per hour, it
is the natural rubber in the tires that must
withstand the enormous stress and friction.
Other applications for natural rubber include
the production of rubber gloves for medical
use, large vehicle tires, condoms, conveyor
belts and vibration dampers.
The raw material comes from the rubber
tree (Hevea Brasiliensis), which is tapped
every second day for its sap, known as latex*,
by making slanting cuts in the bark of the
tree. The yield is approximately 10-30 grams
of rubber each time the tree is tapped.
Rubber trees live for about 35 years. The
latex is collected and transported to a
natural-rubber processing plant, where acid
is added to the latex to precipitate out the
rubber, which then hardens (coagulates).
After being washed and dried, the rubber
is cured in special smoke-houses to
protect it against mold. After the rubber has
been classified – the purer it is, the higher
the grade – it is ready for delivery in bales
to rubber companies worldwide.
Hevea Brasiliensis – the rubber tree
The rubber tree grows in the tropical zone that extends along the equator. To secure supplies
of rubber, Englishman Henry Wickham smuggled Hevea Brasiliensis seeds from Brazil in 1876,
thereby enabling plantations to be established in Southeast Asia, from where more than 90 percent
of natural rubber originates today. The largest producers are Thailand, Indonesia and Malaysia, which
together account for 80 percent of world production. There are also plantations in South America
and Africa.
DIFFERENT TYPES OF RUBBER
There are more than 20 different types of synthetic rubber, all of which
have specific characteristics, such as fire resistance, gas impermeability
or resistance to oil and weather. The prices of the various types of
rubber may vary from 1 euro to several hundred euros per kg.
Here are some of the most common types:
Styrene rubber – the most common type of synthetic rubber
Isoprene rubber – almost like natural rubber
Butadiene rubber – the hardest-wearing and most elastic synthetic rubber
Ethylene-propylene diene monomer (EPDM) – a type of rubber with
high resistance to the effects of weather and chemicals
Butyl rubber – for high gas impermeability
Chloroprene rubber – resistant to oil and weather
Nitrile rubber – for containing oil
Silicone rubber – withstands a wide temperature range
Synthetic rubber
The need for rubber increased dramatically
as its advantages were realized and as
motoring grew. However, it was not until
World War II that oil-based synthetic rubber
grades that could match the properties of
natural rubber were developed on a large
scale. The reason was the need to develop
an alternative to natural rubber, since access
to the plantations in Southeast Asia was
blocked during the war.
Today, the production of industrial and
consumer products is mainly based on
synthetic rubber. The fact is that, of the
approximately 21 million tons of rubber
produced annually, some 12 million tons
are synthetic rubber.
The raw material for the production of
synthetic rubber is oil, from which styrene
or butadiene is extracted. When combined,
these two substances form the most common
type of synthetic rubber, known as SBR
(Styrene Butadiene Rubber). Synthetic latex
is made by polymerizing* these substances.
As in the case of natural rubber, additives
are then used to coagulate the rubber. The
rubber is then washed, dried, weighed and
compacted into bales for delivery to the
rubber plant.
Latex:
The milk-like fluid
that is present in
certain plants, such
as the rubber tree,
dandelions and ficus
plants. The fluid is
an emulsion mainly
consisting of water
but also containing
numerous small
rubber particles.
Polymerization:
The process of
chemically combining
several molecules
of the same type to
form a new compound.
RUBBER PRODUCTION
1. Rubber sap (latex) is tapped.
2. The latex is transported to the raw rubber plant.
3. Acid is added to the latex, which coagulates.
4. The rubber is washed, dried and smoked.
5. The rubber is pressed into bales.
6. The rubber is delivered to rubber-production plants.
1. Raw materials are collected from oil refineries.
2. Raw materials are mixed in large vats.
3. Synthetic latex is formed.
4. Acid is added, causing the synthetic latex
to coagulate.
5. The rubber is washed and dried.
6. The rubber is weighed and pressed into bales.
7. The rubber is delivered to rubber-production plants.
2
5
1
3
Natural rubber
6
4
4
1
3
2
5
6
7
Synthetic rubber
Rubber takes form
When natural or synthetic rubber arrives at the production facilities, it
is still only a raw material. Now it is time to customize its properties
Accelerators/
retarders:
Accelerators and
retarders are used
to regulate the
speed of the curing
process.
