Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "bearings" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-8 z 8
    Tytuł:
    Effects of imperfect grooves in full-floating ring bearings on dynamics of a turbocharger rotor
    Autorzy:
    Smolík, Luboš
    Polach, Pavel
    Hajžman, Michal
    Powiązania:
    https://bibliotekanauki.pl/articles/2146577.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    rotor
    dynamics
    uncertainty
    bearings
    wirnik
    dynamika
    niepewność
    łożyska
    Opis:
    Full-floating ring bearings cause nonlinear vibrations of turbocharger rotors, and they have higher hydrodynamic power losses in comparison with rolling element bearings. Both issues can be improved if several shallow axial grooves are machined in the inner surface of the floating ring. The grooves are usually not manufactured precisely in order to keep production costs as low as possible. This work investigates the role of the machining errors on the dynamics of the turbocharger rotor. More specifically, the effects of the precisely-machined grooves on the dynamics of the system are explained. Then the influence of the uncertainties on both vibrations and hydrodynamic power losses in the bearings is investigated.
    Źródło:
    Vibrations in Physical Systems; 2020, 31, 2; art. no. 2020226
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparison of selected point estimators of vibration signals for purposes of fault detection in rolling bearings
    Autorzy:
    Krol, Adrian
    Fidali, Marek
    Jamrozik, Wojciech
    Powiązania:
    https://bibliotekanauki.pl/articles/2146576.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    vibration
    analysis
    bearings
    defects
    diagnosis
    drgania
    analiza
    łożyska
    uszkodzenia
    diagnoza
    Opis:
    Most of machine breakdowns relate to bearing failures thus it is very important to diagnose bearing conditions. The main purpose of the study was to classify the condition of bearings and identify defective ones based on visual inspection and the values of classic parameters of the acceleration signal vibration, such as Peak, RMS, Kurtosis. The results were compared to parameters provided by the SPM method. All vibration parameters were estimated for high pass filtered signals where filters had following cut-off frequencies 0.5; 1, 2, 5 and 8 kHz. Bearings were tested on the laboratory test bench being built at the Silesian University of Technology. Based on the signal analysis and visual inspections it can be stated that there is agreement in the assessment of the conditions between the parameters of the SPM method and the Peak and RMS parameters. It was observed that the sensitivity to the existence of low-intensity defects increases when the vibration parameters are determined for signals in the band above 2kHz.
    Źródło:
    Vibrations in Physical Systems; 2020, 31, 2; art. no. 2020212
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of the sleeve profile on the stability of rotor operating in multilobe journal bearings
    Autorzy:
    Strzelecki, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/127766.pdf
    Data publikacji:
    2016
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    multilobe
    offset journal bearings
    stability of rotor
    łożysko poprzeczne
    stateczność wirnika
    Opis:
    Multilobe journal bearings with the sleeve of the 2-, 3 or 4- sliding lobes of cylindrical profile are applied in different types of rotating machinery. The design of such journal bearings, the number of lobes and oil grooves improves thermal state of bearing at higher speeds and the stability of operation. The paper describes the results of the calculations of dynamic characteristics and determination of stability ranges of simple symmetric rotor operating in the offset types of multilobe journal bearings. The dynamic characteristics of supporting bearings are defined by four stiffness and damping coefficients of oil film. The iterative solution of Reynolds, energy and viscosity equations allows the obtaining of the load capacity of bearings and the required dynamic coefficients of oil film. Adiabatic, laminar oil film and the static equilibrium position of journal were assumed. The oil film pressure, temperature, viscosity fields and the oil film forces were the basis of the bearing dynamic characteristics and stability determination.
    Źródło:
    Vibrations in Physical Systems; 2016, 27; 339-346
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of pad offset on the stability of Jeffcott rotor operating in tilting 4-pad journal bearings
    Autorzy:
    Strzelecki, S.
    Socha, Z.
    Towarek, Z.
    Zakrzewski, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/127935.pdf
    Data publikacji:
    2014
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    tilting-pad journal bearings
    stability of rotor
    łożysko ślizgowe segmentowe
    stateczność rotoru
    Opis:
    Tilting-pad journal bearings are applied in high-speed rotor systems. Excellent stability properties allow obtaining the reliable, vibration free, operation of bearings and rotor. There is still need for better knowledge of such bearings static and dynamic characteristics. In case of tilting-pad journal bearings the stability can be evaluated by the system damping. The system damping gives the damping reserve of the bearings-rotor system and can be obtained by the solution of basic hydrodynamic and rotor motion equations. In this paper the hydrodynamic equations were solved by means of finite difference method. As result, the dynamic characteristics of bearings in form of stiffness and damping coefficients were obtained. These coefficients were the basis for the determination of the system damping.
