Diagnosis of Rolling Bearing by Measuring Time Interval of AE Generation

1999 ◽  
Vol 121 (3) ◽  
pp. 468-472 ◽  
Author(s):  
Takeo Yoshioka ◽  
Atsushi Korenaga ◽  
Hiroki Mano ◽  
Takashi Yamamoto
Keyword(s):  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Bearing ◽  
Rolling Contact ◽  
Time Interval ◽  
Measuring Time ◽  
Time Intervals ◽  
Measured Time ◽  
Ae Signal ◽  
Kinetics Of

We have developed a new method for measuring time intervals of Acoustic Emission (AE) generation for diagnosis of a radial rolling bearing. The method makes the AE signal itself a trigger of the oscillation of the clock pulse and measures the time interval of AE generation by integration of the clock pulses. The measurement device consists of the threshold, clock, time interval measurement and memory circuit, and was applied to rolling contact fatigue experiments. It was confirmed by the experiments that the measured time intervals of AE generation on the inner raceway or the ball agreed with the value calculated based on the kinetics of the rolling bearing. Moreover, we could identify the elements in which a fatigue crack was propagating by the method before the spalling appeared. The identified elements agreed with the failed elements.

Rolling bearing seizure and sliding effects on fatigue life

2018 ◽  
Vol 233 (2) ◽  
pp. 339-354 ◽  
Author(s):  
Guillermo E Morales-Espejel ◽  
Antonio Gabelli
Keyword(s):  
Fatigue Life ◽  
Numerical Models ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Damage Mechanism ◽  
Rolling Bearing ◽  
Rolling Contact ◽  
Frictional Stress ◽  
Lubricated Contacts ◽  
Contact Fatigue Life

The effects of kinematic sliding on rolling contact fatigue life have been discussed in many occasions, often with some disregard of the fundamental principles of tribology. In this paper, the authors’ intention is to discuss this issue with a perspective as objective as possible and performing a study on factual and known scientific knowledge, applying tribology modelling and methods. The effects of kinematic sliding of Hertzian contacts are studied from three different standpoints: (1) by analysing the combination of sliding speed and contact pressure giving rise to seizure, that is high instantaneous contact temperatures leading to film collapse, (2) by assessing the possible effects of sliding to surface traction and fatigue, (3) by discussing other possible effects of sliding in heavily loaded lubricated contacts as the concurrent damage mechanism caused by wear and rolling contact fatigue. Throughout the paper, different numerical models are presented and discussed alongside with some experimental data. This approach provides a comprehensive assessment of the various phenomena related to the kinematic sliding of rolling bearings. The different mechanisms involved and the interaction of sliding with the elastohydrodynamic lubricant film, frictional stress, wear and fatigue are discussed, and their significance to the performance of the bearing is qualified.

Location of an acoustic emission source in a radially loaded deep groove ball-bearing

1998 ◽  
Vol 212 (1) ◽  
pp. 33-45 ◽  
Author(s):  
D Nélias ◽  
T Yoshioka
Keyword(s):  
Acoustic Emission ◽  
Ball Bearing ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Bearing ◽  
Rolling Contact ◽  
Fatigue Initiation ◽  
Deep Groove ◽  
Deep Groove Ball Bearing ◽  
Subsurface Defect

This paper describes a deep groove ball-bearing analysis which has been developed to simulate acoustic emission occurring during ball-bearing operation. The computer simulation is useful to clarify experimental research on rolling contact fatigue initiation using the acoustic emission technique. Results show the ability of the method to detect and to locate a subsurface defect, due to rolling contact fatigue, before the rolling bearing failure occurs. The subsurface defect can be accurately located within the inner ring of a deep groove ball-bearing operating under radial load.

Rolling Contact Fatigue Type Analysis of Rolling Bearing by XRD and TEM

2012 ◽  
Vol 706-709 ◽  
pp. 1679-1684 ◽  
Author(s):  
H. Hidaka ◽  
Kouji Ueda ◽  
N. Mitamura
Keyword(s):  
Film Thickness ◽  
Fatigue Test ◽  
Retained Austenite ◽  
Ball Bearing ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Bearing ◽  
Microstructural Change ◽  
Rolling Contact ◽  
Lubrication Condition

In the rolling bearing, the flaking caused by rolling contact fatigue is classified into two types: surface originated flaking and subsurface originated flaking. It has been recognized that marked microstructural change can occur in subsurface originated flaking due to rolling contact fatigue. But there are few reports in surface originated flaking about microstructural change. In this study, surface originated flaking caused by rolling contact fatigue was investigated based on microstructural change. Thrust ball bearing and radial ball bearing was used for fatigue test. Simulation of dent originated flaking was carried out using the bearing with artificial dent. Another fatigue test subjected to surface originated flaking was done under shortage of oil film thickness lubrication condition. Microstructural change was measured by X-ray Diffractmetry (XRD) and Transmission Electron Microscopy (TEM) during fatigue testing. Microstructure of bearing steel used for fatigue test is consisted of martensite with small amount of retained austenite. XRD measurement reveals that the half peak width of martensite and volume fraction of retained austenite decreasing with increasing testing time, and the amount of decrease in these parameter were small in the surface originated flaking compared with subsurface originated flaking when the specimens were flaking. This suggests that surface originated flaking occurs in spite of mild microstructural change. TEM observation about the surface originated flaking shows plastic flow in the surface layer. Especially, it was confirmed that partial recrystallization occurs in the fatigue test under shortage of oil film thickness lubrication condition. But it was also confirmed that degree of recrystallization is lower in the surface originated flaking than subsurface one, and this reasonably explains XRD result. From these results, it was cleared that recrystallizaiton of martensite is differ in degree but not in kind between surface originated flaking and subsurface originated flaking.

