Abstract
The paper presents an issue that concerns the field of freight transportation since July 2004, when the Romanian Auto Registry introduced a new reglementation regarding the method of verifying the brake systems for semitrailers. According to the new procedure, which artificially divides the semitrailers park in two parts (depending on manufacturing year - before and after 2001), estimations are made for the brake forces and braking ratio at maximum load, depending on brake forces and the brake chambers pressure measured at empty load. These estimations are not very well fundamented, and may be susceptible of interpretations. If applying these estimations, the majority of semitrailers manufactured after the year 2001 may have false poor brake efficiency, so they can be dangerous in traffic. The authors try to elucidate this matter in the paper.
Keywords: Brake forces, braking ratio, semitrailers, axle, brake chambers pressure, admissible weight