How is rubber used in the F1 industry?
Posted on 02/12/2014 Category: Technical Features
The Formula 1 and motorsport industries are a multi-million pound global industry with leading edge technologies, so if you ask how is rubber used in the F1 industry, the answer might surprise you, with applications and compounds that are constantly evolving to complement the properties of more “exotic” materials.
From championship winning F1 competitors such as Mercedes, Ferrari, Williams, Red Bull and Mclaren through to World Endurance factory teams Audi, Toyota and Porsche, the drive for ever more performance from less fuel has meant intensive research into leading edge technologies on all sides. Chassis, tyre, suspension and aerodynamic development has been rapid over the last few years in the constant search for more performance, while the introduction of the 2014 F1 “Power Unit” has moved the goalposts a long way on from what was previously the accepted view of class leading use of energy recovery and deployment. Notwithstanding this exciting development in F1, the somewhat more open rules of the World Endurance series has further widened the scope for the application of more novel approaches to solving the same fuel efficiency versus speed challenge, with all the major manufacturers in this series taking different approaches with their solutions to the criteria governing the competition, all in pursuit of that winning performance advantage. To win at the pinnacle of motorsport, the efficiency of the car is paramount both in terms of maximising the aero performance for the best lift to drag ratio, and making the best use of the controlled amount of fuel available for the race. Gone are the days of unlimited fuel, engines and tyres, and as a result every avenue for optimising performance within mandated rules is sought, often requiring some creative thinking. This fertile seedbed has lead to huge amounts of R&D investment and delivered ground breaking solutions that have changed the face of motorsport, and yet, despite the advent of exciting new materials and technologies, its is surprising just how often our traditional “rubber” products play a vital role in enabling these technological improvements to work efficiently and reliably. Certainly, rubber materials and designs have been subject to challenges previously unheard of in terms of temperature extremes, friction requirements and controlled stiffness for example. There is often the opportunity for rubber to be combined in composite structures as the key element binding together a series of disparate materials in order to create a final assembly that outperforms the sum of its parts, and rubber has risen to all these challenges. The necessity for a fast car to also be consistent and reliable is often the reason why rubber is the key element to a winning solution. Whilst there is no magic “rubber” that can do everything, and it does require specialist knowledge of the various polymer types and their attributes to achieve the best design and thus the required performance from any given part, it is remarkable just how integral the unsung yet exciting material family that is “rubber” is to delivering the full performance of a current F1 car – quite apart from the obvious contact of the tyres with the road. The lessons learned in the white heat of high end motorsport are now finding their way into everyday road vehicle applications, so it really is the case that technology from motorsport does transfer into the real world, for everyone’s benefit.
Hover over the graphic below to see reveal how rubber is used in the F1 industry on a car…
Wheel Aero Seals
The control of air around and inside wheels, rims and upright assemblies is critical for reliable performance of the brakes and tyres. Controlling the tyre and brake temperatures, either to warm them up or cool them down can make huge differences to lap times and endurance. Shaping and ducting the air flow generated through the hub assembly uses the unique properties of rubber to form compliant seals between mating surfaces, in both static and dynamic applications. The environment can often be quite aggressive, and special grades of rubber are required to provide the necessary performance and service life.
Spark Plug Boots
The energy required to reliably create a controlled spark in the combustion chamber of a new generation F1 power unit is immense, and avoiding insulation breakdown is a priority. Specially developed high dielectric rubber grades provide the necessary electrical and thermal performance to ensure a high quality spark is consistently generated at just the right time and place by the coil pack.
Moog Valve hydraulic pipe separators
The ever more complex control systems designed to actuate the clutches, gears, differential and steering of a current F1 car require a series of small but strong high pressure hydraulic lines to feed them. Every time these complex pipes pass through a housing or bulkhead, a rubber “grommet” is required in order to protect from chafing and damage to the pipe. The geometry of these parts is often very complex due to the extreme packaging requirements demanded of all the mechanical installations in order not to compromise the aerodynamic performance of the car.
Flexible Air-Wetted components
Where parts of the car move in relation to the chassis, such as in suspension mounts and steering arm gaiters, rubber has a key role to play. Whilst a conventional road car rubber boot certainly performs its primary role of keeping dirt and grime out of sliding or rotating assemblies, these traditional boots are quite bulky items, and deform in inconvenient ways when stretched. On a current F1 car, rubber gaiters and boots which are in the airflow stream have to remain stable in shape at all times, in order not to compromise or introduce unpredictability into the flow of air around the component they work with. This does require some clever design and material selections, but is a key area where rubber is still the best material to help in the ceaseless search for performance gains.
