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This study investigated the changes in foundries and production techniques of modern and contemporary Korean artistic bronze constructions from the 1910s to the 2000s. To determine the characteristics of foundries and changes in alloy composition based on era, interviews with key sculptors and foundry technicians, analysis of archival materials related to casting, and nondestructive X-ray fluorescence analysis of 92 bronze sculptures by Manlin Choi, were conducted. This study found that foundries for artistic bronze underwent technical and organizational changes from the 1910s to the 2000s. Modern casting techniques and foreign technologies have been introduced since the late 1960s that have resulted in various production methods. The portable X-ray fluorescence analysis of Manlin Choi's 92 bronze sculptures revealed distinct differences in alloy composition depending on the foundry, findings that have also been supported by records (contracts, receipts, payment confirmations). This study systematically organizes the changes in foundries and production techniques of modern and contemporary Korean artistic bronze, identifying correlations between alloy composition and foundries, and is expected to provide important data for the future conservation and scientific authentication of artistic bronze. [ABSTRACT FROM AUTHOR]

Abstract This study investigated the changes in foundries and production techniques of modern and contemporary Korean artistic bronze constructions from the 1910s to the 2000s. To determine the characteristics of foundries and changes in alloy composition based on era, interviews with key sculptors and foundry technicians, analysis of archival materials related to casting, and nondestructive X-ray fluorescence analysis of 92 bronze sculptures by Manlin Choi, were conducted. This study found that foundries for artistic bronze underwent technical and organizational changes from the 1910s to the 2000s. Modern casting techniques and foreign technologies have been introduced since the late 1960s that have resulted in various production methods. The portable X-ray fluorescence analysis of Manlin Choi’s 92 bronze sculptures revealed distinct differences in alloy composition depending on the foundry, findings that have also been supported by records (contracts, receipts, payment confirmations). This study systematically organizes the changes in foundries and production techniques of modern and contemporary Korean artistic bronze, identifying correlations between alloy composition and foundries, and is expected to provide important data for the future conservation and scientific authentication of artistic bronze.

The need to reengineer the process for manufacturing sand cores in the conditions of the subsidiary enterprise "Casting and Mechanical Plant" (Tashkent) is due to the fact that the existing process at the Casting and Mechanical Plant (CMP) has disadvantages that affect the quality and efficiency of product output. For the sand core, which is used in the production of railway wheels, the number and diameters of ventilation holes for air exchange and injection holes for introducing the core mixture are determined. The design of a core box for the production of sand cores using cold-box technology has been developed, the use of which at CMP made it possible to increase productivity by 20%, reduce losses from defects in the manufacture and assembly of cores from 8 to 2%, and reduce the cost of disposal of waste cores by 80–90%. [ABSTRACT FROM AUTHOR]

This essay reviews the discovery of three sites where deposits of bronze fragments have been found, in the Roman cities of Pisaurum, Sentinum and Potentia. Each site yielded small bronze fragments and some tools, which lead us to suppose that these were sites of Late Antique foundries, where large bronze statues and other bronze objects were broken up to be remelted. The foundries were located on land previously occupied by taverns in the forum area or by residential quarters. This means that the urban plan of the cities had already been partially transformed, probably due to Christianisation and the construction of churches, which became the new community centres, to the detriment of the older areas of the forum. The rampant poverty and shortage of raw materials, especially metals, made foundries indispensable and, consequently, their widespread presence, even within the cities, probably became customary. Perhaps the numerous bronze fragments found in other centres of the region should also be interpreted in this same sense, as indications of foundries, even if the structures where the metal was worked have not been preserved.

