The tribology of the car: Research methodology and evaluation criteria

From a position of structural and power theory of friction and wear, it is possible to apply the method of Contact Electrical Resistance (CER) for a complex research of the processes in a-zone of frictional contact. The purpose of this paper is to present a construction of friction node and drive mechanism of friction machine. As a result of the reported study the regularities of changes the CER and tribomechanical indices for non-metal friction couples in dependence on loading parameters and lubricating media were received. Also, the method of determination the range and level of normal wear and critical points of transmission to damage in accordance with kinetics of wear changes is proposed. The interrelation between geometrical, physical and mechanical properties, processes of formation, transformation and destruction of secondary structures, tribotechnical indices and CER in dependence on operation regimes of friction couples

Torsional oscillations of an auger multifunctional conveyor’s screw working body with consideration of the dynamics of a processed medium continuous flow

Introduction. The aim of the article is a mathematical model of vibrations of working part of screw conveyer for transporting friable loads taking into account the changes of closeness of the processed environment, speed of circulation of screw, weight while appearing of the phenomenon of resonance. Materials and methods. It is recesrced the turning vibrations of spiral working part of screw multifunctional conveyer, which appeare as a result of action of processing environment. The recerch was carried out by mathematical modelling method. Results and discussions. The limiting factors which complicate a design are the unevenness of the division of environment along the length of screw; a body makes flexible vibrations; the motion of the processed environment along the working screw causes the small vibrations of bend, causes appearance of “additional forces”. For providing the authenticity of mathematical model ti has been introduced the next suppositions: the working part of screw is turned with the permanent angle speed around its longitudinal which in the undeformed position coincides coincides with an axis OX; the transversal transferring of neutral axis of working screw at the arbitrary moment in perpendicular direction of its undeformed position is determined by the vector (in relation to the fixed frame of reference of OXYZ); the continuous stream of processed environment,while its weight changes on unit length slowly along a screw and moves with permanent relative (in relation to working screw) speed. A mathematical model takes into account the limitation and supposition for the existent screw conveyer with the length of 2,5 and 3 m, which is used for moving the friable loads with the consistence of 10, 20, 40 kg/m. The alternative parameters are the length of the screw,the consistence of the processed environment, the speed of circulation ofthe screw , weight On the basis of model the dependences of amplitude of vibrations on the lengthof screw , cosistence of the processed environment, the speed of circulation of the screw, weight are built. Conclusions. A mathematical model allows to improve the process of development and designing of the screw conveyers of the friable loads providing the reliability of process of transportion and system “the processed environment – the screw working part”

The tribology of the car: Research methodology and evaluation criteria

From a position of structural and power theory of friction and wear, it is possible to apply the method of Contact Electrical Resistance (CER) for a complex research of the processes in a-zone of frictional contact. The purpose of this paper is to present a construction of friction node and drive mechanism of friction machine. As a result of the reported study the regularities of changes the CER and tribomechanical indices for non-metal friction couples in dependence on loading parameters and lubricating media were received. Also, the method of determination the range and level of normal wear and critical points of transmission to damage in accordance with kinetics of wear changes is proposed. The interrelation between geometrical, physical and mechanical properties, processes of formation, transformation and destruction of secondary structures, tribotechnical indices and CER in dependence on operation regimes of friction couples