Heavy vehicles' brakes are exposed to a great deal of stress and tough climatic conditions. The total distance they cover varies from several tens of thousands of kilometres to around 250000 kilometres per year. Heavy vehicles drive up to 10 times further per year than cars and their brakes require a great deal of maintenance work. However, the technical design of brakes does not match market requirements for operating safety and lifespan. A large proportion of heavy vehicles' brakes fail to pass the Swedish Vehicle Inspection Company yearly vehicle tests. The vehicle testing methods used in inspections could be improved in order to make tests more repeatable and improve assessment of the technical condition of brakes. In order to protect legal rights, the method must be designed so that no vehicles fail the test on incorrect grounds. Operators in the road transport sector, haulage contractors, suppliers, garages, testing bodies and authorities must cooperate and adopt measures to improve the technical condition of heavy vehicles' brakes. The manufacturer of the vehicle chassis should be subject to manufacturers' obligations relating to the durability of heavy vehicles' brakes - that they should last 8 years or 1600000 km - should be considered for potential adoption within the EU. Depreciation costs as a proportion of annual costs for various vehicles differ, e.g. 14 % for round timber vehicles with 3 + 4 axles and 6 % for a tractor with 2 axles. Repair costs for round timber vehicles are approx. 12 % of annual costs compared to around 7 % for the tractor. If the purchase price for a new vehicle with better brakes were for example 10 % higher, the annual depreciation costs and consequently the freight charges would increase by 1.4 % for a round timber vehicle and by 0.6 % for a tractor. Note that a 10 % higher purchase price for a round timber vehicle combination 3+4 axles is approx. Euro 20000, and for a two-axle tractor around Euro 10000. A reduction in brake operating cost is essential. Brakes should be adjusted for all vehicles according to the standard with the working name of FDIS 20918. This will enable all vehicles to be connected and will also allow satisfactory brake operation to be maintained, with all wheels starting to brake at the same time and braking their proportion of the vehicle's weight.
Improved brakes on heavy commercial vehicles
2008
10 Seiten, 5 Bilder, 1 Tabelle, 2 Quellen
Conference paper
English
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