Copyright of Revista Transdisciplinaria de Estudios Sociales y Tecnológicos (RTEST) is the property of Editorial Exced and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The requirements placed on the foundry industry are mainly related to the need to maintain an appropriate quality–price ratio of the product and to maintain an appropriate production regime that takes into account modern legal solutions related to environmental protection. This work is part of the trend of searching for new or previously unused materials from renewable sources in moulding sand technology. This article concerns the possibility of using barley malt in moulding material technology as a binding material. The presented work contains the results of research on the release of gases during casting, where high temperatures cause the decomposition of chemical substances. The tests confirmed that moulding sands with barley malt as a binder do not cause excessive emissions of harmful gaseous products when pouring moulds with liquid casting alloy. The volume of gases formed was smaller than that of commonly used moulding sands with other binders. The total volume of gases produced and the kinetics of their release indicate that casting in this type of moulding sand did not cause any technological inconvenience or casting defects of gaseous origin. This was confirmed by research involving obtaining iron castings in industrial conditions using barley malt as a binder in moulding sand technology, which were then subjected to visual assessment and roughness analysis. [ABSTRACT FROM AUTHOR]

The primary objective of this study is to optimise operating efficiency and minimise waste within a core foundry shop through the application of lean manufacturing techniques. The research emphasises the significance of Artificial Neural Networks (ANNs) in aligning an expert assessment matrix with lean tool rankings, particularly in addressing the challenges associated with fu//y logic-based leanness computation. The expert assessment matrix was constructed with the entropy approach for generating weights and the TOPSIS ranking algorithm for evaluating lean tools. The use of the TOPSIS technique resulted in a notable level of agreement, with a percentage of73.42%, and a corresponding level of disagreement of26.57%, when compared to the expert evaluation matrix developed for the assessment of lean tools. The expert assessment matrix that was produced was utilised in the analysis of the efficacy of several lean tools inside a foundry core manufacturing line. The research suggests the implementation of an automated conveyor system for the transportation of several cores, which would lead to the optimisation of floor space, enhanced safety measures, and more schedule flexibility. The findings of this study reveal a significant decrease of 79.6% in non-value-added activities (NVA), a notable improvement of62.66% in process efficiency, a substantial reduction of66.66% in waiting times, a considerable decrease of 35% in personnel requirements, and a significant cost reduction of 45%. A three-month accident-free workplace demonstrated the efficacy of the safety strategy. [ABSTRACT FROM AUTHOR]

Foundries, to the same extent today as in the past, represent one of the strategic branches of all industry. In fact, all aspects of modern life depend on the casting and production of brake discs, medical implants, marine engines, and even aircraft components like turbine blades. Foundries provide supplies to all sectors of modern industry, including automotive, aircraft, medicine, power generation, etc. The Slovak economy largely depends on the automotive industry for which casting is necessary. Cast components are used not only for engines, chassis, and drives but also in vehicle bodies. This article reports information on the current number of foundries in Slovakia, the number of produced casting tons and melting methods, the casting techniques in various foundries, and the types of cast metals. It considers the income of individual foundries, the impact of the economic situation, and assumptions regarding further development. [ABSTRACT FROM AUTHOR]

Refractories are the basic material for the construction of the lining of a melting furnace used, among other things, in the foundry industry. The article describes a comparative study of the influence of the type of moulding on the quality of the finished refractory product. A method for making products from refractory materials was proposed and a test methodology was developed. The results, based on a classic study of the quality of these materials, confirm a strong influence on the quality of the materials obtained in terms of reduced porosity and homogeneity of pore size.

This work aims to conduct an analysis to find opportunities for the implementation of software incorporating the concept of digital twins for foundry work. Examples of implementations and their impact on the work of enterprises are presented, as is a definition and history of the concept of a digital twin. The outcome of this work is the implementation of software that involves a digital copy of the author's device, created by the "Łukasiewicz" Research Network at the Krakow Institute of Technology. The research problem of this scientific work is to reduce the number of necessary physical tests on real objects in order to find a solution that saves time and energy when testing the thermal expansion of known and new metal alloys. This will be achieved by predicting the behavior of the sample in a digital environment and avoiding causing it to break in reality. Until now, after an interruption, the device often continued to operate and collect data even though no current was flowing through the material, which could be described as inefficient testing. The expected result will be based on the information and decisions obtained by predicting values with the help of a recurrent neural network. Ultimately, it is intended to predict the condition of the sample after a set period of time. Thanks to this, a decision will be made, based on which the twin will know whether it should automatically end its work, disconnect the power or call the operator for the necessary interaction with the device. The described software will help the operator of a real machine, for example, to operate a larger number of workstations at the same time, without devoting all their attention to a process that may last even for hours. Additionally, it will be possible to start work on selecting the chemical composition of the next material sample and plan its testing in advance. The machine learning handles model learning and value prediction with the help of artificial neural networks that were created in Python. The application uses historical test data, additionally retrieves current information, presents it to the user in a clear modern form and runs the provided scripts. Based on these, it decides on the further operation of the actual device. [ABSTRACT FROM AUTHOR]

