Load And Life Analyses Of The Spherical Roller Bearing Mounted On An Eccentric Shaft In A Mold Vibrator

Mold is the core component in a caster, and mold vibrator oscillating in the mold, which can smooth molten steel flow and improve the quality of ingot blanks. Mounted on an eccentric shaft, the spherical roller bearing is the key part in mold vibrator for producing required vibration. The bearing’s kinematics, roller load, and life prediction are important factors in the mold vibrator’s design and maintenance.In this thesis, the mold vibrator produced by SHM is taken as the research object. A dynamic model is established, with the leaf spring is simplified as an equivalent spring, the effects of vibrator gravity and load are taken into account, and the mold load is regarded as a hanging object. The model is numerically solved by use of Matlab programming, Newton method and four order Runge-Kutta method. Based on the calculating results of the spherical roller bearing’load varying with time, effects of some key parameters, such as eccentricity of the shaft, shaft rotation speed, external load, etc, on bearing’s load are analyzed,Taking the double-row spherical roller bearing mounted on the eccentric shaft as the research object, an algorithm that can accurately calculate bearing’s kinematics is developed with considering the effect of eccentric components on bearing’s rotation and roller’s speed. The numerical calculation of the model is conducted by using vector method, Matlab programming and numerical method. The roller’s rotating orbit in one period and its variation with different eccentricity are investigated. Moreover, effects of some key parameters, such as eccentricity of the shaft and shaft rotation speed, on the contact times and contact points between rollers and raceways are also analyzed.Based on Palmgren’s line contact empirical formula, a calculating model is set up by slicing crowned rollers and raceways, which can accurately compute the load experience, roller’s deformation, and raceways’displacement of the spherical roller bearing mounted on the eccentric shaft. Variations of raceways’displacement, roller’s deformation and load experience with time are numerically analyzed. Effects of some factors, such as including eccentricity of the shaft, shaft rotation speed, external load, and bearing’s endplay and preload, on raceways’displacement and roller’s load experience are also investigated.Finally, based on all the calculated results and ISO standard, the fatigue life prediction of the bearing’s components is carried out, which includes the inner/outer ring and rollers. The effects of some parameters including eccentricity of the shaft, shaft rotation speed, external load, and bearing’s preload on the spherical roller bearing’s life are analyzed.