Foundry

In an effort to reduce its impact on the environment, the construction sector is always looking for sustainable
substitutes for traditional building materials. The combined impacts of incorporating jute fibre into concrete and
using waste foundry sand (WFS) as a partial substitute for fine aggregate are examined in this study. WFS is a
byproduct of metal casting operations that presents environmental issues and disposal obstacles. But adding it to
concrete as an additive can have positive effects on the environment and the economy. To asses the compressive
strength and split tensile strength for 28,56 and 90 days.

Graphite is one of the main phases in the structure of most cast irons whose shape, morphology and distribution have a significant effect on the mechanical properties of cast irons. In this respect we can mention the improvement in tensile strength and impact strength of ductile iron ...

In this study, the production of thin wall austempered ductile iron, heat treated in the mold and in the presence of Ni and Mo was investigated. The base iron was melted in an induction furnace and treated at 1450°C by plunging and sandwich methods. Ductile irons were cast in two ...

Міністерство освіти і науки України Національний університет біоресурсів і природокористування України Механіко-технологічний факультет Науково-дослідний інститут техніки і технологій Кафедра сільськогосподарських машин та системотехніки імені академіка П. М. Василенка Представництво Польської академії наук в Києві ЗБІРНИК ТЕЗ ДОПОВІДЕЙ XIХ МІЖНАРОДНОЇ НАУКОВОЇ КОНФЕРЕНЦІЇ "Сучасні проблеми землеробської механіки" (17-19 жовтня 2018 року) присвяченої 120-й річниці з дня заснування кафедри сільськогосподарських машин та системотехніки імені академіка П. М. Василенка та 118-й річниці з дня народження академіка Петра Мефодійовича Василенка Київ-Голосієво 17-19 жовтня 2018 р.

h i g h l i g h t s Characterisation of waste foundry sand using XRD, TGA-DTG and SEM. Utilisation of waste foundry sand for natural fine aggregate replacement. Fresh and hardened properties of self-compacting concrete containing waste foundry sand. Water permeability and sorptivity using autoclam apparatus.

The aim of this study was the experimental tests of the mechanical properties and structure formation processes of sustainable ceramics from hazardous lead ore flotation waste, spent foundry sand, and natural red clay to produce sustainable ceramics. The lead was mined on a large scale from lead ores in the city of Adrianópolis, Brazil, for 58 years. The wastes from this activity bequeathed profound environmental and social impacts. The mechanical characteristics of twenty compositions of the ceramics were analyzed through the flexural resistance, water absorption, apparent density, and linear shrinkage; the study of the physicochemical processes of the ceramics' mineral composite transitions and structure formation during sintering at 900-1250°C was accomplished using XRD, SEM, EDS, AAS, and LAMMA methods. All ceramics presented flexural resistance (until 10.08 MPa) in comparison with the values established in the Brazilian national standards (> 1.5 MPa), with low water absorption and shrinkage. Ceramics with 7% of the flotation waste and 10% spent foundry sand, whose resistance reached from 3.7 to 10.1 MPa, showed the best mechanical properties. Leaching and solubility analyses by AAS method showed that there is no environmental jeopardy in using these compositions to produce sustainable ceramics.

Renewed interest in inorganic binders for sand molding has also intensified research on different forms of it. In this study, solid inorganic sodium silicate binder was tested with different additives to see how these affected the silica mold quality. The five additives used were: glucose, sucrose, boric acid, aluminum oxide and iron(III)oxide powders. The mold quality was assessed through tests like bending strength, tensile strength, hot distortion, wear resistance, gas evolution and collapsibility tests. In addition, SEM imaging was done on some select mold fracture samples. In the end, a casting trial was carried out followed by a surface roughness and defects analysis. A reduction in mold strength was noticed with glucose and boric acid, while collapsibility was improved by glucose, sucrose and boric acid additives. Casting trials have shown the best surface finish to be obtained with sucrose additive. All the casts in general showed some penetration; however, repeat casts have proven that altering some casting parameters could result in casts with excellent surface finish using solid silicates.