This essay reviews the discovery of three sites where deposits of bronze fragments have been found, in the Roman cities of Pisaurum, Sentinum and Potentia. Each site yielded small bronze fragments and some tools, which lead us to suppose that these were sites of Late Antique foundries, where large bronze statues and other bronze objects were broken up to be remelted. The foundries were located on land previously occupied by taverns in the forum area or by residential quarters. This means that the urban plan of the cities had already been partially transformed, probably due to Christianisation and the construction of churches, which became the new community centres, to the detriment of the older areas of the forum. The rampant poverty and shortage of raw materials, especially metals, made foundries indispensable and, consequently, their widespread presence, even within the cities, probably became customary. Perhaps the numerous bronze fragments found in other centres of the region should also be interpreted in this same sense, as indications of foundries, even if the structures where the metal was worked have not been preserved. [ABSTRACT FROM AUTHOR]

This article provides a summary of the technological advances in the British iron industry. The major changes were the transition from the use of charcoal as fuel to mineral coal (or coke), first in blast furnace producing pig iron and then in producing (malleable) bar iron. Allied to this is the application of the reverberatory (or air) furnace first to foundry work and then to fining iron, ultimately in puddling furnaces. The ability to abandon charcoal as fuel in both sectors released the great expansion in iron production of the industrial revolution. Article History Received 27 September 2023; Accepted 20 December 2023 [ABSTRACT FROM AUTHOR]

Purpose: This paper presents application solutions related to the use of Fourth Industrial Revolution technologies in industry. The aim of the paper is including in a discussion about new trends in the development of information systems supporting monitoring, control and diagnostics of production processes. The objective was realised using the example of continuous production in steelworks. Design/methodology/approach: The aim of the paper was realized in theoretical and practical part of the paper. The empirical part of the was the form of a case study – approach to mathematical model for predicting the enthalpy of foundry ladles. Findings: The conclusion is simply: each industrial branch has to use own transformation path towards Industry 4.0. Practical implications: Prepared approaches - based on analysis of trends in data processing control system in the continues production - can be used to build algorithm of predictive model in its system. Research limitations/implications: The authors are aware of the limitations resulting from the excessive generality of the model, but they ensure that they will continue research on the implementation of Industry 4.0 technology in the metallurgical (metal) industry, with particular emphasis on the continuous course of manufacturing processes. Originality/value: The value of the paper are prepared approaches to mathematical model for predicting the enthalpy of foundry ladles. [ABSTRACT FROM AUTHOR]

Background & Aims: The correlation between silicosis and elevated susceptibility to lung cancer, chronic obstructive pulmonary disease, and autoimmune disorders is well-established. Hence, it is imperative to thoroughly analyze the potential health risks posed by exposure to crystalline silica within the foundry industry. Therefore, the present study aimed to evaluate the mortality rate associated with silicosis and lung cancer among workers in a foundry industry located in Urmia city in 2021. Materials & Methods: The concentration of crystalline silica in the air was determined using Fourier transform infrared spectroscopy (FTIR) in accordance with NIOSH 7602. Estimating the excess lifetime risk of mortality and rate of silicosis-related mortality was performed using Rice et al. and Mannetje et al. models. Results: The average concentration of crystalline silica in six occupational groups ranged from 0.029 to 0.064 mg.m-3. Among the six occupational groups studied, sand preparation workers were the most exposed to crystalline silica. According to the model of Mannetje et al., the cumulative exposure of 87% of people exposed to crystalline silica is in the range of 0 to 0.99, which indicates the death of one person per thousand people. Also, in this industry, the risk of dying from lung cancer was 15 per thousand people. Conclusion: The findings indicate that the average concentration of crystalline silica in all occupational groups exceeded the permissible occupational exposure limit of 0.025 mg.m-3 recommended by the Occupational Health Committee of Iran. Additionally, the estimated risk of death due to silicosis and lung cancer is also higher than the acceptable risk level. Therefore, the implementation of control measures against exposure to silica is highly recommended.

This study proves that lignin-based biopolymer materials can be employed as starting materials for the synthesis of novel casting binders that fulfill the current level of characteristics. The optimal concentration of the binder in the mixture was experimentally determined to be 5.8%–6.2%. It has been demonstrated in practice that the employment of ammonium salts as a technical lignosulfonate (TLS) modifier can result in the provision of cold (room temperature) curing of a mixture based on them. It was proposed to use as a technological additive that boosts the strength characteristics of a mixture of substances carboxymethyl cellulose (CMC). In a variety of adhesive materials, it is utilized as an active polymer base. The concentration limits for using CMC in the mixture are set at 0.15%–0.25%. To improve the moldability of the combination, it was suggested that kaolin clay be used as a plasticizing addition. The concentration limits for using a plasticizing additive are set at 3.5%–4.0%. The produced mixture was compared to the analog of the alpha-set method in a comparative analysis. It was discovered that the proposed composition is less expensive, more environmentally friendly, and enables the production of high-quality castings. In terms of physical, mechanical, and technological properties, the created composition of the cold curing mixture is not inferior to analogs from the alpha-set method. For the first time, a biopolymer-based binder system containing technical lignosulfonate with the addition of ammonium sulfate and carboxymethyl cellulose was used in the production of cast iron castings on the case of a cylinder casting weighing 18.3 kg from gray cast iron grade SCh20. Thus, it has been proved possible for the first time to replace phenol-based resin binders with products based on natural polymer combinations. For the first time, a cold-hardening mixture based on technological lignosulfonates has been developed without using hardeners made of very hazardous and cancer-causing hexavalent chromium compounds. But is achieved through a combination of specialized additives, including kaolin clay to ensure the mixture can be manufactured, ammonium sulfate to ensure the mixture cures, and carboxymethyl cellulose to enhance the strength properties of the binder composition. The study's importance stems from the substitution of biopolymer natural materials for costly and environmentally harmful binders based on phenolic resins. This development's execution serves as an illustration of how green technology can be used in the foundry sector. Reducing the amount of resin used in foundry manufacturing and substituting it with biopolymer binders based on technological lignosulfonates results in lower product costs as well as the preservation of the environment. Using lignin products judiciously can reduce environmental harm by using technical lignosulfonates, or compounds based on technical lignin. The combination is concentrated on businesses with single and small-scale manufacturing because it is presumable that this is merely the beginning of the investigation. This study confirms the viability of creating a cold-hardening combination based on technical lignosulfonates in practical applications and supports this with the castings produced, using the creation of a gray cast iron cylinder casting as an example.

Refractories are the basic material for the construction of the lining of a melting furnace used, among other things, in the foundry industry. The article describes a comparative study of the influence of the type of moulding on the quality of the finished refractory product. A method for making products from refractory materials was proposed and a test methodology was developed. The results, based on a classic study of the quality of these materials, confirm a strong influence on the quality of the materials obtained in terms of reduced porosity and homogeneity of pore size.

In the paper presented are results of a research on effectiveness of absorbing electromagnetic waves at frequency 2.45 GHz by unhardened sodium silicate base sands (SSBS) prepared of high-silica base sand and a PLA (Polylactide) 3D-prited (3DP) mould walls. Measurements of power loss of microwave radiation (P in) expressed by a total of absorbed power (P abs), output power (P out) and reflected power (P ref) were carried-out on a stand of semiautomatic microwave slot line for determining balance of microwave power emitted into selected multimaterial systems. Values of microwave power loss in the rectangular waveguide filled with unhardened moulding sands and prepared by fused deposition modelling (FDM) 5 mm polylactide (PLA) walls with grid infill density from 25% to c.a. 100% served for determining effectiveness of microwave heating. Balance of microwave power loss is of technological importance for microwave manufacture of high-quality casting sand moulds and cores in possibility of use 3D-printed mould tools and core boxes. It was found that apparent density of SSBS placed in a waveguide with PLA walls influences parameters of power output (P out) and power reflected (P ref). The PLA wall position and grid infill density were identified to have a limited effect on effectiveness of absorbing microwaves (P abs).