Whether traditional rubber and metal bonded components (albeit highly specialised, individual bespoke grommets and bushes or integrally moulded inserts), rubber helps control the enemy of reliability on a modern F1 car: vibration. The damping properties of rubber have a vital role to play in protecting assemblies and sensors from damage by excess vibration, thus allowing long term optimum reliability and performance. The design for any given mount and the material it is made of will depend on the environment it has to operate in, with extremes of temperature requiring high specification synthetic rubbers, or repeated impact perhaps finding other rubber materials to be more suitable. Damaging vibration harmonics can be changed unexpectedly by things apparently unrelated such as a change of camshaft profile, or ECU mapping. Under these circumstances, anti-vibration mounts that used to be entirely satisfactory can suddenly start to fail due to the changed harmonics, requiring another round of R&D to be done in order to address the new environment.
Steering Wheel Inserts
We all know that the contact the driver has with the ground is through the rubber tyres, but often the first contact the driver has with the car is with rubber grips on the steering “wheel”. This is where design and engineering get put to one side as individual driver ergonomic preferences take over; highly personalised solutions are often required. Each driver will have a different preference for the shape and hardness of the coating they are using, in order to give them that critical feel. The rubber may also be covered with other natural or synthetic materials to provide that final, perfect feel that allows the driver to fully express his talent behind the wheel without distraction.
Powertrain system seals
The highly complex KERS / ERS energy storage systems that collect and discharge electrical energy from the MGU-K and MGU-H many times per lap on a current F1 car need to be very efficiently cooled, and rubber plays a key role in this. Keeping the respective fluids contained in the primary power storage casing requires seals of very specialised materials and designs, and often, very tight tolerances. There is also a secondary containment for safety to prevent release of potentially dangerous materials and components in the event of a crash, and this also requires seals to complete the enclosure. Of course, the power cell unit also contains more than its fair share of rubber grommets, anti-vibration mounts and cable seals. Other parts of the powertrain such as the turbo of the MGU-H and the motor generator of the MGU-K also present their own sealing problems, with some fairly extreme environments.
Radiator Duct Seals
Controlling airflow around and inside a modern F1 car is critical; too much cooling costs extra drag and loss of speed, too little costs reliability and engine performance, yet it is often a quite mundane piece of sponge or solid rubber that solves the problem of how to seal up the various small gaps between the highly sculpted bodywork and radiator systems on the car. Given the extreme aerodynamic shapes and the tight packaging of components on a modern F1 car the shapes of these “boring gaskets” can be quite interesting, and they do perform a vital service in delivering the full performance of the car.
We all know what a road car one looks like, and until a few years ago, F1 components looked quite similar, as did Boots in other racing applications requiring all wheel drive or control. However, once again the ever present drive for aerodynamic efficiency has dictated that they have become almost unrecognisable compared to their road car cousins, with the lowest possible interference with the airflow past the gearbox and driveline being continuously sought. The closer the gearbox “Boot” and the associated driveshaft bearings can sit to the centreline of the car, the better the airflow can be around the rear of the car, reducing drag and optimising the amount and predictability of the downforce generated by the car. The performance gains in this area when considering the design of a “boring” piece of rubber can be quite significant in the overall solution.
Low Friction Seals
Although rubber has quite a high coefficient of friction in its own right, there are ways to modify its characteristics to have the best of both worlds. Rubber can be specially compounded with low friction additives to reduce drag, or it can be bonded to other materials such as PTFE so that the sealing contact surface is low friction, but is surrounded and energised by rubber. It is also possible to fluorinate the surface layer of a rubber part and modify the surface molecular structure to give a much lower level of friction while retaining the original properties of the part. All these methods come into play when making that “boring” rubber part deliver a key element in enhanced performance by reducing friction, wear, or increasing the service life of components. Although the vulcanisation process for natural rubber was discovered in the 1850’s, and synthetic rubbers were first developed in the 1930’s, there are constant developments in rubber technology, and novel combinations of properties are being driven by the development of new solutions such as nano technology and graphene applications. As can be seen, whilst the investment in the F1 industry is specialised and substantial, many of the advances in research, technology and manufacturing can be applied in refined forms to the everyday cars on our roads. It is also leading to the establishment of many spin-off companies which further develop and provide subcontract solutions that started out in F1, which, as these technologies mature, are finding applications in mainstream transport and aerospace industries. The end result of this intensive focus and development is an increase in product performance, and since even in the case of F1, performance means not just speed, but economy, reliability, comfort, enjoyment and safety too, you can see how the application and evolution of many of these kinds of rubber materials and components remains relevant in the mass production of today’s modern vehicles and products.