Now showing items 13-32 of 35

    • 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 ...
    • 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 ...
    • 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 ...
    • Industrial Gear Oils from Renegerable Feed Stocks 

      Tănăsescu, Constantin; Petre, Diana; Bogatu, Liana; Antonescu, Niculae Napoleon (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The aim of this research study is to obtain industrial gear oils. The formulation of this type of lubricant is based on vegetable oils or mixtures of vegetable oils with more stable base oils and appropriate additives. The ...
    • Influence of Shear Stability on Oils Behaviour 

      Ciortan, Sorin; Rîpă, Minodora; Chiculiță, Simona (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The paper presents a method to establish a link between the shear stability index and service behaviour of motor oils. A standardized method for shearing stability establishing is combined with appropriated curve fitting ...
    • Influence of the Sliding Speed on the Elastohydrodynamic Regime 

      Seiciu, Petre Lucian (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The study of the elastohydrodynamic (EHD) lubrication regime is characterristic for the heavily loaded gears and can be modeled on a two disk (SAE) rig. It is very important to observe and determine the lubrication regime ...
    • Investigation of Layers Formed Through Selective Transfer with Atomic Force Microscopy 

      Ilie, Filip; Tița, Constantin (Universitatea ”Dunărea de Jos” din Galați, 2008)
      Atomic force microscopy (AFM) has become a versatile tool for investigating local mechanical properties. In addition, through the AFM tip-couple interaction, it is possible to study the effects of perturbations and ...
    • 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 ...
    • 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 ...
    • 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 ...
    • Research Rearding of Composite Materials under the Influence of Abrasive Wear 

      Florea, Carmen; Florea, Alexandru; Chivu, Mioara (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The method described in the paper will allow estimating the composite materials performances with different structures and various working conditions, with a view to estimate useful life of technological equipments parts ...
    • 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 ...
    • 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 ...
    • 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 ...
    • 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 ...
    • Study of Wear Evolution for a Hydraulic Oil Using a Four Ball Tester 

      Spânu, Constantin; Rîpă, Minodora; Ciortan, Sorin (Universitatea ”Dunărea de Jos” din Galați, 2008)
      Time is crucial for the wear of materials. Time of an experiment must be long enough to obtain an observable wear but no so long to make the experiments expensive. For determining anti-wear properties of the hydraulic oils ...
    • 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 ...
    • The Effect of Wiberg Angle on the Contact Pressure Pistribution in Natural and Artficial Joint 

      Tudor, Andrei; Parsu, Carmen; Sorina, Opriș (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The analogies and differences between the mechanical joints and the biological ones, in the presence of relative motion, are based on the pressure distribution. The paper analysed a numerical model of the pressure distribution ...
    • The Influence of the Applied Load on the Friction Coefficient of the Sintered Iron-Base Bearings 

      Teișanu, Cristina; Gheorghe, Ștefan; Tudor, Andrei; Ciupitu, Ion (Universitatea ”Dunărea de Jos” din Galați, 2008)
      In the recent years the iron base sintered bearings production was considerable increased at the expense of the copper based ones, due to the low cost and availability of the iron powders as well as the higher strength. ...
    • The Tool to Model through Micro Strain and Micro Cutting 

      Tache, Antonio; Tache, Carmen (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The cutter wear is analised by a single hard fixed particle (inclusion) in brittle material. The shakedown pressure of the inclusion contact is directly proportional to shear field stress of the cutter surface and is ...