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Refractories are the basic material for the construction of the lining of a melting furnace used, among other things, in the foundry industry. The article describes a comparative study of the influence of the type of moulding on the quality of the finished refractory product. A method for making products from refractory materials was proposed and a test methodology was developed. The results, based on a classic study of the quality of these materials, confirm a strong influence on the quality of the materials obtained in terms of reduced porosity and homogeneity of pore size. [ABSTRACT FROM AUTHOR]

The application of structural optimisation is fast changing the thinking of Design Engineers. With the rapid development in high strength concrete and other materials which can resist higher loads, the task of reducing the weight of the structure can be addressed with ease. The present study is an application of topology optimisation of continuum structures. The design domain is modelled using first order basis splines and optimisation is performed using optimality criteria minimising strain energy as the objective function. A model pier cap is chosen with the standard dimensions of 3 feet x 9 in x 4 in. The size and location of openings are determined using topology optimisation and drawn in AutoCAD® software. The casting is done using concrete with different percentages of replacement of cement and fine aggregate. Cement is partially replaced using Alcofine and fine aggregate is partially replaced using waste foundry sand. The foundry sand is an industrial waste obtained from the foundry industry located at Balanagar, Hyderabad. Four specimen beams are cast and tested in the laboratory. Steel fibres are used to care for the tensile stresses produced within the beam. The analysis done here can be applied to any material other than concrete as well. The failure load is determined in the laboratory for each sample. The interpolation of failure load is done using python code and run on Anaconda Jupyter ® platform to determine the value of failure load for any percentage of replacement between 0 to 10%. [ABSTRACT FROM AUTHOR]

This study proves that lignin-based biopolymer materials can be employed as starting materials for the synthesis of novel casting binders that fulfill the current level of characteristics. The optimal concentration of the binder in the mixture was experimentally determined to be 5.8%-6.2%. It has been demonstrated in practice that the employment of ammonium salts as a technical lignosulfonate (TLS) modifier can result in the provision of cold (room temperature) curing of a mixture based on them. It was proposed to use as a technological additive that boosts the strength characteristics of a mixture of substances carboxymethyl cellulose (CMC). In a variety of adhesive materials, it is utilized as an active polymer base. The concentration limits for using CMC in the mixture are set at 0.15%-0.25%. To improve the moldability of the combination, it was suggested that kaolin clay be used as a plasticizing addition. The concentration limits for using a plasticizing additive are set at 3.5%-4.0%. The produced mixture was compared to the analog of the alpha-set method in a comparative analysis. It was discovered that the proposed composition is less expensive, more environmentally friendly, and enables the production of high-quality castings. In terms of physical, mechanical, and technological properties, the created composition of the cold curing mixture is not inferior to analogs from the alpha-set method. For the first time, a biopolymer-based binder system containing technical lignosulfonate with the addition of ammonium sulfate and carboxymethyl cellulose was used in the production of cast iron castings on the case of a cylinder casting weighing 18.3 kg from gray cast iron grade SCh20. Thus, it has been proved possible for the first time to replace phenol-based resin binders with products based on natural polymer combinations. For the first time, a cold-hardening mixture based on technological lignosulfonates has been developed without using hardeners made of very hazardous and cancer-causing hexavalent chromium compounds. But is achieved through a combination of specialized additives, including kaolin clay to ensure the mixture can be manufactured, ammonium sulfate to ensure the mixture cures, and carboxymethyl cellulose to enhance the strength properties of the binder composition. The study's importance stems from the substitution of biopolymer natural materials for costly and environmentally harmful binders based on phenolic resins. This development's execution serves as an illustration of how green technology can be used in the foundry sector. Reducing the amount of resin used in foundry manufacturing and substituting it with biopolymer binders based on technological lignosulfonates results in lower product costs as well as the preservation of the environment. Using lignin products judiciously can reduce environmental harm by using technical lignosulfonates, or compounds based on technical lignin. The combination is concentrated on businesses with single and small-scale manufacturing because it is presumable that this is merely the beginning of the investigation. This study confirms the viability of creating a coldhardening combination based on technical lignosulfonates in practical applications and supports this with the castings produced, using the creation of a gray cast iron cylinder casting as an example. [ABSTRACT FROM AUTHOR]

