Closure to “Discussions of ‘The Measurement and Analysis of Ball Motion in High Speed Deep Groove Ball Bearings’” (1975, ASME J. Lubr. Technol., 97, pp. 348–349)

1975 ◽  
Vol 97 (3) ◽  
pp. 349-349
Author(s):  
R. J. Boness ◽  
J. J. Chapman
1976 ◽  
Vol 98 (3) ◽  
pp. 463-469 ◽  
Author(s):  
C. R. Gentle ◽  
R. J. Boness

This paper describes the development of a computer program used to analyze completely the motion of a ball in a high-speed, thrust-loaded ball bearing. Particular emphasis is paid to the role of the lubricant in governing the forces and moments acting on each ball. Expressions for these forces due to the rolling and sliding of the ball are derived in the light of the latest fluid models, and estimates are also made of the cage forces applicable in this specific situation. It is found that only when lubricant viscoelastic behavior is considered do the theoretical predictions agree with existing experimental evidence.


1975 ◽  
Vol 97 (3) ◽  
pp. 341-348 ◽  
Author(s):  
R. J. Boness ◽  
J. J. Chapman

This paper reports on a study of ball motion, including the measurement of ball rolling axis, in deep groove bearings operating at high speeds under thrust load conditions. The technique employed relies on viewing the test bearing, operating in the conventional fixed outer ring mode, through a rotating prism which eliminates optically the gross rotation of the separator. Videotape recordings of a selected ball, distinctively marked and illuminated stroboscopically, allows a complete analysis of ball bearing kinematics. Experimental results of separator speed, ball speed and rolling axis together with separator slip, ball slip and spin velocities at both the inner and outer raceway contacts are presented for a wide range of loads and shaft speeds up to 12,000 rev/min. These results are compared with the existing theory of Jones. Discrepancies between predicted and actual ball motion are due to the assumption made by Jones in neglecting bearing element slip. A further analysis of the experimental results including both gyroscopic torques and slip based on elastohydrodynamic traction values for the test lubricant explains actual ball motion more fully.


1959 ◽  
Vol 81 (1) ◽  
pp. 1-12 ◽  
Author(s):  
A. B. Jones

In modern high-speed ball bearings the pressure areas, which result from elastic deformations at the ball-race contacts, are appreciably curved and interfacial slip can occur at most points within the pressure areas. These slippages give rise to friction forces acting on the ball which are held in equilibrium by reactions from the races and the inertia effects of the motion of the ball. A method is derived for determining the motion of the ball and sliding friction in a high-speed, angular-contact ball bearing under thrust load in terms of the inertia effects on the ball and the frictional resistances resulting from interfacial slip at the contact areas. Possible elastic compliance at the interface, hysteresis, and dynamical perturbations of ball motion are neglected. The solution of eight, simultaneous equations involving double integrals for which closed-form solutions cannot be found is required. A solution for a particular case requires the services of a high-speed computer. For the case where gyroscopic effects on the ball can be neglected, certain simplifications and assumptions can be made which enable the solution of a particular problem using conventional computation means.


1978 ◽  
Vol 100 (1) ◽  
pp. 40-45 ◽  
Author(s):  
R. J. Trippett

Little experimental data for losses of high-speed Conrad type ball bearings is presently found in the open literature. Hence the accuracy of published high-speed bearing-loss predictions is not known. Accurate predictions of high-speed ball bearing loss are important, however, in evaluating high-speed rotor support systems as well as determining cooling oil requirements for this type of bearing. The losses of a Conrad type ball bearing used to support the high-speed rotors in a vehicular gas turbine were measured. The effects of bearing axial load, rotor speed, lubricant viscosity, and lubricant flow rate on the bearing power consumption were determined. Power loss calculations, made from previously published equations for this type of bearing, did not correlate well with the measured high-speed bearing losses. New power loss equations are presented to predict the losses associated with high-speed deep-groove Conrad type ball bearings under well lubricated conditions.


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