The main objective of the present study is enhanced of the sand moulding process through addressing the sand mould defects and failures, ultimately lead to improve production of the sand castings with well-defined of pattern profiles. The research aimed to reduce the cost and energy expenditure associated with the compaction time of the sand moulding process. Practical destructive tests were conducted to assess properties of the green sand moulds. Linear regression and multi-regression methods were employed to identify the key factors influencing the sand moulding process. The proposed experimental destructive tests and predicted regression methods facilitated measurement of the green sand properties and enabled evaluation of the effective moulding parameters, thereby enhancing the sand moulding process. Factorial design of experiments approach was employed to evaluate effect of parameters of water content and mixing time of the green sand compaction process on the mechanical properties of green sand mould namely the tensile strength, and compressive strength.
Hot deformation of metals is a widely used process to produce end products with the desired geometry and required mechanical properties. To properly design the hot forming process, it is necessary to examine how the tested material behaves during hot deformation. Model studies carried out to characterize the behaviour of materials in the hot deformation process can be roughly divided into physical and mathematical simulation techniques. The methodology proposed in this study highlights the possibility of creating rheological models for selected materials using methods of artificial intelligence, such as neuro-fuzzy systems. The main goal of the study is to examine the selected method of artificial intelligence to know how far it is possible to use this method in the development of a predictive model describing the flow of metals in the process of hot deformation. The test material was Inconel 718 alloy, which belongs to the family of austenitic nickel-based superalloys characterized by exceptionally high mechanical properties, physicochemical properties and creep resistance. This alloy is hardly deformable and requires proper understanding of the constitutive behaviour of the material under process conditions to directly enable the optimization of deformability and, indirectly, the development of effective shaping technologies that can guarantee obtaining products with the required microstructure and desired final mechanical properties. To be able to predict the behaviour of the material under non-experimentally tested conditions, a rheological model was developed using the selected method of artificial intelligence, i.e. the Adaptive Neuro-Fuzzy Inference System (ANFIS). The source data used in these studies comes from a material experiment involving compression of the tested alloy on a Gleeble 3800 thermo-mechanical simulator at temperatures of 900, 1000, 1050, 1100, 1150oC with the strain rates of 0.01 - 100 s-1 to a constant true strain value of 0.9. To assess the ability of the developed model to describe the behaviour of the examined alloy during hot deformation, the values of yield stress determined by the developed model (ANFIS) were compared with the results obtained experimentally. The obtained results may also support the numerical modelling of stress-strain curves.
Purpose: The useful data and information during the sand compaction process steps should be collected. Direct measurement methods of the sand mould properties during the actual moulding process are not adopted yet. Design/methodology/approach: In this work, a remote control system [1] have been integrated into a new flowability sensor [2]. Findings: To overcome the complexity of the tools and equipment that existed in laboratory, and in foundry. Research limitations/implications: In order to investigate, and control behavior of the moulding process of bentonite-bonded green sand process, the sensors have been equipped with the Bluetooth technology for a wireless transmission of the measured data to computers. Originality/value: This technique contributes to improve of the compaction process based on the non-destructive tests, enhances prediction of the optimum parameter conditions, and reduced the energy, and the compaction time consumed for the green sand moulding process.
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Currently on the mould-making machines market the companies like: DiSA, KUENKEL WAGNER, HAFLINGER, HEINRICH WAGNER SINTO, HUNTER, SAVELLI AND TECHNICAL play significant role. These companies are the manufacturers of various solutions in machines and instalations applied in foundry engineering. Automatic foundry machines for compaction of green sand have the major role in mechanisation and automation processes of making the mould. The concept of operation of automatic machines is based on the static and dynamic methods of compacting the green sand. The method which gains the importance is the compacting method by using the energy of the air pressure. It's the initial stage or the supporting process of compacting the green sand. However in the automatic mould making machines using this method it's essential to use the additional compaction of the mass in order to receive the final parameters of the form. In the constructional solutions of the machines there is the additional division which concerns the method of putting the sand into the mould box . This division distinquishes the transport of the sand with simultaneous compaction or the putting of the sand without the pre-compaction. As the solutions of the major manufacturers are often the subject for application in various foundries, the authors of the paper would like/have the confidence to present their own evaluation process confirmed by their own researches and independent analysis of the producers' solutions.
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Problems related to a gradual degradation of binding qualities of montmorillonite, the main component of foundry bentonites, are presented in the paper. This degradation is caused by high temperatures originated from liquid metal influencing moulding sands. Laboratory measurements of an active binding agent content in classic moulding sands prepared with two types of bentonite and subjected to a controlled heating to high temperatures – were performed. These laboratory examinations were compared to industrial tests, in which a temperature distribution was being determined in several places in the thickness of the casting ingot mould for 24 hours from the moment of pouring liquid metal. On the basis of the performed examinations, the method allowing to determine optimal additions in the rebounding process of the tested bentonites was developed.
