Scientific journal «Technical service of agriculture, forestry and transport systems»

Improving the braking efficiency of two-axle vehicles when performing emergency braking under operating conditions

2021-03-19T08:18:55+00:00

To substantiate the possibility of increasing the braking efficiency of two-axle vehicles during the operational period, the method of mathematical modeling of the movement of a two-axle motor vehicle, braked on roads with a transverse slope, taking into account the action of the components of the aerodynamic drag force, was used. It has been established that in the case of performing emergency braking with a two-axle vehicle, there is a potential for the implementation of a larger braking force on the rear axle at the initial moment of braking, which, as a result, will make it possible to realize a relatively greater efficiency.In addition, due to the projected growth in the intensity and speed of vehicles, as well as the throughput of highways, increased requirements are imposed on ensuring road safety. An increase in the intensity and speed of movement, in particular, of two-axle vehicles, both equipped and not equipped with electronic braking tracking systems, can be achieved through a number of measures, including ensuring the minimum allowable distance between individual vehicles moving in a single stream.

Theoretical studies were carried out on a mathematical model of a two-axle vehicle being braked at various initial speeds of movement, varying within the range of 60–100 km / h. It was found that, depending on the value of the initial braking speed, the change in the normal load on the rear axle wheels can reach 23–32% at the initial moment of emergency braking on dry asphalt concrete.

Analysis of the relative change in the normal loads on the axles of vehicles during emergency braking, taking into account operational factors, shows that the normal loads on the rear axle, obtained from the refined dependencies, differ from the normal loads on the same axle, determined by the classical method, which creates the preconditions for reinforcing the rear brakes of a vehicle in order to increase its braking efficiency. However, this should involve electronic devices that monitor the change in the normal load on the wheels of the vehicle.

Development of a methodology for checking the power measurement system on a roller stand of a mobile diagnostic station for cars

2021-03-19T08:19:01+00:00

The development of technical diagnostics of cars should be considered in direct connection with the development of the entire system of their technical operation. Currently, various diagnostic tools have been developed that are used in many industries and transport. Diagnostics of the technical condition of many vehicle units and systems should be considered as a special type of physical modeling, combining physical models with full-scale devices. Diagnostic stands should provide simulation of physical processes occurring in real road conditions. It is important to realistic simulation of the processes of interaction of vehicle elements with diagnostic equipment, taking into account the actually acting forces, which will improve the accuracy of vehicle diagnostics at the stand.

The article discusses the issues of modeling conditions for obtaining diagnostic information about complex objects. As an example, the authors consider checking the traction properties of cars on an inertial roller stand. Such equipment must have a loading device that can ensure the verification of the traction and economic properties of a passenger car. As an alternative to AC and DC electric machines, an axial piston type hydraulic pump motor can be used for the loading device of the roller stand.

For this type of drive, it is necessary to develop a method for determining the power at the wheels of a car. In parallel with typical methods for determining power using balancing devices, it is proposed to measure power for a specific model of the stand by the differential pressure in the hydraulic system.

In addition, the measuring system of the inertial stand must ensure: objectivity of the assessment of the measured parameters; the minimum time required to carry out diagnostic operations; stability of measurements; simplicity and accessibility for service personnel; required measurement accuracy.

For this, methods have been developed for the experimental study of the metrological characteristics (verification) of the power measurement channel and the pressure measurement channel in the stand hydraulic system.

The conclusions substantiated the possibility of using the developed methodology in the design or modernization of inertial roller stands for testing the traction properties of passenger cars.

System express diagnostics of quality fuels and lubricants

2021-03-19T08:19:08+00:00

Humidity of fuels and lubricants is one of the determining indicators of their quality. The presence of moisture in the material affects their physicochemical and electrical properties. Water is characterized by high dielectric constant and the ability to easily interact with other substances.

The development of a humidity control system for fuels and lubricants during the operation of the machine is an integral part of the information-measuring and control systems of modern mobile equipment, and in particular special purpose vehicles.

Capacitive humidity sensors are distributed structures and in measuring systems the measurement parameters are both capacitance and resistance and inductance. To implement a capacitive meter with a linear graded characteristic, it is taken into account that the measuring medium is with large variable active losses, which are oils and fuels of internal combustion engines. To compensate for the active losses, a circuit with a separate measurement of the reactive component of the impedance of the dielectric primary transducer based on the modulation of the parameters of the measuring resonant contour is used. The parameters of such a circuit are chosen so that when the modulation capacitor is disconnected, the full conductivity of the circuit had an inductive nature.

The quality of the transformation of the measuring circuit of the sensor is adopted by the differential sensitivity, which characterizes the ratio of the relative increments of the output (full conductivity) and input (reactive conductivity) parameters.

An automatic single-frequency meter with a capacitive sensor made in the form of electrodes scattered field electrodes covered with an insulation layer has been developed, in which the method of modulation of the parameters of the measuring resonant circuit is used. To verify the theoretical studies, a complete factorial experiment was performed at three levels with two factors - the humidity of the test medium and the frequency of the supply voltage of the measuring contour.

The efficiency of the measuring circuit of the capacitive transducer is maintained in the entire range of measurements, if the quality factor of the capacitive measuring transducer in the material is greater than one.

Мethods for milk disinfection in the technological process of producing hard cheese

2021-03-19T08:19:14+00:00

In this article an innovative module of milk production and processing on the basis of Sumy National Agrarian University is presented and described in detail. The modes of milk pasteurization and installation by which this process is realized are investigated. The tubular pasteurizer is described and the substantiation of use of this pasteurizer in the innovative module of production and processing of milk is given. The process of making cheese from milk production to direct storage is described in detail.

