Fifth wheels and kingpins


D-Value = g x
0,6 x T x R / T + R - U


  • T = Weight of the towing vehicle including the vertical load on the fifth wheel;
  • R = Weight of the semitrailer;
  • U = That part of the semitrailer weight which is directly transmitted to the fifth wheel.
  • g = Gravitational acceleration; 9.81 m/s2;
  • D-Value = Theoretical load for the determination of the theoretical horizontal dynamic force between towing vehicle and steering axle trailer;


T ton  
R ton
U ton
T* ton
D-Value kN