Importance of wet grip for winter tyres

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Goodyear Dunlop Workshop
Importance of wet grip
for winter tyres
This year’s Goodyear Dunlop Winter Tyre Workshop had the motto “Wet Grip of Winter Tyres”.
The tyre manufacturer invited several press representatives to the ADAC Driving Safety Centre
Grevenbroich. Apart from some expert presentations the programme also included some driving
demonstrations.
E
xperts are constantly pointing out
how important appropriate tyres in
summer and winter and the condition
of the tyres, e.g. tread depth, are in order
to guarantee safe driving. Although it could
be expected that each car driver should
have become aware of this in the meantime, statistics reveal that both the type of
tyres and their condition can among others
play a crucial role in accidents. Specialized
tyre trade should continuously raise customers’ awareness in consultations that
tyres have a huge impact on safety.
Lars Hannawald gave a presentation on an
analysis of data based on real accidents
happening in winter on behalf of the traffic accident research at TU Dresden. One of
the results of the analysis was that during
the winter season from October to March
passenger cars were nearly double as often
involved in accidents on wet roads as during
the half-year summer season. According to
the expert, the share of grip-relevant situations in traffic accidents on wet roads reached
81 per cent in winter. “This high share illustrates the huge importance of wet grip of tyres in order to reduce the risk of accidents
“, said Lars Hannawald. According to results
of the study, there was additionally a higher
number of accidents on wet roads in winter
than in summer. Thus, wet grip features of
winter tyres play a crucial role. “In addition
to this, more than one in five passenger cars
causing an accident with personal injury was
only equipped with summer tyres in the six
months of winter“, explained the expert.
The following tendency was summed up by
the expert: “If people are on the road with
wrong tyres, they will more often cause an
accident.”
Compound technology
Apart from tread design compound technology has a substantial impact on the best
possible wet grip of winter tyres. “Meanwhile, components of modern winter tyre
compounds like polymers, fillers and plasticizers have become far more efficient and
can more easily be processed“, illustrated
Saburo Miyabe, tyre developer at Goodyear Dunlop. Functionalizing polymers reduce
inner friction of a tyre and thus improve
rolling resistance; silica as filler, plant-based
oils and traction resins as plasticizers are
to provide improved wet braking and wet
grip.
During the past twenty years technology has continuously developed. As performance could be increased from a Golf III
with 44 kW to a Golf VII with 90 kW, con-
sumption was decreased from about 7 litres/100 kilometres to about 5 litres/100 kilometres and tyre size rose from 175/70 R13
to 205/55 R16, the compound technology of
Goodyear UltraGrip tyres also fundamentally changed from 1994 to 2014. Workshop
participants could check in a hands-on activity that the tread compound based on
the technology in 1994 has not only been
Lars Hannawald gave a presentation on an
analysis of data based on real accidents happening in winter on behalf of the traffic accident
research at TU Dresden
The UltraGrip 9 in a braking comparison with a UG9 produced with a
20-year-old compound technology.
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further developed until 2014, but has also
caused significant performance differences
on wet roads, e.g. concerning wet braking.
They could compare the wet braking behaviour of the latest UltraGrip 9 with an UltraGrip 9 produced with an old compound in
a wet braking test. As stated by Goodyear,
a vehicle equipped with modern winter tyres was able to stop at a speed of 80 after
about 33 metres; a vehicle with tyres of a
20-year-old compound technology needed
about 41 metres for a stop.
Moreover, there are many variations
among the wet braking performance of
winter tyres concerning the different EU
Tyre Label classes. “More than 90 per cent
of all the winter tyres being on offer belong
to label classes C or E”, clarified Thomas
Salzinger at TÜV Süd. “Nevertheless, when
comparing a tyre with an average value of
class C with the wet grip of a tyre at the
lower limit of the second-most relevant
label class E, the braking distance on wet
roads showed variations of more than 20
per cent. Based on emergency braking at a
speed of 100 km/h this could be 10 metres
or even more.“ If the speed of a vehicle is
reduced from 80 to 20 km/h, there will still
remain a speed of 38 km/h for the vehicle
with E tyres.”
