The bearing characteristic frequencies (BCF) contain very little energy, and are usually overwhelmed by noise and higher levels of macro-structural vibrations. They are difficult to find in their frequency spectra when using the common technique of fast fourier transforms (FFT). Therefore, Envelope Detection (ED) has always been used with FFT to identify faults occurring at the BCF. However, th...

The project presents an analysis of the vibrational behavior of a deep groove ball bearing with a structurally integrated force sensor. The miniaturized force sensor, accommodated within a slot on the bearings outer ring, provides online condition monitoring capability to the bearing. Analytical and finite element models are developed to predict the sensor output due to bearing dynamic load and...

Rolling bearing is an important part in mechanical system and faults occur frequently with vibration noise. Empirical mode decomposition (EMD) is a tool for nonlinear and non-stationary signals analysis. However, the major drawbacks of EMD are mode mixing problem, ensemble empirical mode decomposition (EEMD) provides a new tool for signal analysis, and it is an improved technique of EMD. In ord...

Abstract Rolling element bearings are important parts of rotating machineries. Any defect in their elements causes vibration and damage. Many signal analysis techniques available for detection diagnosis defects In time domain techniques, various statistical parameters such as RMS, crest factor, skewness, kurtosis etc. used bearings. Bearing related like type, size, shaft speed, radial load affe...

Intracellular H2O2 generation, as a measure of the respiratory burst, was determined after stimulation of neutrophils by immune complex (IC)-bearing human umbilical vein endothelial cells. Under static conditions, neutrophils basically responded to the immune deposits on resting endothelial cells. The rotating shear forces of E0.7 dynes/cm2, corresponding to the physiological flow in postcapill...

Intracellular H2O2 generation, as a measure of the respiratory burst, was determined after stimulation of neutrophils by immune complex (IC)-bearing human umbilical vein endothelial cells. Under static conditions, neutrophils basically responded to the immune deposits on resting endothelial cells. The rotating shear forces of approximately 0.7 dynes/cm2, corresponding to the physiological flow ...

a plain strain analysis of frictional rolling contact on an elastic graded coating is presented in this paper. finite element method is applied to gain an understanding of the stresses and contact zone properties caused during rolling contact. the effects of friction, material stiffness ratio and coating thickness on stresses in contact zone and coating/substrate interface are studied. shear mo...

In the present work, diagnosis of delenoration o f lithium greases The investigatiolls given i n this paper, along wilh the sludy o f used in rolling-element bearings by X-ray diffractornet? (XRD), damagedlcormgated bearing su?faces, have potenlial to diagnose and analysis by X-ray fluorescence spectromet? (XRFS) and atomic lhe cause of bearing failure under the influence of eleclrical fields, ...

Abstract This paper describes a unique experimental set-up constructed for studies of lubricant behaviour in an operating rolling element bearing including situ quantitative measurements film thickness and around the element-raceway contact. The is based on deep groove ball which outer race made sapphire to allow full optical access zone elements are loaded against it. allows direct imaging fil...

The rolling element bearing is a key part in many mechanical equipment. The accurate and timely diagnosis of its faults is critical for predictive maintenance. Vibration signals from a defective bearing with a localized fault contain a series of impulsive responses, which result from the impacts of the defective part(s) with other elements and inevitable noise. Most researches carried out have ...