Włodzimierz Makieła

DEFINING THE CRITERIA TO SELECT THE WAVELET TYPE FOR THE ASSESSMENT OF SURFACE QUALITY

The paper deals with one of the most important problems in the wavelet analysis – the methodology for mother wavelet selection. In this study, the surface texture of machine parts was assessed applying a wavelet transform. The calculations involved in roughness profile evaluation were based on three selection criteria: an autocorrelation test, a cross-correlation function and an entropy-based test. All the calculations and diagrams were produced using the Wavelet toolbox of the MATLAB package.

Creation of Mathematical Prescription of Residual Stress Depending on Various Cutting Conditions

Article deals with problematic of internal residual stress after machining depends on various cutting condition. In article is presented influenced of cutting conditions to quality of internal layers by defining values of residual stresses. Method use to evaluate values of residual stress was RTG diffraction. Material used for experiment was steel C45 and type of machining was up milling for various parameters such as spindle speed, feed rate and depth of cut.

Application of Wavelet Transform to Determine Surface Texture Constituents

The paper studies the possibility of application of a two-dimensional wavelet transform to analyse surface texture signals. The tests were directed at determining the impact of wavelet transformation parameters in the scope of using the wavelet analysis to separate the constituents of measured surface irregularities. The surface roughness signals obtained as a result of the Gaussian filter application and after wavelet decomposition were compared. Based on the obtained results, it was concluded that a wavelet transform may be used to separate 3D surface texture constituents.

Analysis of the Impact of Ball Bearing Track Waviness on Their Frictional Moment

Frictional moment is one of the parameters that determine the time and quality of working bearings. Therefore, it is important that it is possible to accurately predict the value of the frictional moment. This article analyses the impact of the track waviness on the frictional moment. In the research, a correlation analysis of selected wavelength parameters and frictional moment was performed and frictional moment. Those parameters wavelength are not included in the models used to determine the theoretical value of the frictional moment.

The analysis of the impact of the design parameters on the friction torque in ball bearings

One of the many factors influencing the frictional moment in the bearings are construction parameters. These parameters include curvature ratio (the ratio of the radius of the track to the diameter of the ball) and the accuracy of the track shape. Although these factors influence the frictional moment, they are not included in the model used to determine the theoretical frictional moment. In this article, an analysis was carried out to determine the quantitative impact of the curvature ratio at the frictional moment in ball bearings. In order to * Kielce University of Technology, Department of Manufacturing, Engineering and Metrology, al. Tysiąclecia Państwa Polskiego 7, 25-314 Kielce, Poland, tel. 41 34-24-434, e-mails: adamczak@tu.kielce.pl; lgorycki@tu.kielce.pl; wmakiela@tu.kielce.pl. T R I B O L O G I A 5-2016 12 determine the quantitative effects of this parameter, a linear regression analysis was carried out on five groups of bearings and under five measuring parameters (the rotational speed, the radial and axial load and curvature ratio of the inner and outer ring).