The requirements placed on the foundry industry are mainly related to the need to maintain an appropriate quality–price ratio of the product and to maintain an appropriate production regime that takes into account modern legal solutions related to environmental protection. This work is part of the trend of searching for new or previously unused materials from renewable sources in moulding sand technology. This article concerns the possibility of using barley malt in moulding material technology as a binding material. The presented work contains the results of research on the release of gases during casting, where high temperatures cause the decomposition of chemical substances. The tests confirmed that moulding sands with barley malt as a binder do not cause excessive emissions of harmful gaseous products when pouring moulds with liquid casting alloy. The volume of gases formed was smaller than that of commonly used moulding sands with other binders. The total volume of gases produced and the kinetics of their release indicate that casting in this type of moulding sand did not cause any technological inconvenience or casting defects of gaseous origin. This was confirmed by research involving obtaining iron castings in industrial conditions using barley malt as a binder in moulding sand technology, which were then subjected to visual assessment and roughness analysis.

Foundries, to the same extent today as in the past, represent one of the strategic branches of all industry. In fact, all aspects of modern life depend on the casting and production of brake discs, medical implants, marine engines, and even aircraft components like turbine blades. Foundries provide supplies to all sectors of modern industry, including automotive, aircraft, medicine, power generation, etc. The Slovak economy largely depends on the automotive industry for which casting is necessary. Cast components are used not only for engines, chassis, and drives but also in vehicle bodies. This article reports information on the current number of foundries in Slovakia, the number of produced casting tons and melting methods, the casting techniques in various foundries, and the types of cast metals. It considers the income of individual foundries, the impact of the economic situation, and assumptions regarding further development.

Molding sand mixtures used in the foundry industry consist of various sands (quartz sands, chromite sands, etc.) and additives such as bentonite. The optimum control of the processes involved in using the mixtures and in their regeneration after the casting requires an efficient in-line monitoring method that is not available today. We are investigating whether such a method can be based on electrical impedance spectroscopy (EIS). To establish a database, we have characterized various sand mixtures by EIS in the frequency range from 0.5 kHz to 1 MHz under laboratory conditions. Attempts at classifying the different molding sand mixtures by support vector machines (SVM) show encouraging results. Already high assignment accuracies (above 90%) could even be improved with suitable feature selection (sequential feature selection). At the same time, the standard uncertainty of the SVM results is low, i.e., data assigned to a class by the presented SVMs have a high probability of being assigned correctly. The application of EIS with subsequent evaluation by machine learning (machine-learning-enhanced EIS, MLEIS) in the field of bulk material monitoring in the foundry industry appears possible.

This paper presents the environmental impacts of reciprocating engine component (REC) made of cast iron and low-alloy steel in Finland using life cycle assessment (LCA). The study uses primary data provided by a machining shop in Finland covering cradle-to-gate with a functional unit of 1 tonne of REC. The assessment was carried out using CML-baseline, resulting in eleven impact categories emphasising global warming potential (GWP). The results show that the upstream process, including forging and foundry, to manufacture the material inputs contributes the highest among all impact categories, making up about 52–97% of the total impacts. For GWP, the total emission to manufacture 1 tonne REC is about 2926 kg CO2 eq. Sensitivity analysis indicates that material inputs of cast iron and low-alloy steel are the most critical parameters making process efficiency and technological advance prominent. This study highlights the importance of selecting suppliers, energy sources, and transportation modes. [ABSTRACT FROM AUTHOR]

