The practice of operating machinery and equipment that are used in animal husbandry and in the processing of its products has shown low reliability of feed crushers. As of 01.01.2019, in the agricultural enterprises of the Republic of Tatarstan there are about 1200 machines for grinding feed, of which 800 pcs. are hammer crushers. Most of these crushers have a service life of 10 to 13 years and are objects with low reliability. Mostly emergency stops occur due to the destruction of the rotor bearings. In the event of a sudden failure, unplanned repairs and a decrease in production efficiency occur. At the Department of Operation and Repair of Machines of Kazan State Agrarian University, research was carried out and a scientific result was obtained, which was implemented in the adapter to the vibrometer to determine the residual life of rolling bearings. Input data for this device were obtained during operational research and further analysis of the data.
The main causes of malfunction of turbocharged internal combustion engines are high dynamic loads, significant thermal loads in friction zones, wear of turbocharger elements, overheating of components and systems, oil starvation, etc. The reliability of the output parameters of the turbochargers depending on the variable input data values. A condition has been obtained for the trouble-free operation of turbocharger bearings, taking into account oil pumping at engine start, which makes it possible to determine the limits of turbocharger performance and to exclude failure cases with a guarantee. A methodology has been developed for analyzing the sensitivity of the run-out time with oil parameters and turbocharger operation modes, which makes it possible to evaluate the correct operation of turbochargers of modern automotive vehicles in operation. The main test object is K27-145 turbocharger installed on KAMAZ vehicles. The rotor shaft speed, depending on the configuration, is 40.000...120.000 min-1. During the implementation of the experimental work, the working frequency range of rotation of the turbocharger rotor shaft was provided from 25.000 to 75.000 min-1. The levels of variation of rotational speeds were chosen from the condition of providing the maximum frequency - 75000 min-1, the frequency corresponding to average loads - 50000 min-1 and the minimum at which the boost pressure rises to the level of atmospheric pressure - 25000 min-1. The results of the experiment, carried out within a wide range of changes in the input parameters of the oil at the input values of the oil pressure - 0.1 ... 0.4 MPa and the temperatures of the input oil into the bearing - 50 ... run-out from variable input parameters. The run-out time of K27-145 turbocharger rotor at speeds of 25.000, 50.000 and 75.000 min-1 is 10.3…14.8 s, respectively; 28.1…34.4 s; 38.6…47.1 s. The sensitivity of the run-out time with an increase in the rotational speed from 25000 to 75000 min-1 with a variation of 25000 min-1 increases and for the same frequency values it is - 6.6 ... 8.3 s/MPa; 10.6…14.3 s/MPa; 12.0…18.6 s/MPa. Control of run-out time sensitivity parameters allows to determine the quality of the process of assembly and running-in of turbocharger units in the factory, in operation - the correct functioning and resource of the turbocharger. The developed method of rundown control is recommended for machine-building, car service and training organizations.
The article reflects the process of dehydration of brewer pellets, as one of the ways to solve the problem of their utilization in order to obtain a highly concentrated feed for farm animals, which is an urgent task. The purpose of the study is to substantiate the interrelation between the technological and physical properties of the brewer pellets during the separation of brewer pellets into dense and liquid fractions in a continuous vibratory-centrifugal centrifuge and its main design and operating parameters. As a result of the research with the analytical method, process and physical properties of brewer pellets are determined when they are interacting with the perforated rotor blades of a vibratory-centrifugal centrifuge. The equations for the yield of the liquid fraction of brewer pellets through the rectilinear and curvilinear rotor blades are obtained, indicating the interrelation between process and physical properties of brewer pellets, which are necessary for determining the rational basic parameters of the proposed vibratory-centrifugal centrifuge.
The research was carried out in order to develop a mathematical model and a diagnostic complex to determine the residual life of the rotor bearings of hammer crushers. Residual life information is essential for proactive maintenance and to prevent equipment crashes. To achieve this goal, Kazan State Agrarian University (Republic of Tatarstan) carried out calibration studies of the dependence of the diagnostic parameters of vibration on the value of the radial clearances of the bearings. 3610 bearings with different radial clearances (0.02 mm, 0.08 mm, 0.13 mm, 0.2 mm, 0.27 mm) were alternately installed on the rotor of the KD-2 hammer mill, from the drive pulley side and from the fan side) and recorded the vibration parameters. The information was read using a piezoelectric sensor. Signal processing was performed using a VVM-201 vibrometer. The results of mathematical processing of these data are presented in earlier publications. To determine the change in the value of the radial clearance from the operating time in hours, retrospective studies were carried out directly in the agricultural enterprises of the Republic of Tatarstan: “Shaimurzinskoe agricultural enterprise named after A.Sh. Abdreev” of Drozhzhanovskiy region, JSC “Kiyatskoe”of Buinskiy region, the agricultural production complex “Ural”of Kukmorskiy region, etc. The average operating time of the bearings of the rotor of the hammer-type KD-2 forage grinder before the onset of a pre-failure state on the drive side was 1900 ... 2000 hours, on the fan side - 2000 ... 2100 h. Based on the results of the research, the values of the radial clearances and vibration parameters of the rolling bearings of the rotor of hammer crushers were experimentally established, the regularities of the change in the radial clearance of the rolling bearings of the rotor of hammer crushers were revealed depending on the operating time. The developed mathematical models for determining the radial clearance in the rotor bearings of the hammer crusher by vibration parameters and calculating the residual life are implemented in a diagnostic complex consisting of a commercially available VVM-201 vibrometer and a residual life attachment
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