Foundry greensand waste is a by-product generated in large quantities from casting operations. In this study, Foundry Sand Wastes (FSW) were collected from three ferrous foundries. The samples were named Sample A, B and C. The samples were examined using an X-ray Diffractometer (XRD) to study the mineralogical phase of the FSW and X-ray Fluorescence (XRF) to determine the chemical composition of the FSW while a particle size distribution analyzer was used to determine the grain size distribution of the FSW. Scanning Electron Microscope was also used to determine the morphology of the samples. The silica sand in the mix was replaced by 50% FSW to produce concrete paver in the ratio of 1:1:2, 1:2:4 and 1:3:6. These ratios represent cement: silica sand + FSW: coarse aggregate. The ratio that produced the maximum compressive strength per concrete paver sample is the ratio 1:1:2 and this is similar to the split tensile strength test. The concrete paver samples were subjected to a compressive strength test and split tensile test. Quartz is the predominant mineral found in the FSW samples as revealed by XRF and XRD while the major constituents found in the three FSW samples are Silicon (Si), Iron (Fe), and Aluminium (Al). The trend of the compressive strength and split tensile strength results is consistent. Sample A compressive strength result at 28 days is 23 MPa which is below the acceptable value. Hence, Sample A was not recommended. However, samples B and C showed acceptable compressive strength results of 26MPa and 50MPa respectively at 28 days. Sample C showed the highest strength results for all the curing ages when compared with other samples. Beneficiation of the FSW that makes paving bricks wit hin acceptable toughness and durability values is recommended.

The aim of the present study was to evaluate the possible association between occurrence of soft tissue sarcomas in Verona (Italy) and residence near a steel foundry, whose emissions of dioxin-like compounds may be relevant. Exposure to total suspended particulate (TSP) emitted from the plant as estimated by ADMS-urban dispersion model was used as an indirect index of exposure to dioxin-like compounds. Verona municipality was divided in six subareas according to the decreasing levels of estimated TSP exposure, and soft tissue sarcomas cases were mapped according to residence at time of diagnosis. Standardized incidence ratios were computed. No statistically significant departures between observed and expected cases were detected as illustrated by trend-test results.

between the sand grains on drying and also provides the superior surface finish of intricate In manufacturing industry, the surface finish of the casting. The FRC provides a barrier to molten metal cast components is an important parameter to penetration to mold/core wall and to minimize assure quality and aesthetics. In sand casting surface defects i.e. metal penetration, process the surface finishing depends on the veining/fining, mold erosion, metal-mold reaction, properties of sand and other factors i.e. component carbon pick up and blow holes etc. [2-3]. The geometry, melt and pouring temperature, pouring application of FRC could improve overall casting speed, time and component section size [1]. quality through enhanced surface finish, reduced Mold or core coating is being extensively used in CO 2 fettling and scrap cost [4]. Nwaogu et al. [5] and green sand molding for the production of high concluded in their study that the refractory fillers in quality castings. The unavailability of proper sand sol-gel refractory coating have considerable effect grade and poor refractoriness of the mold and core on the casting surface finish by filling the pores surfaces confer the extensive use of Foundry between sand grains thus exhibiting fair thermal Refractory Coating (FRC), which covers the voids stability.

To produce low cost concrete by blending various ratios of fine aggregate and cement with used foundry sand and Pozzocrete to reduce disposal and pollution problems due to used foundry sand and Pozzocrete.Pozzocrete P60 is a processed quality assured fly ash, investigated for its use as a partial replacement for cement in concrete (1:1.48:3.21). The utilization of Pozzocrete P60 as cement replacement material in concrete or as additive in cement introduces many benefits from economical, technical and environmental points of view. The innovative use of used foundry sand in concrete formulations as a fine aggregate replacement material was tested as an alternative to traditional concrete. This paper presents the results of the concrete of mix proportion 1:1.48:3.21 in which cement is partially replaced with Pozzocrete P60 as 10% by weight of cement, and fine aggregate is partially replaced with used foundry sand as 10%, 30% and 50% by weight of fine aggregate. Five set of mixture proportions were made. First (A0) were standard mix (without Pozzocrete and used foundry) sand with regional fine aggregate (sand)and coarse aggregate and the second (B0) mix contained 10% Pozzocrete P60obtained from DIRK India Private Limited, Nasik, Maharashtra state. Other mixes (B1, B2, and B3) contained Pozzocrete P60 (10%)plus foundry sand (10%, 30%and 50%)respectively obtained fromferrous and non-ferrous metal casting industries.The compressive strength and water absorption has been obtained with partial replacement of Pozzocrete P60 with cement and foundry sand with fine

Se reporta la caracterizacion morfologica preliminar de un composite metalico base Al-Si, reforzado con β-SiC y consolidado por Compoforjado. Esta tecnologia es un hibrido entre los procesos de fundicion para composites metalicos particulados (CMRPs) y la forja semi-solida. Las propiedades comunes a dichos materiales, se alcanzan gracias a la microestructura globular, debido a la agitacion previa de la colada en estado semisolido, con una perfecta distribucion de las particulas de refuerzo. Posteriormente, es posible alcanzar una minima defectologia (i.e. porosidades), mediante la aplicacion de presiones de hasta 60MPa.

