Application of computer systems for modeling dynamic processes of lifting machines

The main task of mechanical engineering is to organize the production of a range of machines to meet the needs of all industries. These are power, transport, lifting and transport units, agricultural machinery, construction industry, etc. Among them, one can single out devices in which the relative movement of their parts is assigned, that is, kinematic pairs are included in the calculation models. The real operating conditions of machines are varied, but most often they are associated with periodic starts-stops, which determines the relevance of the study of unsteady modes. The analysis of the operation of such models becomes more complicated. For successful design results, mathematical modeling of individual processes in mechanisms is carried out. One of the first calculations is dynamic. Modern, available CAD / CAE systems for modeling and analysis provide automation capabilities, building more realistic design models. The paper discusses the approbation of the use of CAD for modeling the dynamics of a jib crane with a set of four units: platform, boom, sleeve and rod. The developed model is combined: the platform and the sleeve correspond to the kinetostatic model, and the boom and rod are elastic. The crane is designed to perform lifting operations in a vertical plane, with the possibility of relative movement in 3 rotational and one translational kinematic pairs. The performed calculations of the static, modal and dynamic analyzes of the links of the mechanism confirm the adequacy of their models. Among them is the task of instantaneous load application, which is typical for the "lifting and picking" operating mode of crane lifting mechanisms. The deformation of the entire structure in one of the boom positions is also considered. The determination of the reaction forces in the hydraulic cylinder provides important information for the selection of the power unit.

Energy efficiency of multivariate cultivation techniques in pasture forage production

Исследования по определению энергетической эффективности пастбищных систем со злаковыми и бобово-злаковыми травостоями проведены в Федеральном научном центре кормопроизводства и агроэкологии им. В. Р. Вильямса. В статье приведены результаты агроэнергетической оценки многовариантных пастбищных систем со злаковыми травостоями, созданными в 1946 году. Даны количественные показатели по сбору обменной энергии, совокупным затратам на её производство, окупаемости затрат в зависимости от системы ведения пастбищ. Изучена эффективность совокупных затрат в виде овеществлённого труда (на семена, удобрения, сельскохозяйственные машины, средства огораживания загонов и прочее) и живого труда (работы трактористов, пастухов и строителей и др.). Обоснована высокая агроэнергетическая эффективность изучаемых пастбищных систем благодаря мобилизации в продукционный процесс природных факторов, долевое участие которых в структуре производства обменной энергии составило 69–84%. Природные факторы, участвующие в продукционном процессе луговых агроэкосистем, характеризуются большим разнообразием. Это не только использование солнечной энергии и азотфиксация бобовыми травами, но и долголетие травостоев, самовозобновление фитоценозов, дерновообразовательный процесс (повышение плодородия почвы), получение дешёвого корма и улучшение здоровья животных при летнем выпасе. Роль возобновляемых природных факторов выявлена на основе балансового метода, принятого в экономике (по разнице сбора обменной энергии и антропогенных затрат). Благодаря ведущей роли природных факторов в структуре произведённой продукции агроэнергетический коэффициент окупаемости совокупных затрат антропогенной энергии (АК) за счёт сбора обменной энергии достигал 3–6 раз в среднем за 45 лет. Разработанные в результате долголетних исследований многовариантные энергосберегающие пастбищные системы обосновывают возможность рекомендовать их производству с учётом применения различного уровня энергозатрат. Ключевые слова: культурные пастбища, системы ведения, долголетние травостои, сбор обменной энергии, совокупные антропогенные затраты, окупаемость затрат. The investigation was conducted at the Federal Williams Research Center of Fodder Production and Agroecology and was aimed at testing energy efficiency of gramineous and legume-gramineous swards. This article presents the results obtained on pasture ecosystems with gramineous planted in 1946. Exchange energy yield, total production costs and economic effectiveness were analyzed. Total production costs comprised costs for seeds, fertilizers, machinery, construction materials, labor, etc. Introduction of natural factors into the production process resulted in higher energy efficiency. Their share amounted to 69–84% in the final exchange energy yield. There are a lot of natural factors that affect grass productivity such as solar energy, nitrogen-fixation, sward longevity and regeneration, soil fertility, low-cost feed production, and livestock health. The value of natural factors was determined according to the balance method (by the difference between exchange energy yield and anthropogenic costs). Since environmental factors had a leading role in the production process, the return rate raised by 3–6 times for 45 years due to exchange energy increase. Therefore, pasture ecosystems developed can be recommended for a large-scale forage production.

Study of Tensile Strength Test of Oxi-Asetyline Welding with the Addition of Borax to St 37 Steel

The use of welding in industry today is very broad, including shipping, machinery, construction and others. The aim of this research was to study the welding results of two types of metal with different melting points, namely low carbon steel ST37 with brass filler and borax added during the welding process using OAW (Oxygent Acetyline Welding) welding. The specimen size is 170 mm long, 50 mm wide and 8 mm thick. As for the test method with the addition of borax, then look at the results of the number of porosity, weld defects and differences in tensile strength in each specimen by conducting penetrant liquid testing and tensile testing with ASTM E-8 standards. The results of the penetrant liquid test showed that welding ST 37 steel using borax as an additional material produced welding with the smallest porosity and even no defects at all compared to specimens without using borax. The results of the tensile test show that the addition of borax has a tensile strength value of 2000 kgf / mm². This value is greater than without the addition of borax.

