Traditional Technological Processes Research Articles

PRODUCTION OF CARBONACEOUS MATERIALS USING COAL TAR RESIN AND INVESTIGATION OF THEIR SURFACE PROPERTIES

The traditional technological process for creating highly porous materials from carbonaceous raw materials involves two stages of thermal treatment: carbonization (pyrolysis) and activation (gasification), aimed at forming a porous structure capable of adsorption. Combining both stages into a single process with chemical activation allows for efficient raw material utilization and control of the material's porous structure at different levels, providing the ability to customize its characteristics. The choice of a chemical activator depends on the type of raw material and the required characteristics of porous carbon materials. In this study, it is established that the analysis of surface properties of highly porous carbon materials synthesized from coal tar pitch, obtained by distillation of coal tar resin from JSC "Shubarkolkomir," confirms the outstanding operational characteristics of this material. The application of a combined process of carbonization and activation of coal tar pitch at an optimal temperature in an inert atmosphere leads to the formation of porous carbon materials with a high specific surface area: 561 (traditional method), 789 (chemical activation), and 881 m²/g (templating method), as well as a pore volume of 0.30; 0.40; and 0.48 cm³/g, respectively. This work not only expands the technological methods of obtaining carbon materials from coal tar resin but also underscores their potential for improving soil structure and increasing the efficiency of agricultural production.

DEVELOPMENT OF A MODULAR TECHNOLOGICAL PRODUCT ASSEMBLY

The article reveals the shortcomings identified in the development of the traditional technological process of product assembly. These shortcomings increase the labor intensity of its development and reduce its quality. It is proposed to use the principles of modular technology, allowing to present the product a set of basic modules of surfaces and binding modules in order to eliminate the above drawbacks in the development of the product assembly process. The availability of this information allows reducing labor intensity and improving the quality of product assembly in its development.

Improvement of the performance of a multi-blade tool based on selective equipment with cutting ceramics

The increasing pace of industrial production for the production of products and the widespread complexity of the designs of manufactured products, justified by scientific and technological progress, pose a permanent task to the metalworking industry to improve technological processes in order to reduce the time of manufacturing parts and material costs. These requirements lead to the desire of manufacturers to reduce traditional technological processes and significantly increase the processing speed. In such conditions, traditional tool materials are often not applicable, while some materials that were previously not in demand due to the lack of necessary technological conditions are becoming increasingly relevant. One of such materials is cutting ceramics – a material that has the highest efficiency at high cutting speeds, but due to the brittle nature of the fracture provides low stability when used in non-rigid technological systems, under high loads and insufficient attention to the equipment of the tool with ceramic cutting plates. The article is devoted to improving the performance of a multi-blade tool based on selective equipment with ceramic cutting plates during the finishing of the working surfaces of high-precision cast-iron body parts. In the course of this study, the problems of using a multi-blade tool for milling high-precision planes were identified, a way to solve the identified problems was determined, a device was created to determine the microstructural parameters of cutting ceramics based on the known dependence of microstructural characteristics on the electrical resistivity of oxidecarbide cutting plates, a method was developed for selectively equipping a multi-blade cutting tool with oxide-carbide ceramic cutting plates. The effectiveness of the proposed solutions is confirmed by experimental studies.

Some features of automatic electric arc surfacing under the flux with controlled periodic change of modes

The development and application of automatic electric arc surfacing under flux with controlled periodic change of modes makes it possible to expand significantly the possibilities of traditional technological processes of surfacing. The carried out experimental investigations make enabled us to determine the advantages of the welding process with modulation of modes in comparison with welding in stationary mode. It is established that the parameters of the modulated welding current (frequency, sparseness) determine the degree of influence on the physical and mechanical characteristics of the welded metal and in most cases improve them compared to the characteristics of stationary mode. The result of the analysis defines that in the pulse mode it is possible to achieve the reduction of inclusions from the composition of the flux by almost 30%. This reduction is an additional factor in ensuring the characteristics of strength (hardness, wear resistance) of the weld roller and weld.