Change of circuit current configuration during driving of a vehicle

2021-03-19T08:19:16+00:00

In the cases considered, a frequency shift of the maximum moment is observed both in the region of low and in the region of high revolutions, and the direction of displacement cannot be unambiguously tied to the type of engine or the manufacturer, although it is worth noting that for all the mentioned Volkswagen engines, the maxima are shifted to the right.

In most cases, the maximum torque during acceleration is reduced. On tested vehicles, the reduction does not go beyond 8%. This should be used when solving practical problems, for example, calculating the acceleration time of cars. In the low-frequency zone of some engines, the moment falls by 3–6 times in comparison with the nominal value obtained in steady-state modes. Presumably, the degree of this fall depends on the technical condition of the engine, for example, the deterioration of the cylinder-piston group.

The results obtained do not give reason to develop practical recommendations, but they clearly indicate the need for further study of the issue. More extensive and thorough research is needed, in particular, taking into account the age of the engine, in order to exclude the influence of the technical condition.

Experimental studies are presented in the form of experimental dependencies that reflect the torque curves of passenger car engines taken at steady loads during acceleration, depending on the speed range and the acceleration rate.

During acceleration in road conditions, the maximum value of the torque is obtained at a lower angular speed of rotation of 100–200 min ^{– 1}.

A technique has been developed for restoring the torque curve from the parameters of acceleration and coasting of the car, assuming that the static resistance during acceleration and coasting is the same, and the dynamic radius is equal to the radius of the rolling element.

Analysis of modern methods and devices for measuring soil hardness

2021-03-19T08:19:21+00:00

The article describes the influence of soil hardness on the development of crops from germination to crop formation. The main factors influencing the formation of an undesirable phenomenon in the soil, the so-called plow sole, are named. The analysis of modern existing methods and means of determination and measurement of soil hardness, both domestic and foreign manufacturers, starting from laboratory methods and ending with soil scanners, is presented.

The most common in our time hardness testers Goryachkin, Kaczynski, Golubev, Revyakin, Vysotsky, Hovhannisyan. In the research practice of Eastern European countries also used a large number of penetrometers (Kirice, Kunze, Florescu-Zellinger, Getko, Borish and others). New devices are also considered, which allow to carry out measurements in the mode of continuous registration simultaneously with tillage, to measure humidity and some other indicators, to accumulate results, to process them statistically and graphically. These are mass-produced American and Dutch hardness testers, as well as hardness testers from Slovakia and Sweden. Similar developments are underway in Ukraine (MM Surdu, VV Medvedev).

However, more complete information can be given by continuous field hardness measurement with soil density correlation, GPS overlay, and construction of electronic soil density maps.

The issue of soil hardness was and is relevant, because it depends on the formation of yields and, accordingly, the profit of farmers. Thus, there is an urgent task of improving methods and means of measuring soil hardness.

The question of developing a cheaper method, in contrast to soil scanners, to determine the plow sole, but no less effective than them.

The characteristic features of technological reliability of flax combine harvesters as their production capacity factors

2021-03-19T08:19:27+00:00

High quality fiber flax produce can be obtained under the conditions of harvesting the crop within short agrotechnical terms with respect to the crop maturity phases. Fiber flax seeds of the corresponding quality can be obtained when harvested in the yellow ripeness phase, the duration of which with respect to the fiber flax varietal peculiarities and weather conditions of the flax harvesting period fluctuates within the period of 5–10 days. In order to ensure harvesting within the time period specified, fiber flax combine harvester must possess the corresponding production capacity.

The research is aimed at improving the efficiency of using fiber flax combine harvesters by means of looking for the reserves of enhancing their production capacity. The technique of the experimental research is based on conducting stop-watch studies on the operation of flax combine harvester units (FCHU) included as components flax combine harvesters (FCH) ЛК-4Т. Besides combines, FCHU included 1.4 class tractors and 2ПТС-4М two-axle dump trailers. The FCHU crew consisted of a tractor driver, a combine-operator and a worker for smoothing flax masses coming from the combine to the trailer flatbed. The sheets of the stop-watch study there processed according to the well-known technique which serves as a component of farm machinery industrial tests. The components of the operation time balance of FCHU replacement were determined together with the assessment of the basic and total replacement time, and the FCHU production capacity per hour of the replacement time was determined through measuring the fiber flax area harvested by the unit, as well as through its relation to the total replacement time. The following indices were taken as the factors for the FCH technological reliability: the duration of the mean-time-between failures and the removal of these failures; the part of the duration of the technological failures within the structure of FCHU replacement time; the partial coefficient of using the replacement time which takes into account the FCHU idle time caused by removing the technological failures the coefficient of the FCH technological reliability and the number of the FCH technological failures per hour of the FCHU replacement time. The durations of the mean-time-between-failures and the removal of these failures were determined by means of processing stop-watch study sheets. Depending on the mean-time-between-failures. the production capacity of combine harvesters is described by the equation of a straight line with slope-intercept form; the duration of removing the technological failures and the part of this duration in the structure of the replacement time is described by descending hyperbolae; the partial coefficient of using replacement time which takes into account the idle time of harvesting units resulting from the removal of technological failures of harvesters and the coefficient of their technological reliability – by the equation of ascending hyperbolae; and the number of technological failures of harvesters per hour of replacement time – by the equation of descending exponent.

Mathematical modelling of the articulated wheeled machine motion with an elastic element in the connecting hinge

2021-03-19T08:19:31+00:00

The obtained dynamic model of the articulated wheeled tractor movement on irregularities takes into account the main design parameters that affect the position stability in the plane perpendicular to the support surface, as well as the characteristics of the support surface. To construct the equations of tractor sections motion, the Lagrange equation was used and, based on the design features of the articulated wheeled tractor, the number of assumptions were made to simplify the mathematical model. In this embodiment, the connecting joint of the tractor is a structure with an elastic element. The change in the angles of inclination of the generating irregularities of the surface under the articulated tractor sections wheels is given in the form of periodic functions. The angular velocities of the sections in the transverse plane perpendicular to the support surface are considered as a parameter of the dynamic position stability.

The presence of an elastic connection in the horizontal hinge affects the resistance against overturning and can be made in different designs. One such option is to use springs or spring that would redistribute the energy of the oscillations of the least stable front section to the more stable rear during the oscillations of the machine sections during the movement on the irregularities, while partially reducing this energy. In this way, the system will be more stable in terms of overturning and will ensure the absence of impact loads between the elements of the connecting hinge, increasing its reliability.

It is established that the presence of an elastic element in the horizontal hinge between the sections reduces the maximum values of the parameter of position stability – the angular velocities of the sections by 15-20%. This increases the dynamic stability of wheeled articulated machines.

The use of PTFE filter elements in the biotechnological production of antibiotic substance

2021-03-19T08:19:37+00:00

The paper shows the prospects of further research on the use of porous filters based on fluoroplastic in the production of antibiotic subtancies on the example of pyocyanin.

The analysis of research has revealed the urgency of the problem of antibiotic resistance of infectious agents, in this regard, there is a need to develop new types of antibiotics or improve existing ones.

Today, the main method of obtaining new antibiotics is biosynthesis, which is carried out by fermentation of the corresponding microorganism, and the final stage of any biotechnological production is the isolation of the target product from the nutrient medium and its purification. The initial stage of product isolation is filtration using filters of various designs. Among the large number of filter designs and filter elements of various compositions offered on the market, we focused on fluoroplastic filter elements.

The antimicrobial activity of P. aeruginosa culture liquid by two methods - the method of perpendicular strokes and two-fold dilutions studied. The research results showed that the antimicrobial activity slightly increased after filtration, which may be due to the concentration of cells and, accordingly, the release of a larger amount of antimicrobial substances by the cells of the P. aeruginosa microorganism.

Evaluation of accuracy and reliability of measuring fuel consumption

2021-03-19T08:19:41+00:00

The necessity of determining the actual value of fuel consumption during the operation of road vehicles is considered. The fuel consumption can be used to assess the complexity of operating conditions, the technical condition of the vehicle, adjust the frequency of technical impacts, and calculate the life of the machines. The cost of the transport operation and the intensity of environmental pollution depend on fuel consumption. Legislation limits fuel consumption, limits the accuracy of measurements and test conditions. The factors affecting the measurement of fuel consumption are con-sidered. Fuel consumption is determined by analytical and experimental methods. Actual fuel consumption is measured by the fuel level in the tank, according to the data from the controller of the engine control unit (k-line, CAN Buss), by measuring the flow of fuel entering the fuel line from the tank to the nozzles. In the latter case, indirect methods of measuring the flow are used: measuring the force effect of the flow, pressure drop, flow rate, time of filling the measured volume. The advantages and disadvantages of the main types of fuel flow meter are analyzed. Research was conducted on a piston fuel flow meter. After the measurement, it is necessary to perform the subsequent analog, analog-to-digital and numerical conversion. A flow meter calibration scheme has been developed. The estimation of the total error. The absolute and relative error values are obtained over the entire range of the measured indicator. The measurement results were processed by regression analysis. The coefficients of linear adjustment of the working volume of the fuel flow meter are obtained. The maximum error was estimated by the coefficient of determination. It is proposed to include in the program of the flowmeter control controller the procedure for correcting and accounting for errors. Conclusions and recommendations are developed, the main ways of further research are indicated.

Distance control of the technical condition of cars

2021-03-19T08:19:47+00:00

The data on the current state of motor transport in Ukraine and the disadvantages of existing maintenance and repair of cars in the technical operation of cars are given. The modern technology of remote estimation of the working condition of cars is developed, for which the information and communication model of the system of remote monitoring of the technical condition of the car is formed on the basis of the general approach to the research of the system "car - driver - operating conditions - infrastructure of operation of the car (transport and highways)". The model includes the interaction of components of monitoring components: a car with a driver and an on-board information system; Conditions of operation of the vehicle (road, transport, atmospheric and climatic conditions and culture of labor); transport infrastructure and road infrastructure). To implement the proposed technology an information program complex "IdenMonDiaOperСon" HNADU-16 "was developed, some of which are presented in the article.

Optimization of parameters of a two-drum combing harvester for harvesting oilseed flax

2021-03-19T08:19:50+00:00

The paper presents the results of experimental studies of substantiation of rational design and regime parameters of the harvester for harvesting oilseed flax by combing plants at the root. Processing of the results of mathematical modeling of the heap separation process in a combing type harvester with a curved shape of the casing taking into account the physical and mechanical properties of its components found that significant process factors are the following design parameters: speed of the reflector beater n1 the boundary L of the air grid of the casing and its width B.Experimental studies of the heap separation process in the harvester have established the dependences of the mass fraction of husk and stem particles from its area δ_h, the proportion of seeds and seed boxes δh and power P consumed on the speed of the reflector beater n₁ and the combing drum n₂, air position grid L and its width B. The most significant design and mode parameters of the combing type harvester for harvesting oilseed flax are highlighted: speed of rotation of the beater-reflector n₁ = 892 rpm, frequency of rotation of the combing drum n₂ = 652 rpm. , the position of the air grid L = 0,62 m and its width B = 0,56 m. The mass fraction of waste husk and stem particles is δ_h = 47,5%, the share of losses of seeds and boxes with seeds from the harvester, respectively, δ_h = 2,1%, and the power consumed to perform the process, P = 2,7 kW. Statistical analysis showed that the correlation coefficient between theoretical and experimental data is 0,88-0,95, the relative error of the optimal values is 4,6%. Visual and statistical comparison of theoretical and experimental data confirmed the adequacy of mathematical models developed as a result of theoretical research.