    Źródło:
    Vibrations in Physical Systems; 2014, 26; 273-280
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The influence of the lubrication on the vibroacoustic signal generated by rolling bearings
    Autorzy:
    Jakubek, B.
    Barczewski, R.
    Jakubowicz, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/128154.pdf
    Data publikacji:
    2017
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    tapered roller bearings
    lubrication
    post-production diagnostics
    łożysko stożkowe
    smarowanie
    diagnostyka poprodukcyjna
    Opis:
    Long-life and failure-free operation of rolling bearings depends on the proper lubrication. Additionally lubrication reduces vibration and noise generated by the operating bearing. However, from the point of view of the post-production diagnostics, lubrication can lead to undesirable masking of damage and manufacturing defects. This article presents the comparison of parameters of vibroacoustic signals generated by tapered roller bearings under different lubrication conditions. The influence of the lubricant on the form of vibroacoustic signals in both amplitude and frequency terms was determined. The premises on the choice of the lubricant for the post-production diagnostics of rolling bearings have also been specified.
    Źródło:
    Vibrations in Physical Systems; 2017, 28; 1-9
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Identification of rolling bearing condition by means of a classification tree
    Autorzy:
    Tabaszewski, Maciej
    Powiązania:
    https://bibliotekanauki.pl/articles/127674.pdf
    Data publikacji:
    2019
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    vibroacoustic diagnostics
    rolling bearings
    classification tree
    diagnostyka wibroakustyczna
    łożyska toczne
    drzewo klasyfikacyjne
    Opis:
    The paper deals with the problem of evaluation of technical condition of rolling bearings on the basis of synchronously measured vibroacoustic symptoms and temperature. Rolling bearings were subjected to accelerated wear under controlled conditions. The values recorded in the study were sound pressure in a broad band including ultrasound (band up to 40 kHz), vibration acceleration in a radial direction, ultrasound in a band up to 100 kHz (processed into audible band), and bearing housing temperature. The identification of the condition was carried out with the help of a supervised learning system. Two conditions were distinguished: fit - examples were obtained in the initial phase of bearing operation in temperature stability conditions, and pre-failure - examples were obtained from fragments of recording just before the occurrence of bearing failure. The CART (Classification and Regression Tree) binary tree method was used to determine the technical condition and significance of particular diagnostic symptoms.
    Źródło:
    Vibrations in Physical Systems; 2019, 30, 2; 1-8
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A small-size stand for vibroacoustic and durability testing of rolling bearings
    Autorzy:
    Wróbel, M.
    Barczewski, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/127755.pdf
    Data publikacji:
    2017
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    vibroacoustics
    rolling bearings
    durability test
    testing stand
    wibroakustyka
    łożyska toczne
    badanie trwałości
    stanowisko badawcze
    Opis:
    A small-size stand for vibroacoustic and durability testing of rolling bearings is presented in this paper. Main purposes and motivations for building this stand were not only to assist research and development works but also to familiarize students with techniques and methods of rolling bearings diagnosing as well as to improve their skills of assessment of rolling bearings technical condition. The project assumptions of the stand, mechanical construction and architecture of data acquisition and analysis system (hardware and software) are described in this paper. Finally there are conclusions about stand’s capabilities included.
    Źródło:
    Vibrations in Physical Systems; 2017, 28; 1-8
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparison of rolling bearings’ diagnosing methods - procedures of damage introduction
    Autorzy:
    Jakubek, B.
    Jakubowicz, M.
    Smułek, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/127677.pdf
    Data publikacji:
    2018
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    tapered roller bearings
    postproduction control
    bearing faults
    bearing damage
    łożysko stożkowe
    kontrola poprodukcyjna
    uszkodzenia łożysk
    Opis:
    The rolling bearings’ diagnosing methods used in exploitation diagnostics are not usually dedicated to the postproduction control. However, this does not mean, that they cannot be used there. A comprehensive comparison of the sensitivity of rolling bearings’ diagnosing methods to occurrence of faults and damage should be based on measurements of new, undamaged bearings and bearings with defects. An accurate determination of the location, size and origin of defects is expected from a set of testing bearings. The paper presents a comparison of three methods of damage introduction: sandblasting, pickling and spark erosion. Procedures for introducing damage into bearing’s races have been described. In addition, race’s geometries and vibration signals generated by operating bearings were compared.
    Źródło:
    Vibrations in Physical Systems; 2018, 29; 1-8
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-8 z 8

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies