Mathematical Modelling -- A Basis for Bushing Loading Guides

A simple mathematical thermal model is proposed as a basis for a bushing loading guide. It is demonstrated to have adequate accuracy for both steady-state and transient bushing hot-spot temperature calculations. Model constants can be derived from a set of "Overload Qualification" tests and recommendations are made for the parameters of significance to these tests. Three possible thermal failure modes are examined to establish a basis for setting a maximum permissible hot-spot temperature during overloads. Limitations on environmental factors which influence the bushing hot-spot temperature are also discussed.