According to the results of experimental studies, it can be argued that their use for engineering calculations in the creation of new technical means for harvesting crops by combing plants at the root.

Study of the influence of the precision seeding system "Precision planting Delta Force" on the quality indicators of sowing and crop yield

2021-03-19T08:19:56+00:00

When choosing the type of seeding machines and their parameters, a whole range of factors should be taken into account, in particular, the seeding depth, soil type, moisture, the presence of plant residues, variety characteristics, etc., and also the heterogeneity of soil conditions within the same field should be taken into account.

The analysis of experimental data made it possible to determine the optimal parameters of the speed of the seeding unit at which it is possible to carry out the technological process of sowing sunflower and corn for grain with the provision of maximum values of quality indicators.

During the operation of the sowing units, the uniformity of the sowing depth of seeds at three different speeds with and without the Delta Force system was investigated. A John Deere 24 Row Planter precision planter was used for seeding. The measurement of indicators was carried out at operating speeds of 6 - 7 km/h, 8 - 9 km/h. and 9 - 12 km/h.

So we have determined that the most optimal range of operating speeds of the seeding unit is 8 - 9 km/h. When using the Delta Force system, it is possible to increase the values of the quality indicators of the unit's operation.

Comparison of the yield in the studied plots showed that the best results were obtained in the plot where the sowing was carried out using the Delta Force system. Taking into account that the climatic conditions, moisture and nutrient supply in both plots for each crop were the same, it can be concluded that it was the better sowing of sunflower and corn using the Delta Force system that made it possible to achieve higher yields.

Features of grinding and mechanical activation of mixtures of different-strength charge materials for wear-resistant surfacing

2021-03-19T08:20:01+00:00

Based on the analysis of physical and chemical phenomena that occur during mechanical grinding and mechanical activation of powder materials, a technology for synthesizing a modifying material using the SHS process and the process of surfacing wear-resistant coatings based on self-fluxing materials has been developed. An algorithm for estimating the degree of grinding of powder materials is proposed.

Еnergy-saving technologies of environmentally safe restoration and simultaneous strengthening of seating bearing for agricultural machines

2021-03-19T08:20:03+00:00

The paper presents the results of studies of various methods of restoring seats for rolling bearings (RB). The analysis made it possible to single out, as the most promising, the method of electrospark alloying (ESA) and deposition of metal-polymer materials (MPM) from all the considered methods. The combination of these technologies (ESA + application of MPM) made it possible to recommend for practical application a range of technological processes that allow using less energy-consuming and environmentally friendly technologies to restore RB seats.

In order to determine the most promising and environmentally friendly technology for restoring and strengthening the seating surfaces for the RB, comparative comparative tests were carried out on an SMTs-2 friction machine according to the disk-flat sample scheme, which served as a counterbody. A rectangular specimen made of VK8 hard alloy with a working surface roughness Ra = 1.6 μm was used as a counterbody.

As a result of studies of the wear resistance of coatings of samples made of steel 12Kh18N10T, it was found that the relative wear of uncoated specimens was 6.3; 4.7; 2.6 and 2.5 times higher than for specimens with coatings formed in the sequence: cementation by the ESA method (CEIL) → ESA Al → ESA T15K6 → MPM application; EILT15K6 → application of MMM reinforced with VK6 hard alloy; EILT15K6 → wire-reinforced MPM and EILT15K6 → MMM application.

Analysis of the laws of distribution of elements resources in the investigation of reliability of the press-granulator

2021-03-19T08:20:07+00:00

In the conditions of mechanization and automation of agricultural production the importance of indicators of reliability and durability in the overall assessment of the quality of machinery increases. In the meantime, the task of ensuring the reliability of the machines becomes more difficult due to the continuous increase in the power intensity of the parts and components as a result of increased operating speeds, increased loading during the universalization of the machines and many other factors associated with the progress of agricultural machinery. The peculiarity of the functional purpose and operation of the means of mechanization in animal husbandry is to ensure the continuity of biotechnical communication: operator - machine - animal - environment. This is possible only under the condition of the constant maintenance of the specified facilities in working condition, under which the coefficient of readiness of each unit should be at the level of 0.95 ... 0.98. There are several dozen distributions in the theory of reliability that can be used to describe experimental failure data. Considering different models of failures, a number of distributions are distinguished: normal, logarithmic normal, Weibull, gamma and exponential, which are the basis for the construction of models of durability of non-restored livestock products, replaced in case of failure of spare parts. These distributions cover, respectively, gradual, wear-out, fatigue and sudden failures of mechanical systems, complex systems that have undergone a period of service, as well as systems that are operated under severe conditions under the influence of mechanical and climatic loads. Characteristic of a normal distribution is that the failure rate starts at 0 and increases with time. This means that the failure flow is not stationary and there is an aging element. In the region of small values of t the aging of the elements does not significantly affect the reliability, so the probability of trouble-free operation of the product decreases slightly. After prolonged operation of the system, the failure of which elements have a normal distribution, its reliability rapidly decreases, so the probability of trouble-free operation decreases. Normal distribution is used for the gradual change of parameters, or in cases where the proportion of sudden failures is very small, that is, for products operating in favorable operating conditions. It is specific to describing progressive failures. The Weibull distribution corresponds to the situation of the weakest link in a set (a system consisting of a group of elements), and is also a flexible enough function to equalize various failure statistics well, which can be a model of failure of mechanical objects. Exponential distribution occurs in cases where the products are complex and the number of failures of different elements of the products with different intensity is possible. It has maximum density at the moment of switching on, ie it corresponds to low technology and quality of manufacture and assembly, excludes technological elaboration and finishing.