Mold curing:
Mold curing
includes three
different methods:
– injection molding
– transfer molding
– compression
molding.
Flash:
Flash is the
surplus rubber
residue formed
when the mold is
overfilled.
according to the problems that are to be solved. The research work of
chemists and engineers produces combinations and mixes that create
products that may be stronger than steel or smoother than silk.
Mixing of raw materials
How the products are formed
The fist phase of production could be
likened to a bakery, except that sulfur is
used instead of yeast and carbon black
instead of flour. Carbon black is a filler that
also blackens rubber and gives it strength.
The actual polymer usually comprises
only about 40-50% of the total volume.
The remainder consists of other ingredients
– typically 8 -15 of them – that are carefully
weighed in accordance with a particular
recipe and kneaded together into a dough
of even consistency. In a controlled environment, the mix is given the desired characteristics prior to being stored until it is
time to model it into its final form.
Just as the mixing process was likened to
kneading dough, so can the process for
forming the products be likened to baking
bread. Certain products are rolled out, while
others are poured into some kind of mold –
sometimes in several different layers – and
yet others are extruded into the desired
shape, using various tools, prior to being
“baked.” The molds and tools are designed
in CAD design programs and are usually
made from hardened steel, which has a
shiny surface that makes the rubber product
easier to remove after curing.
INGREDIENTS IN THE MIX
1 Rubber – natural or synthetic
(the latter is more common)
2 Fillers – active fillers that strengthen the rubber,
and inactive fillers that make the rubber go further
3 Softeners – oil and/or paraffin to facilitate the mixing
process and influence the rubber’s hardness
4 Curing (Vulcanizing) agents – (mostly sulfur) that bind
the molecules together and make the rubber elastic
5 Other additives, such as accelerators/retarders*,
that regulate the progress of the curing process.
There may also be antidegradants that protect the
cured rubber from cracking, desiccation and other
changes when it ages or is exposed to weather,
bacteria, etc.
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Mold curing
Mold curing* is the oldest and most
common method. The product is molded
and cured under pressure and heat in a
molding tool. The rubber mix is poured or
injected into the cavity of the forming tool.
Extrusion
Hoses, strips and profiles are extruded
in considerable lengths. The rubber mix
is squeezed at high pressure through a
forming die. Curing is often accomplished
continuously by passing the product through
a microwave oven or a warm salt bath.
Calendering
Calendering is the name of the process
whereby rubber is rolled out to form a film,
foil or sheet (depending on the thickness),
which may then be applied as a coating to a
reinforcing material such as fabric or steel.
Among other applications, the calendered
semi-finished products are used as structural
elements in tires, hoses, rubber boots
and mats.
Coating
Coating is used to make textiles
impervious by coating the fabric with
rubber that has been dissolved in a
solvent. After the solvent has evaporated,
a rubber film has formed on the fabric,
which is then vulcanized or used as a
semi-finished product in compressionmolded products.
After-treatment
The rubber has now been chemically
processed using various additives and
has acquired its basic form. Next, the
products are processed further with various
cutting, stamping and scraping tools
to remove the waste rubber (“flash*”).
Sometimes, the surface of the product must
be treated in order to reduce friction.
RUBBER
MATERIALS = TRUE
One of the features that make rubber so unique is that it can be
attached to many other materials, including everything from metals
of various types to plastics, glass fibers, textiles and other types of
rubber. The adhesion capacity depends on the type of rubber, the
substance to which the rubber is to be attached and the type of
adhesive used.
Rubber/metal bonds
In the paper production process, rolls are used to press the water
out of the pulp. The rolls are made of metals to give them a stable
and rigid structure, but they are coated with rubber to give the
correct degree of support and friction to the paper as it passes over
the surface of the roll. The rubber/metal combination is often used
to create a rigid structure combined with the rubber’s damping or
insulating function. The most suitable metals for combining with
rubber are steel and aluminum.
Rubber/textile bonds
Many rubber products incorporate various types of textiles. These
may consist of polyester, aramids, nylon, glass fibers or natural
materials such as cotton. The textile fibers provide reinforcement
to stabilize and strengthen the material – in the production of tires
and hoses, for example, or protective clothing, for which a largemesh fabric is coated with rubber to create a gas-proof or
chemical-resistant surface.
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Why is rubber black?
It is not by chance that we associate rubber with the color black.
