6, 2021最新文献

{"title":"Investigation of closed cavity conditions in the bottom of cast rolls СПХН-60","authors":"B. O, S. L, Osipenko I, Usenko R, Repyakh S, Khrychykov V","doi":"10.34185/tpm.6.2021.06","DOIUrl":"https://doi.org/10.34185/tpm.6.2021.06","url":null,"abstract":"The paper investigates the possibility of preventing the occurrence of closed-type shrinkage shells in the lower necks of\u0000СПХН-60 iron rolling rolls by changing the thermophysical and dimensional parameters of the elements of the combined\u0000foundry mold, which is currently used in foundries.\u0000The research was carried out based on the results of thermography of real rolls of СПХН-60, adaptation of the obtained\u0000data and computer modeling of the process of hardening of cast iron rolls in the combined casting-sand mold, as well as\u0000the first developed parametric criterion of sequential hardening in the system of the lower neck of the roll and its barrel.\u0000The regularities of the complex influence of the diameters of the barrel and the lower necks of the rolls, the sizes and\u0000thermophysical parameters of the materials of the combined form on the sequence of solidification of these casting elements have been established. The obtained data indicate that increasing the level of thermophysical properties of the\u0000molding mixture for the lower neck of the roll within the limits of the use of currently known refractory non-metallic materials does not prevent the occurrence of a shrinkage shell in the lower neck of the rolls of СПХН-60 execution. Increasing the level of the heat-accumulating capacity of the forming mixture for the lower neck of the roll to 10000\u0000Ws\u00000,5\u0000/(m²С) will prevent the occurrence of a shrinkage shell in the lower neck of the rolls of СПХН-60 performance,\u0000but it is not expedient due to the appearance of a layer of bleached iron in the lower neck, which is unacceptable for any\u0000rolling mill.\u0000To solve this problem, it is recommended for СПХН-60 rolls to use shielding of the roll combined form at a certain moment of solidification of the melt in the barrel.\u0000Рurposeof the work is to investigate the possibility of preventing the occurrence of closed-type shrinkage shells in the\u0000lower necks of rolling rolls due to changes in the thermophysical parameters of their forming mixtures.\u0000Methodology.The work uses the method of thermography and computer modeling using the LVMFlow program.\u0000Originality.For the first time, the regularities of the complex influence of thermophysical and dimensional parameters of\u0000the elements of the combined foundry mold on the occurrence of a shrinkage shell in the lower neck of the СПХН-60\u0000rolling rolls were established.","PeriodicalId":144571,"journal":{"name":"6, 2021","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116904391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of the influence of dispersion of iron-containing component on technological properties of molding and rod mixtures.","authors":"Selivorstov V, D. Yu, Khrychykov V","doi":"10.34185/tpm.6.2021.07","DOIUrl":"https://doi.org/10.34185/tpm.6.2021.07","url":null,"abstract":"The presented results of researches of choice of rational method of receipt of ferruginous constituent of different dispersion are in bullet mills for formings and cored Iron-phosphatic a mixture of KHTS, and also influence of dispersion of\u0000dross on durability at the clench of mixture of this type.It was found that to obtain a highly dispersed iron-containing\u0000component of phosphate КHTS in the current production is the most rational use of mechanical method - ie grinding in\u0000ball mills, as it is effective both technologically and economically, given including the prevalence of this type of equipment. Each of the scale samples was loaded into a ball mill according to the instructions and ground for 40 minutes.\u0000Every 5 minutes, the mill was stopped and a sample weighing 100 grams was taken, after which the particle size distribution of the scale in this sample was determined. According to the literature, there is no generally accepted classification according to the particle size distribution [7]. This is due to the variety of purposes for which the particle size distribution of a material is determined. The particle size distribution of various materials is set by standards and technical\u0000conditions, which are developed for each individual consumer of this raw material. The normative document for determining the particle size distribution of metallurgical plants is currently unknown. The granulometric composition of rolled\u0000scale after grinding it in a ball mill was determined. The specific surface area of scale at the level of 2300-2500 m2 / g is\u0000achieved after 20 minutes of grinding in ball mills, which confirms the technological feasibility of their use for grinding the\u0000metal component of iron-phosphate HTS. The obtained data on a sufficiently high compressive strength of samples of\u0000iron-phosphate mixture, reaching 3.5 - 4 MPa, and is quite acceptable for use in the mixture for the production of bulk\u0000sand molds and rods, showed the prospects for further research in this direction .","PeriodicalId":144571,"journal":{"name":"6, 2021","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126133384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research of thermal energy processes during silicon carbide production in the resistance furnace","authors":"D. I, Zhadanos