Abstract. In the article it was shown that one of the factors that significantly affect the mechanism of rolling friction is the mechanism of micro slippage between the balls and the raceway bearing. In this connection was defined the character of friction torque distribution along the contact area of contacting elements.
The article describes the process efficiency of ultrasonic mechanical stabilization of details in comparison with the conventional thermal treatment. It is shown that ultrasonic treatment enhances the productivity and quality of manufactured details. As a result of the proposed stabilizing treatment the relaxation of residual stresses, the required geometry, such as waviness and ovality, as well as necessary mechanical properties are ensured.
ЭКСПЕРИМЕНТАЛЬНОЕ ИССЛЕДОВАНИЕ ПРОИЗВОДИТЕЛЬНОСТИ БЕСЦЕНТРОВОГО МЕТОДА СТАБИЛИЗАЦИИ КОЛЕЦ ПОДШИПНИКОВРассмотрена технология снятия остаточных напряжений бесцентровой обкаткой колец под-шипников. Представлены результаты эксперимен-тальных исследований влияния технологических параметров наладки оборудования на производи-тельность обработки. Получена эмпирическая зави-симость такта выпуска от угла перекрещивания осей валков и их частоты вращения. Установлена зависимость числа циклов нагружения от угла пе-рекрещивания осей валков и величины упругой технологической деформации обрабатываемых ко-лец.Ключевые слова: бесцентровая обкатка, кольца подшипников, деформация, наладка, произ-водительность. A.F. Balaev EXPERIMENTAL INVESTIGATION OF CENTERLESS METHOD EFFICIENCY IN RACER STABILIZATIONThe relaxation of residual stresses in racers in the course of their operation results in product life decrease. To decrease residual stresses one usually uses thermal tempering which possesses high power consumption and low productivity. A thermal tempering substitution for a method of racer centerless rolling is called upon to eliminate these drawbacks. For realization of a centerless rolling there is used a three-roll device with axles of two rolls turned around a vertical plane for an adjustable angle ensuring a longitudinal and rotary motion of racers. The third roll loads a racer in such a way that an elastic deformation could arise in areas of a contact with three rolls. A rotation transfer to a racer from a driving roll on the whole of a surface rolled. An oscillatory character of elastic deformations of a racer results in the relaxation of residual stresses. There is carried out an experimental investigation of centerless running-in productivity. On the basis of experimental results obtained there is defined a dependence of an exhaust stroke and an amount of racer loading cycles upon an angle of the crossing of roll axles, rotation frequency of rolls and a value of technological deformation. As a result of two methods comparison it is defined that the centerless running-in consumes power 50 times less and is efficient more than 5 times of thermal tempering.
The substantiation of the new technology of multi-cycle racer running-in is shown. A technological method for racer resi-dual stresses removal by means of multi-cycle centerless running-in is described. For the computation of running-in basic time which is necessary for the complete removal of residual stresses there is developed a simulator. A simulator takes into account geometrical and mechanical conditions of the contact of rollers and a racer, physical-mechanical and geometrical parameters of a racer. On the basis of the simulator obtained there is carried out an investigation of the dependence of residual stress upon the duration of racer multi-cycle running-in for various stressed states. It is established that for the efficient stress removal the running-in time must be optimum. If time is lesser than optimum, then there is no a complete removal of residual stresses. At processing time longer of optimum one after a complete removal of residual stresses the accumulation of new residual stresses takes place.
The paper reports the substantiation of the stabilization technology for geometrical parameters of elastic plates in pressure sensors carried out by means of residual stresses affected by ultrasonic oscillations. For the confirmation of the efficiency of the developed ultrasonic stabilization technology in accordance with the procedure described the experimental investigations are carried out. The results of the experimental study are presented by the equation of regression and diagrams of residual stresses dependences upon technological factors. Amplitudes of ultrasonic oscillations, a static force of tool pressure and machining duration were assumed as variable technological factors. High productivity and efficiency of the ultrasonic technology for elastic plate stabilization are proved experimentally. As a result of the experiment there are defined rational values of ultrasonic processing modes for specific geometrical and physical-mechanical parameters of a plate.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.