# Cylindrical gear pairs

> [HTML Version](cylindrical-gear-pairs.html)

For cylindrical gear pairs a sizing button allows to select the mesh stiffness according to ISO 6336-1. Either cga or cgb can be selected. The factors CB and CR are assumed to be equal one for the calculation of mesh stiffness.

The (./images/all_img3.png)-button behind the selection for the calculation program allows to pass a face load coefficient to the gear calculation program. The face load coefficient is calculated as:

$K_{H\beta} = \max (K_{H\beta, min}; K_{H\beta, add} + \frac{w_{max}}{w_{avg}};\frac{w_{max, fma}}{w_{avg}})$

If a value for fma is defined, it is used for the calculation of the maximum line load just based on the gear stiffness keeping constant tilting angles.