A tire change mishap in the pit of a Formula 1 team is unlikely because it is a meticulous and calibrated operation that takes less than 3 seconds, and for this, all the elements in play are highly sophisticated: mechanical and human.
Despite all the trials, a team makes about 50 simulations of the operation During race weekend, Mercedes was blocked from changing a tire on Valtteri Bottas’ car in Monaco.
How could this happen to the best racing team in the world?
Every mechanic has two pistols on hand, the one to use and a spare beside. Therefore, there are already doubts and precautions.
Valtteri Bottas, Mercedes Formula 1, Monaco 2021
The gun that must loosen a well thought-out center nut is not just any Homecenter shelving tool. It is heavy and brutal, as it rotates at 9,000 revolutions and impacts the nut with a torque or force of 3,000 Newtons per meter (3,172 pound-feet), moved by air or nitrogen at very high pressure. This, to give you an idea, is 10 times the power of a diesel engine in a high-capacity truck. Therefore, the design of the nut flanges is no longer hexagonal, it is very complex to resist this impact and the materials are more than robust and at the same time light, similar to those of the cup that moves them.
Each nut costs more than 8 million pesos and is made of titanium, and each gun about 80 million. For that operation, only in tools, they have 640 million pesos, not counting accessories such as the cup that moves the nut.
The gun is smart. The first shot is made in the direction of loosening, it retains the nut and automatically reverses the direction for the second tightening operation. There are left and right nuts and guns because the nuts and shafts are different depending on the side of the carriage and are adjusted in the opposite direction of travel.
While that happens, one mechanic removes the wheel and another places the new one. Before, when the operation was finished, the mechanic would raise a hand to indicate that everything was finished, but they saw that time was wasted on the signals, so now Each gun has an automatic green light signal that tells the operator that the torque and adjustment were correct, and this is coordinated with a traffic light that is in view of the pilot. In passing, it informs the engineers’ computers of the details of the operation thanks to its online electronic circuits. Interestingly, in the midst of so much automation, jacks must be operated by people.
But … but … The operation requires the precision of the pilot, who must stop the car at the marks so that the wheels are completely in front of the mechanics, and this time, Bottas stopped a little earlier, centimeters, and the operator could not put the cup from the gun adjusted to the nut and when firing all that torque, the tabs were ripped off and it was round.
Total, lost race, car to the garage and the nut could not be released later even with the help of Ferrari mechanics, who a “heavy and specialized” equipment, which was nothing different from a large hammer and sawBut they couldn’t break the nut either, given its material, and the car went to the factory with the rim on, waiting to break the nut with cutting discs, special bits for titanium, torches, etc.
Mercedes officially appreciated the help of those Ferrari tools, considering that they don’t use that kind of thing in their truck to fix an F1.