FDM 3D Printing Process - Risks and Environmental Aspects

The application of the 3D printing processes is continuously increasing due to their large number of technical and economic advantages when produce prototypes, but in the mass fabrication as well, especially for metal printing of low dimension products. The process produces pollution as all technological processes. Noise, fume and polymer wastes are the main elements which exit from the process and they are not products. The types and the volumes of those pollution emissions depend on the process parameters. The paper presents the results of FDM process emissions analysis. It was recorded the noise for different stages of the printer functioning. It was measured the volume and the contents of the fume produced during the extrusion of the polymer, for PLA polymer and for ABS polymer filaments. Specific risks were analysed and conclusions were reported. The measurement was done for a random chosen product and the results were compared with the pollutant emissions from traditional technological processes applied to erect the same type of product. It has been concluded that the noise emitted during the FDM printing is about 82-85% of the noise produced when apply milling to create similar shapes and dimensions (it was recorded values for the sound pressure in a large range: 42-68 dB, depending on the working regime). Regarding the fume emission, the intensity of emission was up to 40% higher in the FDM process comparing to the milling process. That was explained as being a direct result of the fluid-viscous state in which the material is put during the printing process. When discuss about the risks, most of the main identified risks in the milling and/or extrusion process were almost inexistent in the FDM printing. Electrical injuries and heat injuries are the main risks to which the operator is exposed. Mechanical injuries are sensitively lower than in the traditional processes, as milling The FDM process is safer and produces lower material wastes. It can be concluded that the FDM printing process has lower impact with the environment and with the operator.

IMPROVEMENT OF TECHNOLOGICAL PROCESS OF DRILLING THIN SHEET STEELS

This article considers the technological process of drilling holes in sheet metal. The existing typical technological process, with detailed analysis, provides grounds for substantiating the idea of an innovative solution. There is a connection between the improvement of economic indicators of this technological operation with the change of geometric parameters of the tool. The comparison of existing technological processes, operations, and transitions of production of round openings with the use of spiral drills is given. The traditional technique involves a clear sequence of the technological process with the use of tools for marking, kerning, and sequential use of screw drills of different diameters. Therefore, after the previous operation of marking the center of the two holes, perform the operation of kerning. The core (recess in the metal) prevents the deviation of the small diameter screw drill from the marking lines. After the above steps, the traditional technological process involves drilling a small diameter hole in order to direct the main tool in the right direction. To make the main hole perform special sharpening of the working part of the twist drill so that the diameter of the Central part of the tool is equal to the diameter of the first guide hole to avoid further displacement of the main hole and the next operation is to drill the hole to the desired diameter. As a result, the article raises the topic, given the widespread use of sheet metal, including in the agricultural sector, the feasibility of using an innovative idea to improve the technological process associated with the processing of sheet material, namely thin metal sheets. It is worth noting that for example, we consider a material that is characterized by its versatility, namely steel Ст 3. Despite the numerous sources devoted to the study of improving the drilling process, there are a number of issues, including the extension of this direction surfaces with a covering and without it, various thicknesses within the thin-walled hire. The most significant result of the improved technological process of drilling will be used in the system of efficient maintenance of agricultural machinery.

Simulation of expansion a branch-pipe with «blinds» by the pressure of magnetic field

Thin-walled tubular structures that are used to connect units and supply gas or liquid are widely used in aircraft devices. Aircraft pipelines have a complex cross-sectional profile, large differences in size, the presence of different holes, shape changes, stiffeners, etc. Often, such parts have insufficient indicators of durability during the process of maintenance. The main reason is the use of traditional technological processes in the production of such parts. This paper presents an analysis of electrodynamic processes during magnetic - pulse «expansion» of thin-walled tubular parts. To carry out the technological process, separation operations plus calibration, a branch-pipe was chosen, which serves to mix the flows of hot and cold air in the aircraft air conditioning system. A prerequisite for the achievement of this goal is high demands on the quality of the internal and external surfaces, shape retention, minimal thinning of the walls.

