Experimental Assessment of Influence of the Ball Bearing Raceway Curvature Ratio on the Level of Vibration

Pawel Zmarzly

doi:10.26552/com.c.2020.4.103-111

Abstract

Raceway curvature ratio is a very important parameter, because its values influence the performance characteristics of rolling-element bearings, their durability and the level of generated vibrations. However, the level of generated vibrations is one of the most important operating parameters of the rolling-element bearings. Excessive vibrations generated by rolling-element bearings affect the operation of the whole mechanism. The article presents experimental studies aimed at evaluation of influence of the inner and outer raceway curvature ratios of 6304-type rolling-element bearings on generated vibrations values. The raceway curvature ratio was determined based on results of metrological measurements. For this purpose, the radii of the inner and outer raceways as well as the diameters of the balls were measured. Design and principle of operation of an innovative system for analysis of the raceway geometry of the rolling bearing rings was presented. The vibration analysis was carried out in three frequency ranges, i.e. low (50-300 Hz), medium (300-1,800 Hz) and high (1,800-10,000 Hz). Values of measured vibrations were expressed in Anderon units. The test results showed that increase in the raceway curvature ratio causes a moderate decrease in the value of the generated vibrations. The research results presented in this article will serve as a guidance to designers and manufacturers of the rolling-element bearings on how to modify the geometry of raceways and balls to obtain bearings that generate low vibration values. That is very important in car transportation.

Highlights

The rolling-element bearings are a large group of mechanical elements involved in torque transmission, while minimizing friction and the rolling resistance
Vibration values were determined for three frequency ranges, i.e. low (LB), medium (MB) and high (MB)
Max min, Analyzing the results presented in Table 1, it can be concluded that the vibration values expressed in Anderon units (And) are characterized by increased variability in comparison to the raceway curvature ratios

Summary

Introduction

The rolling-element bearings are a large group of mechanical elements involved in torque transmission, while minimizing friction and the rolling resistance. Increasing demands for improved efficiency of equipment and mechanisms, while, at the same time, reducing energy consumption, require the rolling-element bearings to have a long service life, low running noise and low frictional moment [2]. This is important in mechanisms produced using additive technologies [3,4]. The ball moves on the surface of the raceway of the rings to minimize friction and rolling resistance [5,6]. Depending on the type and application, the ball bearings can be equipped with raceways with different radii. The ratio of the radius of the inner raceway ri or outer raceway ro to the diameter of the balls Dw is called the raceway curvature ratio

Methods

Results

Conclusion