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PL
Zbadano przydatność polilaktydu (PLA) jako spoiwa do wielokrotnego stosowania do mas formierskich wykorzystywanych w procesach odlewniczych. PLA otrzymano z dużą wydajnością (71%) przez polikondensację laktydu. Masy formierskie z 2-proc. zawartością spoiwa uzyskano w wyniku odparowania chloroformowego roztworu PLA. Zbadano wytrzymałość na rozciąganie mas formierskich po ich wielokrotnym zawracaniu. Masy formierskie z 2-proc. zawartością PLA jako spoiwem, stapiane w wysokiej temp. 325°C można było zawracać nawet 13-krotnie, otrzymując masy charakteryzujące się dobrą jakością.
EN
Polylactide (PLA) was used as a binder for recycled molding sands in foundry processes. PLA was produced by lactide polycondensation with a high efficiency (71%). The molding sands with 2% binder content were prepd. by evaporating the solvent from CHCl3 soln. of PLA. The PLA-contg. molding sands cured at 325°C were successfully recycled up to 13 times.
EN
The paper presents the results of preliminary research on the application of olivine moulding sands with hydrated sodium silicate containing 1.5 % wt. of binder to perform ecological casting cores in hot-box technology using a semi-automatic core shooter. The following parameters were used in the process of core shooting: initial shot pressure of 6 bar, shot time 3 s, the temperature of the core-box: 200, 250 and 300°C and the core curing time: 30, 60, 90, 120 and 150 s. The matrix of the moulding mixture was olivine sand, and the binder of the sandmix was commercial, unmodified hydrated sodium silicate with molar module SiO2/Na2O of 2.5. In one shot of the automatic core-shooter were formed three longitudinal specimens (cores) with a dimensions 22.2×22.2×180 mm. The samples obtained in this way were subjected to the assessment of the influence of the shooting parameters, i.e. shooting time, temperature and curing time in core-box, using the following criteria: core box fill rate, mechanical strength to bending RgU, apparent density, compaction degree and susceptibility to friability of sand grains after hardening. The results of trials on the use of olivine moulding sands with hydrated sodium silicate (olivine SSBS) in the process of core shooting made it possible to determine the conditions for further research on the improvement of inorganic hot-box process technology aimed at: reduction of the heating temperature and the curing time. It was found that correlation between the parameters of the shooting process and the bending strength of olivine moulding sands with sodium silicate is observed.
EN
The paper presents the preliminary results of research on determining the possibilities of using available on the market commercial gypsum kinds as a binder for foundry moulding and core sandmixes. Construction gypsum and plaster gypsum, finishing coat and jewelry casting gypsum were tested. Elemental composition of gypsum kinds were carried out using a scanning electron microscope (SEM) with EDS/EDX probe, their crystal structure and phase composition was determined by analyzing the results of X-ray diffraction measurements (XRD) and thermogravimetric studies (TG-DTA). Evaluation of the mechanical properties of selected materials was carried out at the tensile strength test of the dog-bone samples after initial hardening of gypsum mortar at 25°C for 5 h and drying at 110°C for 24 hours. The impact of the properties of the used commercial gypsum kinds on the possibility of their use as a valuable binders in the manufacture of the foundry sandmixes for moulds and cores was evaluated. Construction gypsum and finishing coat have the highest tensile strength. Plaster gypsum and finishing coat have the longest setting time. In all tested types of gypsum, the initial water loss during heating occurs at a temperature of about 200°C. The lowest valuable properties as a binder for sand moulding mixtures has jewelry casting gypsum mass.
EN
The intercalation into interlayer spaces of montmorillonite (MMT), obtained from natural calcium bentonite, was investigated. Modification of MMT was performed by the poly(acrylic acid-co-maleic acid) sodium salt (co-MA/AA). Efficiency of modification of MMT by sodium salt co-MA/AA was assessed by the infrared spectroscopic methods (FTIR), X-ray diffraction method (XRD) and spectrophotometry UV-Vis. It was found, that MMT can be relatively simply modified with omitting the preliminary organofilisation – by introducing hydrogel chains of maleic acid-acrylic acid copolymer in a form of sodium salt into interlayer galleries. A successful intercalation by sodium salt of the above mentioned copolymer was confirmed by the powder X-ray diffraction (shifting the reflex (001) originated from the montmorillonite phase indicating an increase of interlayer distances) as well as by the infrared spectroscopy (occurring of vibrations characteristic for the introduced organic macromolecules). The performed modification causes an increase of the ion exchange ability which allows to assume that the developed hybrid composite: MMT-/maleic acid-acrylic acid copolymer (MMT-co- MA/AA) can find the application as a binding material in the moulding sands technology. In addition, modified montmorillonites indicate an increased ability for ion exchanges at higher temperatures (TG-DTG, UV-Vis). MMT modified by sodium salt of maleic acid-acrylic acid copolymer indicates a significant shifting of the loss of the ion exchange ability in the direction of the higher temperature range (500–700°C).