Features of technology of milk production and its processing in the modular shop

Increasing the production of milk and dairy products to provide the population of country with complete-fl edged food is an important task, which requires not only increasing the productivity of animals, but also using energy- and resource-saving technologies in their production to increase the eff ectiveness and profi tability of the industry. New solutions for the development of agricultural enterprises should take into account the requirements of time not only to increase production, but also to reduce prime-costs for it. In a market economy in the fi eld of agriculture in particular in dairy farming in the chain from the supplier of raw materials to the sale of the fi nal product, the least profi table is the production of raw materials. Therefore, the use of mini dairy shops for processing milk directly in the conditions of an agricultural enterprise should increase the eff ectiveness of dairy cattle breeding. The issues of effi ciency of milk processing under the conditions of an agricultural enterprise using a modular dairy shop for the production of fi nished dairy products have been considered in the paper. In the considered modular dairy shops traditional technological processes for the production of pasteurized milk and sour cream are used. Modular dairy shop KOLAKS-5001 only processing pasteurized milk with fat content of 3,71 %, packaged in plastic bags and modular dairy shop KOLAKS-5002 processing pasteurized milk 2,5 % fat, packaged in plastic bags and sour cream 20 % fat, packaged in plastic cups. As a result of the evaluation of the effi ciency of using a modular dairy shop, it was found that it will increase the eff ectiveness of milk production and pay back for equipment costs within 1,5 months.

The results of water droplet erosion tests of ion-plasma coatings formed on titanium Ti-6Al-4V alloy samples manufactured by using 3D-printing and traditional technological process

The paper presents the results of erosion tests and metallographic studies of titanium alloy samples manufactured by using 3D printing and traditional technological methods without coatings and with various types of ion-plasma coatings. As a result of the tests, the kinetic curves of erosion wear of the studied alloys and coatings were obtained, showing that the best type among those considered is a DLC (Diamond Like Carbon) coating, which increases the relative erosion resistance of uncoated samples in incubation period duration of the water droplet erosion process by not less than in 1.8 times.

NUMERICAL MODELING AND SOFTWARE FOR DETERMINING THE STATIC AND LINKAGE PARAMETERS OF GROWING BODIES IN THE PROCESS OF NONSTATIONARY ADDITIVE HEAT AND MASS TRANSFER

Currently, methods of three-dimensional printing of products from polymer, metal and ceramic materials are widely used. Layer-by-layer synthesis technologies make it possible to obtain high-quality products with sufficiently high mechanical characteristics close to those realized using traditional technological processes. A related problem is solved, including calculating the temperature in the product and the operation area surrounding it in a flat setting based on two different approaches. For a layer-by-layer extensible body, the unsteady heat conduction problem is stated. At each step, the height of the computational region increases due to the filling of a new layer of powder. One time step of the calculation is determined by the interval between two consecutive passes of the laser. The temperature distribution found at each step is used as the initial conditions for the calculations at the next step. The temperature field obtained as a result of solving the problem that is implemented in the product in question with a step of 1000 (after applying and melting 1000 layers) is further compared with the solution of the quasi-stationary problem for the finite dimensions product. Using the example of the simple geometry taken, it is shown that a quasi-stationary solution can provide a satisfactory estimate of the macroscopic thermal state of the growing product.

