Crown Drop Effects on the Needle Roller Bearing Life in Oscillatory

2013 ◽  
Vol 740 ◽  
pp. 295-299
Author(s):  
Xiao Yang Chen ◽  
Xue Jin Shen
Keyword(s):  
High Pressure ◽  
Pressure Distribution ◽  
Rolling Contact Fatigue ◽  
Roller Bearing ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Bearing Life ◽  
Comparison Results ◽  
Pressure Concentration ◽  
Fatigue Experiment

In this paper, the effects of chamfer dimension at the Lundbergs profile needle roller end and the grinding undercut of raceway on the pressure distribution, which are used in the oscillatory applications, are discussed. The frame of numerical method for the crown drop evaluation considered these two effects is presented, which makes it possible to profile the needle rollers axially until the longitudinal pressure distribution is neither any edge effects nor high-pressure concentration at the center part of contacts. And the crown drop designed by this method is larger than that by Lundbergs theory. The comparison results of accelerated rolling contact fatigue experiment show that the width of grinding undercut and radius of the chamfer must be considered in determining the crown drop of the needle rollers.

Near-Race Ultrasonic Inspection of Tapered Roller Bearing Components for Non-Metallic Defects

2012 ◽  
Author(s):  
Lucas Koester ◽  
Joseph A. Turner ◽  
Craig Zuhlke ◽  
Dennis Alexander ◽  
Brent Wilson ◽  
...  
Keyword(s):  
Surface Wave ◽  
Rolling Contact Fatigue ◽  
Ultrasonic Inspection ◽  
Roller Bearing ◽  
Contact Fatigue ◽  
Production Method ◽  
Bearing Steel ◽  
Rolling Contact ◽  
Premature Failure ◽  
Scanning Method

Bearing steel cleanliness is directly linked to failures caused by the interaction of subsurface defects and rolling contact fatigue (RCF). Optical analysis of as-received steel coupled with ultrasonic inspection on finished components minimizes the occurrence of defects in the near race. While useful as a preventative measure, these methods do not ensure that critical areas of components subjected to RCF are free of defects that act as stress concentrators and contribute to premature failure. This presentation provides a brief summary of the current technology and standards utilized in the industry. The deficiencies of the current methods for the particular case at hand are identified and a surface wave scanning method is introduced. The development and production of reference parts for this type of scanning are then discussed. The production method entails both traditional electro-discharge machining (EDM) and femtosecond laser machining (FLM) on finished bearing components such that the reference part microstructure resembles that of a finished part. Experimental results utilizing surface wave scanning are given for two types of assembly-ready bearing components that are then subjected to realistic service loads and mileage to the point of failure. The results of the service life simulations are then correlated with surface wave scanning results and are shown to be in good agreement. This work is anticipated to impact any field in which components are subjected to RCF.

Prediction of Equivalent Radial Loads for Tapered Roller Bearings

1996 ◽  
Vol 118 (3) ◽  
pp. 651-656
Author(s):  
Ted E. Bailey ◽  
Robert W. Frayer
Keyword(s):  
Fatigue Life ◽  
Rolling Contact Fatigue ◽  
Roller Bearing ◽  
Contact Fatigue ◽  
Subsequent Development ◽  
Rolling Contact ◽  
Tapered Roller Bearing ◽  
Applied Loading ◽  
Tapered Roller ◽  
Tapered Roller Bearings

Calculating the fatigue life of a tapered roller bearing has become a rather straightforward exercise thanks to the accumulation of rolling contact fatigue data and the subsequent development of formulation relating applied loading to bearing fatigue life. An integral part of the prediction process is to define an equivalent radial load (EQRL) by combining a bearing’s applied radial and thrust loading into a single entity. This paper reviews currently accepted formulation and offers a potentially more accurate alternative method for estimating the EQRL of a tapered roller bearing than does the current AFBMA standard.

Occurrence of High Pressure Spike in Unidirectional Start–Stop–Start Point Contacts

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
P. Sperka ◽  
J. Wang ◽  
I. Krupka ◽  
M. Hartl ◽  
M. Kaneta
Keyword(s):  
High Pressure ◽  
Film Thickness ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Elastohydrodynamic Lubrication ◽  
Rolling Contact ◽  
Point Contacts ◽  
Pressure Distributions ◽  
Machine Element ◽  
Pressure Spike

The transient film thickness and pressure distributions in point elastohydrodynamic lubrication (EHL) contacts during start–stop–start motion are discussed based on experimental and numerical analyses. When the machine element starts to move after the stopping, where the oil is entrapped between two surfaces, the pressure at the exit area increases very much. The pressure increase depends markedly on the overall film thickness before the stopping of the motion, but is hardly controlled by the acceleration after the stopping. It can be considered that this phenomenon affects the rolling contact fatigue damage.