This paper describes and exercises a new design paradigm for cast components. The methodology integrates foundry process simulation, non-destructive evaluation (NDE), stress analysis and damage tolerance simulations into the design process. Foundry process simulation is used to predict an array of porosity-related anomalies. The probability of detection of these anomalies is investigated with a radiographic inspection simulation tool (XRSIM). The likelihood that the predicted array of anomalies will lead to a failure is determined by a fatigue crack growth simulation based on the extended finite element method and therefore does not require meshing nor remeshing as the cracks grow. With this approach, the casting modeling provides initial anomaly information, the stress analysis provides a value for the critical size of an anomaly and the NDE assessment provides a detectability measure. The combination of these tools allows for accept/reject criteria to be determined at the early design stage and enables damage tolerant design philosophies. The methodology is applied to the design of a cast monolithic door used on the Boeing 757 aircraft. Keywords Casting design and modeling AE Extended finite element method, XFEM AE Crack growth and damage tolerance analysis AE Non-destructive evaluation AE Industrial problems AE Micro-macro simulations 1 Introduction: cast airframes components and the regulatory design regime

Introduction: The present study investigated the effect of noise on blood pressure and heart rate of workers in an oil and gas industry in Khuzestan province. Methods: This descriptive-analytical study was conducted on 60 employees of one of the oil and gas industries who worked in administrative, warehouses, and operation units. A demographic questionnaire, a Beurer blood pressure monitor (BC16), and a sound level meter (TES1358) were used for data collection. Blood pressure and heart rate were measured before, during, and after the work. ANOVA and Paired Sample Test were used for data analysis in SPSS software. Results: Occupational exposure of administrative, warehouse, and operation unit workers to noise were 50-60, 85-75 and 95-85 dBA, and their heart rate was 79.38, 82.12, and 85.73 beats per minute (BPM), respectively. Before exposure to noise the mean heart rate of workers in the operation unit was 82.29±3.58 BPM and after exposure it was 85.73±1.92 BPM, and the difference was statistically significant (P-Value<0.001). The mean blood pressure of exposed to noise workers was significantly higher than that of nonexposed to noise workers (P-Value<0.001). The heart rate of operation unit workers was significantly higher, compared to other studied workers (P-Value<0.001). Conclusion: Considering the effect of noise on blood pressure and heart rate and the direct relationship between these parameters and cardiovascular diseases, it can be claimed that noise is one of the risk factors of cardiovascular diseases.

In this work, a comparative analysis of two iron bullets found in The Royal Ammunition Factory of Eugi in Navarra (Spain) was performed. Both bullets presented a spherical shape with a relatively good state of preservation, belonging to the last years of the factory production (1766-1850). Several techniques such as microhardness, X-ray fluorescence (XRF), light (LM) and scanning electron microscopy (SEM), optical mission spectroscopy (OES) and energy dispersive X-ray spectroscopy (EDX) analysis were used in order to identify the manufacturing process of the two bullets. The analyses of the microstructures carried out by LM and SEM showed that one bullet was composed of white cast iron with a pearlitic matrix, steadite and graphite; while the other was composed of grey cast iron with a pearlitic matrix, graphite and a low amount of steadite. The chemical analysis of the bullets carried out by OES indicated significant differences in the amount of silicon and phosphorous. The variati...

