05/05/2011
NEWS STORY
This weekend, Pirelli's new Formula One tyres come home. The grand prix rubber is exclusively made in Izmit, Turkey: the location of Pirelli's high-tech competition tyre facility. The research and development of the tyres takes place in Milan, using mathematical modelling and chemical analysis in the laboratory as a starting point. The prototype tyres are made in Izmit, and once they have been tested and signed off for production, the definitive race tyres can be manufactured.
First of all, the bead of the tyre (the part that contacts with the rim) is made on one production line. There are around 100 separate chemical ingredients in a Formula One tyre, split among 18 major components.
Then the belt of the tyre is made on a separate production line, which defines the shape of the tyre and ensures its overall structural rigidity.
The third production line is the most crucial part of the process, as it is where the bead and the belt are moulded together to form a recognisable tyre, complete with the tread pattern. At this point the bar code - the tyre's 'passport' - is also added.
Next is the vulcanisation period during which the tyre is 'cooked'. This determines the definitive characteristics of the compound and structure.
The final step is quality control, which takes in measurements and a scan of the tyre similar to an x-ray, in order to verify the integrity and uniformity of the structure. In total, around 50,000 Formula One tyres will be made in Izmit this year, located about an hour's drive from the Istanbul Park circuit.
The 3.316 mile Istanbul Park Circuit is normally characterised by high asphalt temperatures: but this year the initial forecast is for wet weather until Saturday, when conditions are expected to clear up slightly. This means that Pirelli's intermediate and wet tyres are likely to have a proper run during a race weekend for the first time: and few places are more demanding on tyres than Istanbul Park.
There are some areas of heavy deceleration such as the first corner, where the cars change down from seventh to third gear. This can cause a lock-up of the front-left tyre due to the unusual camber and lead the flat spotting: a problem that can be reduced or eliminated with an increased grip offered by the soft tyre option.
Next up is the most technical section of the track - turns three to six - which consists of a technical sequence of curves where the driver needs to maximise speed by sticking closely to the ideal racing line.
Halfway through the lap there is the legendary turn eight, reputed as one of the most technical of the entire World Championship with three apexes and an entry speed of nearly 260kph. During this flat-out corner, the cars and tyres experience lateral acceleration of 4.6 G as well as vertical load of 950 kilograms. The higher grip of the soft tyre improves directional precision and driving safety.
After a short straight the cars reduce speed by 150 mph into a chicane with sharp but opposing corners (turns nine and 10) before another straight where the full power of the engine is unleashed once more, prioritising traction.
Turn 11 is taken flat-out at 300kp, the speed and downforce increasing the turn angle of the tyre, which also tends to lift its outside edge.
The final corner calls for precision steering with progressive acceleration in order to avoid wheelspin, which increases wear, heading back onto the main straight.
Paul Hembery: "We're seeing some wet and rainy weather at the moment, which is not what you expect from Turkey! Having said that, we came here to test with Pedro de la Rosa with the Toyota TF109 in April and we found exactly the same sort of conditions: around 15 degrees centigrade and rain, so we've got some idea of what's in store. We saw during those tests that the intermediate tyre in particular was very impressive and if conditions stay as they are this tyre could get some use tomorrow. We're hoping to have some dry running though as we have brought a new evolution of the hard tyre for the teams to test during Friday's free practice sessions, and it would be interesting to have their feedback. Whatever happens, I'm sure it's going to be a fascinating weekend."
Pirelli's Wet Tyre Range
Intermediate: These tyres have shallow three-millimetre grooves to disperse water (up to 20 litres of water per second at 300kph), but this reduces the contact patch and leads to less grip on a dry track. When the rain is heavy, drivers will switch to wet tyres at the 'crossover point'. The markings on the tyre are blue.
Wet: These tyres have deep five-millimetre grooves in them, similar to a road car tyre, and are designed to expel more than 60 litres of water per second at 300kph. A road car tyre can only displace about 10 litres of water per second, at much lower speeds. The markings on the tyre are orange