The paper contains the results of theoretical studies of loading parameters of carrying and tractive belts of a multidrive belt conveyor in case of accidental sliding deviations of electric motor drives. The direct effect of a random combination of sliding deviations on the working life value of the carrying belt is shown. The justification for taking into account the actual parameters of belt loading cycles when calculating their working life during the process of designing multidrive belt conveyor within each combination of sliding deviations is given. The paper demonstrates inconsistency of the approach regulating the determination of the skewness ratio of loading cycles as a value inverse to the drives traction factor.

The paper proposes a mathematical model of operation of stacker belt conveyors of mobile road-building machines with tracing control of belt tension. This model allows one to evaluate the operation processes of the conveyor taking into account the variation of the rolling resistance coefficient of the belt on the dumping track, as well as to determine parameters of the tracing tensioning devices with a view to further selecting the appropriate driven equipment. On the example of a stacker conveyor of a mobile power washer, construction features of the proposed mathematical model are shown. Some regularities of the operation of short conveyors, which make it possible to increase efficiency of the designing process, are identified.

Mobile rope systems designed to carry out loading and unloading and transport and transfer operations in noequipped or hard-to-reach areas and ensuring the prompt deployment of the necessary technological means are a promising type of lifting and transport equipment. The article deals with the layout of the main technological equipment of one of the constructive variants of a mobile rope system on a base multi-axle wheeled chassis of high carrying capacity and performance. A variant of the layout with the central location of the end tower attachment point for supporting the leading rope pulley with a carrying rope on the base chassis frame is considered. Mathematical models have been developed that ensure the kinematic and power analysis of the kinematic scheme of the hydraulic mechanism for installing and fixing the end tower. The analysis of the influence of the main structural dimensions of the indicated mechanism on the dimensions of the mobile rope complex in the transport position, as well as on the force factors arising during the operation of the rope system is carried out. The necessary conditions have been established that must be met when designing a rope system to ensure the regulatory requirements for the movement of a mobile complex on automobile roads of the general using. The conditions for the location and length of the drive hydraulic cylinder of the end tower, which ensure the necessary movement of the tower from the transport position to the working position, have been established and analyzed; the presence of a significant zone of inadmissible location of the hinged assembly for attaching the hydraulic cylinder rod to the metal structure of the end tower has been revealed.

Reducing vibrations transmitted to the operator of construction and road vehicles through his chair is an urgent task, since significant vibrations lead to human diseases, reduce productivity and accuracy of work performed by machines, etc. Advantages for use in vibration protection systems are mechanisms with quasi-zero stiffness, in which no hydraulic or electromagnetic elements are used. Among them, vibration protection systems based on a package of Belleville springs, having a relatively simple design, can be distinguished. In them, unlike other mechanisms with quasi-zero stiffness, the functions of creating positive and negative stiffness are combined in the same structural elements — Belleville springs. The static characteristic of a Belleville spring with certain ratios of its dimensions already contains a section of quasi-zero stiffness of small length. The cup spring package allows you to increase the size of the quasi-zero stiffness area of the vibration-protective system of the armchair of a human operator of a construction or road machine to the required values of the order of several tens of centimeters. Certain difficulties arise in connection with the location of the center of the quasi-zero stiffness section of an individual disk spring in the middle of its deformation range when the spring is flat. This leads to the necessity of either using custom-shaped springs with collars at the top and bottom, or, as suggested in this article, using intermediate ring washers between the springs. The article provides a methodology for determining the number and size of springs and washers that provide a certain size of the quasi-zero stiffness section of the entire vibration protection system. It also provides a methodology for determining the mass of the entire package of springs with washers. It has been established that reducing the diameter of the springs requires reducing the thickness of the metal to provide a section of quasi-zero stiffness. Because of this, when the diameter of the springs is reduced by a factor of five, the mass of the mechanism can be reduced by a factor of twenty-four.

The article deals the issues of constructing by according to previously developed methods of the model that describes the heat balance in the unit “hydraulic puller-drill shaft”, which is used in jet-grouting devices. Two main groups of materials used in similar structural units for the manufacture of sealing elements, which include elastomers and thermoplastics, are analyzed. The requirements are described and the operating conditions of these materials are indicated. Separately, attention is focused on the range of operating temperatures of materials of sealing elements for hydraulic pullers. The algorithm used for the computational experiment with the indication used in the calculation, the software package that allows to solve applied problems of strength, heat transfer, etc. A solid model of a section of a drill shaft with a meshing of finite elements is presented. It is shown that the distribution of the thermal field in the elements of the hydraulic cutter of the drill head, obtained as a result of the finite element calculation, that arises during operation and factors that significantly affect the temperature distribution are identified. The assumption is substantiated that the materials currently used in hydraulic pullers for jet cementation of soils do not withstand the heat load that occurs in such ultra-high pressure devices during their operation.

