81 research outputs found
Rationalization of a Core Warehouse in the Casting Plant: A Case Study
The warehouse is an important factor in the manufacturing process. At present, there are constant demands for the more efficient and effective operation of warehouse systems. For this reason, the rationalization of existing warehouses and/or storage systems is one of the ways to achieve the previously set targets. The possibilities of rationalization are numerous in all segments of the observed system. The most suitable solutions for a particular warehouse will be found based on the nature of the observed problem and the available investment funds. The paper defines the place and the role of the warehouse in a casting plant. Besides, the current situation in the warehouse segment of casting plants is analyzed to identify problems. Finally, the development of different concepts of rationalization to relevant constraints is discussed. This approach has enabled us to solve the problem of the rationalization task and to produce the desired effects
Application of CAD/CAE/CAM Systems in Permanent-Mold Casting Improvement
This paper presents the application of CAD/CAE/CAM systems at the improvement of the manufacturing the flotation balls for grinding ore. Flotation balls need to satisfy the appropriate requirements in terms of dimensional, chemical, mechanical and physical properties. These properties are directly related to technology of ball manufacturing, in this case - permanent-mold casting technology. Software tolls from the group of CAD/CAE/CAM systems were used for designing the casting parts, casting and feeding systems, mold and simulation of permanent-mold casting process. Based on results of casting process simulation the casting process in real industrial conditions was realized. After the casting process, testing of casting parts has been performed. The testing gave satisfactory results, so the presented methodology, based on CAD/CAE/CAM systems, is acceptable for manufacturing program in foundry
Structural and mechanical properties of some aluminum-based binary alloys
The purpose of this study is to investigate structural and mechanical properties of some aluminum-based alloys. Microstructures of the Al-Sn and Al-Zn binary alloys were examined using optic microscopy. The mechanical properties - Vickers hardness and micro hardness tests were investigated according to standard procedure
Tri nova posmatranja debelokljune Äigre Sterna nilotica
Gull-billed Tern Sterna nilotica represent irregular passage bird of Serbia. During the 2010 this species was recorded 3 times ā on 29th April, 17th July and 4th August respectively. In all occasion one adult bird was observed feeding or resting during shorter or longer period of times. On all localites Gull-billed Tern was not recorded in the past. These sites are waster water lakes of sugar plant āKovaÄicaā, waste ponds between the town PanÄevo and village StarÄevo and Special nature reserve āZasavicaā
Phase diagram investigation and characterization of alloys in Bi-Ga10Sb90 section of Ga-Bi-Sb system
The results of phase equilibria investigation and characterization of the alloys in the Bi-Ga10Sb90 section of Ga-Bi-Sb system are presented in this paper. Phase diagram of the mentioned section has been calculated according to CALPHAD model, using Pandat software. In the frame of alloys characterization, structural, mechanical and electrical characteristics were determined using SEM-EDX analysis, microhardness and electroconductivity measurements
Thermal characterization of the InāSnāZn eutectic alloy
Thermal properties, including melting temperature, latent heat of melting, specific heat capacity and thermal conductivity, of a low-melting InāSnāZn eutectic alloy were investigated in this work. The InāSnāZn eutectic alloy with nominal composition 52.7In-44.9Sn-2.4Zn (at.%) was prepared by the melting of pure metals under an argon atmosphere. The conducted assessment consisted of both theoretical and experimental approaches. Differential scanning calorimetry (DSC) was used for the measurement of melting temperature and latent heat, and the obtained results were compared with the results of thermodynamic calculations. The measured melting temperature and the latent heat of melting for the InāSnāZn eutectic alloy are 106.5Ā±0.1 Ā°C and 28.3Ā±0.1 Jg-1, respectively. Thermal diffusivity and thermal conductivity of the InāSnāZn eutectic alloy were studied by the xenon-flash method. The determined thermal conductivity of the investigated eutectic alloy at 25 Ā°C is 42.2Ā±3.4 Wm-1K-1. Apart from providing insight into the possibility for application of the investigated alloy as the metallic phase-change material, the obtained values of thermal properties can also be utilized as input parameters for various simulation processes such as casting and soldering.Djordje Drobnjak - Memorial Issu
Mineralogical Transformations in Copper Concentrate Roasting in Fluo-Solid Reactor
This work presents the results of investigation process of copper concentrate roasting in fluo-solid reactor with the aim of studying a transformation degree of primary ore minerals under various technological parameters. Input material (charge) and roasting products (calcine) were investigated by x-ray diffraction, ore microscopy and chemical analysis. The investigation results have shown that reaction of mineral transformation are not completed, i.e. they are developed only partially (12 - 22%) what is a consequence of insufficient long heating, unsuitable temperature or unfilled other parameters as well as non-uniform grain size
EFFECT OF PARTICLE SHAPE AND SIZE OF COPPER POWDERS ON THE PROPERTIES OF SINTERED PARTS
The particle shape and size of the starting powders represent the most important physical properties, on which the quality of the compacts and final sintered products depends. Two types of powder were analyzed in the paper - electrolytic copper powder with a dendritic particle shape and water-atomized copper powder with an irregular particle shape. The starting powders were sieved through a sieve system with openings of 45 μm, 80 μm, and 120 μm. The characterization of the obtained fractions of both powders was performed by determining the shape and dimensions of the particles using SEM microscopy in combination with ImageJ software, and the apparent density and flow rate were determined using the Hall flowmeter funnel. Pressing of each powder fraction was done using a pressure of 600 MPa. The compacts were further sintered at 1000°C for 2 hours to obtain the final sintered parts. After sintering, their density, hardness, and electrical conductivity were determined and their microstructure was analyzed. The results indicate a great influence of the characteristics of the starting powders on the properties of the final parts obtained by the powder metallurgy route. The particle shape of the powders had a more pronounced influence compared to the particle size
The Effect of Copper Content in the Matte on the Distribution Coefficients Between the Slag and the Matte for Certain Elements in the Sulphide Copper Concentrate Smelting Process
This paper presents the results of investigating the dependence of distribution coefficient LS/MMe
for: Cu, Zn, Pb, Sb, As, Ni, Ag, Au and Bi, between the slag and the matte, on the copper content in matte. The research was conducted under industrial conditions of copper concentrate smelting, in the reverberatory furnace in the copper smelter in Bor, Serbia. It was found that with the increase of the copper content in the matte, distribution coefficient between slag and matte for Cu, Zn and Pb increases, for Ag and Se decreases, while for Ni, As and Sb has an insignificant change. Au and Bi are almost entirely concentrated in the matte
Phase equilibria investigation and characterization of the Au-In-Sb system
The Au-In-Sb system is of great interest recently, because its alloys belong to the group of potential lead-free solder materials to be used in electronics, while as a part of Au-ln-Sb-Te system, it presents a suitable phase change material in optical recording media. The results of phase equilibria investigation and characterization of the alloys in the AuIn-Sb section of the Au-In-Sb system are presented in this paper. The investigations were performed using different experimental methods - thermal analysis, optical microscopy and SEM-EDX, hardness and electrical conductivity measurements, and also, using ThermoCalc software based on adequate thermodynamic calculation
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