Ball Spalling in Rolling Element Bearings: Decrease in Rolling Contact Fatigue Life Due to Inferior Microstructure and Manufacturing Processes

2021 ◽  
Author(s):  
Graham Keep ◽  
Mark Wolka ◽  
Beth Brazitis
Keyword(s):  
Fatigue Life ◽  
Rolling Contact Fatigue ◽  
Microstructural Analysis ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Rolling Element Bearing ◽  
Bench Test ◽  
Bearing Life ◽  
Rolling Element ◽  
Contact Fatigue Life

Abstract Through hardened steel ball fatigue failure is an atypical mode of failure in a rolling element bearing. A recent full-scale bench test resulted in ball spalling well below calculated bearing life. Subsequent metallurgical analysis of the spalled balls found inferior microstructure and manufacturing methods. Microstructural analysis revealed significant carbide segregation and inclusions in the steel. These can result from substandard spheroidized annealing and steel making practices. In addition, the grain flow of the balls revealed a manufacturing anomaly which produced a stress riser in the material making it more susceptible to crack initiation. The inferior manufactured balls caused at least an 80% reduction in rolling contact fatigue life of the bearing.

Application of Selected Multiaxial High-Cycle Fatigue Criteria to Rolling Contact Problems

2013 ◽  
Vol 542 ◽  
pp. 157-170 ◽  
Author(s):  
Paweł Romanowicz
Keyword(s):  
High Cycle Fatigue ◽  
Rolling Contact Fatigue ◽  
Roller Bearing ◽  
Three Dimensional ◽  
Contact Fatigue ◽  
Contact Problems ◽  
Rolling Contact ◽  
Cycle Fatigue ◽  
Contact Conditions ◽  
Tractive Rolling

The risk of fatigue failure of elements working in rolling contact conditions (such as railway wheels, rolling bearings, etc.) is a significant issue with respect to safety and economy. In this case the complex and non-proportional stress state with pulsating three dimensional compression occurs. Therefore, the analysis of fatigue life of structures working in rolling contact conditions can be performed using recently proposed multiaxial high-cycle fatigue criteria. However, there is no hypothesis that could be universally accepted for calculations of fatigue strength. Furthermore, not all criteria proposed in literature for rolling contact fatigue (RCF) analysis can predict it. In the paper, the most popular criteria based on different theories are investigated in the application to RCF problem. Moreover, modification of the popular Dang Van hypothesis is proposed. The problem of free and tractive rolling contact fatigue is analysed on the example of a cylindrical crane wheel and spherical thrust roller bearing.

Relationship between Life, Load and Rotation Speed of UHMWPE Bearing under Dry Rolling Contact Fatigue

2013 ◽  
Vol 683 ◽  
pp. 77-81 ◽  
Author(s):  
Shintaro Hazeyama ◽  
Shunsuke Oyama ◽  
Katsuyuki Kida ◽  
Takashi Honda ◽  
Koshiro Mizobe ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Rotation Speed ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Fatigue Tests ◽  
Rolling Contact ◽  
Wear Loss ◽  
Bearing Life ◽  
Ultra High Molecular Weight

The polymer bearings have been widely used in recent years. In this study, ultra-high-molecular-weight-polyethylene (UHMWPE) is investigated. In order to investigate the relation between the lives, loads and rotation speeds, rolling contact fatigue tests were conducted. It was found that rotation speed related to the bearing life and wear loss.

scholarly journals Effect of neighboring-microstructure on the rolling contact fatigue around non-metallic inclusion

2018 ◽  
Vol 165 ◽  
pp. 04015
Author(s):  
Izumi Shimoji ◽  
Masahide Natori ◽  
Hideyuki Hidaka ◽  
Yuji Miyamoto
Keyword(s):  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Bearing Failure ◽  
Metallic Inclusion ◽  
Steel Making ◽  
Bearing Life ◽  
Improvement Method ◽  
Life Improvement ◽  
Lubrication Condition

It is well known that the flaking of a raceway causes the bearing failure, and the flaking mechanism depends on the lubrication condition. In the case of ideal lubrication condition with sufficient oil film thickness, the flaking originates from a non-metallic inclusion at the subsurface. It occurs through the formation of butterfly structure due to stress concentration around the inclusion. Therefore, the countermeasure of this type of flaking is to make cleaner steel by the reduction of inclusions. However, further reduction of inclusion imposes an extra challenge for the current steel making process. Therefore, in this paper, the effect of neighbouring microstructure on the butterfly structure is evaluated to propose a new life improvement method for rolling contact fatigue. It was suggested that it’s important to eliminate strain localization near inclusion for improving bearing life.

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