[109] Effects of early dents progression on hybrid ball bearing surface
S Berrada1,2,3, R Serra2,3 and C Chastagner1
1SKF France
2Institut National des Sciences, France
3Laboratoire de Mécanique Gabriel Lamé – EA 7494, France
Deep groove ball bearings (DGBB) are widely used in rotating equipment in many fields, among which we have the electric vehicle powerpack, which is very demanding in terms of noise and vibration.
Geometrical design, clearance, component material and lubricant properties influence the vibratory behaviour and bearing lifecycle. Also, bearing performance highly depends on contact surface quality (ring races and ball surface). In a ball bearing, contact surface quality results from several manufacturing processes (heat treatment, turning, grinding, honing and assembly) and directly affects the noise and vibration levels generated by the bearing in the application.
When operating, contact surfaces are created between the path of the balls and rings called Hertzian contacts. It is known that even compliant deep groove ball bearings will generate vibrations due to the irregularities on contact surfaces. Under high rotation speeds and load conditions, cyclic Hertzian contacts may lead to component contact fatigue (cracks, spalling, indentation, etc). Some manufacturing imperfections, even during the early stages on contact surfaces, may aggravate this issue and lead to high noise and vibrations in the application.
Also, a wide range of different components can be used for deep groove ball bearings to stick application needs. The difference of the component material and shape affect the vibration behaviour of the bearing. It is the case of ceramic and steel balls.
This paper investigates the progression of early ceramic ball dents under high rotation speeds and different load conditions and studies the vibratory behaviour of the bearing under different operating conditions and the effect of silicon nitride ball defects on the vibration behaviour of the bearing. Experimental tests were carried out to study the evolution of ceramic ball defects under high rotation speed and load conditions. At this early stage, the fault dimension is mainly in the µm range. However, the difference of bearing component surface hardness and defect size has a major impact on bearing vibration.
Geometrical design, clearance, component material and lubricant properties influence the vibratory behaviour and bearing lifecycle. Also, bearing performance highly depends on contact surface quality (ring races and ball surface). In a ball bearing, contact surface quality results from several manufacturing processes (heat treatment, turning, grinding, honing and assembly) and directly affects the noise and vibration levels generated by the bearing in the application.
When operating, contact surfaces are created between the path of the balls and rings called Hertzian contacts. It is known that even compliant deep groove ball bearings will generate vibrations due to the irregularities on contact surfaces. Under high rotation speeds and load conditions, cyclic Hertzian contacts may lead to component contact fatigue (cracks, spalling, indentation, etc). Some manufacturing imperfections, even during the early stages on contact surfaces, may aggravate this issue and lead to high noise and vibrations in the application.
Also, a wide range of different components can be used for deep groove ball bearings to stick application needs. The difference of the component material and shape affect the vibration behaviour of the bearing. It is the case of ceramic and steel balls.
This paper investigates the progression of early ceramic ball dents under high rotation speeds and different load conditions and studies the vibratory behaviour of the bearing under different operating conditions and the effect of silicon nitride ball defects on the vibration behaviour of the bearing. Experimental tests were carried out to study the evolution of ceramic ball defects under high rotation speed and load conditions. At this early stage, the fault dimension is mainly in the µm range. However, the difference of bearing component surface hardness and defect size has a major impact on bearing vibration.