Higher versus lower grip
Owing to this higher impact speed of more
than 20 km/h, the risk of injuries for vehicles
occupants will be considerably higher“, added Peter Schimmelpfennig at crashtest-service.com GmbH. Crash tests carried out with
impact speed of 20 and 38 km/h revealed
that vehicles with an increased impact speed
had extremely higher damage to property“.
Many workshop participants listened to
the presentations at the ADAC Driving
Safety Centre Grevenbroich.
While a vehicle equipped with high-grip tyres
crashed into a truck only had “insignificant”
car body damage in the front part, damage
was far more serious after a crash at a speed
of 40 km/h. Safety systems like air bags did
not offer any advantages as they are often
not released when having a rear-end collision with a commercial vehicle as the deceleration value is too low. Moreover, follow-up
costs were higher after a rear-end collision
with a truck, if vehicles were equipped with
low-grip tyres. In addition to this, the safety
of further road users could be endangered.
Workshop participants could gain first-hand
experience on a skid pad how a too low tread
depth – two millimetres in the test – influenced driving behaviour on wet roads. Lars
Hannawald showed as well in his study how
important the condition of tyres – in this case
their tread depth – was in accidents: “One in
five cars involved in an accident had a tread
depth below the recommended one, one
in thirty below the legally mandatory tread
depth.” Furthermore, there is a significantly
higher risk of causing an accident because
of skidding on wed or snow-covered roads
in the half-year winter season. According to
the study, even one in six vehicles equipped with ESP caused an accident on snowy
or ice-covered roads. Thus, the efficiency of
active vehicle safety elements – apart from
ESP also ABS or a braking assistant – is highly
influenced by the type of tyres. As a consequence, specialized tyre trade or garages
should raise car drivers’ awareness that they
should not exclusively rely on assisting systems, but appropriate tyres too.
(akl)
A vehicle could start
skidding on wet roads
because of a tread
depth of only two
millimetres.
english
section
Case Study from Continental
“Tires for the Future –
We develop sustainability”
The topic “sustainability” is of high importance for the tyre manufacturer Continental. As a consequence,
several the most different experts work together in research and development, in testing and in production
in order to get the tyres for the future being even more energy-saving and environmentally friendly concerning production, use and recyclability. Because of this all the components of a tyre are continuously scrutinized and, if necessary, replaced by more environmentally friendly materials.
M
ore sustainable processes are also
to be implemented in production:
Rubber waste is reused in production in a recently developed process, which
even means that parts of worn truck tyres
could be used in retreading.
Tyres for hybrid vehicles
Special tyres for hybrid vehicles are the latest products of the tyre manufacturer.
According to company information, they
have a 30 per cent lower rolling resistance
compared to conventional tyres. Hybrid
vehicles equipped with these tyres will
have to rely less on its engine and thus the
driving distance via electric drive will get
much longer. “New vehicle concepts for emobility will open enormous development
possibilities – not only for the tyre design”,
said David O’Donnell, Head of International
Research and Development at Continental.
The Conti.eContact represents a special tyre
line for e-vehicles in the range of the tyre
manufacturer. The radius of e-vehicles is
supposed to be maximized with higher and
smaller tyre sizes 195/55 R 20, which are
characterized by a 30 per cent lower rolling
resistance compared to conventional tyres.
The further developed tyre with completely new materials is the first Continental
summer tyre the manufacturer labels with
the EU Tyre Label rating A for wet grip and
rolling resistance.
Technical highlights
The Green Chilli rubber compound is meant
to join maximum grip and minimum rolling
resistance at the highest level of safety and
handling. The tread design with new Hydro
sipes focuses on ideal water drainage and
thus the best possible wet braking performance. According to company information,
the flexible and aerodynamically improved
Aero Flex sidewalls will also reduce rolling
resistance and fuel consumption. Further-
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Continental presents its
case
study “Tires for the Futu
more, the ContiSilent technology of the
new Conti.eContact will decrease the interior noise level.
