Development of a method of fuzzy evaluation of information and analytical support of strategic management

Lovska

DZHENCHAKO

et al. 2022

This paper reports the improved load-bearing structure of a hopper car for transporting pellets and hot sinter. In order to increase the strength of the load-bearing structure of a hopper car under the influence of high temperatures from the transported cargo, the use of cladding made of composite material has been proposed. This solution also contributes to a 5 % reduction in the wagon's tare compared to the prototype car. The dynamic load on the load-bearing structure of a hopper car was determined. This study was carried out for the case where an empty wagon was moving over an irregularity between the rail joints. The calculations showed that the studied dynamics indicators did not exceed the permissible values. At the same time, the ride of a hopper car is rated as "excellent". The main indicators of the strength of the carrying structure of a hopper car were determined taking into consideration the proposed improvement. That took into account the temperature effect exerted on the load-bearing structure of a hopper car by hot sinter. It was established that the maximum equivalent stresses occur in the zone of interaction of the girder beam with the pivot beam and are about 290 MPa. At the same time, stresses in the cladding of a hopper car are about 200 MPa, which is 12 % lower than those in a regular structure. Modal analysis was carried out to determine the frequencies and shapes of the natural oscillations of the bearing structure of a hopper car with a composite cladding. The calculation results demonstrated that the first natural frequency exceeds 8 Hz. Therefore, the safety of the wagon is provided. The coefficient of fatigue resistance of the load-bearing structure of a hopper car was calculated. It was established that its value is almost twice as high as the permissible one. That is, the resistance to fatigue of the supporting structure is provided. The research reported here could contribute to ensuring the strength of the load-bearing structures of hopper cars, reducing the cost of maintenance, and increasing the efficiency of their operation.

Section: The Study Materials and Methodsmentioning

confidence: 99%

Determining the features of temperature influence on the load-bearing structure of a hopper car with a composite cladding when transporting pellets to metallurgical enterprises

Lovska

DZHENCHAKO

et al. 2022

“…The solution of differential equations of dynamic loading of covered wagons was carried out in the MathCad software package (Boston, USA) [13][14][15][16]. Starting conditions are assumed to be zero [17][18][19]. It is taken into account that the wagon rests on trucks of model 18-100.…”

Section: Research Materials and Methodsmentioning

confidence: 99%

Improvement of covered wagons of the “East-West” type by sectioning with a partition

Lovska

Klymash

et al. 2021

The dynamic loading and strength of the frame of the “East-West” type covered wagon were determined. To increase the efficiency of operation of covered wagons in international traffic, it is proposed to improve their frames. This improvement consists in using a sectional partition in the body in order to divide it into two separate sections. This allows the transportation of different goods in one wagon, and therefore decreasing empty mileage. The longitudinal loading of the covered wagon frame was determined. The case of shunting impact was considered. The studies were carried out in a flat coordinate system. The loading mode of the frame of the covered wagon in the empty and loaded states was considered. The acceleration acting on the covered wagon frame in the loaded state was 0.37g, empty – 0.42g, which does not exceed the standard values. The wagon motion is rated “excellent”. The main strength indicators of the covered wagon frame were determined. The calculation was made by the finite element method. It was found that the maximum equivalent stresses are concentrated in the area of interaction of the center sill with the bolster beam and amounted to 340 MPa, which is lower than the yield stress of the material. Maximum displacements occur in the middle of the frame beams and are about 12 mm. The natural vibration frequencies of the covered wagon frame were calculated. The research will help to increase the efficiency of using covered wagons in international traffic. Also, the research results can be useful developments in the creation of innovative rolling stock structures

“…When calculating the strength of the load-bearing structure of a covered freight car, a finite element method was used, implemented in the SolidWorks Simulation software package (CosmosWorks), (France) [30][31][32]. In this case, the finite-element model of the bearing structure of a covered freight car was formed from spatial isoparametric tetrahedra [33][34][35], whose optimal number was determined by the graphic-analytical method [36][37][38]. The number of elements in the grid was 608,959, nodes -208,409.…”

Section: The Study Materials and Methodsmentioning

confidence: 99%

Defining patterns in the dynamic load and strength of the bearing structure of a covered freight car with a filler in the girder beam

Panchenko

Vatulia

et al. 2021

This paper reports a study into determining the dynamic load and strength of the bearing structure of a covered freight car under operational modes. A feature of the freight car's bearing structure is that the girder beam has a closed cross-section. To reduce the dynamic load of the frame, the girder beam is filled with a material with viscoelastic properties. Such a solution could contribute to the transformation of the kinetic energy of impact (due to jerk, stretching, compression) into work of viscoelastic friction forces, and, consequently, to reducing the load on the bearing structure. To substantiate the proposed improvement, the dynamic load on the bearing structure of a covered freight car was mathematically modeled. The calculation was performed for the case of joint impacts at shunting. The study was carried out in a flat coordinate system. It was established that the maximum accelerations acting on the bearing structure of a covered freight car were about 37 m/s2. The calculated acceleration value is 3.2 % lower than that obtained for the bearing structure of a covered freight car without filler. The results of calculating the strength of the load-bearing structure of a covered freight car are given. In this case, a finite-element method was applied. The maximum equivalent stresses occur in the zones of interaction between the girder beam and the pivot beams, and amount to 319.5 MPa, which is 8 % lower than permissible. The calculation was also performed regarding other operational modes of loading the freight car's bearing structure. The model of the dynamic load on the bearing structure of a covered freight car was verified according to the F-criterion. The research reported here could contribute to designing innovative rolling stock structures, thereby improving the efficiency of their operation.