Width factor

Due to manufacturing deviations, the flank pressure is not evenly distributed over all drivers/teeth (i.e. over the circumference) and also not evenly over the width, which is taken into account by k_φ and k_b.

The width factor k_b considers the load distribution over the supporting length of the drivers/teeth due to twisting of shaft and hub by the torque. The maximum flank pressure P_max  is calculated taking into account of the width factor which is influenced by the parameters number of teeth, tooth form, connection width, clamping of the hub, hub outer diameter, shaft inner diameter, material (modulus of elasticity), backlash, type of stress, tooth deviations and wear on the flanks.