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Рассмотрена задача LTCA тяжелонагруженной низкоскоростной многопарной спироидной передачи с учетом влияния упругого контактного и изгибно-сдвигового и упругопластического контактного взаимодействия зубьев колеса и витков червяка. Задача LTCA упругопластически нагруженной передачи рассмотрена как комбинация двух задач: анализа - вычисление параметров нагруженного контакта; синтеза - поиска требуемой геометрии. Обоснован отказ от метода конечных элементов (МКЭ), обычно широко применяемого для решения задач LTCA. Приводится описание разработанного алгоритма расчета распределения нагрузки с учетом упругого и упругопластического характера многопарного контакта спироидной передачи, имеющей сложную пространственную геометрию. Предложена модель расчета величины пластической деформации в зависимости от первичной оценки перемещений в упругом контакте. Показано влияние погрешностей изготовления передачи на уровень нагруженности отдельных ее пар зуб - виток.

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The paper presents the analysis of heavy-loaded low-speed multi-pair spiroid gears under the effect of elastic contact, bending and shearing, and elastoplastic contact interaction of spiroid gearwheel teeth and spiroid worm threads. The main stages of the developed algorithm for analysis of load distribution and plastic strain of flanks with account of elastic and elastoplastic contact conditions, multi-pair contact and macro-roughnesses on flanks are described in short. At elastoplastic contact the zones of plastic contact on flanks of spiroid gearwheel teeth are determined and the value of plastic strain is analyzed. The flanks of the spiroid gearwheel teeth and worm threads are represented in the algorithm as the set of segments (cells) with coordinates of centers determined with account of the analyzed factors that influence the load distribution in spiroid gearing. These factors are the errors of manufacturing and (or) assembly, micro-roughnesses, and deformations of spiroid gear supports. The paper gives the numerical results of research of the real spiroid gears of gearboxes for pipeline valves (PV) at elastic and elastoplastic contact represented as summary tables and diagrams of contact stress distribution along contact areas and of plastic strain, that show the workability of the algorithm. The presented numerical results of the algorithm functioning are well agreed with the experience of operation of spiroid gears and can be applied for analysis of load-carrying capacity of spiroid gears.

The subject of the study is the flexural fluctuations of the rotors of knife refiners. The dynamic and mathematical models of rotors of disk mills are developed. As a result of research, a method for vibration calculation of rotors is proposed and tested. Research was also conducted using the Ansys software package. The error in determining the lower frequencies of free fluctuations of the mill rotors does not exceed 9%. Failure to take into account the elastic compliance of the rotor bearings leads to an error in determining the frequencies of free flexural fluctuations by no more than 15%, and the gyroscopic moment increases the above frequencies by no more than 25%. The cantilever arrangement of the disk reduces the frequencies of free fluctuations of the mill rotor by 1.1 - 1.4 times in comparison with the inter-support arrangement. The developed calculation procedure can be used in other industries, for example, mining and metallurgy.