A study was carried out among iron foundry workers to assess occupational exposure to ambient respiratory dust in their work environment and rates of risk factors in each process by using Bayesian decision analysis (BDA) and AIHA (American Industrial Hygiene Association) exposure categorization guidelines. A total of 93 respirable dust samples were collected in various processes, including the molding, melting, shakeout, heat treatment, felting and finishing units of the foundries. The mean concentrations of respirable dust were 1.40±0.86 mg/m 3 in the molding process, 1.42±0.63 mg/m 3 in melting, 0.56±0.59 mg/m 3 in shakeouts, 1.63±0.85mg/m 3 in heat treatment, 2.17±0.61 mg/m 3 in felting, and 3.30±3.47 mg/m 3 in the finishing sections, respectively. The mean levels of respirable dust in the finishing process exceed the ACGIH standard (TLV 3 mg/m 3). The results of BDA show that the respirable dust exposures were in AIHA Category 4 for shakeouts (96.7% probability), felting (98.1% probability), and finishing (100% probability), respectively. The exposures belonged to category 3 for molding (52.8% probability), melting (79.4% probability) and heat treatment (40.3% probability), respectively. Therefore, it is required to have immediate control and safety adaptation by personal protective equipment of proper respiratory musk, engineer control, chemical analysis of respirable dust, exposure surveillance in order to prevent from being exposed to respirable dust among the foundry workers.

Abstrak : Kuningan merupakan paduan logam yang memiliki performa estetis yang tinggi sehinggabanyak dipakai untuk produk kran. Performa estetis ini menjadikan kran dari kuningan banyakdipakai di dunia perhotelan. Secara umum, produk kran dihasilkan melalui proses casting(pengecoran) yang dirancang melalui sejumlah simulasi guna menghasilkan produk dengankualitas tinggi. Pengecoran logam kuningan sering digunakan metode Low Pressure DieCasting (LPDC). Simulasi pengecoran adalah metode yang sangat baik untuk dapat melihatpenuangan logam cair pada cetakan, proses solidifikasi dan pendinginan, dan memprediksiletak cacat yang akan terjadi seperti shrinkage, porositas, inklusi, hole. Pada industripengecoran kran, banyak cacat pada produk hasil coran, yaitu: 8% produk bad, yang artinyaproduk tidak bisa digunakan atau harus di lebur ulang dan 24% produk modifikasi dengan cacatyang paling sering terjadi adalah “bocor” dan “hole” yang artinya produk mendapatkanperlakuan khusus karena terjadi ...

The Association of Hokkaido Interlocking Block Manufacturers has published a guide to structural designs of interlocking block pavement in Hokkaido on low volume road, with one-way daily traffic volumes of less than 250 truck passages. To investigate the adequacy of the structural design method, a test road was built as a part of the approach road to a landfill disposal site in Sapporo city. The traffic volume and the gross weight of trucks on the approach road were measured with a weigh bridge. Four different types of concrete block pavement structures were included in the test road. Deflection and rut depth measurements were made to evaluate the performance of the concrete block pavements. The total number of 50kN equivalent wheel load, was 1879 wheel passages for the test period. An equivalent elastic modulus of the concrete block layer which is the assumed modulus of a layer consisting of both the concrete block layer and sand bed was backcalculated from deflection data using a falling weight deflectometer (FWD). The estimated equivalent elastic modulus varied from 200 MPa to 570 MPa before service, and after. The loading of 1879 passages it varied from 330 MPa to 1010 Mpa. The moduli increased with the number of passages. The magnitude of the equivalent elastic modulus is corresponding to the elastic modulus of asphalt concrete at about 50°C. Therefore the load spreading capacity of concrete block layer, with sand bed is equivalent to the load spreading capacity of asphalt concrete at high temperatures.

RESUMEN: El proceso de fundición a la espuma perdida (FEP), es uno de los procesos de fundición preferidos en la actualidad cuando se trata de fabricar piezas de geometría intrincada, estrechas tolerancias dimensionales y buenos acabados superficiales. Cobral Ltda. es una empresa del sector metalmecánico situada en la ciudad de Medellín que desde el año 2000 se ha dedicado a la producción de piezas automotrices en fundición gris y nodular por el proceso FEP. Sin embargo, desde la puesta en marcha del proceso se obtuvieron altos porcentajes de rechazo, entre el 20% y el 50%. El estudio de las variables del proceso y su adecuado control en las diferentes etapas, permitió la minimización de los porcentajes de rechazo y un aumento en la productividad de la planta. Se describen las etapas del proceso FEP y algunos de los aspectos más relevantes de la optimización realizada.