Comparative erosion tests results of titanium alloy Ti-6Al-4V samples obtained by using 3D - printing technology and manufactured by the traditional technological method

Rotating blades of steam turbines and compressors operate in conditions of various damaging factors, including shock-dynamic impacts of liquid droplets contained in steam or in air. One of the most promising ways to reduce damage from water droplet erosion can be the application of the 3D - printing technology that will allow to replace damaged parts of structural elements, as well as cut repair costs and prolonging the service life of the equipment.The aim of present work was to determine the possibility of using the 3D - printing technology of the turbine blades for use in power engineering. The main task of the work was to check samples of the material obtained by this method for water droplet erosion resistance, which is one of the regulated tests type at the turbine blades design stage.This paper presented the results of water droplet erosion process experimental studies of the titanium alloy Ti-6Al-4V samples prepared by the method 3D - printing and by the traditional technological process at a collision velocity Cimp = 300 m/s with a monodisperse flow of liquid droplets with a diameter dd = 1000 μm. Erosion tests were carried out by using a set of research equipment URI «Hydroshock rig «Erosion-M» NRU «MPEI». It has been established that the erosion resistance for the incubation period duration of the Ti-6Al-4V titanium alloy samples manufactured by the 3D - printing method is 1.4 times less than for the samples manufactured by the traditional technological process. The data obtained can be used in the future in the development of complex passive methods for protection steam turbines and compressors last stages rotating blades: creation of replaceable erosion-resistant inserts by 3D - printing with a protective coating.

Indigenous culture as a knowledge system

Complex concepts such as cultural identity, gender issues and the effects of colonialism, politics, and power structures on societies form part of the debate around indigenous culture as a knowledge system. This article makes a contribution to the debate by addressing cultural issues encountered during a cross-cultural research project based in India and South Africa. The authors reflected on some of the conceptual issues they grappled with during their research. The project involved the documentation, study and understanding of the extent in which indigenous knowledge systems (IKS) and modern technologies were utilised in the traditional manufacturing processes of artisans in general and potters in particular. The roles and functions of IKS as used during the production of artefacts were included in the study. This perspective was coupled with a study on the artisans' attitude towards and understanding of science (PAUS) while conducting their traditional technological processes. The combined approach provided a method that allowed researchers to develop interventions that capitalised on existing skills, practices and social relationships rather than undermining them, thus contributing to their sustainability. The project, at the same time, focussed on redefining the characteristics of "knowing" (of knowledge) as not just a mere contemplative gaze, but also as a practical activity. By focusing on artisans, the question of knowledge was placed in the two spheres of knowledge production: "theory" (epistemology) and "practice". This approach attempted to address and discuss some academic notions based on culture; including a variety of aspects that broadly constitute the "concept" of culture. As these notions continuously alter with changing academic insights they are constantly re-defined by academics and researchers.

Approaches to the production and use of microbial transglutaminase in emulsified meat and vegetable systems

In the technology of traditional and new forms of food, the modification of structure of proteins is carry out in two opposite directions: the hydrolytic destruction of high-molecular polymers and the artificial creation of polymeric structures of high molecular mass. The transglutaminase preparations (protein-glutamine (-glutamyltransferase, EC 2.3.2.13, TG) are used in practical work for realization of the second direction. The main mechanisms of action are polymerization reactions, which lead to a change in the hydrophobicity of protein molecules. The main catalyzed reactions are acyl transfer, binding between glutamine and lysine residues of proteins and deamination. The authors analyzed the approaches to the preparation, properties and studied the joint effect of temperature and pH on the activity of the commercial preparation Revada TG 11 with the application of an enzymatic colorimetric test. The authors studied combined stuffing systems based on beef, pork, poultry mechanical deboning, as well as replacing part of the raw material with protein-carbohydrate compositions with Revada TG 11. The results were used to develop simulated meat systems of biopolymer compositions (SMSBC), approximate in structure and properties to the gels formed by actin and myosin during extraction from myofibrils under the traditional technological processes of meat products production - maturation, salt curing, fine meat grinding. SMSBC includes lupine flour bio-activated by germination, a preparations of dietary fiber as well as a preparation of transglutaminase Revada TG 11. The protein components of the secondary raw materials during the processing of milk such as sodium caseinate, and also whey were used to balance the amino acid composition of the food systems. For practical use, the following options for SMSBC introducing into the composition of minced meat emulsions were recommended by the authors: in the form of hydrated biopolymer dispersion at cutting; in the form of a previously heat-treated gel.