Rolling Bearing Life Modifying Factors for Film Thickness, Surface Roughness, and Friction

1981 ◽  
Vol 103 (4) ◽  
pp. 509-516 ◽  
Author(s):  
T. E. Tallian
Keyword(s):  
Experimental Data ◽  
Surface Roughness ◽  
Fatigue Life ◽  
Film Thickness ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Bearing ◽  
Rolling Contact ◽  
Practical Calculation ◽  
Modifying Factors

This paper facilitates practical calculation of rolling contact fatigue life, allowing for material, lubrication, and surface topography effects. Modifying factors for the predicted fatigue life are given for: material matrix strength; material defect severity; EHD film thickness/surface roughness ratio Λ; surface asperity slope σθ and boundary lubricated traction coefficient μa. Readily evaluated formulas are provided for the above factors. Calculated results show predicted life versus Λ with σθ and μa as parameters. Comparison with experimental data shows that the model covers most documented test results of life versus Λ. Scanty experimental data covering σθ and traction effects on life are compatible with the model predictions.

Detrimental Effects of Debris Dents on Rolling Contact Fatigue

1999 ◽  
Vol 122 (1) ◽  
pp. 55-64 ◽  
Author(s):  
D. Ne´lias ◽  
F. Ville
Keyword(s):  
Numerical Simulations ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Surface Damage ◽  
Rolling Bearing ◽  
Initiation Site ◽  
Solid Particles ◽  
Rolling Contact ◽  
Bearing Failures ◽  
Ehl Contact

Debris dents produced by solid particles in suspension in oil or grease when they travel through an EHL contact may be at the origin of rolling bearing failures. A summary of an experimental investigation carried out to identify (i) the particle entry ratio, (ii) the mechanisms of particle fragmentation or deformation, (iii) the resulting indentation features, and (iv) the initiation site of subsequent surface damage is presented first. Afterwards, numerical simulations of a dent moving through an EHL contact are performed. A critical slide-to-roll ratio is found. Results of our numerical simulations are analyzed and discussed in relation to the concept of infinite life for rolling bearing applications. [S0742-4787(00)00901-2]

Predicting Micro-Pitting Occurrence in Wind Turbine Gearbox Roller Bearings

2010 ◽  
Author(s):  
Tedric A. Harris ◽  
Michael N. Kotzalas
Keyword(s):  
Wind Turbine ◽  
Rolling Contact Fatigue ◽  
Roller Bearing ◽  
Contact Fatigue ◽  
Rolling Bearing ◽  
Rolling Contact ◽  
Test Scheme ◽  
Wind Turbine Gearbox ◽  
Roller Bearings ◽  
Contact Fatigue Life

The standard rolling contact fatigue life calculations currently in use by the rolling bearing industry is based on the first occurrence of subsurface-initiated spalling of a raceway or roller surface. However, wind turbine gearbox roller bearings have been suffering from another damage mode, which manifests itself as micro-pitting. The micro-pitting, which is spalling on a micro scale, by itself can be tolerated in its early stages; i.e. the roller bearing will still function properly. As the damaged bearing continues to operate, the micro-pitting propagates and at the later stages, often termed peeling, the pitting becomes deep enough to reach the appearance of traditional subsurface-initiated spalling. To better understand the phenomenon micro-pitting and its causes, this study was conducted to review published literature on the topic as it relates to bearing operation. The key findings were the need for a low specific lubricant film thickness parameter, and some component of sliding velocity in the contacting surface. With this knowledge, a proposed test scheme including these variables could be created from which a method to predict the risk of micro-pitting may be determined.

Load Ratings and Fatigue Life Prediction for Ball and Roller Bearings

1970 ◽  
Vol 92 (1) ◽  
pp. 16-20 ◽  
Author(s):  
J. I. McCool
Keyword(s):  
Environmental Variables ◽  
Life Prediction ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Bearing ◽  
Rolling Contact ◽  
Load Rating ◽  
Bearing Load ◽  
Simple Generalization ◽  
Practical Life

A review of current rolling bearing load rating and life prediction practices is given, based on the ASA standard method. Experimental results show the existence of life-factors in addition to those encompassed in the ASA standard. A more general rolling contact fatigue theory is sketched but is not yet at a stage where it can be applied to practical life calculations. Therefore a simple generalization of ASA life formulas is proposed for practical use, which accounts for material and environmental variables by multiplicative factors and permits life prediction for any desired reliability using another, tabulated factor.

Rolling Contact Fatigue of Wheel and Rail

2012 ◽  
Vol 54 (5) ◽  
pp. 304-312
Author(s):  
Florian Dörner ◽  
Otto Kleiner ◽  
Christian Schindler ◽  
Peter Starke ◽  
Dietmar Eifler
Keyword(s):  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact
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