Road construction works have quite unfavourable conditions in terms of wear and tear. This situation is more caused by dry friction and the prevalence of abrasive wear. Therefore, parts that contact the working environment can be classified as fast-wear. One of the most effective ways to improve durability here is to use surface hardening. It is possible to use a cheap material on the surface of which a layer with improved mechanical properties is formed. The work deals with the use of grey iron with a reinforced layer to solve the above problem. The purpose of the work is to study the applicability of grey cast iron with a strengthened layer in the structures of working tools of construction and road machines. The work carried out experimental studies of wear resistance of parts made of ferrite-pearlite grey cast iron with a strengthened layer. On the basis of the calculations, the durability of the parts of the working tools containing wear-resistant inserts from the material under consideration is determined, it is shown that the use of the proposed solutions allows to obtain results comparable to the light high-strength iron and white iron. Issues of evaluation of weldability of wear-resistant inserts and steel base are also considered in the work. It is shown that it is possible to obtain a weld joint using manual arc welding. The results of the evaluation of economic ef-selectivity showed that the cost of bending wear-resistant elements from grey iron with a strengthened layer was lower than the use of hardening techniques (for example, build-up).

Stability of a wheeled vehicle against overturning characterizes its ability to maintain a given position during the movement on the slope. One of the most important performance indicators of a wheeled vehicle on a slope is its lateral stability, which characterizes its ability to work on slopes without tipping over. Ensuring reliable lateral stability of wheeled vehicles is the most important condition for their trouble-free operation. The paper deals with mathematical and simulation modeling of tricycle stability against tipping on a slope. The tricycle can lose stability. The most dangerous mode of movement of a wheeled vehicle is driving on a slope, which can cause loss of stability. It is noted that the influence of structural and operational factors creates a tipping moment, which worsens the stability of the tricycle against tipping on the slopes. Studies have shown that increasing the stability of the tricycle against overturning when moving along the slopes in a transverse direction, can be achieved by shifting the center of mass from the longitudinal axis of the tricycle towards the elevation of the slope, i.e., by tilting the frame of the relative rear bridge in a perpendicular plane relative to the direction of movement towards the elevation of the slope, such a change in parameters contributes to increasing the stability against overturning on the slope, since the restoring moment will increase relative to the overturning moment.

The article proposes the development of a security system program that controls the influence of non-regulatory external factors for the accident-free technical installation of the overturned crane in an extreme situation (working away from stationary bases). It is shown that it is advisable to install a crane to prevent the rollover of the lifting crane: the loader and the devices that control the safety of the crane, which in the process of operation should be in cooperation. The developed technique of modeling the crane lift device allowed to develop a software product in the programming language Pascal. The security system of the installation being developed, visualization, and a common program for the programable logical controller were carried out with the help of the CodeSys 3 software complex. The proposed simulation technique for a crane lift device is confirmed by the visualization of a common program for a programable logical controller using different programming languages.

Existing methods of assessing the influence of factors allow to determine this influence indirectly without taking into account the speed (intensity) of their influence and the relationship between them. The article proposes a method of assessing the complex impact of significant factors on the failures of cranes, the relationship between which is presented in the form of a kinetic system, changing over time depending on the change of any active factor. The accumulated statistical material of accidents on cranes of different kinds are the initial data in the conduct of studies to assess the cumulative effect of various factors on the performance of crane equipment. The proposed methodology will take into account the intensity of the changes in factors associated with their change. This takes into account the kinematic state of the current factors, which is determined by the speed of change of each external factor, depending on the related factors acting on it. The results of the evaluation of crane failures under the proposed methodology do not contradict the studies of other authors and allow to assess the intensity of mutual influence of factors on each other. The proposed methodology may be recommended to assess the impact of factors of different nature in many areas of knowledge and science, such as riskology, reliability theory, etc.

This study examines the safety issues associated with the operation of elevator equipment, the causes of accidents during accidents, and suggests ways to reduce the severity of their consequences. A prerequisite for applying a risk-based approach in control and supervisory activities is the collection, systematization and analysis of information on the state of technical devices in order to assess the risk of incidents on them to ensure safe operation and reduce the administrative burden associated with inspections at facilities where the risk is minimal. The aim of the study is to develop ways to reduce the risk of accidents with personal injury or death at elevator structures and the severity of their consequences. The study used statistical data on the number of accidents and injuries during accidents on elevators of the Committee for Analytics and Statistics of the National Elevator Union. The analysis of accidents on elevators with the injury to life or health of victims. The causes of injuries and deaths were identified and systematized. Ways are developed to increase the safety of elevators during their operation and maintenance and to reduce the severity of the consequences of accidents.

The analysis of the spatial organization of the regional land use system is included in the list of the most important management tasks to ensure sustainable eco-logical-socio-economic development of territories. This task is valid for all levels of organization of the relationship between nature and society. The article is devoted to the actual problem of analyzing the territorial differentiation of the agricultural potential of the Re-public of Mordovia. This analysis is carried out at the level of municipal districts of the region. It is a key indicator of the effectiveness of agricultural development of the region’s landscapes. The authors used data from official statistics, regional agrochemical surveys, in-formation from state land accounting and statistical reporting on state land supervision, databases and electronic maps of the regional geographical information system «Mordovia». The article estimates of the agricultural potential of the municipal districts of the Republic of Mordovia based on the calculation of integral indices. All private indicators are combined into the indices «Potential of soil fertility», «Efficiency of agricultural land use» and «Intensification of agricultural land use». The authors revealed the dependence of the integral and particular parameters of agricultural land use efficiency on various indicators based on correlation analysis. The results of the research shows that the effectiveness of agricultural land use depends on the soil fertility of arable land, the agricultural potential of the municipal districts of the Republic of Mordovia significantly depends on the differentiation of landscape conditions.