Analysis of the ISO 6336 face load factor and its application to helical gears

The ISO 6336 Standard provides widely accepted analytical methods for calculating load distribution factors in helical gears, particularly the face load factor. However, these methods rely on simplifications that may not accurately capture real-world operating conditions, potentially leading to non-conservative results. This study critically assesses the ISO 6336 Standard approach by comparing its predictions to those obtained from an advanced finite element model (FEM) of a helical gear transmission, which incorporates a complete gear-shaft-support system. The numerical results reveal that the methods in ISO 6336 Standard systematically overestimate the face load factor in most cases, though its predictions remain close to FEM calculations for certain configurations. Additionally, the study highlights the influence of helix angle direction and power input/output configuration on load distribution, factors not explicitly considered in the standard. The findings suggest potential refinements to the ISO 6336 Standard to improve its accuracy in engineering applications.