scholarly journals Experimental investigation of ball bearing lubrication conditions by shock pulse method

2019 ◽  
Vol 36 (1−2) ◽  
Author(s):  
Ratnesh Kumar Gupta ◽  
Vikas Rastogi ◽  
R C Singh ◽  
N Tandon
Keyword(s):  
Ball Bearing ◽  
Pulse Method ◽  
Operating Conditions ◽  
Condition Based Maintenance ◽  
Ball Bearings ◽  
Shock Pulse ◽  
Optimum Conditions ◽  
Wear And Tear ◽  
Lubrication Conditions ◽  
Bearing System

Lubricant (grease) is a vital requirement of ball bearing system. Grease not only protects ball bearing from wear and tear but performs various other functions that are essential for proper functioning of ball bearings. The lubricant (grease) under different conditions attains different properties which in turn affect the performance of the ball bearings. The effect of the condition of the lubricants on the performance of the ball bearings is well documented. the work reports about the investigation of ball bearing using shock pulse method by using two different instruments (Tester T2000 Model and Shock Pulse Meter 43A) of different operating conditions of ball bearing the condition such as used the quantity of grease as different percentage (0%, 25%, 50%, 75%, 100%) and bad quality grease (burn grease) at different rpm at a fixed load (10kg) and compare the normalized shock pulse value (dB) at different operating conditions. This method uses a piezo-electric accelerometer superimposed electrically as well as mechanically to about 32 kHz of resonant frequency. The result will help in bearing related to quantity as well as quality condition based maintenance choosing the optimum conditions for detecting the lubricant problem in ball bearing.

Radial Stiffness of Thrust Ball Bearings

2011 ◽  
Vol 490 ◽  
pp. 257-264
Author(s):  
Andrzej Raczyński ◽  
Jaroslaw Kaczor
Keyword(s):  
Computer Program ◽  
Radial Displacement ◽  
Ball Bearing ◽  
Ball Bearings ◽  
Radial Stiffness ◽  
Wear And Tear ◽  
Radial Strength ◽  
Calculation Results ◽  
Special Computer Program ◽  
Bearing System

The paper presents the unusual question of determining the dependency between the radial strength applied to the thrust ball bearing against the radial displacement of one ring to another. Contrary to appearances, the shift may occur in a standard bearing system and consequently it may lead to its premature wear and tear. The article depicts a method of determining this dependency (called ‘radial stiffness’) and shows the examples of calculation results obtained through a special computer program.

Performance studies of textured race ball bearing

2019 ◽  
Vol 71 (9) ◽  
pp. 1116-1123 ◽  
Author(s):  
Vivek Bhardwaj ◽  
R.K. Pandey ◽  
V.K. Agarwal
Keyword(s):  
Ball Bearing ◽  
Dynamic Performance ◽  
Critical Role ◽  
Operating Conditions ◽  
Frictional Torque ◽  
Bulk Temperature ◽  
Back Side ◽  
Ball Bearings ◽  
Content Type ◽  
Long Duration

Purpose The purpose of this paper is to develop an energy-efficient and dynamically improved thrust ball bearing using textured race. A texture has been used on the stationary race of the test bearing to conduct the long-duration experiment for exploring its tribological and vibrational behaviours under starved lubricating condition using micro size MoS2 blended grease. The performance behaviours of the textured race bearing have been compared with conventional bearing (i.e. having both races without textures) under the identical operating conditions for demonstrating the advantages of textured race. Design/methodology/approach Texture was created on stationary race of the test ball bearing (51308) using nano-second pulsed Nd: YAG laser. Performance parameters (frictional torque, temperature rise and vibrations) of textured ball bearings were measured under severe starved lubricating conditions for understanding the critical role of texture in the long duration of the test. S-type load cell and miniature accelerometer were used for measuring the frictional torque and vibration, respectively. Bulk temperature at stationary races (at the back side) of test bearings was measured in operating conditions using a non-contact infrared thermometer. Findings Significant reduction in frictional torque and decrease in amplitude of vibration with textured ball bearing were found even under the severe starved lubricating condition in comparison to conventional bearing. Originality/value There is dearth of research pertaining to the performance behaviours of ball bearings using textures on the races. Therefore, an attempt has been made in this study to explore the tribo-dynamic performance behaviours of a thrust ball bearing using a texture on its stationary race under severe starved lubricating condition for the longer duration of the test.

The Non-Uniform Preloading Effect on Stiffness Behaviour of Angular Contact Ball Bearings

2012 ◽  
Author(s):  
Wenwu Wu ◽  
Jun Hong ◽  
Xiaohu Li ◽  
Yang Li ◽  
Baotong Li
Keyword(s):  
High Speed ◽  
Ball Bearing ◽  
Operating Conditions ◽  
Structural Performance ◽  
Angular Contact Ball Bearing ◽  
Actual Operating ◽  
Bearing Life ◽  
Bearing Stiffness ◽  
Increasing Demand ◽  
Bearing System

With the increasing demand of higher operating speed for bearing system, more challenges have been exposed on the maintaining of the bearing performance. Preloading is an effective method to handle these challenges. Traditionally, the preloading of bearing system has been applied by uniform approaches such as rigid preload and constant preload. However, this treatment may hardly deal with the optimization of preloading problem due to the non-uniformity of the bearing stiffness becomes more apparent under high-speed operating conditions. A novel and practical approach is therefore presented in this paper to incorporate the non-uniformity effect to improve the structural performance of bearing under actual operating conditions. Firstly, the critical relationship between the stiffness behaviour and the non-uniform preload is evaluated for bearing system. The stiffness problem of angular contact ball bearing system is then formulated analytically by Jones’ model. With this approach, boundary conditions are achieved to solve the local contact deformation and predict the bearing life under non-uniform preload. Finally, both the uniform preload and the non-uniform preload cases for bearing system are simulated under various operating conditions. Comparing with traditional methods, the proposed method can provide a better solution in both stiffness and life that will enable a designer to obtain a deep insight on the optimization of bearing system.

Auxiliary Bearing System Optimization for AMB Supported Rotors Based on Rotor Drop Analysis: Part I — Rotor Drop Analysis Method

2016 ◽  
Author(s):  
Jianming Cao ◽  
Paul Allaire ◽  
Timothy Dimond ◽  
Saeid Dousti
Keyword(s):  
Ball Bearing ◽  
System Optimization ◽  
American Petroleum Institute ◽  
Operating Conditions ◽  
Rolling Element Bearing ◽  
Hertzian Contact ◽  
Analysis Method ◽  
Contact Loads ◽  
Auxiliary Bearing ◽  
Bearing System

For rotors supported with active magnetic bearings (AMBs), the auxiliary bearing system or backup bearing system is needed to avoid serious potential internal damaging in the event of AMB loss of power or overload. The evolution of auxiliary systems has been made a priority by the American Petroleum Institute using analytical or experimental methods. In part I of this paper, a detailed rotor drop nonlinear transient analysis method including flexible shaft, rolling element bearing components including inner/outer races and balls, as well as flexible/damped supporting structures is given. A finite element based 6-DOF flexible rotor model is used to indicate shaft motion before the drop (operating conditions) and during the rotor drop event. Un-lubricated Hertzian contact models are used between the shaft and inner/outer races, between balls and races. To avoid heavy calculating time, two different methods to calculate ball bearing contact loads are discussed and the simulation results are compared. These models are applied to predict shaft-race-ball displacements and angular speeds, contact loads and ball bearing stresses during the drop for angular contact auxiliary bearings. This method also can be used to design and optimize the auxiliary bearing system as presented in the 2nd part of this paper.

The Influence of Mounting Compliance and Operating Conditions on the Radial Stiffness of Ball Bearings: Analytic and Test Results

1991 ◽  
Author(s):  
M. F. Butner ◽  
B. T. Murphy ◽  
R. A. Akian
Keyword(s):  
Ball Bearing ◽  
Operating Conditions ◽  
Machine Design ◽  
Ball Bearings ◽  
Test Results ◽  
Resonant Frequencies ◽  
Analysis Process ◽  
Angular Deflection ◽  
Radial Stiffness ◽  
Bearing Stiffness

Abstract Ball bearing stiffness is significantly affected by internal clearance as well as the nature of applied loads and bearing ring mounting compliance. Since their stiffnesses are key to rotor critical speeds, it is important to obtain the most accurate possible radial stiffness prediction for shaft bearings during the machine design analysis process. Quasi-static analysis of spring-preloaded ball bearings predicted reduced radial stiffness when the outer ring is permitted to tilt rather than being assumed restrained from angular deflection. This effect was confirmed experimentally by observing resonant frequencies of a rotor supported on ball bearings of varied internal clearance, mounted with and without spring preloading. Analytic predictions of bearing stiffness are given, and test results presented for comparison.

Detection of Defects at Different Locations in Ball Bearings by Vibration and Shock Pulse Monitoring

2003 ◽  
Vol 34 (3) ◽  
pp. 9-16 ◽  
Author(s):  
N. Tandon ◽  
K.S. Kumar
Keyword(s):  
Pulse Method ◽  
Maximum Load ◽  
Zone Axis ◽  
Ball Bearings ◽  
Shock Pulse ◽  
Low Speed ◽  
Outer Race ◽  
Defect Detectability ◽  
Detection Of Defects

In the present study, the vibrations and shock pulse values of good and defective bearings have been measured. Bearings with one defect and two defects (with different degrees of separation) on the outer race have been used. The position of the defects with respect to the maximum load zone axis was also varied. The study shows that it is easier to detect defects on the outer race of bearings when the defects are in the maximum load zone. The vibration levels and shock pulse values decrease with increase in angle between two defects. The levels decrease as the defects are moved away from the maximum load position. Shock pulse method showed better defect detectability as compared to overall vibration levels. However, at low speed, the shock pulse method has not proved to be as effective as at higher speeds.

Study on Modeling Method and Characteristics of Bearing System with High Rotation Speed

2013 ◽  
Vol 842 ◽  
pp. 391-396
Author(s):  
Li Gang Cai ◽  
Gen Li ◽  
Ya Hui Cui ◽  
Tie Neng Guo ◽  
Yong Sheng Zhao
Keyword(s):  
Ball Bearing ◽  
Rotation Speed ◽  
Modeling Method ◽  
Ball Bearings ◽  
Angular Contact Ball Bearing ◽  
Gyroscopic Moment ◽  
High Rotation Speed ◽  
Stiffness Characteristics ◽  
Load Conditions ◽  
Bearing System

This paper established a general mathematical modeling method based on stress analysis of the angular contact ball bearing under high rotation speed. The influence of the centrifugal force and gyroscopic moment generated in the rotation process is taken into account in this mathematical model. This paper conducted in-depth research for these aspects: the stiffness characteristics of angular contact ball bearings under different load conditions and different rotational speed, internal contact deformation and the change of bearing parameters.

scholarly journals Experimental investigation and thermal analysis of coupler-rocker ball bearing

2020 ◽  
Vol 24 (6 Part A) ◽  
pp. 3781-3793
Author(s):  
Abdullah Jamil ◽  
Bin Baharom ◽  
Alemu Lemma ◽  
Tadimalla Rao
Keyword(s):  
Mathematical Model ◽  
Thermal Analysis ◽  
Experimental Investigation ◽  
Steady State ◽  
Applied Load ◽  
Ball Bearing ◽  
Linear Trend ◽  
Industrial Applications ◽  
Operating Conditions ◽  
Ball Bearings

Ball bearings are widely used in many machineries and industrial applications. Thermal behaviour of oscillating ball bearings is unknown due to its complex pendulum-like motion and is discussed in this research. In this research, the effect of operating conditions of the oscillating bearing performing coupler-rocker motion on the heat generation is experimentally investigated and verified using mathematical model. For this purpose, a coupler-rocker bearing testing rig was designed and fabricated and the test bearing is splash-lubricated in an oil sump. The loading of test bearing was done using two extension springs. The applied load on the bearing was varied from 0 to 750 N while the crank rpm was varied from 1200 rpm to 1800 rpm. Three lubricant grades were used namely, SAE30, SAE40, and SAE50. Experimental results showed that the temperature of coupler-rocker bearing approaches steady-state at about 12 minutes for all cases. The steady-state temperatures at variable conditions are observed to follow a linear trend.

Some Considerations on Vibration Diagnose of Miniature Ball Bearings

2015 ◽  
Vol 809-810 ◽  
pp. 670-675
Author(s):  
Iulian Paul Tărăboanţă ◽  
Viorel Paleu ◽  
Carmen Bujoreanu ◽  
Marcelin Benchea ◽  
Dumitru Olaru
Keyword(s):  
Statistical Analysis ◽  
Medical Equipment ◽  
Room Temperature ◽  
Ball Bearing ◽  
Outer Diameter ◽  
Ball Bearings ◽  
Vibration Level ◽  
Vibration Signals ◽  
Lubrication Conditions ◽  
Fft Analysis

Vibration based fault detection and diagnose analysis is a well established field in machine or monitoring supervision. The vibration diagnose is also suited for the miniature ball bearings monitoring. The typical balls size starts at 3 mm with the bearing outer diameter of maximum 20 mm. Ball bearings of this size are ideal for precision mechanisms, they are able to carry light loads and they are perfect for handheld medical equipment and tools which must be very small but also very precise and durable. The paper presents experiments carried out on a fully instrumented universal CETR micro-tribometer at room temperature. The tested miniature ball bearing, lightly loaded and operating at low speeds, is subjected to dry and lubrication conditions with two different oil viscosities. A comparative study is realized concerning the vibration diagnose potential using the FFT analysis of the bearing acquired signals. Statistical analysis of the vibration signals is a key point in the detection of the overall vibration level of bearings lubricated with oils of different viscosities.

A Linear Theory of Vibrations Caused by Ball Bearings With Form Errors Operating at Moderate Speed

1992 ◽  
Vol 114 (2) ◽  
pp. 348-359 ◽  
Author(s):  
E. Yhland
Keyword(s):  
Theoretical Model ◽  
Linear Theory ◽  
Ball Bearing ◽  
Rotor Dynamics ◽  
Diameter Distribution ◽  
Ball Bearings ◽  
Centrifugal Forces ◽  
Form Errors ◽  
Geometrical Imperfections ◽  
Bearing System

A linear theoretical model is presented for the vibrations of a shaft bearing system caused by ball bearing geometrical imperfections. It is valid for low and medium speeds where ball centrifugal forces can be neglected. The excitation forces from each bearing are calculated and can serve as input to suitable rotor dynamics programs. Imperfections covered are radial and axial waviness of outer and inner rings, ball waviness and diameter distribution, nonuniform cage pocket distribution.

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