The pigment comes from carbon black, which is an important and
active filler in rubber. And it really is black – less than 1% of carbon
black in a mix is sufficient to blacken the rubber.
Carbon black
Carbon black is a fine carbon powder that
is extracted from oil and is used in a number of
applications to impart a color
or enhance various characteristics.
A carbon-black product that we encounter
on a daily basis in newspapers, printers and
photocopiers is printing ink. The reason for
12
adding carbon black to rubber is that it both
strengthens the material and improves its friction
and wear properties, both of which are important
in car tires, for example. The powder can also
be used to manufacture rubber that conducts
electricity – for use in antennas and traffic lights,
for example.
DID YOU KNOW THAT...
...there is a type of rubber that smothers flames
by releasing a gas that consumes the oxygen
in the air?
...the eraser was invented in 1770 by
a chemist who noticed that caoutchouc
removed marks made by a lead pencil?
It was this discovery that gave the substance
its English name: rubber.
A rubber rainbow
Although carbon black is the most common
filler, other fillers can also be used in rubber
mixes, making it possible to manufacture
products in all the colors of the rainbow.
Silicon dioxide is often used as a substitute
for carbon black, and although the resulting
rubber is not as hard-wearing, it is fully
adequate for its purpose.
For hygienic and esthetic reasons, white
rubber is often used in the food industry for
products ranging from milk hoses in dairies
to the molds used in chocolate plants.
Floors and mats are ideal rubber
products. They are ergonomically healthy to
stand and walk on, sound-damping and
hard-wearing, and can be produced in any
desired color, so that if the architect of a
building has visualized a pale pink rubber
floor to match the fittings and furnishings,
this presents no problems...
We recognize yellow or orange rubber
from protective clothing, which not only
protects rescue personnel against toxic
chemicals but is also easy to see in
conditions of poor visibility. These colors
are also used for temporary road markings,
for which the rubber is combined with
the plastic polymer polyurethane and
glass beads to reflect the light from car
headlights.
13
DID YOU KNOW THAT...
...when the UK’s first submarine was salvaged
after 69 years on the ocean floor,
the rubber seals were still in
excellent condition.
...there are some types of rubber
that can be used in temperatures
from -80°C to +400°C.
Rubber &
the environment
Nearly all industrial manufacturing entails strains on the environment
and on our natural resources. The rubber industry is no exception.
But the fact that the industry has traditionally been viewed as “dirty”
and has long been subject to public scrutiny has led to substantial
progress being made, both in terms of the external and internal
environment and in the raw materials used.
Although the actual production can entail a
strain on the environment, rubber helps to
improve environmental and safety aspects
in different contexts on a daily basis. The
material’s favorable damping properties, for
example, help us eliminate vibrations and
noise, which are a growing environmental
problem.
Thanks to the unique sealing properties,
we can seal windows and doors using rubber
strips, enabling energy savings in terms of
heating/air conditioning that are far greater
than the energy utilized to manufacture the
products.
14
Large rubber sheets under our garbage
dumps protect the countryside from toxic
substances that might leak, and intelligent
hose systems contain petrol fumes when
we fill up our cars.
A more natural synthetic rubber
In various parts of the world, research
is being conducted into alternative
rubber mixes that could be used in the
future to replace carbon black with other
fillers without affecting the properties of
the rubber mix. One variant comprises
biopolymers, which can be derived from
sugar, insect shells and algae. The main
advantage of using biopolymers is that
they are more biologically degradable than
natural rubber since they are formed from
plants or microorganisms.
Old rubber, new energy
Unfortunately, not all worn out rubber is
currently recycled. Much ends up being
dumped or burned. Incineration is in fact
the best alternative for recycling rubber
waste, since maximal energy is extracted
in the form of direct heating.
Some rubber is recycled in the form
of retreaded tires. In Finland, the majority
of worn tires end up as lightweight material
in road embankments and noise barriers.
Porous water hoses made from recycled
rubber are also in tomato plantations, where
they slowly “sweat” out the water to the
thirsty tomato plants. Rubber can also be
recycled by grinding it down and then using
it as insulating material, as indoor and
outdoor carpeting and in road surfacing.
A versatile material that can be used
again, again and again!
15
The material
of tomorrow
Will cell phones always be square,
or will we be able to roll them up
in our pockets and form them as
we want? Will we be able to
produce artificial hearts using
rubber or other elastic materials?