Clay has an important role in making green sand casting mould beside water. Clay acts as binders, holding the sand grains together. Water is needed to activate the clay bond. Without the addition of water on clay, no strength would be achieved on sand mould, as the sand and clay would be just two dry materials. Bentonite clay was used in this study. Adequate clay content with suitable moisture in moulding sand is important for optimum strength and casting quality. Too little or too much clay will not give proper strength. Green compression strength is one of the mechanical properties to be considered for making green sand casting mould. The green compression strength of foundry sand is the maximum compressive strength that a mixture is capable of sustaining when prepared, rammed and tested according to standard procedure. For this study, test is conducted according to Foundry Sand Testing Equipment Operating Instructions from Ridsdale and Dietert. Result from this study indicates th...

Tailing sand is the residue from tin extraction, containing between 94% to 99.5% silica. It is abundant especially in Kinta Valley of state of Perak, Klang Valley of state of Selangor and certain areas in Johor, Negeri Sembilan and Pahang in Peninsular Malaysia. Many abandon tailing sand dump areas are easily to access due to the reason of transportation of tin and at present most of them have been covered by bushes even though there are efforts to convert the land for agriculture, industrial and housing estate. The worst scenario is issue of illegal activities of tailing sand mining including sand stealing. The purpose of this research is to investigate the mechanical properties of tailing sand as aggregate for making greensand casting mould. Five samples from Tronoh and Tanjung Tualang in Perak state; Batang Berjuntai in Selangor; Jemaluang in Johor and Gambang in Pahang were gathered. The experiments for this investigation are strictly obeying the American Foundrymen Society (AFS...

There is an increasing need to evaluate concentrations of nanoparticles in occupational settings due to their potential negative health effects. The Nanoparticle Respiratory Deposition (NRD) personal sampler was developed to collect nanoparticles separately from larger particles in the breathing zone of workers, while simultaneously providing a measure of respirable mass concentration. This study compared concentrations measured with the NRD sampler to those measured with a nano Micro Orifice Uniform-Deposit Impactor (nanoMOUDI) and respirable samplers in three workplaces. The NRD sampler performed well at two out of three locations, where over 90% of metal particles by mass were submicrometer particle size (a heavy vehicle machining and assembly facility and a shooting range). At the heavy vehicle facility, the mean metal mass concentration of particles collected on the diffusion stage of the NRD was 42.5 ± 10.0 µg/m3, within 5% of the nanoMOUDI concentration of 44.4 ± 7.4 µg/m3. A...

L'Equazione di Niman rappresenta un modello innovativo per la valutazione quantitativa del rischio in ambienti complessi e dinamici, come cantieri edili e aree industriali. Integrando variabili temporali e spaziali, offre una stima accurata del rischio totale (RT), superando i limiti degli approcci tradizionali basati su esperienze soggettive. Fondato su principi matematici quali la distribuzione normale, la probabilità bayesiana e l'analisi di grandi campioni di dati, il modello si distingue per la capacità di adattamento in tempo reale alle condizioni operative. L'Equazione di Niman eleva gli standard di sicurezza, trasformando l'analisi del rischio in un processo scientifico replicabile, basato su parametri oggettivi e verificabili. Questa metodologia promuove decisioni proattive e basate sui dati, rendendola una soluzione avanzata per la gestione del rischio.

The main aim of the foundry industries is to produce quality castings with no rejection. In addition, in the present era of global competition, manufacturing industries has bound to take the challenge that is demand for high quality product with reduced lead-time. However, with the diversity of greensand casting parameters, it results in varying effects on the quality. With sand being one of the most frequent cause of quality reject/rework, it is essential to understand the effect it has on the casting outcome. Taguchi's approach in quality states that the quality of a product is dependent on the input, he gured that the perfect time to eliminate differences in products is during the designing and manufacturing of products, he developed a strategy for quality that can be used in process. Therefore, it is important to understand the inputs in sand mould preparation. The focus of the research is on greensand moulding process. The casting defect is the most contributing factor to quality reject in most foundries. The sand moulding process is the most contributing factor to the formation scrap. The target in foundries is to achieve low casting defects at minimum cost. It is essential to select signi cant parameters that cause variation of quality characteristic of castings .data should be collected dictated by the chosen orthogonal array (OA) and parameter levels. With the collected at the analysis of variance (ANOVA) can be generated to determine the statistical importance of parameter and response graphs are plotted to determine the optimum setting of control parameter

