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The purpose of this paper is to present a finite element analysis (FEA) which shows the comparison between a layered cylindrical hollow roller bearing and hollow roller bearing.

In this work, FEA is carried out to solve the elastic contact between a layered cylindrical hollow roller and flat contact for different hollowness percentages ranging from 10 to 80 per cent. Graphical solution is developed to determine the optimum hollowness of a cylindrical roller bearing for which induced bending stress should be within endurance limit of the material.

Different parameters such as von Mises stress, contact pressure, contact width and deformation are shown here.

The value of this research work is the calculation of contact width and other parameters using FEA for layered cylindrical hollow roller bearing.

The purpose of this paper is to develop a mathematical model to determine optimum hollowness of a layered cylindrical hollow rolling element when it contacts with a flat plate.

In this work, finite element analysis (FEA) is carried out for different hollowness percentages ranging from 10 to 90 layered cylindrical hollow rolling elements corresponding to five standard NU 22 series bearings, i.e. 2206, 2210, 2215, 2220 and 2224. An experimental investigation is carried out for the NU 2206-layered cylindrical hollow roller bearing (LCHRB) at optimum hollowness under static loading condition.

Different parameters, such as bending stress (von Mises stress at the bore of the roller), von Mises stress, contact pressure and deflection in loaded contact are presented here.

The value of this research work is the development of a generalized solution that can be used to find the exact value of optimum hollowness for the layered cylindrical hollow rolling element, which is dependent on the yield strength of the material and the geometry of the roller under static loading condition. A static load test rig is designed to observe the load carrying capacity of the LCHRB as compared to the hollow cylindrical roller bearing.

The purpose of this paper is to establish a dynamic analysis model of composite cylindrical roller bearings, investigate the effects of different working conditions on the kinematic characteristics of composite bearings and compare the differences between them and solid roller bearings.

This paper establishes a dynamic analysis model for composite cylindrical roller bearings and proves the correctness of the established model by establishing dynamic vibration experiments and contact theory for composite roller bearings. Comparative analysis was conducted on the effects of coupling changes in rotational speed, load, number of rollers and filling ratio on parameters such as bearing static stiffness, contact stress and vibration acceleration.

The composite roller can enhance the bearing’s operational stability and minimize contact stress, but that a higher filling ratio is going to increase the bearing’s stiffness. The acceleration degree of bearing vibration, the load on the outer raceway nodes and the bearing stability all decrease as inner ring speed rises.

A dynamic calculation model of composite cylindrical roller bearings is established, and the influence of multiparameter coupling changes on bearing vibration and contact is studied, which lays a foundation for the structural improvement of the bearings.

A semi‐implicit Taylor‐Galerkin/pressure‐correction algorithm of a transient finite element form is applied to analyse the flow instabilities that commonly arise during reverse‐roller coating. A mathematical model is derived to describe the solvent coating applied to the underside of the sheet, assuming that the lacquer is a Newtonian fluid and considering the flow between application roller and foil. Here, we have investigated the effects of temporal instabilities, caused by adjustment of nip‐gap width and foil‐position, extending our previous steady‐state analysis. Foil shifting is found to have a significant influence upon pressure and lift on the foil, drag on the roller, and free coating profiles. This would result in process instabilities, such as chatter and flow‐lines. In contrast, nip‐gap adjustment has no influence on the coating finish.

The purpose of this paper is to describe a method permitting the creation of a realistic model of spherical roller bearing with the aim of determining contact stress and fatigue life based on dynamic loading conditions. The paper also aims to recognize the effect of tolerance values on contact stress and fatigue life. Motion and load transmission in spherical roller bearing occurs within the assembly by elliptical curved contacting surfaces. The stress produced by the transmitted load would be very high because of least contacting area between these surfaces.

The paper describes a methodology to determine contact stress using analytically as well as finite element method for spherical roller bearing. The comparison for the both each approach for contact stress at different loading condition is carried out. Prediction of fatigue life based on dynamic loading conditions for bearing is also determined using finite element model. The effect on induced contact stress and fatigue life by varying tolerances on inner race dimensions have been found out.

The paper suggests that the maximum stress produces at the start or end of the contacting arc under static loading condition in spherical roller bearing. The analytical and finite element approach is in good agreement. The fatigue life prediction is useful for selecting loading conditions for various applications of double row spherical roller bearing. Tolerance level at inner ring raceway radius is kept high because of manufacturing constrain of complex curvature geometric shape.

The present approach does not consider dynamic loading conditions for contact stress analysis. Therefore, researchers are encouraged to analyze the effect of wear, lubrication and other tribological aspects on bearing life.

The paper includes determination of contact stress and prediction of fatigue life for spherical roller bearing using analytical as well as finite element approach. The tolerance values at inner race are identified as per manufacturing constraint based on contact stress and fatigue life.

The purpose of this study is to investigate the contact models for contact and vibration features of cylindrical roller bearings (CRBs). CRBs are important parts of rotating machinery. The contact deformation between the roller and the raceway is an essential research topic for the CRBs. The contact deformation between the roller and the raceway can greatly affect vibration characteristics and fatigue life of the CRBs. In this investigation, six different methods are adopted to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB.

