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Introduction. The key stages of sludge processing technology are the destruction of conglomerates into metal and non-metal components, as well as the grinding of component particles to obtain secondary raw materials of the required granulometric composition. The use of a rotating electromagnetic field for processing grinding sludge makes it possibleto exclude the application of various means of destruction and grinding, avoiding contact interaction of agglomerates and the walls of the working chamber. Thus, the material consumption of technical means is reduced, and the efficiency of the destruction process is increased. The study aimed at establishing the features and basic patterns of sludge waste processing in devices with a rotating electromagnetic field. Materials and Methods. For the research, grinding sludge was used, which was a collection of conglomerates of arbitrary shape, consisting of 80-85 % of metal chips. An induction method was applied based on establishing the connection of the EMF induced in an induction sensor and the magnetic induction of a rotating electromagnetic field. The influence of induction on the nature of interaction between sludge particles in a rotating electromagnetic field was evaluated by changing the relative EMF signal induced in an inductive sensor. Results. As a result of experimental studies conducted using the induction method, it has been found that the dynamic characteristics of sludge waste conglomerates depend on the induction of a rotating field to a certain value. With an increase in the size of sludge conglomerates, with the same size of ferromagnetic particles entering it, the magnitude of the magnetic field induction required for their destruction decreased. With a decrease in the particle size of conglomerates, the field induction required for the destruction of conglomerate bonds increased. An increase in the number of particles in the conglomerate reduced the value of induction. The degree of destruction of the conglomerate and the grinding of its ferromagnetic particles depended on the duration of the rotating electromagnetic field induction. Discussion and Conclusions. The proposed induction method makes it possible to investigate the influence of electromagnetic field parameters on the change in the state of the magnetic vibrating layer, as well as to evaluate the kinematic characteristics of ferromagnetic medium particles in the magnetic vibrating layer.

Introduction. To search for effective methods of finishing and stripping of long-length parts, it is advisable to create a rotary-screw process system of a pass-through type. Its main working element is a screw rotor, which is a combination of flat elements of various shapes and sizes, multidirectional with respect to the helical lines around the perimeter. The purpose of this study is to justify the intensity of the machining process in devices equipped with a screw rotor.Materials and Methods. Metal removal is accepted as the main parameter determining the intensity of the machining process in screw rotors. Within the framework of the presented study, processing was performed on an experimental rotary-screw installation. The processing medium consisted of molded abrasive pellets of the PT 10x10 brand. The research conditions were as follows: loading volume (without part) — 60 %; rotor speed — 50 rpm; processing time – 30, 60, 90 min; rotor axis tilt angles — 0о and 5о. The influence of treatment modes and conditions on the process intensity was considered on plate samples with dimensions of 80×10×1 mm made of aluminum alloy D16T. To determine metal removal, the samples were weighed on Ohaus AX223 analytical balance before and after processing.Results. The patterns of metal removal from samples at different processing times, the location of samples in the working area of a screw rotor with different angles of inclination, and its speed are presented.Discussion and Conclusions. The regularities established in the course of research indicate the efficiency of rotaryscrew process systems for solving problems on the finishing treatment of long-length parts. The main factors that control such processing in devices with a screw rotor and affect its intensity (and, as a consequence, the process performance) are the screw rotor speed, the shape of the perimeter, and the axis angle.