In the paper presented are results of a research on effectiveness of absorbing electromagnetic waves at frequency 2.45 GHz by unhardened sodium silicate base sands (SSBS) prepared of high-silica base sand and a PLA (Polylactide) 3D-prited (3DP) mould walls. Measurements of power loss of microwave radiation (Pin) expressed by a total of absorbed power (Pabs), output power (Pout) and reflected power (Pref) were carried-out on a stand of semiautomatic microwave slot line for determining balance of microwave power emitted into selected multimaterial systems. Values of microwave power loss in the rectangular waveguide filled with unhardened moulding sands and prepared by fused deposition modelling (FDM) 5 mm polylactide (PLA) walls with grid infill density from 25% to c.a. 100% served for determining effectiveness of microwave heating. Balance of microwave power loss is of technological importance for microwave manufacture of highquality casting sand moulds and cores in possibility of use 3D-printed mould tools and core boxes. It was found that apparent density of SSBS placed in a waveguide with PLA walls influences parameters of power output (Pout) and power reflected (Pref). The PLA wall position and grid infill density were identified to have a limited effect on effectiveness of absorbing microwaves (Pabs). [ABSTRACT FROM AUTHOR]

The problems of establishing a new foundry in Kazakhstan utilizing Lost-foam casting technology are discussed in this article. The study’s main objectives are to determine the technical and financial viability of arranging such production in the country. Calculations of the manufacturing program were carried out as part of the study, and a financial- economic model of the project was developed. The research shows that establishing such a foundry is feasible, and the project may be recommended for execution.

Sustainable technologies play an important role in businesses by reducing negative environmental effects, avoiding depletion of natural resources whilst ensuring productivity. Zimbabwe is importing metal steel products that could be produced locally if local foundries adopt the rightful technologies. Most of Zimbabwean metal recyclers are using manual methods in the recycling process. The study looked at the negative effects of using manual production systems on the business performance of the Zimbabwean metal recycling industries. Qualitative and quantitative data collection techniques were adopted through the use of questionnaires and survey interviews. The researcher collected quantitative data through a questionnaire.77 out of 109 distributed questionnaires were returned and filled correctly by production personnel in the metal recycling industry. This translated to 70% response rate. Semi-structured interviews were conducted for the purposes of gathering qualitative data. Quantitative data revealed that metal recyclers are facing challenges of reduction in processing speeds, reduction in operation profits, poor product quality and high risk of getting injured due to the use of manual production methods. The study revealed that Zimbabwean metal recyclers are facing many challenges which to a greater extent are caused by their operation methods.

A new type of organobentonite foundry binder composed of a composite of bentonite (SN) and poly(acrylic acid) (PAA) was analyzed using thermal analysis (TG-DTG-DSC) and pyrolysis gas chromatography mass spectrometry (Py-GC/MS). The temperature range in which the composite retains its binding properties was identified using thermal analysis of the composite and its components. Results showed that the thermal decomposition process is complex and involves physicochemical transformations that are mainly reversible at temperatures in the ranges of 20–100 °C (related to evaporation of solvent water) and 100–230 °C (related to intermolecular dehydration). The decomposition of PAA chains occurs between 230 and 300 °C, while complete decomposition of PAA and formation of organic decomposition products takes place at 300–500 °C. Dehydroxylation of montmorillonite (MMT) in bentonite begins at about 500 °C, which leads to a drastic structural transformation. An endothermic effect associated with the remodeling of the mineral structure was observed on the DSC curve in the range of 500–750 °C. The produced SN/PAA composite was found to be thermostable during degradation in both oxidative and inert atmosphere, similar to the starting bentonite, and even maintained over a relatively higher and wider temperature range compared to organic binding materials used. At the given temperatures of 300 °C and 800 °C, only CO2 emissions occur from all the examined SN/PAA samples. There is no emission of compounds from the BTEX group. This means that the proposed binding material in the form of the MMT-PAA composite will not pose a threat to the environment and the workplace. [ABSTRACT FROM AUTHOR]