Rubber and other
polymer materials are
already used for medical
purposes, such as
components for prostheses
and pacemakers. In the
future, these materials will
play an important role in
“spare parts” for the
human body.
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At least one thing is certain –
rubber will play an important
role in sealing, damping and
protecting the world of tomorrow.
There is an ever-increasing demand for
materials that can tolerate higher temperatures,
higher speeds and higher pressures but that
are small, lightweight and cheap to make.
These are tough challenges that require
new, intelligent products. A rubber material
developed for oil platforms can today withstand
temperatures in excess of 1,250°C for more
than two hours. Perhaps this durable material
can be of use in other contexts tomorrow.
At the micro level
Cell phones, computers, iPods – these days,
virtually all electronics have tiny microchips
that control function and memory. A chip
of a few millimeters contains billions of
transistors and a nano-sized dirt particle can
destroy all its functions. Rubber is invaluable
during the manufacturing process, which
requires a material that resists chemicals
and gases and performs equally well in
freezing temperatures as in extreme heat.
It will be interesting to see how rubber
contributes to future technologies.
with vessels to identify their weight, speed
and angle of approach. This information
automatically adjusts the fenders’ rigidity
and energy-absorption capacity. Similar
intelligence can be built into a car’s
antivibration systems using electronically
equipped rubber mounts that alter their
geometry according to the behavior of the
vehicle, with an ability to predict movements
and actively compensate for them. What will
Green solutions
the next intelligent rubber innovation look like?
Research on new energy sources and
different ways of generating electricity is
going on all over the world. How do we best
take advantage of the forces of nature –
ocean waves, tides, wind, sun? And can we
recycle energy that we generate, such as
from the deceleration of trains and other
vehicles? No matter where the energy comes
from, rubber will play an important part in
sealing, damping and protecting materials
and components at every stage of the game.
Our mobile world
Every day, we move around in cars, planes
and trains equipped with antivibration rubber
products that make our trips more comfortable
and quieter. The bridges we drive over have
rubber seals to compensate for the earth’s
movements and provide a safe crossing.
Tunnels have seals made of rubber that keep
us dry under the water. In earthquake zones,
buildings can be equipped with rubber/steel
bearings for protection. The engineers of the
world continue to work on new, innovative uses
for rubber that can save lives and prevent
disasters.
Intelligent products
Medical rubber
Thanks to its elasticity, long lifespan and
durability, synthetic rubber is often used
in medical contexts – in everything from
instruments to pacemaker components
to prosthetic legs. Researchers are now
investigating the possibilities of combining
nanotechnology and rubber to produce
products that can control artificial muscles
or signal their status, for example signaling
when it is time to replace the knee joint.
Perhaps we can use the rubber solutions
of tomorrow to not only replace parts of
the body but to also imitate their unique
functions.
DID YOU KNOW THAT...
...that JB Dunlop, a veterinary doctor, invented
the pneumatic tire when helping his son
fix his bicycle.
...that 70,000 Hevea brasiliensis seeds
were smuggled out of Brazil in 1876.
After spending some time at a plant nursery
in the UK, the seedlings were re-planted
on new plantations in Southeast Asia.
Harbors are using rubber fenders with
embedded sensors that communicate
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A world of rubber
Every day, you use a product that seals, damps or protects – regardless of
whether you are at home, traveling or at work. The milk you drink has traveled
through rubber hoses, your newspaper has been printed on rubber-coated
rollers, your shoes have rubber soles, your car has thousands of rubber parts
and the hard drive on your computer is damped with a rubber seal.
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The rubber industry generates sales of
approximately € 105 billion annually.
The world’s largest rubber companies by far
are Bridgestone of Japan, Michelin of France
and Goodyear of the US. We recognize these
names from the tire industry, which
is where about half of all rubber is used.
Remaining rubber consumption is divided
evenly between the automotive industry
and industrial and consumer products. In
the industrialized countries, we consume
about 10-15 kilograms of rubber per person
annually and more than 700,000 people
worldwide work with rubber.