Goal. Finding ways to improve the quality of operation of the electrode wire feeder in terms of increasing the frequency of undistorted pulse feed with controlled characteristics, in particular its speed, as well as developing methods to simplify the adjustment of regulators of fast-acting electric drive to improve the results of the arc welding and surfacing process. Methodology. In the work, methods of analysis of existing technical solutions were used to increase the speed of operation of electric drives for a specific purpose with the choice of the most rational solution based on the use of the method of synthesis of a control system based on the concept of inverse problems of dynamics with subsequent computer simulation, confirming the adequacy of the applied method of synthesis of high-speed systems. Results. The authors considered the possibilities of increasing the speed of control systems for gearless computerized electric drives in a system with modern designs of valve electric drives for electrode wire feeding systems. A mathematical model of a rectifier motor has been developed with some assumptions that significantly influenced the simulation results. The new possibilities are based on the use of an original synthesis method based on the use of the concept of the inverse problem of dynamics with the subsequent study of the operation of the automatic control system for pulse wire feed, which was performed with aperiodic adjustment of the velocity contour by different methods. This approach made it possible to obtain the necessary laws of electric drive control without the traditional solution of the optimization problem. The developed control system for the electrode wire feed with pulsed motion algorithms provided the required linear movement of the wire at a pulse repetition rate of 100 Hz. The carried out computer simulation of the new control system confirmed the results of the study. It was found that an increase in the pulse time duration over 50 % of the pulse repetition period for given feed frequencies leads to an increase in the wire movement in the pulse, as well as to a decrease in the worked out frequency of the wire linear displacement feed. It was not possible to provide the required wire movement in the impulse feed mode for aperiodic adjustment of the speed loop with a P-controller for the same system parameters. Originality. The development was carried out for a specific application in the electrode wire feed systems of mechanized and automatic equipment for consumable electrode arc welding with obtaining certain algorithms of pulse motion. To effectively solve the complex problem of increasing the frequency of feed pulses with the provision of a displacement step, an original technique of the concept of inverse dynamic problems with confirmation of the result by mathematical modeling by practical results was used. Practical significance. The use of standard settings of the valve electric drive of mechanized and automatic welding equipment provides the frequency of undistorted electrode wire feed in the pulse mode of the feed mechanisms up to 50 Hz. New possibilities of settings made it possible to increase the frequency of wire feed, which makes it possible to raise the quality indicators of welded products - the formation of a welded joint, a decrease in electrode metal losses, an increase in the mechanical properties of a welded joint.

Introduction. The technological features of the processing crankshafts by the vibration shock method of surface plastic deformation (SPD), which is widely used in the technology of manufacturing machine parts, are considered. Theresearch objective is to justify the efficiency of the influence of vibration shock hardening treatment on improving the quality and performance of crankshafts (CS).Materials and Methods. The methodological studies included the validation of the vibration shock processing flowchart and the development of an analytic model for assessing the effect of processing on the change in the macrogeometry (warpage) of the CS.Results. Flowcharts have been developed for volumetric vibration shock finishing and hardening treatment of CS using a vibratory machine with a U-shaped work chamber. Its overall dimensions measure alike or exceed the overall dimensions of the CS being processed, and ensure the location of the shaft in such a way that its main axis, coinciding with the axis of the main bearing journals, is in the zone of the conditional axis of working mass rotation. The surface quality parameters were investigated during their processing on the UVG 4X10 vibratory unit according to the proven techniques using the dedicated tooling. It has been established that the vibration shock hardening treatment (ViHT) enables, due to plastic deformation of microroughness, to obtain a qualitatively new surface microrelief and to reduce its initial roughness, to drastically increase the surface microhardness of the CS main and rod journals; at that, it changes the stressed state of their surface layer. A calculated dependence is proposed to assess the total warpage of the CS strengthened under the ViHT, and its adequacy is confirmed. It is shown that the warpage of the shaft after the ViHT is due to the different tension of the rod and main journals of the CS at the level of Кн ≈ 0.6.Discussion and Conclusions. Vibration shock treatment of CS provides an improvement in the geometric and physicomechanical parameters of surfaces of the rod and main journals. As a result of processing all surfaces of the shaft, warpage does not exceed the permissible values established by the technical requirements. So, we can conclude on the efficiency of the considered method of hardening CS with the aim of increasing their operational properties.