In this paper, the contact deformations and the contact stiffnesses between the roller and the raceway of a CRB obtained by various well-known empirical methods (Lundberg’s, Palmgren’s, Houpert’s, Cheng’s and Hertzian methods) are directly compared with those by the finite element (FE) method. A two degree-of-freedom (2 DOF) dynamic model of the CRB is applied to investigate the effects of the contact stiffness obtained by different line contact deformation calculation methods on the vibration characteristics, such as the root mean square (RMS), the peak to peak (PTP), the crest factor and the kurtosis of the displacement, velocity and acceleration of the inner raceway.

The computational results show that different calculation methods for the contact deformations between rollers and raceways have significant effects on the vibrations of the CRB. It is found that that the differences of computational results obtained by Palmgren’s and Lundberg’s models with respect to the FE method are smaller than those by the other three methods, i.e. Houpert’s, Cheng’s and Hertzain models. The amplitude and peak frequency of the frequency response functions from Palmgren’s method are much more similar to those from the finite element method. The above results indicate that Palmgren’s method is a better calculation method for predicting the contact deformations and dynamics of the CRBs.

This work adopts six different methods to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB. Moreover, a vibration model of a CRB is used to investigate the effect of contact stiffness obtained by the above methods on the vibrations of the CRB. The works can give some guidance for the accurate analytical method for calculating the contact deformations between rollers and raceways and the vibrations of the CRB.

The purpose of this paper is to analyze the unbalanced magnetic pull (UMP) of the rotor of traction motor and the influence of the UMP on thermal characteristics of traction motor bearing.

The unbalanced magnetic pull on the rotor with different eccentricity was calculated by Fourier series expansion method. A bearing thermal analysis finite element model considering both the vibration of high-speed train caused by track irregularity and the UMP of traction motor rotor was established. The validity of the model is verified by experimental data obtained from a service high-speed train.

The results show that thermal failure of bearing subassemblies most likely occurs at contact area between the inner ring and rollers. The UMP of rotor of traction motor has a significant effect on the temperature of the inner ring and roller of the bearing. When the eccentricity is 10%, the temperature can even be increased by about 12°C. Therefore, the UMP of rotor of traction motor must be considered in thermal analysis of traction motor bearing.

In the thermal analysis of the bearing of the traction motor of high-speed train, the UMP of the rotor of the traction motor is considered for the first time

The purpose of this paper is to analyze and optimize the roller burnishing process parameters using the design of experiments and grey relational analysis (GRA).

In this experimental work, the carbide burnishing tool has been selected for the machining of AISI-1040 high carbon steel to get better product quality and satisfactory machining characteristics. The material surface condition while machining, burnishing tool speed, feed rate, depth of penetration and No. of passes have been selected as process constraints to conduct experimental trials.

The surface roughness (SR) and surface hardness were considered as output responses. The experimental outcomes optimized by multi-parametric optimization showed considerable improvement in the process. The roller speed and number of passes are the most significant parameters for surface hardness, whereas the surface condition and roller penetration depth have the most significance on SR.

The GRA method shows the 0.03376 improvement in grey relational grade between the experimental values and the predicted values.

The experimental outcomes optimized by multi-parametric optimization showed the considerable improvement in the process and will facilitate steel industries to enhance and improve productivity while burnishing high carbon steel (AISI-1040).

This research represents valid work, and the authors have no conflict of interests.

We examine collective responses to identity threats in organizations, conceptualizing these responses as identity contests in which members of opposing groups share an identity and strive to protect the social psychological rewards derived from that identity.

We present an argument for the importance of identity as a basis for motivation, suggesting that the desires to obtain and protect identity rewards underlie much behavior in organizations. We also present two case studies from which we derive further theoretical implications about identity contests as drivers of organizational change.

Our case studies show how organizational subgroups perceived identity threats arising from actual or proposed changes in policies and practices, mobilized to resist these threats, and negotiated further changes in organizational structure, policies, and practices.

Applying this analysis, social psychologists who study identity threats can see how responses to such threats are not solely individual and cognitive but sometimes collective and behavioral, leading to changes in organizations and in the surrounding culture.

Our analysis of how identity contests arise and unfold can enrich understandings of how self-definition and mental well-being are shaped by organizational life.

By focusing on collective responses to identity threats, we offer a new way of seeing how intra-organizational identity struggles are implicated in social change.

Early fault detection of bearing plays an increasingly important role in the operation of rotating machinery. Based on the properties of early fault signal of bearing, this paper aims to describe a novel hybrid early fault detection method of bearings.

In adaptive variational mode decomposition (AVMD), an adaptive strategy is proposed to select the optimal decomposition level K of variational mode decomposition. Then, a criterion based on envelope entropy is applied to select the optimal intrinsic mode functions (OIMF), which contains most useful fault information. Afterwards, local tangent space alignment (LTSA) is used to denoising of OIMF. The envelope spectrum of the OIMF is used to analyze the fault frequency, thereby detecting the fault. Experiments are conducted in a simulated signal and two experimental vibration signals of bearings to verify the effect of the new method.

The results show that the proposed method yields a good capability of detecting bearing fault at an early stage. The new method can extract more useful information and can reduce noise, which can provide better detection accuracy compared with the other two methods.

An adaptive strategy based on center frequency is proposed to select the optimal decomposition level of variational mode decomposition. Envelope entropy is used to fault feature selection. Combining the advantage of the AVMD-envelope entropy and LTSA, which suits the nature of the early fault signal. So, the proposed method has better detection accuracy, which provides a good alternative for early fault detection of bearings.