Now showing items 1-20 of 35

    • Global Method Using Experimental Data for Characterizing the Lubricants Durability 

      Rădulescu, Alexandru; Rădulescu, Irina; Bălan, Corneliu; Petrescu, Florin; Pogrion Popescu, Nicolette Amelie (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The paper presents a global method for characterizing the durability of lubricants, in order to establish the moment of changing, using objectives criteria. Three types of lubricants, for essence and Diesel engine, have ...
    • Hydrodynamic Effects of Texture Geometries on Journal Bearing Surfaces 

      Tala-Ighil, Nacer; Maspeyrot, Patrick; Fillon, Michel; Bounif, Abdelhamid (Universitatea ”Dunărea de Jos” din Galați, 2008)
      Lately, the expanding range of tribological applications to the microscopic levels has revived interest in this field. Actually, little is understood about the subtle effects of variations of a journal bearing’s profile ...
    • Dynamics of Hip Artificial Joints Wear 

      Căpitanu, Lucian; Iarovici, Aron; Onișoru, Justin; Țigăneșteanu, Constantin; Dima, Marius (Universitatea ”Dunărea de Jos” din Galați, 2008)
      In the present paper the authors try to evaluate, based on the results obtained from experimental and numerical previous studies, the wear evolution in the components of a Total Hip Prosthesis (THP), during the service ...
    • Contact Model for a Rough Surface 

      Cănănău, Sorin (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The paper presents a model for the determination of the contact characteristics, pressure distribution and subsurface stress field at the contact cylinder- plane. The first part of the paper presents the geometrical models ...
    • Experimental Study on Roughness Parameters Variation, During Running – in Period, for a Cylinder-Plane Friction Couple 

      Petrescu, Florin; Davidescu, Anton; Vlase, Monica (2008)
      The studies of various lubrication problems have been recently focused on atypical geometrical and operating conditions (extreme conditions). Among these cases, one can find analyses of HD bearings having surface macroscopic ...
    • Seizure of a High-Speed Three-Wave Journal Bearing 

      Buzescu, Daniela; Pascovici, Mircea (Universitatea ”Dunărea de Jos” din Galați, 2008)
      This paper is focused on the geometry and operating parameters of the bearing experimentally studied at NASA Glenn Research Center by F. Dimofte. It presents two simple thermoelastohydrodynamic (TEHD) models for two typical ...
    • Residual Stresses Effect on Fatigue Life of Rolling Contacts 

      Crețu, Spiridon; Benchea, Marcelin (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The fatigue life tests carried out on two groups of ball bearings point out the positive influence of the compressive residual stresses induced by a previous loading in the elastic-plastic domain. The values of residual ...
    • Hip Joint Contact Pressure Distribution Pand After Triple Osteotomy 

      Laurian, Tiberiu; Marinca, Lucian; Tudor, Andrei; Pârvu, Felix (Universitatea ”Dunărea de Jos” din Galați, 2008)
      A 3−D reconstruction method based on CT scans was used to compute the femoral head coverage for dysplasic hips prior and after reconstruction surgery. The triple osteotomy technique was used to “reorient” the acetabulum ...
    • Wear Behaviour of the AL7175 Alloy under Different Bulk Stress States 

      Buciumeanu, Mihaela; Miranda, A.S; Silva, F.S (Universitatea ”Dunărea de Jos” din Galați, 2008)
      In what concerns the stresses involved in the process, most wear tests (namely those in the pin on disc and the pin on plate configurations) are usually solely concerned with the stress state in the contact originated by ...
    • New Test Facility for Fluid Film Journal Bearings 

      Dimofte, Florin; Ene, Nicoleta M. (Universitatea ”Dunărea de Jos” din Galați, 2008)
      This paper describes a new experimental rig to test journal fluid film bearings. It has been operating at the NASA Glenn Research Center (GRC) in Cleveland, Ohio since August 2006. The rig can apply total radial loads of ...
    • Behaviour of a Hydrodynamic Journal Bearing: Torque Measurement During Start-Up 

      Bouyer, Jean; Fillon, Michel (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The start-up friction coefficient in hydrodynamic bearings, used by engineers in the design of bearings, is most often issued from an approximation. Several studies can be found in the literature on this topic but most of ...
    • On Tribological Behaviour of Thermo-Chemical Treated Steels after Thermo-Magnetic Treatments 

      Papadatu, Carmen-Penelopi (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The paper presents an analysis on two grades of steel, subjected to nitrocarburized or nitrided thermo-chemical treatment after different thermomagnetic treatments. Based on the concept of tribosystem, pairs of steel rollers ...
    • Vegetal Oils as Lubricating Materials 

      Calomir, Camelia; Ștefănescu, Ioan; Chiriță, George (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The success of vegetal oils is related to their biodegradability and reduced toxicity but a wide use is limited by their insufficient stability in time. Biodegradable oils have ecological advantages, being comparable or ...
    • Shear Stability as Oils’ Performance Indicator 

      Ciortan, Sorin; Rîpă, Minodora; Chiculiță, Simona; Spânu, Constantin (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The paper presents a comparative analysis between the shear stability tests results and four ball tests results for some industrial oils. This correlation is used for establishing the way how the mechanical solicitations ...
    • Test-Rig for Pressure Measurements in an Aerostatic Bearing 

      Muscă, Ilie (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The paper presents a test rig for local pressure investigation in an aerostatic or gasostatic bearing system. Using a simple and performant computer assisted measurement device, pressure evolution in lubrication area can ...
    • Analysis of Gear Quality Criteria and Performance of Curved Face width Spur Gears 

      Andrei, Laurentia; Andrei, Gabriel; Walton, Douglas; Dearn, Karl (Universitatea ”Dunărea de Jos” din Galați, 2008)
      For plastic gears, developments in composites and tooth geometry are essential for their selection in power transmissions. In order to enhance the transmissible power level of the plastic spur gears, an arc-shaped tooth ...
    • Nitrogen Influence on Indentation Fracture Toughness of Stainless Steel Coatings 

      Thompson, Mioara; Palaghian, Liviu (Universitatea ”Dunărea de Jos” din Galați, 2008)
      This paper studies some aspects of coatings fracture theory and the possibility of extending Lawn’s equation from Vickers indenter geometry to the Rockwell one. Indentation tests were performed on stainless steel coatings ...
    • Some Aspects about Driving Wheel/Rail Contact in Steady State Interaction 

      Mazilu, Traian (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The driving wheel/rail steady state interaction and the response to harmonic excitation were studied using a complex model for track. The starting point for numerical simulations is the Green matrix of the track. The ...
    • High-Speed Hybrid Angular Contact Ball Bearings Lubricated by Kerosene Mist 

      Paleu, Viorel (Universitatea ”Dunărea de Jos” din Galați, 2008)
      This paper presents some experimental research, carried-out on 7206C hybrid angular contact ball bearings lubricated by oil and kerosene mist. The monitored parameters are the friction moment of the testing bearing, and ...
    • Experiences in Lubrication of non-Natural Gas Fuelled Stationary Engines 

      Novotny-Farkas, Frantz; Bauman, Karin; Leimeter, Tibor (Universitatea ”Dunărea de Jos” din Galați, 2008)
      In Europe, a huge number of generators for electric power, powered by those stationary engines are becoming increasingly popular in regions where these renewable fuel sources are available. Nevertheless, the continuously ...