Characterization of NRRO in a HDD spindle system due to ball bearing excitation

Abstract The effects of the uncertainty of angular misalignment on the wear of angular contact ball bearings in the spindle system are investigated. The wear model of bearing raceways is derived based on Archard model. The angular misalignment caused by mounting error is assumed to comply with normal distribution, Monte Carlo method is used to extract angular misalignment sample. Based on the spindle system model, the spinning speed, pitch angle and contact force of ball elements in each angular contact ball bearing are calculated. The wear depth of bearing raceways is analyzed. The results show that the uncertainty of the initial angular misalignment leads to significant dispersion of wear depth of ball bearings, but the dispersion degree is related to spindle speed, angular misalignment cases, and bearing mounting position. Increasing the spindle speed increases the wear depth but decreases the wear depth dispersion.

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Synthesis and Performance Characterization of Nanolubricants Proposed for Heavy Load Ball Bearing

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.54.75 ◽

2018 ◽

Vol 54 ◽

pp. 75-87 ◽

Cited By ~ 1

Author(s):

S. Nallusamy

Keyword(s):

Ball Bearing ◽

Load Carrying Capacity ◽

Analytical Validation ◽

Transfer Coefficients ◽

Heavy Load ◽

Heat Transfer Coefficients ◽

Load Carrying ◽

And Performance ◽

Convective Heat Transfer Coefficients

Currently, nanofluids have been found to have enriched physical and thermal properties such as thermal conductivity, viscosity and convective heat transfer coefficients. The aim of this research is to analyse the performance characteristics of punga oil and plastic oil based nanolubricants. The nanoparticle of graphite with 0.1% weight was added to the base oils. Hydraulic oil of VG32 is used as standard oil to compare the performance with the nanolubricants. Basic properties such as viscosity, flash and fire point were measured for the prepared nanolubricants. Coefficient of friction for the selected oils was measured with help of reciprocating friction monitor and load wear index was also measured with the help of four ball tester. The performance of these oils for load ball bearing lubrication was carried out numerically with the help of Comsol software and its analytical validation was done with the help of MATLAB software. From the observed results it was found that, the power loss was decreased by about 77.4% and 78% by plastic oil and plastic oil based nanolubricant respectively and load carrying capacity was also decreased by about 78.3% and 78.8%.

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DYNAMIC CHARACTERIZATION OF BALL BEARING IN TURBINE PROPELLER USING BUMP TEST METHOD

SINERGI ◽

10.22441/sinergi.2021.2.004 ◽

2021 ◽

Vol 25 (2) ◽

pp. 135

Author(s):

Monika Audiya Pratiwi ◽

Muhammad Ikhsan ◽

Rio Duzan Octavianto ◽

Abdul Hamid ◽

Subekti Subekti

Keyword(s):

Wind Turbines ◽

Ball Bearing ◽

Test Method ◽

Vibration Modes ◽

Dynamic Characterization ◽

Local Vibration ◽

Maintenance System ◽

Rotating Equipment ◽

Equipment System

Bearing is an essential component in a mechanical rotating equipment system. It is no less important than lubrication to prevent wear is very important to consider in the mechanical maintenance system of rotating equipment. Bearing wear is one of the problems in wind turbines that will increase maintenance costs, shorten the wind turbines' lifespan, and cause the component or overall damage to the wind turbine. The latest technology has provided instruments for analyzing the damage of elements in a bearing according to the caused vibrations. Therefore, this study was performed on Ball Bearing Turbine Propeller to identify the dynamic characteristics of Ball Bearing with and without lubrication. The test was carried out using the Bump Test method applied in three measured parts: X, Y, and Z axes. The measuring instrument which was used was Fast Fourier Transform (FFT) Analyzer (Ono Sokki) and the data were analyzed using MATLAB. It was identified that the application of oil could reduce the amplitude and decrease the frequency. Personal frequency appearing more than once indicates the existence of global vibration modes. The frequency which only appears once in the measurement spot indicates local vibration modes. The highest frequency both after and before the application of oil was found in the Y-axis.

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