Can a single piston brake be as good as a twin or multi piston brake? This debate has raged for many years.

From a general business perspective there are straight forward arguments for a single piston brake which includes fewer parts, no need for synchronisation, lower weight and expected less cost.

From an engineering perspective arguments are focused on performance, deflection (i.e. stroke demand), equal pressure distribution on the pad (taper wear, general pad wear and rotor load distribution) and packaging in the wheel end.

Because there is not a brake which can satisfy all of the expectations expressed above without any contradiction or compromise on one or the other side, there is the need of getting a good understanding where the limitations are and where are the zones of overlap, swap over criteria and the portfolio boundaries.

These transition areas are defined by duty profile, installation locations and market acceptance criteria expressed by installation location as in front, rear and tag axles; light, medium and heavy duty applications or territorial preferences and acceptance levels.

Technology developments of increased retardation systems, hybrids, full electric - and autonomous drive vehicles will change the duty load profile significantly. A shift of these boundary conditions opens opportunities for new system centred perceptions and might allow brakes for a project where they are rejected today.

Thomas Paul, Meritor Heavy Vehicle Braking Systems UK Ltd. United Kingdom.