This article will help to consider the problem of thermodynamic optimization of heat power equipment. Solving this issue will allow to increase the energy efficiency of thermal systems by reducing the cost of energy resources. There is a large number of methods for studying power plants, and we will combine two of them: the exergy method and the pinch method. Exergy analysis of thermal systems shows quantitative and qualitative characteristics of efficiency. The pinch method allows us to solve specific design problems to optimize the parameters of heat power facilities. The pinch analysis is based on enthalpy, which does not take into account the heat potential. We propose to conduct a pinch analysis of thermal energy sources using exergy, which can better assess the potential of heat fluxes and show the dependence of the energy of heat fluxes on the ambient temperature. The article provides an exergy analysis of a direct-flow boiler PP2650-255 GM using the pinch method. The results of our work show that in order to increase the energy efficiency of the boiler, it is possible to change the area of the heating surfaces of the economizer and air heater. Thus, exergy pinch analysis is an effective method for increasing the energy efficiency of heat power equipment.

Backgrounds. It is possible to obtain grinding balls production by cross-helical rolling method, with particular accuracy to their geometry. It is relevant to divide produced grinding balls nomenclature into 2 groups of geometric accuracy. It is recomend use of “particular accuracy” to balls intended for heat treatment into the fifth hardness grade. The study object is grinding balls. The research subject is process of grinding balls production on modern equipment with high geometric parameters achievement. The aim of this resurche is it structure the parameters to which accuracy of the grinding balls geometric dimensions on, determining their influence degree, as well as the maximum deviations for proposed group of high accuracy balls. Materials and methods. The study was carried out in conditions of the EVRAZNTMK JSC rail and beam workshop. Rolling was on modern ball-rolling mill 60- 120. The rolls were manufactured at 5-coordinate machining center NORMA L-45, and geometric parameters were controlling on FAROARM measuring machine. Results. Following limit of geometric accuracy were identified: the limit due to manufacturing quality of deformation tool, the limit in setting ball-rolling mill and the measurement limit. Total limit was calculated under for all sizes of obtained balls. The table with gradation of grinding balls into two groups: ordinary accuracy and high accuracy, indicating maximum deviations in size was compiled. Conclusions. The study confirms that at now it is possible to obtain increased accuracy balls, which, due to decrease in stress concentration, will be minimally subject to destruction during hardening and external influences.

Kandalaksha graben, located in the water-area of the White sea, is a part of the Onega-Kandalaksha paleorift of the Riphean time of foundation. It is filled with the terrigenous formations of the Terskaya suites ranging from 3 to 8 km by depth, while the age of the rocks of the Terskaya suite is still controversial, and according to different sources, ranges from 1300 to 670 Ma. This means that the time of the formation of Kandalaksha Graben is not precisely defined. In 2016, on the Tersky Bank of the Kola Peninsula, a sample of sandstones of the suite was selected. The age of the rock of 1390±25 Ma, i.e. the boundary of the early and middle Riphean, was determined by the K-Ar isotope method.. This corresponds to the time of the beginning of the stretching of the lithosphere and continental rifting. Quartz-microcline metasomatites formed on sand-shale spit of Terskaya suite in the zone of amethyst deposit of Cape Korablik gave the age of 821±170 Ma, determined by Sm-Nd method, and fluorite of the same rocks gave the age of 690±71 Ma. The last value is close to the age of the basalts from the Onega depression, defined by the same method. These data correspond to the momentum of stretching of the passive Timan margin of the Baltic area at the end of the late Riphean.

Abstract The stability of ferroelectric domain patterns at the nanoscale has been a topic of much interest for many years. We investigated the relaxation of the polarized state created by application of a local electric field using a conductive tip of a scanning probe microscope for the model uniaxial relaxor system SrxBa1−xNb2O6 (SBN) in its pure and Ce-doped form. The temporal relaxation of the induced PFM contrast was measured at various temperatures. The average value of the induced contrast decreases during heating for all investigated crystals. Below the freezing temperature the induced state remains stable after an initial relaxation. Above the freezing temperature the induced state is unstable and gradually decays with time. The stability of the induced state is strongly affected by the measuring conditions, so continuous scanning results in a faster decay of the poled domain. The obtained effects are attributed to a decrease of the induced polarization and backswitching of the polarized area under the action of the depolarization field.