Crucibles are indispensable for high-temperature industrial processes like metal melting and holding. Nigeria relies heavily on crucible imports, raising economic and supply chain vulnerability concerns. This study aimed to develop an indigenous method for producing graphite crucibles using raw materials sourced within Nigeria. Granite, kaolin clay, borosilicate glass, and silicon carbide were characterized and formulated in varying proportions with graphite powder. Samples were fabricated via dry pressing and sintered at 1200°C. X-ray fluorescence validated the chemical compositions, while X-ray diffraction and SEM-EDS confirmed the retention of graphite and homogenous dispersion of refractory oxide phases. Optimized compositions achieved hardness strength of over 4 MPa, and density of 2.48 g/cm3. Results demonstrate the feasibility of manufacturing graphite crucibles locally that meet industrial standards, utilizing readily available Nigerian raw materials. Further development promises strategic and economic benefits by reducing crucible import reliance and costs for vital Nigerian manufacturing industries. An Indigenous solution was established for critical crucible production by applying abundant domestic mineral resources.

The determination of heavy metals in blood is an important occupational environmental toxicology screening procedure. The aim of study was to determine the concentrations of Pb, Cd, Cr and Ni in blood samples of iron and steel foundry workplace exposed workers under routine clinical laboratory conditions. The method was employed for the quantitative determination of lead, cadmium, chromium and nickel in workplace environment particulate matter blood samples from iron and steel foundry workers and in unexposed controls. The results indicate that lead, chromium and nickel levels of the exposed workers are significantly higher those of the controls. Nickel Concentration (μg/L) in high P value=0.0306 and Chromium Concentration (μg/L) in P value=0.0295in worker population as compared to controls. Lead showed highest Absorption concentration in serum from particulate matter to Serum 47.3(μg/L). Absorption concentration of nickel in serum 16.5(μg/L) was lower than lead observed in worker&#...

Defects in cast metals remain a common problem in many areas of the foundry industry, particularly in the investment casting of large area, thin-walled components for aerospace applications. During previous research, the thermophysical properties, density and porosity of a fibre reinforced ceramic investment casting mould were determined using several experimental techniques. Without verification, these experimental results remain nothing more than educated guesswork. The purpose of this study is to verify previous results and to more fully characterise the ceramic mould material with complementary measurements. A commercially available computational fluid dynamic (CFD) simulation package, Flow-3D®, was used in conjunction with a full-scale Ni-superalloy (IN718) casting to assess the accuracy of these results. By placing thermocouples strategically across the mould thickness, temperature profiles were determined and compared directly to predicted profiles extracted from the simulati...

O uso de concretos de ultra alto desempenho (CUAD) tem se tornado cada vez mais comum em diversas soluções de Engenharia civil, principalmente pela sua composição de materiais que conferem propriedades de resistência e durabilidade que ultrapassam significativamente as classes dos concretos convencionais. Neste estudo buscou-se produzir CUAD usando areia fenólica de descarte de fundição (PFS). Foram ensaiadas cinco misturas de concreto. Uma CUAD de referência, chamada de REF, com 85% de cimento Portland branco (WPC) e 15% de sílica ativa (SF), como ligantes, e agregados em uma proporção de 36% de pó de quartzo e 84% de areia industrial. E quatro misturas eco amigáveis com adições minerais: RHA15, com 85% de WPC e 15% de RHA; FA15, com 85% de WPC e 15% de FA; RHA10-FA5, com 85% de WPC, 10% de RHA e 5% de FA; e RHA10-LF5, com 85% de WPC, 10% de RHA e 5% de LF. Com exceção da mistura REF, todas as demais misturas tiveram a adição de 15% de cal, tipo CH I, juntamente com agregados compostos por 36% de pó de quartzo e 84% de areia fenólica (PFS). A relação água/aglomerante adotada foi de 0,20 para todas as misturas. Os concretos foram submetidos a dois tipos de cura: úmida até a idade de ensaio e úmida combinada com cura térmica. Os concretos foram avaliados quanto à resistência à compressão axial e à microestrutura utilizando técnicas de análise termogravimétrica (TG/ DTG) e espectroscopia de infravermelho por transformada de Fourier (FTIR). Os resultados mostraram que todas as misturas atingiram níveis de resistência desejados para CUAD (150 Mpa). Até 28 dias, as misturas com RHA apresentaram maior resistência em comparação com as misturas com FA, independentemente do tipo de cura. Contudo, aos 91 dias, as misturas com FA e cura térmica foram mais resistentes que as misturas com RHA. Com os resultados obtidos percebe-se que a PFS pode ser usada como agregado de UHPC nos níveis de substituição testados. PALAVRAS-CHAVE CUAD; microestrutura; adições minerais; areia fenólica de fundição.

