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Finishing surface has an enormous influence on many important physical phenomena such as contact mechanics, sealing, adhesion and friction. In this paper we will present a brief review of contact mechanics and the influence of different process in the finishing surface as the roundness and roughness. For each process step for ball bearing will be explain and different surface parameter will be measure, also the results will be analyze the influence of the process in the finishing surface. A DOE experimental methodology will be use to reach more accurate results with fewer trails and faster response. Also will present new results and a few comments related to a fabrication process.

The clutch actuation system has the function of convert force made by the user on the pedal to a force acting on the clutch fingers. This system is compound with many components and one of than is the clutch release bearing. The clutch release bearing has direct contact with the finger of the clutch and materials in contact suffer a relative motion. In some case this relative motion is desired and other undesired. Thus this contact surface and the relative motion are important parameters to correct operation and to avoid wear. This paper will study the contact mechanic of this system and for this a large bibliographical review will be made and rise. Basic models and simulations will be developed to visualize the behavior of this system and also some experimental test will be done with different contact surface. This work will help to better understand the contact behavior and design contact geometry for minimum wear.

Several mechanical applications require different levels of protection and effective sealing against dirt and external substances assuring no lubricant leakage, low friction, thermal resistance and long operational life. At the field of ball bearing, rubber seal is specially applied due to its particular mechanical behavior. In this study solid rubber viscoelasticity behavior is shortly described including material models and test characteristic parameters like the well-know Mullin effect. Friction, temperature and centrifugal forces are some of the most important parameters to be analyzed. Furthermore a static finite element model using the commercial software ABAQUS is presented. More general discussion is done among the interaction of rubber seal, its metal reinforcement and the adjacent components bringing additional macro uncertain variables to the analysis such as dimensional variation and uncontrolled manufacturing seal shape process.

Hydrodynamic bearings are widely used in rotating machines, being the element responsible for the interaction between the rotor and the supporting structure. Therefore, in order to describe the dynamic behavior of the rotating shafts, it is necessary to know the journal bearings dynamic characteristics. For this reason, this work aims to analyze the influence of three different geometries of journal bearings when operating in a small turbocharger for vehicular application, which implies in high rotation speed and load capacity. In this paper the analysis will be done through the frequency response of the proposed system and the equivalent damping and stiffness coefficients coming from the oil film present in the bearings. These dynamic coefficients are obtained with a spring-damper approach, in order to represent the inherent flexibility and damping of the oil film.

High operating life deep groove ball bearing: optimized geometry reduces friction, energy consumption and noise 50 percent less noise and 35 percent less friction - The significant performance increase offered by this new bearing type is primarily attributable to optimized osculation between the rolling elements and ring raceways. Osculation between the balls and rings has been optimized in order to minimize friction. The improved surface structures of the raceways and balls reduce noise development by 50 percent. In combination with improved surface quality, the design measures reduce friction by up to 35 percent compared with the previous deep groove ball bearing. Other improvements include more effective seals and a riveted steel cage. The innovative HRS seal ensures maximum reliability. Its redesigned lip geometry is optimally adjusted to the recess on the bearing inner ring. In this way, the seal offers more effective protection against loss or contamination of grease.

The development area of the bearing's industry constantly searches for a better efficiency and a lower film oil thickness in surfaces with high roughness under relative motion. In these cases, operational conditions like high loads and temperatures, as well as low safety margins for weight and size, considering the lubricant viscosity, should be taken into account as fundamental design parameters. In order to know better the elastohydrodinamic lubrication effect, firstly, it is necessary to understand deeply and accurately the applied loads on the ball element bearings. For this purpose, the accurate analysis and study of the performance of these machine components is carried out, using analytical methods and giving special focus on the velocities and accelerations involved, as well as different types of loads applied on the ball element and their distribution and consequences during the ball motion inside the bearing rings.

Clutch systems applications require that their components resist to high dynamics and static efforts that should be considered in the development process. These requirements are determined taking account the vehicle application, such as loadcases, materials, life time and environment conditions. In the case of CRB components generally the design is based on contact angular ball bearing. Normally static analysis are performed, computing stresses and displacements, however in this specification the results are checked using static and fatigue safety factors according to the strength assessment evaluation, Germany standard: FKM (Richtlinie - Rechnerischer Festigkeitsnachweis für Maschinenbauteile). Actually more powerful computers have reduced gradativally the cost for industries and with the constant improvements of FE programs, it is possible to simulate the complete assembly using contact interactions to get closer to the reality.