Principles of construction and functioning of a cyber-physical system of technical service of motor transport and mobile agricultural managers

2021-03-19T08:20:14+00:00

The results of research in the field of organizational behavior and team management in cyber-physical systems of technical service have shown that self-organizing teams are the most effective in the group behavior of resources.

The paper presents a multi-level self-organization of resources of a cyber-physical system of technical service based on a situational-oriented approach. The approach is based on the concept of the organizational behavior of the upper-level resources and ensuring their accounting in the self-organization of the lower-level resources. A schematic representation of the principles of construction and functioning of the cyber-physical system of technical service is given. It has been found that access to information about the resources of the cyber-physical system of the technical service is provided by using the technology of intelligent spaces.

The implementation of the situational-oriented approach is carried out on the example of a scenario for the provision of services in the maintenance of motor transport and mobile agricultural machinery with the participation of physical devices controlled by resource managers and planning resources responsible for generating the direction of the behavior of control resources. The concept of a structure-oriented approach is depicted in the form of levels of self-organization of resources in accordance with situations in the cyber-physical system of technical service. Self-organization at all levels of generation of situations of behavior of groups of resources, as well as internal-level self-organization are considered.

It is noted that the technology of intelligent space is built on the open platform Smart-M3 and its structure is presented. The general structure of the platform contains three groups of devices with information agents, a semantic information broker and physical storage of information. The platform itself is based on the concept of the Semantic Web. It is shown that the exchange of information between space participants is based on the Hyper Text Transfer Protocol standard using the resource identifier. The standard is based on client-server technology.

Analysis of the status of the dendroflora of the Volyn region

2021-03-19T08:20:20+00:00

The analysis of the current state of dendroflora of the Volyn region. The ecological and biological problems of green spaces in the conditions of urbanization are studied. The negative influence of urbogenic factors on woody plants is given. Urbanization is considered as an objective historical process of increasing the role of cities in the development of civilization with the simultaneous transformation of the natural environment, or rather, the environment of human existence - the creator of such a phenomenon as a city.

The level of atmospheric air pollution in the Volyn region, as one of the vital elements of the environment, which any change in the composition and properties of which negatively affects the health of people, animals, the state of the vegetation cover and the ecosystem as a whole, is analyzed. Ecological and biological problems of woody plants under various environmental growth conditions are presented. Polluted air constitutes both a direct negative threat to health and causes a slow destruction of various life support systems of the body. Very dangerous for humans are nitrogen compounds - nitrites and nitrates, which enter the air with the exhaust gases of automobiles and when making mineral fertilizers. Some of them are initial products for the synthesis of carcinogens. Polluted air significantly reduces immunity, negatively affects the respiratory system, causing respiratory diseases, catarrh of the upper respiratory tract, laryngitis, laryngotracheitis, pharyngitis, bronchitis, pneumonia, which today are quite common diseases of Volyn.

The consequences of anthropogenic impact on phenorhythmics and vitality of green spaces are considered. As a result of phenological observations, it was found that the main phenophases in woody plants within the city begin earlier and pass at a faster pace than in the suburban area. Therefore, the statement about the displacement of vegetative, metabolic processes and premature aging in trees and shrubs under the influence of urban environmental conditions is true.

The problems of increasing the vitality of the dendroflora of Volhynia were studied with the aim of preserving the existing biological and landscape diversity and creating new highly decorative plantations resistant to urban conditions for future generations.

The main task today is a comprehensive study of the state of Volyn dendroflora with the aim of preserving the existing green zones of cities, replenishing their range with new species resistant to the urban environment, followed by the expansion of their borders and the need for urgent creation of new green zones for general use.

The objects of the Volyn Nature Reserve Fund need not only creation and protection, but also care, restoration, reconstruction, restoration in order to preserve existing and create new highly decorative, sustainable plantings for future generations, which is a necessary condition in a modern urbanized environment.

Analysis of the improvement of the working body of the cable-layer during trenchless cable laying

2021-03-19T08:20:27+00:00

The article considers the design of the working body of the cable-layer when laying the cable in a trenchless way. The analysis on improvement of a working body of the cable-layer and the main advantages of trenchless laying of cables is carried out.

Trenchless cable laying in the ground is an effective technology that allows not to destroy the top layer of soil during underground works. Due to this, the need to block roads, disrupt the integrity of existing communications, destroy plantations disappears.

Trenchless cable technology allows not only to reduce material costs, but also to reduce the time of work. The length of the cable will depend on factors such as obstacles in the form of roads, highways, construction sites. The task of trenchless laying is: laying of water supply, sewerage, gas pipelines; laying of power supply cables, telephone and fiber-optic cable communication and alarm lines; replacement of worn-out communications with new ones; laying of the sewerage of any kind.

The article also covers the analysis of the improvement of the design of cable-laying with active earthmoving working bodies (ZRO), the principle of which is based on the trenchless method, which also have limited working speed and relative working speed, design complexity and low operational reliability.

The analysis of domestic and foreign constructions of trenchless pavers showed that in the practice of construction of underground communications more than 60 models of machines with various earthmoving working bodies are used in the shape of the working surface, which differently affect the soil environment.

According to previous studies, the most promising are trenchless trailed cable-laying with passive earthmoving working bodies. However, despite these advantages, trenchless construction has not yet become widespread. This is due to the fact that the traditional working bodies of trenchless pavers work on the principle of cutting and pressing the soil into the walls of the cut slit.