Green moulding sands containing special carbonaceous additives, which are the source of lustrous carbon (LC), are discussed in this paper. Five potential lustrous carbon carriers, i.e., two types of hard coal dust (No.1 and No.2), amorphous graphite (No.3) and two hydrocarbon resins (No.4 and No.5), were selected for tests as carbonaceous additives to conventional moulding sands. To better emphasize the differences in the additives used, reference green moulding sand (GMS1) was prepared and subjected to a wide range of basic tests focussed on technological parameters, such as permeability (Pw), friability (Fw), Dietert mouldability test (PD) and compactability (Z) and mechanical parameters, such as compressive strength (Rcw), tensile strength (Rmw), strength in the transformation zone (Rkw). The proposed comprehensive spectrum of tests was repeated on sands with five carbonaceous additives. The most important for the use of additives as carbon carriers was to interrelate the content of lustrous carbon (LC), loss on ignition (LOI) and the obtained results of mechanical and technological tests carried out on conventional moulding sands with the surface quality of iron castings. For this purpose, a series of iron castings was made in the prepared moulding sands and used for the assessment of surface quality based on a number of roughness parameters (Ra, Rz, Rp, Rq, Rv, Rlr, RSm). As a result of the studies it was found that the carbonaceous additives proposed for use help to obtain high-quality surfaces in iron castings. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Global warming is likely to affect certain groups such as workers in heat-producing industries. With limited research exploring such an important area, this study aimed to explore the heat stress vulnerability and adaptive strategies of indoor small-scale factory workers. Methods: This was a cross-sectional study and a mixed-method approach was used. The study setting was small-scale factory units. The quantitative component included environmental and biological monitoring from six units of steel rolling mills and foundry in the summer and winter seasons. The study was conducted during the period of November-2018 and May 2019. Heat stress was measured among workers using a portable Wet Bulb Globe Temperature (WBGT) meter. The physiological parameters of workers were also measured. The qualitative component included in-depth interviews of workers and supervisors from eleven units. Results: The maximum temperatures recorded at steel rolling mills and foundry crossed Occupational Safety and Health Administration (OSHA) threshold (27.5℃) in summer as well as winter. The mean WBGT at the steel rolling mill recorded 31.5℃. The physiological measurements of workers also crossed the threshold level for heart rate and oral temperature in steel rolling and foundry units. The units had mechanisms to dissipate heat but lack a temperature monitoring mechanism inside the units. The workers wore lighter or fewer clothes as an adaptive measure but uncomfortable PPEs in foundry units were avoided. Conclusion: Heat stress in small-scale industry units was found high and there is a high need to develop specific strategies for such vulnerably high heat-exposed groups.

The aims of this publication is to study the physical and chemical conditions of formation of self-hardening aluminum phosphate binders based on orthophosphoric acid and fine-grained aluminum powder, research of its chemical structure and properties of core mixtures for foundry production.The methods used in the work are: X-ray phase analysis on the Rigaku Ultima IV, differential thermogravimetric analysis on the STA 449 C. Orthophosphoric acid 85% concentration and finely dispersed aluminum powder were used as materials. Samples of core mixtures were made on the basis of quartz sand with an average particle size of 0.2 … 0.3 mm.As a result of the experiments, it was established that in the system of orthophosphoric acid and finely dispersed aluminum powder, a chemical interaction occurs at ambient temperature, which leads to the formation of a phosphate binder. It has been confirmed that it is aluminum orthophosphate in the form of berlinite, and it does not undergo phase transformations, namely it is thermally stable when heated from 20 to 1000 оС. A significant advantage for core mixtures in foundry production is that the chemical interaction in this system does not begin immediately after mixing the components, but after 5 … 10 min, which is explained by the presence of protective oxide or hydroxide films on the aluminum particles. This ensures the period of technological suitability of the core mixture, and subsequently ensures its self-hardening.In contrast to previously known aluminum phosphate binders, which required heating from 200 to 300 оС for their hardening, a self-hardening aluminum phosphate binders and the core mixture based on it were created for the first time.With the amount of 2 … 3% of orthophosphoric acid and 1 … 2% of aluminum powder, after 1 h the strength indicators of the mixture based on quartz sand exceed 1 MPa, which is sufficient for the production of foundry cores.

The problems of establishing a new foundry in Kazakhstan utilizing Lost-foam casting technology are discussed in this article. The study's main objectives are to determine the technical and financial viability of arranging such production in the country. Calculations of the manufacturing program were carried out as part of the study, and a financial-economic model of the project was developed. The research shows that establishing such a foundry is feasible, and the project may be recommended for execution. [ABSTRACT FROM AUTHOR]