From the research on clay processing and the use of pottery products among the population of the Lusatian culture in the Lublin region

In the Bronze Age and Early Iron Age pottery making was among the most important branches of domestic production. In the Lublin region there were numerous deposits of clay from which this raw material was extracted and then underwent special processing. Various techniques were developed in the course of making pottery vessels and creating other clay items. Pottery production was done by members of respective families, and high importance in this regard is attributed to women. Traditional technological processes were replicated and there were local peculiarities when it comes to the forms and ornamentation of the products. It is likely that for both the potter and the users of his/her products the implementation of magical actions when working with clay was important.

Three Dimensional Finite Element Simulation of Cutting Forces and Cutting Temperature in Hard Milling of AISI H13 Steel

Compared with the traditional technological process, hard milling of hot work tool steel (AISI H13) can significantly improve the physical/mechanical performances of machined components. A three dimensional (3D) finite element (FE) simulation model was built in this research to investigate the complex nonlinear process. First, the geometric model of workpiece was established considering the previous machined surface profile in actual milling process. Secondly, the prediction validation of the simulation model about hard milling process was verified by comparing the simulated cutting forces with the experiment results. Finally, the effect of cutting speed and feed rate on cutting forces and cutting temperature were researched by using the FE simulation model. The results indicate that cutting forces increase with the increase of feed rate, while cutting temperature increases with the increase of cutting speed. The effects of cutting speed on cutting forces and feed rate on cutting temperature are not significant. The simulated temperature is much lower than the austenitizing temperature of AISI H13 steel which means white layer is unlikely to be formed under the cutting conditions used in this study. The research can contribute to the fundamental understanding of mechanism and optimization of cutting parameters in hard milling.

ВИЗНАЧЕННЯ ЕФЕКТИВНОСТІ РЕЖИМУ ТЕПЛОВОГО ОБРОБЛЕННЯ МОЛОЧНОЇ ОСНОВИ У ТЕХНОЛОГІЇ СИРКОВИХ ДЕСЕРТІВ ДЛЯ ЛЮДЕЙ, СХИЛЬНИХ ДО АРТЕРІАЛЬНОЇ ГІПЕРТЕНЗІЇ

В роботі наведено результати визначення ефективності параметрів теплового оброблення молочних сумішей у технологіях сиркових десертів для людей, схильних до артеріальної гіпертензії (АГ). Вибір режиму пастеризації зумовлюється не тільки необхідністю знищення мікрофлори, а й особливостями технологічного процесу виробництва цільових молочних продуктів.
 Обґрунтування режимів теплового оброблення молочної сировини є одним із важливих етапів при розробці та удосконаленні технологій кисломолочних продуктів взагалі, і сиркових десертів, зокрема.
 Дослідження проводили за допомогою чашкового методу, посівом підготовлених зразків в розплавлене поживне середовище з подальшим культивуванням. Перевірку ефективності режимів теплового оброблення знежиреного молока, збагаченого фруктозою та/або рисовим борошном для дитячого харчування, здійснювали розрахунковим методом за співвідношенням КМАФАнМ до та після пастеризації.
 В результаті експериментальних досліджень встановлено раціональні режими теплового оброблення молочних сумішей при виробництві сиркових десертів для людей, схильних до АГ;показановідсутність впливу фруктози та рисового борошна для дитячого харчуванняна ефективність пастеризації;обґрунтовано можливість та доведено доцільність використання традиційних технологічних режимів теплового оброблення при виробництві сиркових десертів для людей, схильних до АГ, а отже – відсутність необхідності встановлення додаткового обладнання у технологічній лінії.