Application of composite electrolytic coatings to increase warning resistance of working bodies of grinding machines

2021-03-19T08:20:33+00:00

The article presents the results of research on the influence of composite electrolytic coatings (CEP) on the prospects of increasing the abrasive wear resistance of the working bodies of tillage machines: cultivator legs, disc harrows, plowshares.In this work, the influence of SiC (silicon carbide) filler particle sizes and their volume content in the nickel matrix on the tribological characteristics of QES applied to steel 45 samples was investigated.The formation of CEP with Ni-SiCano and Ni-SiC5, as well as with inclusions of amorphous boron was performed on a vertical cathode with continuous stirring of the suspension on our developed installation. The formation of CEP with SiC28, SiC50, SiC100 particles with the addition of amorphous boron powders was performed on a horizontal cathode. The change in the content of particles in the matrix was regulated by changing the ratio and (mixing time / sedimentation time) and changing the concentration of SiC and B particles in the electrolyte.CEP with inclusions of fractions 28/20 and 50/40 μm, which have the lowest wear at all loads, have the highest wear resistance among the given coatings. The filler content in such coatings is, respectively, 24 and 28 vol.%. At the same time coatings with inclusions of fraction of 28/20 microns have a little less wear. The weight wear of such samples is an order of magnitude less than for coatings with smaller and larger particles. Compared to galvanic nickel, such coatings have a reduction of wear of 12, 9 and 5 times at loads of 20, 40, 60 N, respectively.Analysis of the test results showed that the coefficient of friction is significantly affected by the friction load and the particle size of the filler SiC and there is a clear pattern that with increasing load such as the coefficient of friction decreases. Regarding the influence of the particle size of KEP filler on the coefficient of friction f, it can be noted that the coefficient of friction decreases with increasing particle size and for the range of particle sizes of filler 40… 60 μm the coefficient of friction is minimal. For coatings with large filler particles (fraction 100/80) the coefficient of friction is higher.The highest wear resistance of coatings with inclusions of size 28… 50 μm may be due to the distribution of the load they receive. The load on the solid inclusions is equal to the actual contact pressure when their size is smaller or commensurate with the size of a single contact spot (2-10 μm). For compositions with optimal particle sizes (28 μm) there are no processes of setting, abrasive and brittle fracture and there is a normal mechanical-oxidative wear process.Thus, tribological studies show the prospects and effectiveness of CEP to increase the wear resistance of the working bodies of tillage machines.

Conceptual principles of integrated quality customer service management of logistics provider

2021-03-19T08:20:40+00:00

The essence of integrated management was investigated in the article, own definition of the concept of integrated customer service management of the logistics provider was given, the structure of the customer service quality management system was proposed, as well as an improved logistic provider quality customer service Gap-model.

The modern market requires continuous improvement of the quality of products and services as a major factor in increasing competitiveness, including logistics providers. To solve this problem, you need to have integrated customer service quality management systems that take into account the requirements of international standards and all participants in this process. Studies have shown that the most appropriate way to improve the efficiency of customer service management of a logistics provider in the face of growing competition is to create an integrated management system.

As studies have shown, integrated management systems are built on the basis of applying a system and process approaches to enterprise management, allowing you to connect the various processes and activities of the enterprise into a single whole.

The activities of any organization are associated with risks that determine the main losses. As noted, the goal of creating an integrated management system is overall optimal risk management, which reduces the material and organizational resources needed by the enterprise.

Integrated customer service management of a logistics provider is, above all, the art of compromise, in which decisions are made based on a common goal, taking into account the interests of all participants in the logistics process. In this case, the main difficulties arise in a situation where neighboring units use different principles of organization and planning of operations in supply chains.

To improve the quality of customer service, from now on it becomes impossible to consider the activities of only a logistics provider in isolation. The increase in the number of market entities involved in the customer service process makes it difficult to manage this process, which should be organized in accordance with the concept of optimizing total costs and quality management at all stages of customer service. Integrated quality management of customer service of a logistics provider should provide for the harmonization of quality of services throughout the service chain. Various companies, business partners involved in this chain, should realize that they are links in one process and have a common goal - the maximum satisfaction of customer needs.

Integrated management of customer service quality of the logistics provider will minimize the total cost of resources of both the logistics provider and its business partners, provided that the necessary level of customer service quality is provided.

Evaluation of the effectiveness of fullerene compositions in hydrostatic drives of agricultural machines

2021-03-19T08:20:47+00:00

The analysis of application of fullerenes and fullerene additives to working liquids of hydrostatic drives is given HST-90 agricultural machinery. It is shown that the use of fullerene compositions in hydraulic oils of hydrostatic drives of agricultural machines is a promising direction and will reduce friction losses in tribosystem HST, which will lead to fuel savings, while reducing the rate of wear of materials of tribosystems and increase resource.

The purpose of this work is an experimental study of the effectiveness of fullerene compositions in hydraulic oils of hydrostatic drives and the degree of their impact on the specific fuel consumption of the drive motor. The mass of the fullerene composition 100 gram per kilogram of hydraulic oil. The composition of the fullerene composition - 0,75 gram fullerenes and 99,25 gram vegetable rapeseed oil. The total weight of the fullerene composition 100 gram was introduced into 1000 gram of base hydraulic oil MGE-46V, (10% masses).

Friction losses in tribosystems HST-90 evaluated by the magnitude of the power of the drive motor on the test bench KI-4815M. The number of the same type of HST sets, which give the necessary reliability and reproducibility of the results and is sufficient for bench tests and give the necessary reliability and reproducibility of the results for confidence q=0,90, relative error ε=0,05 and coefficient of variation υ =0,15, is equal to 12.

Tests of the HST set on the stand were performed in two stages. At the first stage of testing, the working fluid MGE-46V was used according to the technical conditions. In the second stage of the tests used working fluid MGE-46V with the addition of fullerene composition.