O","doi":"10.34185/tpm.6.2021.03","DOIUrl":"https://doi.org/10.34185/tpm.6.2021.03","url":null,"abstract":"Thegoal. Silicon carbide is one of the most essential artificial inorganic materials widely used to produce abrasive instruments, high-temperature heaters, fireclay ceramics, and metallurgy. The most amount of silicon carbide produces in\u0000the resistance furnaces. One of the issues of the silicon carbide production process is the lack of supervisory of thermal\u0000state in the furnace working space, which does not always allow for select rational electrical modes and accordingly get\u0000the material of appropriate quality. One of the methods to solve this issue is computer modeling the thermal state of the\u0000resistance furnace. Therefore, the goal of this research is the development of a computer model of the thermal state in\u0000the reaction zone of the resistance furnace, that further allows the development of technological recommendations concerning modes of conducting the process of obtaining silicon carbide. In addition, the development of a mathematical\u0000model of the dynamics of the thermal state of the resistance furnace opens up new opportunities for improving the existing automated control systems, which is very important from the point of view of the implementation of the Industry 4.0\u0000paradigm at the enterprises of the mining and metallurgical complex of Ukraine.\u0000Methodology. The thermophysical model of the silicon carbide production process in the resistance furnace was developed. By finite difference method, the dynamics of the thermal state of the reaction zone in the furnace are computed.\u0000Resultsandscientificnovelty. Zones of the existence of products of carbothermic reduction of silica due to the heat\u0000generated when an electric current is passed through the furnace core are sized up by results of modeling, and the\u0000temperature front of the progress of the reductive reactions was detected.\u0000Practical value. The developed model allows for evaluating the influence of supplied power dynamics on the reduction\u0000products size zones, obtaining the analytical dependences of changes in the thermal state of the reaction furnace zone,\u0000and thereafter developing the technological recommendations concerning silicon carbide production process performance and improvements for the furnace automated control system. The structure of control of the thermal modes of\u0000the resistance furnace and the control computer complex based on Siemens technology is proposed.","PeriodicalId":144571,"journal":{"name":"6, 2021","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128134611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical and foundry propertiesof Cu-Sn-Al system alloys","authors":"Kimstach T, U. K, Repyakh S, Mazorchuk V, Usenko R, Ivanova L","doi":"10.34185/tpm.6.2021.05","DOIUrl":"https://doi.org/10.34185/tpm.6.2021.05","url":null,"abstract":"Tin-aluminum bronze containing Sn - up to 6.73% and Al - up to 7.53% (by weight) physical and\u0000casting properties determination.\u0000Methodology. Melting has been carried out in graphitecrucible in induction furnace under charcoal layer. Alloys liquidus\u0000and solidus temperatures have been investigated by thermography results of solidifying melt. Free (С) and absolutely\u0000difficult (АЗ) linear shrinkage values and alloy transition temperature from plastic to elastic state during cooling in mold\u0000have been studied by conventional methods. Bronzes fluidity has been estimated by the spiral sample filled channel\u0000length according to GOST 16438. Bronze BrO3A3 tendency to burn and to hot and cold cracks formation has been\u0000evaluated by samples surface visual examination results. Cast bronze specific density has been determined by calculation. Studied alloys mechanical properties have been calculated based on corresponding samples tests results at their\u0000impact bending at room temperature in accordance with actual standards. Alloys chemical composition control has been\u0000carried out on precision analyzer EXPERT 4L on specimens cut from club-shaped samples. Microstructural studies\u0000have been performed on metallographic microscopic samples prepared by standard methods on optical microscope\u0000Neophot-21. Approximation reliability value and corresponding dependences have been built using EXEL computer program.\u0000Results.According to qualitative and quantitative indicators and system Cu-Sn-Al bronzes with Sn content up to 6.73%\u0000and Al content up to 7.53% physical and foundry properties assessments, it has been determined that among possible\u0000tin and aluminum content in Cu-Sn- Al the most promising is bronze with 3...4% (by weight) of these alloying components each.\u0000Originality.For the first time number of physical and foundry properties of Cu-Sn-Al system bronze (with Sn content up\u0000to 6.73% and Al up to 7.53%) have been determined. It has been first established that such bronzes linear shrinkage,\u0000transition temperature from plastic to elastic state during cooling after solidifying and impact bending value at normal\u0000temperature depend on their structure, i.e. phase composition determined by its alloying elements content in bronze.\u0000Practical value.According to studies of physical and foundry properties results, bronze BrO3A3 has been recommended to be used as casting material","PeriodicalId":144571,"journal":{"name":"6, 2021","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130898466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}