Not just tires
Within the industrial rubber sector,
Hutchinson of France, Trelleborg of Sweden
and Continental of Germany are among
the largest players. One realizes that the
automotive industry is a major consumer of
rubber on hearing that a car, in addition to
its tires, contains more than 1,000 rubber
components, of which slightly more than
100 are in the engine alone. These are
primarily seals for flow systems and vibration
and sound damping systems that make
everyday life more comfortable, safer and
more environmentally friendly.
Wherever you turn
When it comes to consumer rubber products,
the list can be made endless – from sports
shoes, condoms and hoses to gloves,
baby pacifiers and balls. In fact, only our
imagination limits the products and solutions
that can be produced from or using rubber.
Common to all rubber applications is
the fact that they are used for three
principal applications – to seal, damp and
protect – and we will be looking at this
more closely on the coming pages.
Tread
Tire wall
Foundation
constructed from
several layers of
alternating-layered
weave
Foundationreinforcement
belt
Rim
THE DYNAMIC TIRE
A lot has happened since Dunlop invented
the pneumatic tire in the 19th century. Constant
punctures and deformations have been replaced by
high-performance products, specially developed for
various functions. For example, when a military aircraft
comes in to land, its tires are subjected to an
acceleration of 0 to 300 km/hour in half a second.
This represents an enormous strain in terms of friction,
temperature and vibration. Car tires are designed for
optimum grip, braking power, comfort and light rolling
resistance for reduced fuel consumption. In forestry,
robust, self-cleaning tires are needed to cope with
Bias belted agricultural
tire (a combination of
a cross-ply tire and a
radial tire).
stony, snow covered and difficult terrain. Regardless of
the type of tire in question, all have one thing in common, the flexible and durable characteristics of rubber
– and a unique ability to seal, damp and protect at the
same time!
19
Sealing
When you drive a car or travel by train through the world’s longest immersed
tunnel, the Öresund Tunnel forming part of the fixed link between Sweden
and Denmark, you seldom consider the 100-meter rubber seals joining the
enormous tunnel sections. Thanks to rubber, we are able to seal tunnels,
doors, garden ponds, building structures and thousands of other applications.
Among tropical fish
Sealed time
Whether diving for pleasure or professionally, confidence
in equipment performing as promised is essential. Each
dive should be as fantastic – or uneventful – as expected,
which places exacting demands on performance and
safety. A durable, reliable and flexible material, purposedeveloped is required for air tubes, regulators, gaskets
and, not least, diving suits. What material are we talking
about? Surely you can guess…
Advanced micromechanics are what keep today’s
watches waterproof. Secure rubber seals ensure
that dust and moisture cannot enter and destroy the
most expensive part of the watch, the mechanism.
When it comes to precision in connection with reliable
quality, rubber is in a class of its own. For example,
the tiny O-ring between the mechanism and the
crown must maintain a 100-percent seal despite
constant friction.
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Tough challenges in space
A watertight cooperation
Hard-wearing rubber products are not only to be found
on Earth. In most space programs, rubber gaskets are
used to seal and protect sensitive equipment, requiring
maximum performance and the ability to cope with major
temperature fluctuations. This includes applications in
fuel valves and cooling systems where aggressive fluids
are used to create a comfortable working climate for
researchers.
North America’s highest building, Sears Tower, soars
442 meters above the windy streets of Chicago.
Its 16,000 gleaming bronze windows are now to be
replaced, and Trelleborg’s specially molded silicon
sealing profiles will hold the glass in place and protect
it from the elements for many years to come.
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Damping
Rubber’s ability to absorb pulse forces makes it a key material in
the fight against vibrations that harm people and property. Noise
comprises vibrations that have become an increasing problem in
our everyday lives. At the same time, our demands for quiet and
noise insulation are increasing.
Comfort on the road
A tricky equation
By now, you know that there are more than 1,000 rubber
parts in a car. Many are there to ensure that the ride is
as quiet, smooth and comfortable as possible, while the
material also contributes to economy and safety. Brake
pads, for example, are equipped with “shims,” steel
plates covered with a thin layer of rubber that reduce
squealing when braking. Suspension systems also use
rubber dampers, making them smooth and quiet. Another
interesting product is an electronically controlled engine
mount with rubber components, which provides softer
suspension on ignition, becoming more rigid when the
vehicle is in motion – all to improve comfort.
People are growing increasingly sensitive to noise
and vibrations. At the same time, engines, computer
components and many other items are being produced
from lightweight materials such as aluminum. This
creates a tricky equation, since lightweight materials
transfer noise and vibrations considerably more.
