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EN
During excavation of the cremation cemetery of urnfield culture in Legnica at Spokojna Street (Lower Silesia, Poland), dated to 1100-700 BC, the largest - so far in Poland – a collection of casting moulds from the Bronze Age was discovered: three moulds for axes casting made out of stone and five moulds for casting sickles, razors, spearhead and chisels, made out of clay. This archaeological find constituted fittings of foundrymen’s graves. In order to perform the complete analysis of moulds in respect of their application in the Bronze Age casting technology analytical methods, as well as, computer aided methods of technological processes were used. Macroscopic investigations were performed and the X-ray fluorescence spectrometry method was used to analyse the chemical composition and metal elements content in mould cavities. Moulds were subjected to three-dimensional scanning and due to the reverse engineering the geometry of castings produced in these moulds were obtained. The gathered data was used to perform design and research works by means of the MAGMA5 software. Various variants of the pouring process and alloys solidification in these archaeological moulds were simulated. The obtained results were utilised in the interpretation of the Bronze Age casting production in stone and clay moulds, with regard to their quality and possibility of casting defects occurrence being the result of these moulds construction. The reverse engineering, modelling and computer simulation allowed the analysis of moulds and castings. Investigations of casting moulds together with their digitalisation and reconstruction of casting technology, confirm the high advancement degree of production processes in the Bronze Age.
2
Content available Improvement of Artistic Cast Production System
EN
The paper presents the technology and organization of the artistic cast production. On the basis of the actual cast production system, the manufacturing process was shown, in particular sand–piece moulding, which is a very important process and a time-consuming part of the entire manufacture of the casts. The current state of the production process as well as the organization of the work and production technology were analysed with the use of methods and techniques of production improvement, the Lean Manufacturing concept and computer systems. The results of the analysis and studies were shown with use of schemes and graphs of the layout of the production resources, a flow chart of the production process, value stream mapping, and a costs table for the production and modernization of the moulding stage. The work has shown that there are possibilities to improve the artistic cast production system. This improvement leads to increased productivity, lower production costs of artistic casts and increased competitiveness of the foundry.
EN
The casting workshop in Grzybiany, in Lower Silesia (SW Poland) is a valuable source of knowledge on the development of casting techniques in the 7 – 6 centuries BC. Abundant evidence found on the archaeological site points to cast manufacturing by means of precision casting in ceramic moulds (lost-wax molding). The workshop is the biggest collection of moulds for bracelet, necklace and other smaller decorative artefacts in Poland. The aim of the work is to conduct the research of the moulds and casts with the view of performing a computer reconstruction of the casting moulds from the Bronze and Early Iron Age, based on the Grzybiany finds. As part of the work, both the microscopic structure and defectoscopic analyses of the casting moulds were performed. Chemical composition of the casts was tested using the X-ray fluorescence spectroscopy method. Based on these results and using computer modelling methods, a geometric visualisation was performed, which is the bases for preparing the visualisation of the process of pouring liquid metal into the moulds, reconstructing both the technology and the alloys used.
EN
The article deals with the effect on the quality of casting moulds (metal, bentonite mixture) on the structure of the alloy AlZn5,5MgCu and selected mechanical properties of the alloy. The effect of foundry moulds can significantly affect formation and range of crystal segregation and the subsequent thermal process of homogenization which has an influence on the final quality of the alloy. The research focuses on the formation and range of crystal segregation and its removal with homogenization annealing, in which the observed influence of individual factors influencing the diffusion process and quality of the aluminium alloy.
EN
The study presents the results of investigations on the hardening kinetics of modern pattern materials which, among others, include also epoxy resins. Tests were carried out using a new ultrasonic technique developed by the author of the present study. On the example of the EPO 999 resin, the run of the hardening process at temperatures of 10, 20 and 30°C was shown. This is the temperature range applied during production of foundry patterns. The time of the preliminary hardening amounted to 800 min at a temperature of 10°C , and to only 180 min at a temperature of 30°C . Using ultrasonic technique, the effect of temperature on the modulus of elasticity Ed of the examined resin was determined. The temperature has been observed to exert a linear effect on the value of the modulus Ed. When the resin pattern is preheated in the range of temperatures from 20 to 50°C , the value of the modulus Ed decreases by 30%. The drop in the value of the modulus Ed, as well as the resin hardness decreasing from 18 to 9,0 HB at the increasing temperature reduce the applicability of this material for patterns operating at high temperatures (moulding sands).
6
Content available remote Continuous temperature measurements on the pouring stand for casting moulds
EN
The results of temperature measurements of liquid iron alloys obtained by means of the pyrometer, PDR-1800 series, are presented in the paper. The measurements were performed in conditions determined by the kind of a pouring device. The results obtained for bottom-tap ladles were supplemented by laboratory measurements. These results allow explaining significant differences in the results of temperature measurements performed in pouring ladles by means of the pyrometric method and immersible thermocouple, which - in turn - improves assessment of metal thermal parameters in pouring devices.
