The approach of determination of the waviness height on the surface of gears was developed in this paper. The analysis of surface microgeometry shows that significant waviness is inherent to the large-module cylindrical gears after machining with different types of cutting tools. There are a number of factors leading to this phenomenon: the initial state of the surface layer of the work piece being processed; the accuracy of locating and fixing the blank of the gear wheel and cutting tool; the geometry of the cutting tool and the kinematics of movement of the tool and the machined gear. All these aspects were taken into account and the expression was proposed which allows one to calculate total value of waviness Wz formed on the involute surface of a cylindrical gear. This expression is composed of all the listed components in accordance with the rules for summing random variables. The analysis of the research results shows that the main influence on the waviness during high-speed gear milling is exerted by the stiffness of the technological system, speed, feed, and the coefficient of formation of the surface layer. Verification of obtained theoretical equation demonstrated satisfying coincidence with experimental data observed in cases of gear milling with cemented carbide milling cutting tool and during high-speed gear milling of cylindrical gears with modulus m = 16 mm from 40X steel.
Keywords: cemented carbide cutting tool, gear processing, milling hob, oscillations of the cutting tool., waviness height