Experimentally obtained values of reducing the power of the electric motor on the drive HST-90 during the tests on the stand. It is established that when using a fullerene composition in the working fluid MGE-46V, the power of the electric motor to drive HST is reduced by 17,2…17,6%.

The sample size of the supply coefficients Ψ and efficiency factor η for pumps and motors has been tested for compliance with the normal distribution law. The obtained calculated values allow us to conclude that the sampling results correspond to the normal distribution law. Homogeneity and reproducibility of test results were evaluated by the value of the Cochren test, which allowed to establish – the results obtained are homogeneous and reproducible.

The use of fullerene composition in the working fluid will reduce fuel consumption by diesel agricultural machinery. On the example of a combine harvester, which uses HST-90, the reduction of diesel fuel consumption from the use of fullerene composition is calculated. When the combine harvester operates 300 operating hours per season, fuel savings will be 735 kg per one car.

The process of trimming and raising the soil by the working bodies of the soil treatment and separation installation

2021-03-19T08:20:53+00:00

The subject of the research is the process of functioning of disk working bodies and a ploughshare of the soil-cultivating loosening-separating installation, which carries out lifting and separation of the soil. When moving the ploughshare at shallow depths (0.03 ... 0.12 m), the movement of the soil along it is complicated by the formation of a soil roll, which is formed in front of the ploughshare. The soil is loosened and scattered to the sides, not providing the necessary support required to move it to the loosening-separating device. Passive rotating disks are installed on both sides of the ploughshare so that the soil does not clump and scatter to the sides. The object of the study are the disk elements of the lifting and trimming device, which can significantly increase the efficiency of the technological process of soil movement on the ploughshare while reducing the specific energy consumption of the process. The initial information to substantiate the study was obtained by analyzing the literature. It is determined that increasing the radius of parallel freely rotating flat disks from 0.175 to 0.270 m leads to an increase in the thickness of the soil layer on the ploughshare by no more than 17%. With increasing kinematic parameter of rotation of the disks from 0 to 0.6 soil compaction on the ploughshare decreases by 2.73 times, from 0.6 to 1.0 - by 1.25 times and from 1.0 to 1.2 - by 1, 04 times. It is established that increasing the angle of the ploughshare initially leads to a decrease in the soil level on it and reaches a minimum at an angle close to 25 °. With a further increase in the angle, the soil level on the ploughshare increases.

It has been experimentally proved that the greatest influence on the limiting distance between the disks at which the lifting of the soil layer by the ploughshare is carried out without jamming is the soil moisture. The relevance lies in the fact that the simultaneous use of passive disk working bodies together with a ploughshare allows to improve the methods of pre-sowing tillage to improve its agronomic qualities.

Questions of localization of faults in the fuel supply system with direct injection

2021-03-19T08:20:57+00:00

Direct injection system - (Gasoline Direct Injection (GDI) - a fuel supply system for gasoline internal combustion engines, in which the nozzles are located in the cylinder head and fuel is injected directly into the cylinders.Direct injection (DI) system has become widespread due to significant fuel savings , which reaches up to 20% [1]. The popularity of the system, together with the fact that its design differs in many respects from the device of its predecessors, determined the demand of the automotive public for the availability of systems diagnostics services and localizing its faults. Many variants of the system of various environmental standards, manufacturers and years of manufacture are known to date. The article sets the task, using a specific system model as an example, to show the sequence of localization steps and the required amount of preliminary information for the development and compilation of a matrix for determining faulty components of the high pressure circuit.

The mass spread of power supply systems with control units provides for wide access to maintenance and repair services, in particular, to diagnostics services. For this, OBD-2 scanners, universal and focused on specific car brands, as well as universal means of measuring physical quantities (manometers, ohmmeters, ammeters, etc.) can be involved. An important role here is played by observing the features of the engine's behavior, such as twitching, sudden loss of power, sudden stop, etc.

Features of the fuel supply system with control unit: self-diagnostics, two circuits - low pressure and high pressure. In addition, each circuits has its own closed- circuits pressure control circuits that delivers fuel on demand. This function is also supported by the control valve in the high pressure fuel pump (injection pump), which has a normal open position. The features of the system structure were used in the development of algorithms and a matrix for diagnostics. In addition, the results of observations of the behavior of the car, cause-and-effect relationships in the presence of malfunctions, and the opening of feedbacks in the circuits were taken into account. During the development of rational diagnostic algorithms, various criteria for choosing a sequence of operations are usually used: a probabilistic criterion, criteria for minimizing the complexity of the verification operation. The complex criterion was used in this case - the ratio of the probabilistic characteristics and the characteristics of labor intensity, the use of which, due to the bilateral action, can increase the efficiency of diagnostics. Preference was given to maximizing the ratio of the failure rate parameter to the labor intensity of component replacement, bearing in mind that manufacturers of cars and their electrical and electronic components, if a malfunction is suspected, recommend replacement for the time of diagnostics.

