The experimental determination of the dynamic radial stiffness of an angular contact ball bearing

Abstract

To evaluate the A. B. Jones bearing stiffness predictions on an angular contact ball bearing, experimental testing on an angular contact ball bearing was conducted. Objectives of the testing were to determine the effects of thrust load, rotational speed, and radial load on the radial stiffness of the bearing, and compare the experimental data with analytical predictions from the A. B. Jones Code. A hard mounted bearing was tested, as well as a bearing in series with a soft outer race carrier. Three different types of testing were used: static pull testing, eigenvalue frequency testing, and critical speed testing. An XLTRC[TM] model of the test rig rotor was used to process collected data into useful bearing stiffness values. Bearing stiffness predictions based on the A. B. Jones bearing equations were calculated for equivalent thrust and radial loads seen in testing. Measured values ranged from 20,000 kN/m to almost 300,000 kN/m, while predicted values were in the range of 60,000 kN/m to 150,000 kN/m. Overall, predicted and measured stiffness values did not compare well for either of the two configurations tested.