Pneumatic and hydraulic trailer brakes
New provisions for brake systems
The new brake provisions for agricultural and forestry vehicles, which will take effect gradually and with grace periods, are designed to increase the safety of roads throughout all of Europe. These new provisions have consequences for the technology of towing vehicles and trailers.
“Regulation (EU) No 167/2013 of the European Parliament and of the Council of 5 February 2013 on the approval and market surveillance of agricultural and forestry vehicles.”
“Commission Delegated Regulation (EU) 2015/68 of 15 October 2014 supplementing Regulation (EU) No 167/2013 of the European Parliament and of the Council with regard to vehicle braking requirements for the approval of agricultural and forestry vehicles.”
What will change?
The new developments will affect both towing vehicles and trailers by implementing new technological requirements. In general, all vehicles are equipped with three different braking systems: parking brakes, service brakes and auxiliary brakes. From now on, only dual-circuit brake systems will be built for trailer brakes, the function of which can be either pneumatic or hydraulic. In addition, an automatic load-dependent braking system (ALB) must be installed on the trailer. The new, ancillary braking system monitor is to be clearly visible from the inside of the vehicle.
The term “braking system” refers to all of the parts which are necessary to reduce the speed of a vehicle, to bring it to a stop or to keep it stationary. “Brake performance” measures the effectiveness of a braking system, and must therefore be linked to brake pedal force and brake pressure. As before, the brake performance of towing vehicles and trailers (loaded and empty) is represented by braking curves. What is different now is how brake performance is defined and measured. Concretely speaking, the required brake performance (delay) must be reached with significantly lower brake pressure on the braking system. Since the maximum possible brake pressure for pneumatic and hydraulic braking systems remains the same, the overall result is a substantial increase in deceleration. In short: At the same brake pressure, new vehicles will brake harder than older ones.
In order to achieve this greater brake performance, correspondingly powerful control elements, axles, brake drums and brake pads are required. The new generation of trailers will therefore be more robust. Vehicle installations will be significantly more complex in the future, both from a technical standpoint as well as with regards to compliance with applicable regulations.
In particular, manufacturer obligations now take on more meaning, as changes to vehicles and braking systems can have a significant impact on manufacturer warranties.
The test specifications and test devices for inspecting braking systems for vehicle compliance have also been redefined. New braking systems must comply with the strictest of requirements regarding function, performance, response times, reliability and durability, and may therefore only be evaluated with sophisticated test methods and measuring devices.
When registering vehicles or having their types approved, technical information (brake calculations, equipment details, operating manuals, etc.) will be requested. For maintenance and repair work, the focus will be on restoring vehicles to their original condition.
For trailers with pneumatic and hydraulic brakes,
|At the same brake pressure, new agricultural trailers brake significantly harder than older ones.|