Розроблено концепцію побудови транзисторного регулятора для електроприводів малої потужності з використанням оригінального принципу управління. Запропонований принцип регулювання близький до релейного або коливального типу електроприводу, проте відрізняється від нього більш високим ступенем інваріантності до змін моменту завантажень на валу приводного електродвигуна. Особливістю розробки є те, що регулятор електроприводу відпрацьовує не просто зміна величини на валу електродвигуна моменту або завдання - він практично відпрацьовує швидкість зміни збурень. Показано, що нова розробка електроприводу враховує особливості роботи основних вузлів механізованого та автоматичного обладнання для дугового зварювання електродом, але може бути використані і в інших об’єктах промисловості. Виконано виготовлення та випробування в реальних об’єктах зразків регуляторів, характеристики, яких при простому, але ефективному побудові задовольняє всім вимогам систем, які встановлюються в зварювальному обладнанні. Запропоновано розширити застосування розглянутого електроприводу при його реалізації в мікросхемном виконанні

A hypothesis has been put forward that it is possible to reduce the degree of splashing when surfacing into carbon dioxide due to the setting of the frequency characteristics of the oscillation of the weld pool. Equations are presented that are the result of theoretical research, on the basis of which an expression for the short-circuits frequency of the inter-arc gap in the process of surfacing by on a direct current is determined. On the basis of brief literature analysis of the works past years old its is showed that the frequency imposed on the welding pool has to detected by crystallization frequency near the crystallization front melt which is detected by a surfacing velocity and crystallization characteristics of weld pool metal. Due to the fact that for present day the strict theory of crystallization in the conditions outer oscillations haven't created, the dependencies for an amplitude-frequency characteristic’s determining which were got by different researchers have been presented. The example of calculation of an arc burning time and time of short circuit in period of surfacing process have been presented. On the basis of that, frequency of short circuits has been determined.

The paper considers an approach to development of methodology for complex modernization of a control system of power resources at construction engineering enterprises on the basis of modern information resources and technologies. An enlarged conceptual scheme of the control system of power resources has been proposed in the paper. The paper provides informatization principles of the control system and these principles are used for development of architecture for a corporative information and analytical system as a tool- technological complex designed for modernization of the control system of enterprise power resources.

Optical stochastic cooling (OSC) is a promising technique for the cooling of dense particle beams. Its operation at optical frequencies enables obtaining a much larger bandwidth compared to the well-known microwave-based stochastic cooling. In the OSC undulator radiation generated by a particle in an upstream “pickup” undulator is amplified and focused at the location of a downstream “kicker” undulator. Inside the kicker, a particle interacts with its own radiation field from the pickup. The resulting interaction produces a longitudinal kick with its value depending on the particles momentum which, when correctly phased, yields longitudinal cooling. The horizontal cooling is achieved by introducing a coupling between longitudinal and horizontal degrees of freedom. Vertical cooling is achieved by coupling between horizontal and vertical motions in the ring. In this paper, we present formulas for computation of the corrective kick and validate them against numerical simulations performed with a wave-optics computer program.

Coherent transverse beam oscillations in the Tevatron were analyzed with the model-independent analysis (MIA) technique. This allowed one to obtain the model-independent values of coupled betatron amplitudes, phase advances, and dispersion function around the ring from a single dipole kick measurement. In order to solve the MIA mode mixing problem which limits the accuracy of determination of the optical functions, we have developed a new technique of rotational MIA mode untangling. The basic idea is to treat each beam position monitor (BPM) as two BPMs separated in a ring by exactly one turn. This leads to a simple criterion of MIA mode separation: the betatron phase advance between any BPM and its counterpart shifted by one turn should be equal to the betatron tune and therefore should not depend on the BPM position in the ring. Furthermore, we describe a MIA-based technique to locate vibrating magnets in a storage ring.