Brembo The brake company celebrated 40 years in Formula 1 by giving Race car an insight into the mysteries of F1 brakes and telling us about its other motor sport activities.
Under the current Formula 1 aerodynamic regulations, the importance of the region around
the wheels of the cars has become very pronounced. Teams spend a vast amount of time and money on optimising the components used in this area and at the heart of it is the brake system.
Currently the market is dominated by two companies: Brembo of Italy and AP Racing of England, though the former owns the latter. Between them they supply every team on grid bar one with calipers (McLaren uses Akebono), and the engineering and development which goes into the brakes
is usually a closely guarded secret. But in 2015, to celebrate its 40th anniversary in F1, Brembo
decided to reveal much about the process behind its brake systems.
‘Every team has its own bespoke design, there is no off the shelf product,’ says Mauro Piccoli, Brembo’s racing director. ‘We share a lot of information to develop the products with the team, each system is bespoke, so we get involved in brake ducts as well as calipers and friction material.
Every year there is a new caliper design, front and rear. The caliper will generally remain the same for all circuits but with different discs and different ducting.’ Brembo estimates that it supplies each team with around 10 sets of calipers each season, plus up to 240 discs and 480 pads. Creating
each caliper is a predictably involved process.
‘Compared to our other calipers, those used in F1 and LMP1 use a slightly different technology with an aluminium lithium alloy material,’ Piccoli says. ‘The rules limit you to using materials which have a Young’s modulus of less than 80GPa, so we are as close as we can be to this limit. Every year we have to sign a document to say that the calipers are fully compliant with the rules. We won’t supply an illegal caliper, even if the teams ask us to.’
Tough Brake
‘The material is cast, then machined,’ Piccoli says. ‘Then the calipers are nickel plated, which offers improvements in durability and weight, as less material has to be used. In other classes of racing – NASCAR, GT, or rally – the calipers are either machined from billet or forged.’ Brembo carries out all of its own machining in house at a vast facility near Bergamo, Italy, and it machines more than just its brake calipers.
‘To machine just the body of a F1 caliper can take six hours, with many tooling changes, then you have to do the surface treatments and assembly, and sometimes the numbers are so small, perhaps just four in a batch,’ Piccoli says. ‘It really is very bespoke. We do all the machining in house, the caliper, the carbon disc, and for some teams we even machine the whole upright.
In future we are working towards a fully integrated upright and caliper, a single piece. It is very stiff like that but if there is a problem then the team has to change everything and that is quite expensive.’
The life of calipers is relatively limited. The top teams send each set back after every race for checking and servicing, while the less well funded of the teams only send them back every three or four races. It seems that an integrated upright and caliper may still be some way off.
Beyond working towards making the calipers ever stiffer and lighter, there is also the very competitive world of Formula 1 friction material. Here Brembo is up against American company Hitco, and Messier Bugatti Dowty of France.
All of them offer carbon-carbon brake discs and pads. The teams are known to swap between suppliers frequently, often based on driver preference and feel. Brembo offers a single material for brake discs and another for pads. The CER 300 material was introduced in 2013 for use in discs and the CCR 700 pad material dates back a little further. While only a single material is offered, the teams each choose to use it in a different way.
‘Every team has at least a couple of solutions for discs. In terms of cooling the teams work with us and develop many different drillings, some with over 1000 holes. Each team has its own pattern, shapes and number of holes,’ Piccoli says.
Braking Out
Brembo also operates beyond the world of Formula 1 and is in many other markets, both racing and mass production. Piccoli points out that the way friction materials are used by teams in lower level series is changing noticeably.
‘Most teams want discs and pads bedded in before delivery, so we do that on our bedding machine,’ he explains. ‘It is much better to do that than bedding in brakes on track, which is really expensive as you are basically using the car engine and all the chassis parts, plus track time, as a bedding machine.’ ‘So, sometimes we bed in other companies’ pads if that is the team’s preference.
This bedding process is becoming far more popular now; it only used to be NASCAR, which is all bedded, F3 teams and rally teams that wanted it, but now GT3 teams are asking for it more and more. I think more and more people will realise the advantage. It’s a higher up-front cost but it’s cheaper overall.’
Elsewhere in the Brembo organisation its joint venture with SGL to produce carbon ceramic braking systems is now beginning to have an impact on the racing department, which is developing new products for the future.
‘We have the new CCM-R material which is a mix of the traditional carbon ceramic process and that of carbon-carbon in racing,’ Piccoli says. ‘Normally when braking you can
see the wear, reducing the thickness of the disc, but with CCM the only way to check is to dismantle it all and weigh it.
On OEM cars they use electronics to calculate the number of braking events through a car’s life and calculate when it is time to change. This is why CCM discs should not be used for aftermarket upgrades.
If I take a disc built for a Ferrari and fit it to a Golf I have no way to check that it is okay. It’s dangerous to do that. Initially it probably works very well, but one day it will fail without warning.’ One of the main reasons that Brembo developed the CCM-R was to allow some aftermarket tuners to get the benefits of CCM but without the uncertainty over wear. Piccoli says:
‘The CCM-R uses the F1 brake material but infused with ceramic, why do that? ‘Well the F1 material is fantastic but only when it is at temperature. The ceramic infiltration means the brakes work from cold basically, so we are now offering this product. But the problem at the moment is the price, it is three times the price of carbon ceramic at the moment.
The ideal application for this is one-make classes like the Ferrari challenge. At first, the brakes cost more but overall they save money as you can race on them for up to 7000km, so that disc will last the season. DTM or GT3 type cars could also benefit from this technology’. Brembo, its subsidiary AP, and Akebono are all facing a busy time in the next 12 months, as the 2017 rules for Formula 1 could see some significant changes to the brake system.
With wider wheels and higher top speeds the design of the calipers is almost certain to be very different, but without a full set of technical regulations it’s hard for much work to be done on this now. So, in some cases, including some of the staff at Brembo, R&D people are exploring new avenues for brake systems, including a brake disc that is capable of recovering kinetic energy directly and converting it to electricity. But that’s another story …
By. Sam Collins
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