To the issue of identifying some objects of operational protection by criminal police units of the National Police of Ukraine

The subject of the investigation are the operational maintenance objects of the machine-building complex and the recreational-tourism sphere by criminal police divisions. The research methodology includes the following methods: general and special legal: monographic method, method of analysis and synthesis, comparative legal method, classification method, statistical method, abstract-logical method. Scientific approaches to operating service definition are considered. An analysis of the machinery construction complex and the tourist and recreational field was carried out to achieve high standards of its operational service. As a practical dignified facility of the machinery construction complex and the tourist and recreational sphere were ordered in appropriate groups to identify those in need of operational maintenance. It is concluded that the regulations of the Ministry of the Interior and the National Police of Ukraine do not contain provisions that clearly define the content of the institution of operational services and its place in the system of operational and investigative units to combat crime.

Effects of an Impeller Rim and Radial Clearance on Energy Characteristics of an Axial Pump

The results of numerical and experimental research conducted in the Laboratory for Hydraulic Machinery Construction of Peter the Great St. Petersburg Polytechnic University are presented. The research is aimed at studying the effects of an impeller radial clearance and rim on the energy characteristic of low-pressure axial pumps of the specific speed ns≈600. It is shown that these design features of a flow duct have significant effects on stage parameters, and they have to be accounted for when verifying design and experimental characteristics of axial pumps.

Analysis of equipment for performance of riveted joint in machinery construction (Patent review)

Structures of technological equipment for performance of riveted joints of machine parts are considered. A description of the equipment designs is presented, the technical result of which is to improve the quality of produced riveted joints, reduce the labor intensity of the technological process, and improve working conditions.

Fraud Prevention in the Leasing Industry Using the Kohonen Self-Organising Maps

Background and Purpose: Data mining techniques are intensely used in various industries for the purpose of fraud prevention and detection. Research that focuses on the leasing industry is scarce, although frauds in the field of leasing occur rather often. First, we identify clusters of business clients in one leasing company by using the method of self-organising maps based on leasing contract attributes. Second, we compare clusters based on the presence of fraudulent clients, in order to develop fraudsters’ profiles.Methodology: For detecting characteristics of fraudulent clients, we use a client database containing leasing contract attributes of one Croatian leasing company. In order to develop profiles of fraudulent clients, we utilise a clustering procedure with the Kohonen Self-Organizing Maps supported by Viscovery SOMine software.Results: Five clusters were identified and labelled according to the modal values of attributes describing the leasing object and the industry in which the client operates: (i) New cars / Trade; (ii) Used trucks or tugboats / Other services; (iii) New machinery / Construction; (iv) New motors / Trade; and (v) New machinery and tractors / Agriculture.Conclusion: Self-organising maps have proved to be a useful methodology for developing profiles of fraudulent clients in leasing companies. Companies can use our results and make additional efforts in monitoring clients from the identified industries, buying specific leasing objects. In addition, companies can apply our methodology to their own databases, in order to develop fraudster profiles for their specific purposes, and implement fraud alert mechanisms in their client database.

Trends in the development of technical level of the specialized flax harvesting machinery

Production of domestic specialized flax harvesting machinery has almost completely stopped in Russia, and the technical level of available fleet machines is significantly concedes to foreign models in many indicators. The main indicators of the technical level have been predicted based on the analysis of the construction development of flax harvesting machine, main directions and achievements in agricultural machinery construction and related areas of equipment. Application of flax harvesting machine with this technical level will significantly improve energy efficiency in flax production.

Configuration and Maintenance Management of Highway Engineering Machinery and Equipment

Firstly, this paper analyzes the necessity of highway engineering construction machinery and equipment management, discusses the configuration management of highway engineering machinery and equipment, and then puts forward the problems existing in the management and maintenance of highway engineering machinery construction equipment. Finally, the management and maintenance measures of highway engineering machinery construction equipment are discussed in a targeted manner.

Development and calculation of a new constructive scheme of spiral potato heap cleaner

Purpose. Improvement of quality and productivity of potato peeling process by means of development and substantiation of new construction of spiral peeler taking into account reduction of losses and damages of potato tubers. Methods. Development of a new construction of a spiral cleaner is based on the application of basic principles of agricultural machinery construction, patent search and methods of calculation of basic construction parameters of the machine. Results. In the paper the authors developed a new construction of spiral potato peeler capable of active self-cleaning from sticky soil, effective removal of soil and plant impurities and qualitative cleaning of potato tubers with their minimal losses and damages. Presence of five wave-likely located working spirals has given the chance to expand considerably a working zone of separation of an arriving potato heap that promotes its better dispersal on a working surface of a cleaner, more intensive destruction of soil clods, and hence improvement of sifting of soil and vegetative impurity and reduction of clogging of working spirals that finally raises productivity and working capacity of a potato cleaner. The process of cleaning the tubers from soil and plant impurities is carried out due to the movement of the potato heap by means of the coils of the console fixed spiral springs rotating at a certain angular speed and the oscillatory movement of the springs themselves, arising due to the deflection of their longitudinal axes under the influence of the weight of the heap cleaner entering the working area. Soil and vegetable impurities are sieved through separating gaps and spiral coils, and potato tubers are transported by spiral coils towards the discharge conveyor. Conclusions 1. A new construction of the potato peeler has been developed, the main difference of which is five cantilever mounted cleaning spirals,arranged in waves at different heights, which allowed to expand the cleaning working area and improve the quality of cleaning potato tubers from soil impurities and plant residues. 2. The expediency of developing a new construction of the potato heap cleaner is confirmed by its efficient operation, high quality of cleaning of tubers from soil and plant impurities, ability of working bodies to self-clean from sticky soil, simplicity of construction and reliability in operation, increase of the cleaner's productivity. 3. Calculations of the required power for the drive of the new spiral cleaner have shown that it does not exceed 1.3 kW. 4. Preliminary calculations show that the use of the proposed spiral potato peeler cleaner will improve the quality of potato tubers cleaning from impurities by 15...20% in comparison with the triochspiral cleaner. Keywords: potato heap, tuber, impurities, purification spiral, coils, oscillatory motion, self-cleaning.