Load Distribution Measurements on Planetary Gear Systems Experimental verification of the face load factor for contact stress, K_(Hβ), and mesh load factor, K_γ, in planetary gear stages

摘要

As the power density of planetary gearboxes continuously increases, the consequential quality requirements on gearbox components lead to stringent manufacturing tolerances under rigid quality control procedures. In planetary gear systems, the face load factor for contact stress, K_(Hβ), and the mesh load factor, K_γ, are driving parameters for the size of the planetary stage. This paper focuses on the experimental verification of K_(Hβ) and K_γ by means of strain gauge measurements. The strain gauges are applied in the tooth root area of the gears and are loaded when the instrumented gear tooth engages. Today, there is no international standard available as guidance for the experimental verification of the considered K-factors. This paper introduces a procedure to determine these K-factors based on definitions of K_(Hβ) in ISO 6336 [1] and K_γ in IEC 61400-4 CD [2]. The procedure is illustrated with measurement results on a planetary stage of a Hansen multi-Megawatt wind turbine gearbox.