This paper is devoted to the memory of Professor Ljubomir Nedeljkovic (1933-2020), Head of the Department of Iron and Steel Metallurgy University of Belgrade, Serbia. Assessment of the melt quality is one of the most important casting process parameters, which allowed sound production of intricated cast parts. At the present time, various devices have been applied at foundry floors to control melt quality. Thermal analysis is one of them, widely used for melt quality control in ferrous and non-ferrous casting plants. During solidification, metal and alloys released latent heat, which magnitude is dependent on the type of phases that form during the solidification process. Plotting temperature versus time data during solidification provides useful information related to the actual solidification process. The applied technique is called thermal analysis, whereas the cooling curve is the name of such a plot. The main aim of this paper is to give a short overview of the present thermal ...

The phenolic urethane cold-box (PUCB) process was first introduced to the foundry industry in the late 1960s. Since then, it has become one of the most popular methods to make foundry purpose sand moulds and cores, utilized in the manufacturing of aluminium and cast iron cast components. The factors to be considered, affecting the general performance of a PUCB moulding mixture, are the temperature of sand, the moisture content, the mixing conditions, etc. Moreover, there are variable production parameters such as binder level, to improve certain properties of the mould and/or the core based on their specific area of application. These are mainly mechanical properties such as tensile or splitting strength. They have significant influences on the behaviour of the moulding material and are usually tested at room temperature. Although the production phases of the PUCB system are refined to a high extent today, the effect of binder content on the quality of the mould/core and the final casting should be supported by new approaches also in thermal sciences, interpreted in high-temperature environment. In this work, different PUCB mixtures were produced to evaluate the effect of various binder levels on the thermophysical properties of sand cores. Thermogravimetry, differential thermal analysis and a novel application of Fourier thermal analysis were used to study the decomposition processes of the PUCB mixture and to reveal the impact of binder level on the heat absorption (cooling) capacity of sand cores at temperatures relevant in the manufacturing of cast iron parts (1300 ± 10°C).

The most important advantage of foundry purpose moulding sand is that it can be reclaimed and reused through the casting manufacturing process. Supplying the foundry with a new source of material, sand reclamation brings along both environmental and economic advantages. Utilization of used sand can be considered as a common technological routine in the production of most types of chemically bound moulding materials. The epoxy-SO 2 process is prevalent in the processing of cast iron engine components worldwide. Based on its excellent properties, it is mainly suitable for producing internal sand cores with complex geometry. Even though reclaimed sand addition is an active and well-functioning feature in ferrous foundries, the scientific and thermophysical background of its effects on the casting process is yet to be explored. In this work, the thermal aspects of different reclaimed sand levels in the epoxy-SO 2 moulding system were examined. Thermogravimetry and differential thermal analysis of the epoxy-SO 2 and reclaimed sand in focus were carried out to obtain basic understandings about their high-temperature behaviour. A state-of-the-art Fourier thermal analysis method presented in a recent paper was used at temperatures corresponding to actual cast iron production (1300 ± 10°C), contrary to the previous tests at the typical temperature range of aluminium melt processing (660 ± 10°C). By the right of the method, the effects of reclaimed sand addition on the heat absorption (cooling) capacity of the epoxy-SO 2 moulding mixtures were investigated.

Now a days worthy class of regular sand is not readily existing, it is to be transported from a long distance. These resources are also draining very speedily. So there is a need to find substitute to natural sand. Regular sand takes millions of years for its establishment and is not easily. As a substitute to natural sand artificial sand is used as a partial replacement. The performance of concrete by partially switching the natural sand with foundry sand, which is a waste product from machine industries. In the present study the sand is replaced by foundry sand with different replacement levels of 12.5% , 25%, 37.5%, 50% for M40 and M50 grades of concrete and comparing results with normal concrete. Initially the basic tests on raw materials are performed following with mechanical properties, later considering the basic tests on raw materials the mix design for various grades of concrete is developed. RC beam of size 2000X250X150 mm is considered and by treating section as balanced section the reinforcement area is calculated for different replacement levels and for different grades, these RC beams are tested on a loading frame. The load vs deflection, span vs deflection, theoretical stress-strain curves are observed and tabulated and concluded that use of foundry sand as partial replacement satisfies the properties of concrete.