The effect of local changes in the surface hardness of the end surfaces of teeth of coarse-grained gear transmissions mining machines. Represented by patterns of change of the surface hardness is not the type of reference to the loading. The estimation of the value of destruction of samples. Proposed to assess the remaining amount of coarse-grained gears with consideration of changes in the local surface hardness developed technique.
To date, there is need to review the existing rigid system of preventive maintenance and the transition to a more progressive system, which provides maintenance and repairs on its actual state, in which the need for repair work is based on a preliminary examination and the results of the diagnosis and monitoring of major nodes excavator. Pays special attention to the concept of TPM (Total Productivity Maintenance) for the maintenance of mining excavators.
In article the review of methods of a theoretical estimation of a resource of elements of cars is presented. Perspectivity of the thermodynamic approach is shown at the analysis of an expenditure of a resource by system elements. Presented a probabilistic approach in determining the energy source.
The reasons of an emergency stop of tubular furnaces is destruction of bearings in support of the furnace, bearings and cogwheels in mechanical transmission, failure the electric motor, infringement of integrity of the case of the furnace and it brickwork. In article possibilities on forecasting of a residual resource of bearings of support and transmission are considered, principles of construction of a complex from system of monitoring of a condition and automatic systems of greasing of bearings are offered.
Рассматриваются способы повышения срока службы открытых зубчатых передач на примере привода шаровой мельницы. Приведены результаты внедрения автоматической системы смазки и предложены пути повышения эффективности ее использования.
Методом акустической эмиссии в ультразвуковом диапазоне частот (20-300 кГц) проведены измерения интегральных показателей трения и их сопоставительный анализ для пары трения металл – металл со смазкой в виде индустриального масла, наполненного традиционными присадками (уголь) и наноструктурированными порошками на основе алюминия. Оценено влияние твердых присадок на смещение участка сухого трения на кривых зависимостей показателя трения от давления в зоне контакта. Выявлен наноструктурированный образец на основе алюминиевой пудры ПАП-2, содержащей на поверхности двухкомпонентную нанопленку катионных ПАВ, который улучшает антифрикционные характеристики индустриального масла И-20 в 4-7 раз. Развиты представления о механизме действия присадок на антифрикционные свойства масла.
Нагрузочная способность масел определяется их смазывающей способностью. Ввиду недостаточной смазочной способности масел для пар трения, эксплуатируемых в условиях граничной смазки, распространено адсорбционно-коррозионно-усталостное изнашивание, в связи с чем важным является обоснованный выбор масел для трансмиссий горных машин. Предложен экспресс-способ сравнительной оценки смазывающей способности масел.
Для диагностирования трансмиссии горной машины без установки дорогостоящих датчиков может быть использована пилотная диагностика по параметрам питания электродвигателя, основанная на предположении, что большинство возмущений, возникающих в трансмиссии и влияющих на момент сопротивления, преодолеваемых двигателем, сказывается на изменении потребляемой электродвигателем мгновенной мощности.
Применение комбинированного смещения при проектировании зубчатых передач позволяет значительно расширить область существования зацепления с нестандартным радиальным зазором. Представлено влияние параметров реeчного производящего контура на область существования зацепления. Дано сравнение 3D области существования зацепления с различными числами зубьев.
For timely maintenance and repair of mining equipment, as well as to reduce the number of emergency stops, modern diagnostic and monitoring devices are required. The article presents a comparative analysis of vibration and acoustic emission diagnostics methods.
It is shown that the use of combined displacement in gear design makes it possible to considerably expand the area of existence of meshing with non-standard radial clearance. The influence of parameters of the rack-and-pinion producing contour on the area of existence of the meshing is presented, the technology of realization of the tantan-gential displacement in gear cutting is described.
Application of the combined displacement when designing gears allows to considerably expand the area of existence of meshing with non-standard radial clearance. The influence of the parameters of the rack-shaped producing contour on the region of the meshing existence is shown, the technology of the tangential displacement realization during gear cutting is described.
Extensive opportunities to influence the properties of involute gears are available with combined displacement of tooth profiles - a combination of radial and tangential displacements, including the use of cutting tools with a standard initial contour. In particular, by combined displacement, the bending strength and wear resistance of cylindrical gear teeth can be increased by one and a half to two times, which is commensurate with material replacement.
Information is presented about the milestones of the establishment and reforms of the Faculty of Mining and Mechanical, and later of the Faculty of Mining and Electrical Engineering. With the establishment of the Mining School in 1773 seven classes were opened there, including mechanical and drawing. The first subjects, taught in the College, were mine mechanics, theoretical mechanics and hydraulics. The faculty of Mining mechanics as an independent structural unit was founded in the autumn of 1919. Its appearance was connected with the necessity to train specialists in mining engineering, special equipment for mines, dressing mills and mining plants. It was the first in the country mining mechanical faculty. The glory of the faculty consisted of famous scientists A.P. Herman, F.N. Shklarsky, L.B. Levenson, V.V. Chernyavsky, A.A. Shchukin, V.I. Gerontiev. The team of teachers, researchers and graduate students aims at closer cooperation with various mining enterprises and companies, which will undoubtedly have a positive impact on improving the quality of training.