EN
The monograph concerns the chosen aspects of the construction of the gating systems designed for ferrous metals in sand moulds. On the ground of the results of fluidity investigations: rod test and spiral test, there has been presented the method of determination the rheological parameters of liquid metals alloys. On the ground of the fluidity rod test it has been defined the curves of fluxion of metals alloys about different overheating degrees. The simulating investigations of pouring process of the perpendicular channels in the rod test has confirmed the thesis about the growth of boundary layer about the same parameters in channels about different diameters. It has been proved, that the parameters of metal boundary layer (supplementary rheological parameter and shape factor of boundary layer), appointed in definite conditions, can be applied to calculation of the thickness of metal boundary layer in the channels of gating system. There are two boundary layers: rheological and solidified. The thickness of the rheological boundary layer in channel of gating systems depends on: the value of supplementary rheological parameter appointed on the ground of the fluidity tests, the metallostatic pressure and length of the channel. The thickness of solidified boundary layer depends on the time and the thermophysical properties of the sand mould material. It has been affirmed, that in the first several seconds of pouring the sand moulds with the liquid ferrous metals, there is a violent fall of the flow ratio value in the channels of the gating systems. In this work there has been an attempt to prove that this phenomenon had been caused by the violent growth of the gas pressure and the large over-cooling of the metal boundary layer in the channels of gating system. On the basis of the hydraulic model of the heat flow, the method of determination heat dissipation coefficient in the sand moulds channels has been proposed. This coefficient allows to determinate the required overheating value for any element of gating system about definite dimensions. The simulation-experimental investigations of the ferrous metals flow through the furcated gating system permitted on ascertainment of occurrence the phenomenon of reflection the planes of metal stream in horizontal distributor channel and on explanation its influence on the process of filling niches of sand mould. On the ground of the analyses of the investigations results there have been presented the new proposals of calculation methods of metal flow efficiency coefficient through elements of gating systems.
8
Content available remote Development of pressure die casting and permanent-mould casting technologies
EN
Contribution deals with main directions of pressure die casting and permanent - mould casting. Research of mentioned technologies are made. Results of research are transferred into industrial practice. They are research of metal properties in interval of crystallization especially viscosity of liquid alloys, research of filtration, simulation of die filling and liquid metals solidifying. research of pressure die casting special methods, die materials, research of cooling system of permanent - moulds, thermograph y and radioscopy of permanent - moulds.
9
Content available remote Analiza dynamiki przenośnika form odlewniczych
PL
W referacie przedstawione są obliczenia przenośnika taśmowego form odlewniczych wykonane przy użyciu programu working model. Numeryczne rozwiązanie równań dynamiki umożliwia określenie obciążeń w elementach urządzenia.
EN
Dynamic analysis of discrete model of moulding form conveyor is presented. Numerical analysis of the model was carried out using Working Model system. Steady state and transient analysis of the conveyor was done.
10
Content available remote Przepływ siluminu AK12 w kanałach metalowych form odlewniczych
PL
Opisano podstawowe cechy przepływu siluminu AK12 w prostych kanałach form metalowych. Oceniono wpływ parametrów zalewania, a także zabiegu modyfikacji fosforem, na cechy przepływu.
EN
The basic attributes of the AK12 aluminum-silicon alloys flow in the straight channels of metal moulds have been presented. The influence on the flow attributes of both the pouring parameters and the modification treatment has been estimated.
11
PL
Opisano wpływ materiału i średnicy kanału formy na kinetykę oraz zakres temperatur krzepnięcia płynącej w nim strugi siluminu AK7. Określono temperaturę zatrzymania przepływu.
EN
The influence of both the channel material and the channel diameter on the solidification kinetic and the solidification range of the flowing stream of AK7-silumin has been described. The temperature of the flow stopping has been determined.
PL
W artykule przedstawiono nowoczesne tendencje w zakresie mechanizacji wykonywania form odlewniczych z syntetycznych, formierskich mas bentonitowych. Na tle tych tendencji przedstawiono analizę aktualnego stanu krajowego odlewnictwa oraz omówiono możliwości i kierunki modernizacji formierni.
EN
On the base of technical review of modern moulding machines and moulding lines, the present state of moulding plant mechanization in Polish Foundries has been analysed. The authors underline some aspects which are considerably influencing on the operation of moulding lines. Some data from chosen Polish Foundries have been presented.
PL
Podkreślając rozwój mechanizacji i automatyzacji procesów odlewniczych, wskazano na jego aktualne tendencje. Przedstawiono skrótowy przegląd współczesnych zagadnień mechanizacji i automatyzacji odlewniczych procesów technologicznych.
EN
Some aspects of mechanization and automatisation of chosen foundry processes have been described. The authors pay special attention to the role of mechanization and automatization of foundry process for improvement both casting quality and industrial safety. He described problems mainly have been concerned with green sand technology. Some remarks about the present situation of polish foudries in mentioned area have been given.
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