Determination of indicators of the level of technical operation and their impact on the reliability of equipment

2021-03-19T08:21:05+00:00

The problem of choice of factors of influence and estimation of their influence on indicators of technical operation and first of all on operational reliability of equipment is opened in the work. The effectiveness of the management of the process of formation of operational reliability requires the involvement of designers, scientists, workers in the field of operation and repair of equipment, while the main features of this process are dynamism and adaptability. The paper presents that we can identify several main, generalized, factors that most significantly affect reliability. Such factors include, in particular, the quality of running in the tractor, organization and quality of maintenance, quality of maintenance, storage and quality of fuels and lubricants, characteristics of tractor drivers, storage of tractors, security of farms, the level of organization of tractor use. Each of the main factors, in turn, is characterized by determining, individual, factors. For example, the organization and quality of maintenance depend on the completeness of the operations performed, the availability of equipment and tools, the frequency and location of maintenance, the composition of the performers. The value of each determining factor is quantified using conditional numerical values that reflect the physical essence of this factor. The weight of the influence of certain factors on the level of technical operation should be taken into account. Solving these problems by rigorous mathematical methods is very difficult, because the extraordinary variety of a significant number of factors and their combinations makes it almost impossible to collect the necessary information and make the appropriate very complex calculations. A more rational way to quantify factors is the generalized Harrington desirability function. At the heart of its construction is the idea of transforming the natural values of individual factors into a dimensionless scale of desirability or preference. Having built a model for assessing the state of determining factors on the level of technical operation of tractors on the basis of regression analysis, we found that the range of values of factors is: organization and quality of repair – 0,800...0,855; characteristic of the tractor driver – 0,808...0,897; quality of equipment storage – 0,705...0,882; characteristics of the tractor fleet – 0,735...0,872. Thus, the increase in the level of technical operation is carried out by bringing the levels of generalized factors to the given values. Establishing the sequence of increasing generalized factors is achieved by arranging the factors in descending order of their weight.

Improvement of quality indicators of cast iron rolling rolls applicable to the production of balls

2021-03-19T08:21:12+00:00

It is stated that rolling rolls of different materials are used for the production of grinding balls. The main indicators of the quality of these tools are the level of mechanical properties: hardness, toughness, tensile strength, tensile strength, thermal endurance. Operating conditions of rolling rolls are characterized by cyclical effects of temperature and specific pressures. Therefore, the directions of research of ways to improve such an indicator of the quality of rolling rolls as thermal endurance are especially important. It is noted that the rolls of mills in the production of bullets of large diameter (80-120mm) have a much lower load on the gauges than in the rolling of bullets of small diameter, so for their production it is advisable to use high-strength cast iron with spherical graphite. Analysis of the use of cast iron rolls showed that their quality indicators are significantly affected by the shape and size of graphite inclusions. To increase the level of mechanical properties and thermal endurance of cast iron by obtaining the "correct" shape of graphite of the required size, studies were performed on the modification of the melt of the rolls of SSHNM-46. During the research it was found that the ratio of barium and magnesium in the modifier in the range of ~ 1.4: 2.0 determines the highest level of plasticity due to the optimal size of graphite inclusions. Increasing the recommended ratio of Ba: Mg over 2.3 leads to an increase in the size of graphite inclusions (more than Graz 360) and at the same time to a deterioration of their shape (up to Gf 9). Increasing the size of graphite inclusions leads to a decrease (by 23 ... 28%) of mechanical properties. Based on the results of research, it is determined that the highest quality indicators - the level of mechanical properties and thermal endurance has cast iron containing 3.8% C, 1.84% Si, 0.30% Mn, 2.00% Ni; up to 0.10% Cr, 0.30% Mo, up to 0.04% Mg, 2.5% Cu; up to 0.04% Ce; up to 0.08% Ba. The thermal endurance of such cast iron is 3120 cycles before failure (20 ↔600 ° C). Rolls from the offered pig-iron, having higher level of properties, are capable to provide decrease in their specific expense in 1.2 - 1, 5 times and will promote reduction of downtimes of conditions on transshipments.

" Estimation of efficiency of automobile transport systems on the basis of mathematical methods

2021-03-19T08:21:16+00:00

Logical-probabilistic methods of Boolean algebra allow not only to quantify the reliability of complex transport systems, but also to determine the role of individual elements of the structural scheme of reliability and their combinations in ensuring the reliability of road transport systems.

In the absence of information on the reliability of the elements, their impact on the reliability of the entire system is assessed using the concept of the weight of the elements in the structural diagram of the reliability of the transport system. The weight of the element characterizes the relative number of such critical working states of transport systems, in which the failure of the element leads to the failure of the system and vice versa, the restoration of the element leads to the restoration of the transport system of all its states.

It is shown how the elements of Boolean algebra can be used in assessing the reliability of the chains of elements of transport systems in general and how with the help of Boolean algebra concepts logical functions can be reduced to an orthogonal disjunctive normal form. An equivalent form of a logical function is given through elementary conjunctions of different ranks. It is shown how it is possible to use transformation of logical function in calculation of probabilities of faultless work of transport system. Logical functions are represented through elementary conjunctions as well as in matrix form. Transformations of a logical function are considered on the example of a transport system consisting of eight elements. The formula for calculating the probability of failure-free operation of such a transport system is obtained.

Concepts such as the assessment of the weight, significance and contribution of individual elements of the structural scheme of reliability in the reliability of the road transport system or its chain are clarified. The general formulas of probability of trouble-free operation (n-elements) for the transport system are obtained and their implementation is considered on the example of a structural scheme of five elements. The content of the probability of a monotonic logistic function and its derivative is considered. The formulas for calculating these characteristics for the system element are obtained. There are five important consequences of their relationship, taking into account the working and inoperable element in the structural scheme of reliability of transport systems.

Key words: estimation, working capacity, reliability, automobile transport system, elements, structural scheme, mathematical methods.

Justification of economic performance and efficiency of restorative surface of details compositional materials

2021-03-19T08:21:24+00:00

Based on the analysis of scientific and technical literature, the work substantiates the economic feasibility of restoring machine parts. The calculation of the economic efficiency of the use of the created composite material and the technology of its electric arc surfacing on the example of the restoration of the axle of the balance beam of the rear suspension of the KamAZ automobile is presented. The economic effect was assessed at the cost of restoration and from changes in the resource of the part.

Keywords: resource, composite material, surfacing, oxides, wear, economic efficiency.