To get to grips with the problem, sandwich structures
are often used that combine rubber with aluminum
plates and that are now used to damp both noise and
vibrations in, for example, hard drives and cars.
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Silent hunter
Submarines should be both silent and invisible.
However, without rubber, most submarines would be
both seen and heard. To prevent sonar reflections
detecting the craft, entire submarines are wrapped
in rubber, which absorbs the sound impulses. Inside
the craft, hundreds of rubber products are used
to damp all mechanical sounds from pumps,
engines and life-support systems.
The world’s
quietest rail system
Hong Kong is one of the world’s most densely
populated cities. Most people live in high-rise buildings
and many of these are situated right alongside the city’s
rail lines, causing noise inside the apartments. At least
that was so until lines were laid on rubber plates that
damp vibrations and noise. The result?
One of the quietest rail systems in the world.
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Protecting
Safety is a charged word. All around the world, safety awareness is
increasing. Rescue, police and defense forces are bolstering their
resources to protect us from the threat of terrorism, fire and chemical
disasters. Regardless of whether fire, corrosive substances or gases
are involved, the world’s most flexible material plays an important role.
Fire and water
Ergonomic elegance
The worst nightmare imaginable on an oil platform has a
name. It is called a jet fire and is an enormous, explosive
flame with the intensity of a blow torch that reaches
temperatures exceeding 1,300°C in seconds, creating a
burning inferno. However, intensive research has provided
results – a sprinkler system made of synthetic rubber
that can withstand corrosion, heat, fire and explosions.
A major advantage is the systems flexibility, replacing
rigid steel, titanium and fiber-glass pipes and providing
a secure water-delivery system in extreme environments
around the world.
When manufacturing mobile telephones or other
electronic equipment, workers often stand on rubber
mats that discharge static electricity that could damage
components. This is only one of the advantages,
because with nearly a centimeter of foam rubber
below the surface material, a superbly ergonomic floor
is created, making lengthy standing periods easier on
legs, backs and shoulders, while being extremely
durable and noise-absorbent. A popular flooring
material in stores and other public environments,
as well as in industry.
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Protection against
corrosive substances
The FBI knows. Police, rescue and security forces
throughout the world know. Rubber is ideal when it
comes to protecting against poisonous gases and
chemicals. Depending on their purpose, chemical
protection suits are made from different types of
rubber. Fluor rubber, for example, can be compared to
teflon, repelling chemicals, while butyl rubber is used
for maximum gas-impermeability. These can also be
combined to provide complete protection – because
after an earthquake or major accident, you never know
what chemicals or gases you might encounter.
Safety you can feel
For a sight-impaired pedestrian, coping with traffic
can be a deadly challenge. To facilitate orientation,
tactile markings are placed at pedestrian crossings,
on stairs and on train platforms. Rubber tiles with
various raised patterns and colors can be glued
directly onto existing surfaces. The advantages are
multiple – clear sound contrast, high level of color
contrast, simple installation, etc. In addition, they
are ideal as temporary markings at, for example,
major events, since they can be removed
afterwards.
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A World of rubber is published by Trelleborg AB with the goal
of advancing knowledge of and interest in the dynamic and
fascinating material known in everyday terms as rubber.
Trelleborg
Engineered Systems
Trelleborg
Automotive
Trelleborg
Sealing Solutions
Trelleborg
Wheel Systems
Engineered solutions that focus on
the sealing, protection and safety
of investments, processes and
individuals in extremely demanding
environments.
Polymer-based components
and systems used for noise and
vibration damping for passenger
cars and light and heavy trucks.
Precision seals for the
industrial, aerospace and
automotive markets.
Tires and complete wheel
systems for agricultural and
forest machinery, forklift trucks
and other materials-handling
vehicles.
Trelleborg is a global engineering company
developing world-leading solutions in advanced
polymer technology. We employ approximately
20,000 people in more than 40 countries.
Trelleborg was established in 1905, and
the head office is located in Trelleborg, Sweden.
Our four business areas focus on specific
market segments, such as light vehicles,
offshore oil/gas, agriculture, transportation
equipment, infrastructure/construction,
aerospace and general industry. Thanks to
extensive knowledge of our customers and
their industries, Trelleborg is able to provide
unrivalled expertise and comprehensive
application knowledge.
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