Tyres from dandelion
Moreover, Continental works together with
Fraunhofer Institute for Molecular Biology
and Applied Ecology/IME) concerning “tyres from dandelion“. This cooperation aims
at the use of natural rubber extracted from
the root of dandelion as economically usable
replacement for natural rubber from the rainforest. These plants could even grow on land,
which is not suitable for food production. As
a consequence, cultivation in Central Europe,
which means a “plantation next to the tyre
plant”, would economically and ecologically
make sense and reduce CO2 emissions due
to shorter transport distances. Monoculture
re – We develop sustain
ability”.
of rubber trees in rainforest areas could be
decreased and tyre bakers could slightly be
less dependent on fluctuations at the international natural rubber market. According to
group information, the advantage will soon
be very comprehensible, when considering
that between ten and 30 per cent of rubber
in a passenger car tyre come from the rubber
tree called “Hevea brasiliensis“.
The case study “Tires for the Future – We
develop sustainability” from Continental
can be downloaded via the following link:
http://www.continental-reifen.de/www/
download/reifen_de_de/themen/news/
download/dl_2014_08_01_green_tires_
(akl)
pdf_de.pdf The Tire Cologne Kick-Off Event
Communication as answer
to complexity
At the beginning of October, Koelnmesse launched its information campaign for the first THE
TIRE COLOGNE 2018. Responsible people together with German Federal Association of Tyre Trade
and Vulcanizing Handicraft (Bundesverband Reifenhandel und Vulkaniseur-Handwerk e.V. /BRV)
invited representative of the tyre industry to an information event at the trade fair grounds. The
future trade fair team presented the range of services of Koelnmesse and illustrated the chances
of the tyre industry at the new trade fair location.
I
t is very important for us to start an active
communication with all the representatives of the industry at an early point. This
information event was the starting point“,
Christoph Werner, Vice President at Koelnmesse, explained the event. “Owing to this
exchange, we will be able to meet the exhibitors’ requirements concerning THE TIRE
COLOGNE in a tailor-made way.” Based on
the motto “Communication as answer to
complexity!” Koelnmesse presented the
full range of its services and the plans for
THE TIRE COLOGNE based on theme islands.
In 2018, about 70,000 square metres of exhibition area in halls 6 to 9 as well as the
Congress-Centrum with 14 rooms will be
available. The halls are unsupported, flooded with light, at ground level and dispose
of a height of 11 up to 15 metres. Exhibitors
and visitors can look forward to the fifths
biggest trade fair grounds in the world located in the biggest European business area.
Koelnmesse and BRV consider themselves
well prepared with 90,000 hotel beds in
the region and the three biggest German
airports within a radius of only 150 kilometres for the relocation of the tyre industry.
Koelnmesse has indeed already several
times proven its expertise concerning the
relocation of bigger trade fairs, like leading
industry trade fairs e.g. dmexco, FIBO and
gamescom. According to responsible people at the trade fair, the events were able to
increase the number of visitors by between
50 to even more than 150 per cent and with
regard to exhibitors by between 25 and 200
per cent after the relocation to Cologne.
The team for THE TIRE COLOGNE will strategically focus on internationalization. Apart
from activities in Germany, presentations at
trade fairs and talks with multipliers in foreign countries are planned as from 2015. International advertising and public relations
activities will continuously be increased
Koelnmesse presented the range of its services and plans for THE TIRE
COLOGNE based on theme islands.
until 2018. As a consequence, Koelnmesse
will make use of its international network,
which consists of local representatives in
more than 100 countries ready for personal
contacts with exhibitors and identification
of visitor target groups.
Several services will be at the disposal
of exhibitors, visitors and press representatives in Cologne: From booking hotels with
fixed special rates, online Matchmaking
365 for dealing with inquiries and coordinating appointments to databases of novelties and images during the trade fair. About
50 representatives of the industry made
use of the invitation to Cologne. After the
presentation of the theme islands, the invited guests could be convinced of the
know-how and the services of the trade
fair company: the INTERMOT Köln, which
took place in nearly the same halls as the
THE TIRE COLOGNE will, invited to a visit after the event.
(kle)
There will be more chances in Cologne according to
Peter Hülzer, Managing Director at German Federal
Association of Tyre Trade and Vulcanizing Handicraft
(Bundesverband Reifenhandel und VulkaniseurHandwerk
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