Results of Investigating the Scuffing in Spiroid Gears

Abstract

The paper is devoted to assessment of scuffing in spiroid gears. The main requirements to performing investigations on the scuffing resistance of a spiroid gearing at a physical model are formulated. The dimensionless criterion of scuffing is determined on the basis of factor analysis. This criterion characterizes the relation between factors that influence the scuffing process in a spiroid gearing. The proposed criterion accounts for two main groups of factors: the temperature at contact and carrying capacity of the oil film. Based on analysis of existing friction units applied at scuffing resistance tests, the choice of a physical model of a spiroid gearing is further substantiated. Results of investigations carried out at laboratory stands are given, the stands being constructed on the basis of the “disk - roller” scheme of the friction unit. Results of tests of the physical model are given, namely, relations between the friction factor of a spiroid gearing and the specific load for material combinations “steel - bronze” and “steel - steel” for the range of sliding speeds and temperatures. Laws of behavior of a friction couple with material combinations “steel - bronze” and “steel - steel” are revealed at the specific load up to 400 % of the nominal one, at sliding velocities up to 205 % of the nominal one within the temperature range from 40 to 100 °С.