The study of technological opportunities of the new sorbent microcrystalline calcium hydroxide

In this article there was confirmed the possibility of obtaining domestic lime sorbent on the basis of the microcrystalline calcium hydroxide corresponding to their physical and chemical properties to the best foreign analogues. There were analyzed the parameters of the traditional technological process of lime slaking. In the laboratory conditions there was developed a damping technology, allowing to get the lime sorbent with large adsorption surface.

Advanced Graded Protective Coatings, Deposited by EB-PVD

Electron beam technology (EB-PVD) and equipment for one-stage deposition of advanced graded protective coatings using a composite ceramic ingot for evaporation are described. This technology allows replacing the flat interface between coating layers by a graded transition zones and achieve of a high degree of reproducibility of the composition, structure and lifetime of the functionally graded coating in compare with traditional multi-stages technologies of protective coating deposition.A design of the composite ceramic ingot is considered, as well as the ability to regulate in a broad range the composition, structure and properties of all levels of the graded protective coating including transition zones and coating layers. Examples and variants of advanced graded protective coatings with their structures and properties are given (thermal barrier, hard erosion-resistant and damping coatings) for aerospace and gas-turbine industry application deposited by one-stage EB-PVD process. Total cost of one-stage EB-PVD deposition process at least 2 times less in compare with traditional technological processes of protective coating deposition due to using only one EB-PVD unit and elimination of multistage nature of process cycle.Laboratory and productive electron-beam units designed and manufactured at ICEBT are considered. Development of modern protective coatings, technologies and equipment for their application is focused, primarily, on improvement of the durability and main service properties of the coating/protected item system, ensuring a reliable reproducibility of the coating structure and properties, shortening the cost and time of the entire technological cycle of their deposition. The existing traditional technologies of deposition of multilayer protective coatings, for instance, thermal barrier coatings (TBC), containing a oxidation-resistant metal bond coat and outer low thermal-conducting ceramic layer, are multi-stage, with combination of such processes as diffusion saturation, galvanic coating, plasma spraying and electron beam deposition [1-3]. Use of diverse expensive equipment, availability of intermediate mechanical and thermal treatments, as well as the operations of surface cleaning, apply considerable limitations both on widening of the sphere of such coating application, and their further development in terms of improvement of the structure and properties. The one-stage electron beam technology developed at ICEBT for deposition of advanced protective coatings based on evaporation of a composite ingot and allowing deposition of functionally graded coatings in one process cycle, meets the above goals to a considerable extent [4,5]. The technology is based on the use of the known phenomenon of fractionating at evaporation of multicomponent systems, containing elements with different melting temperature and vapour pressure, and their subsequent condensation under vacuum, allowing the flat interface, for instance between the metal and ceramic layers, to be replaced by a transition zone of the graded composition and structure. Fig.1 gives the schematic and appearance of a composite ingot used for one-stage deposition of advanced graded protective coatings in vacuum by its electron beam evaporation from one crucible. The ingot base material determines the purpose of the graded coating. For instance, Al2O3, TiC, TiB2, B4C, MgO, etc. can be used as the base of the ingot for deposition of hard wear-resistant, erosion-resistant and damping coatings. For the case of TBC, this is zirconium dioxide with additives

Theoretical and experimental investigation of the multilayer tube drawing

The paper concerns drawing of a multilayer tube through a conical die. The drawn material composed of two steel tubes separated by a rubber tube. This type of part is widely used in automotive industry as silentblocks. The traditional technological process is based on mounting of a short rubber sleeve between two steel sleeves. The new idea of silentblocks manufacturing involves drawing of a long steel-rubber-steel tube. To examine the process, experimental and theoretical investigations are performed. In the theoretical analysis a steady state elastoplastic finite element method is employed. The problem is formulated in the Eulerian reference frame. The solution consist of the minimization of the deformation power with respect to a kinematically admissible velocity field and the integration of the stress-rate constitutive equations. The stress rate equations are integrated in the final configuration without linearization. Theoretical results are compared with experimental data for drawing of a steel-rubber-steel tube.