Brembo explains benefits of Vented brake discs
When it comes to braking on heavy-goods vehicles (HGVs), is it better to use vented or solid discs? It seems like a rhetorical question, but in aftermarket, there are manufacturers that believe replacing vented discs with solid discs is an improved solution. This is not true, according to braking specialists Brembo.
Represented by Roadlink International Ltd, Brembo says the braking system slows and stops the vehicle through friction generated by the pressure of the brake pads on the discs.
The braking torque developed is independent of the disc type (solid or vented, but in both type of discs, during braking, the vehicle’s kinetic energy is converted into thermal energy due to the friction between the disc and the pads.
Weight and Speed
The braking system slows and stops the vehicle through the friction generated by the pressure of the brake pads on the discs.
The braking torque developed is independent of the disc type (solid or ventilated), but in both type of discs, during braking, the vehicle’s kinetic energy is converted into thermal energy due to the friction between the disc and the pads.
Heat dissipation
A fundamental function of the disc is therefore to dissipate the generated thermal energy as quickly as possible, so that the system is perfectly efficient for subsequent braking.
The speed at which discs dissipate heat depends largely on the type of disc (solid or vented), the type of vents (fins or pins), and the material (low- or high-carbon cast iron). All these characteristics are of fundamental importance in the heat dissipation process.
Vented or solid discs?
The operation of vented discs is very simple: the air in the ventilation channel is expelled due to the rotation of the disc and the resulting centrifugal force.
As it passes through the vented chamber (from the center of the disc to the outside), the air removes heat from the braking surfaces, cooling them. This process cannot occur in the same way with solid discs; the air can only act on the outer surfaces of the disc, and the cooling effect is significantly reduced.
Advantages
Vented discs cool 40 per cent faster than solid discs. The lower operating temperatures of the discs result in a series of benefits for the entire braking system
On such benefit is a reduction in thermal cracking, which is the main cause of disc replacement.
Another benefit is the increased life of both discs and pads, which couple to lower maintenance costs and machine downtime result in a reduced risk of braking system fade, better performance and increased active safety of the system. Using vented discs instead of solid discs also reduces the disc’s mass, resulting in reduced fuel consumption and emissions and increased lifespan of components such as bearings and tyres.
Pillar Vented Technology
The use of special ventilation systems, such as Brembo’s PVT, in its various developments, allows for further improvements in cooling times compared to standard ventilation.
This occurs because the pin arrangement creates air turbulence within the ventilation chamber, resulting in faster cooling. The pin arrangement also significantly reduces the formation of thermal cracks on the braking surface, far exceeding those achieved with a solid disc.
For all these reasons, not only is it preferable to use vented discs over solid ones, but, in heavy vehicles where the energy involved is a critical factor for the safety and longevity of the system, it is preferable to use discs with higher-performance ventilation, such as Brembo’s patented pin vented discs, which ensure more effective cooling of the braking system.