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The article presents an experimental analysis of the effect of plastic grain size on the deformation of the pressed moulding during the process of punch thrust in a closed container. The effect of configuration and grain diameter on the flow of forces in the process of molding formation in the semi-liquid State. Test were performed by using specially prepared plasticine-based model material. The obtained test results are technological guidelines for manufacturing products from powders of the required grain size.
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The technological processes to obtain corundum granulate, i.e a raw material for isostatic pressing of protective armour tiles are presented. Two types of the granulate defects which are essential for protective abilities of the tiles are described: a) defective spherical granulate structure that leaves traces of defects in the form of hollow spaces, b) large radial gradient of internal friction manifesting in the density decrease with increasing of overall size of tiles. Improper granulate compaction leads to their individual sintering without creating sufficient strong bonds between granules. In fragments of tiles fired with the projectiles of calibre 12,7 mm and 14,7 mm fracture initiating defects as an effect of the projectile energy are shown. The pictures of the fragments surfaces show characteristic structures (splits). They give evidence of the absorption of large energies. The main mechanical ceramics parameters are attached, which characterize the tendencies linked to the enlargement of the overall size of the tiles.
PL
Przedstawiono procesy technologiczne otrzymywania granulatu korundowego - surowca wyjściowego w prasowaniu izostatytcznym płytek ochronnych do pancerzy. Zaprezentowano dwa typy defektów granulatu, które rzutują na właściwości ochronne płytek: a) zdefektowana struktura kulista granul pozostawiająca ślady defektów w postaci pustych przestrzeni, b) duży gradient promieniowy tarcia wewnętrznego, przejawiający się w zmniejszającej się gęstości wyprasek w funkcji zwiekszających się gabarytów prasowanych płytek. Niedoprasowanie niektórych granul prowadzi do ich indywidualnego spieczenia z rozerwaniem wiązań między sąsiednimi granulami. W odłamkach płytek ostrzelanych pociskami kalibru 12,7 mm i 14,5 mm zidentyfikowano makrowady inicjujące pękanie po wpływem energii pocisku. Zdjęcia powierzchni odłamków wykazują charakterystyczne struktury (odszczepienia) na tych powierzchniach, które świadczą o absorbcji znacznych energii. Przytoczono główne parametry mechaniczne ceramiki, charakteryzujące tendencje przy powiększaniu ogólnych gabarytów płytek.
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Wzrost zainteresowania żywnością wygodną wiąże się z osiągnięciem przez nią dobrej, akceptowalnej jakości. Na dobre postrzeganie produktów ma wpływ wiele czynników, w tym odpowiednie proporcje składników. Celem niniejszej pracy było określenie wpływu dodatku mleka na właściwości reologiczne mas lepkosprężystych (ciasta drożdżowe) oraz wpływu zmiany dodatku mleka na proces automatycznego formowania wyrobów dwurodnych. Zakres badawczy obejmował identyfikację parametrów reologicznych oraz określenie ich dopuszczalnych zmian tak, aby mógł zajść proces automatycznego formowania.
EN
Higher interesting of convenience food is dependent not only changes in life style but also because of achiving good, accepted quality. It is many reasons which influence on the acceptance, in between, is proper ratio of ingredients. The aim of the study was the influence determination of milk amount on the reheological properties of visco-elastic fluids and their possible changes due to properlly curry on automatic forming process.
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Z analizy najczęściej stosowanych technologii do wykonywania form odlewniczych wynika, że technologia formowania w masach bentonitowych na wilgotno jest najczęściej stosowaną, a uwzględniając niskie koszty produkcji oraz niską szkodliwość dla otoczenia, będzie w dalszym ciągu preferowana przy seryjnej produkcji odlewów. Dobre zagęszczenie formy, jako warunek konieczny do uzyskania dobrej jakości odlewów, można uzyskać wieloma metodami jednak jedną z najbardziej efektywnych uznano wstrzeliwanie z doprasowaniem. Ta znana od wielu lat technika zagęszczania, przy odpowiednim zaprojektowaniu urządzeń wykorzystujących jej zalety i eliminujących wady, może być w dalszym ciągu z powodzeniem wykorzystywana. [...]
EN
Most of the newly introduced technologies of creating mould for castings production is connected with chemical substancies left after the production process, which are very harmfull and hard to utilize. Therefore the green sand moulding will remain the most preferable technology, especially in the serial production of castings. The automatized process in this technology, apart from increasing the efficiency of work improves the working conditions to a Jarge degree. lt eliminates the noise and vibrations which are the most common causes of industrial diseases. This technology would change foundry into a friendly work place.The process of shoot press is considered to be the most effective for the automatization. Designing a machine that would eliminate the shortcomings of this process, and fully using its adventages has allowed to create an automatic mould machine. Such machine is succesfully working in a modernized automatic moulding line FA-87 in W-68 foundries in WSK Rzeszów. As far the technology is considered the shoot press is universal and can be widety used in foundrys making the process of mould creation fully automatic and eliminating the noise and vibrations.
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