EN
Experimental and industrial research of the technological process during the year 2017, including planning, is presented in this paper. That research was conducted in the new Foundry of new Ferronickel in Drenas, which is in the village of Cikatove, Drenas, the Republic of Kosovo. According to initial calculations, an amount of ore which would enter the process was determined, however the anticipated amount was different from the one used during the process. The same applies to fuel. Difference between the planned and the actual amount of ore used during the year 2017 resulted from the percentage of Ni in the amount of ore used in the foundry, demand for an Fe-Ni ferroalloy etc. The technological process in the foundry serves the purpose of processing ore of ironnickel with a high percentage of Ni in its composition. The material balance of the technological process in the new Foundry of new Ferronickel in Drenas, presented in this paper, is based on experimental and industrial data of the technological process acquired in the foundry. The material balance includes the technological process starting from calculation of the amount of ore and fuel, both making up the load for the rotary kiln. Additional contributors to the material balance are calculation of the amount of: fuel, which impacts the increase of temperature in rotary kilns, charge for the electric furnaces, metal and slags from the electric furnaces, metal and slags from the refining process (convertors) and mathematical calculation of the final product which is the ferroalloy of Fe-Ni. While preparing the material balance we have noticed greater acquisition of Ni than planned. The greater amount of Ni was produced by a smaller amount of ore than originally planned.
EN
This paper presents initial findings from research into the possibility of using gypsum binders in quartz moulding sand that could be used in the production of casting moulds and cores. For the purposes of the research two commercial types of gypsum were used as binders: building gypsum and gypsum putty. Dry components of moulding sand i.e. medium quartz sand and gypsum were mixed in proportion of 89/11 parts by weight. In order to achieve bonding properties for the binders, 5 parts by weight of water was added to the mixture of dry components. After 24 hours of adding water and mixing all the components, the moulding sand, naturally hardened, was subjected to high temperature. The moulding sand thus produced, i.e. with cheap and environmentally-friendly gypsum binders, was eventually analysed after heating (at temperatures of 300oC, 650oC and 950oC) and cooling in order to determine changes in the following parameters: LOI – loss on ignition, chemical composition and pH. Moreover, investigated were bonding bridges, before and after the moulding sand was roasted. The research results revealed differences in the structure of bonding bridges and the occurrence of automatic adhesive destruction for both types of gypsum binders. For two types of moulding sands under the investigation of the LOI exceeded 2.59wt.% (with building gypsum) or 2.84wt.% (with putty gypsum) and pH increased to ca. 12 as a result of increasing roasting temperature from 300oC to 650oC. Next, roasting at 950oC decrease value of LOI in both types of moulding sands. Moulding sand with builoding gypsum roasted at 950oC revealed a return to the value of pH parameter measured prior to annealing.
9
Content available remote ITM Polska w hołdzie dla innowacyjności 6-9 czerwca 2017 roku
PL
Innowacyjność, dynamika, promocja nowości i nieszablonowych rozwiązań to wartości, które targom poznańskim przyświecają od blisko 100 lat. Były istotne w 1921 roku, gdy Międzynarodowe Targi Poznańskie rozpoczynały swoją drogę i są ważne dziś, w przededniu największych targów dedykowanych branży przemysłowej - ITM Polska.
10
PL
W roku 2014 zakończono prace badawcze nad opracowaniem technologii produkcji innowacyjnych, piankowych filtrów ceramiczno-węglowych do filtracji ciekłych stopów metali, finansowane przez NCBiR ze środków programu InnoTech. Partia badawcza filtrów wykonanych wg tej technologii została sprawdzona w praktyce w krajowych odlewniach staliwa i żeliwa. Próby wypadły pomyślnie i odlewnie zadeklarowały chęć zakupu nowoopracowanych filtrów do bieżącej produkcji odlewów. Dla firmy „Ferro-Term” Sp. z o.o. było to bodźcem do rozpoczęcia prac projektowych nad prototypową linią do seryjnej produkcji tych filtrów. Równocześnie, wraz z konsorcjum naukowym, w którego skład weszli współtwórcy technologii, tj. Instytut Ceramiki i Materiałów Budowlanych, Oddział Materiałów Ogniotrwałych w Gliwicach, Instytut Chemicznej Przeróbki Węgla w Zabrzu i Instytut Odlewnictwa w Krakowie, podjęto udaną próbę pozyskania części środków na niezbędne dostosowanie opracowanej technologii ze skali półtechnicznej na przemysłową z Programu Operacyjnego Inteligentny Rozwój. W artykule przedstawiono informację o postępie badań objętych harmonogramem realizowanego projektu.
EN
In 2014 research works aimed at developing a technology of production of innovative foam ceramic-carbon filters for liquid metal alloy filtration were completed. They were financed by the National Centre for Research and Development from the funds of InnoTech programme. The testing batch of filters made according to this technology was tested in practice at domestic cast iron and steel foundries. The trials were successful and the foundries declared their intention to purchase the newly-developed filters for the current production of casts. This provided Ferro-Term with an incentive to start project works on a prototype line for the batch production of these filters. At the same time, together with the scientific consortium, composed of the technology co-authors, i.e. Institute of Ceramics and Building Materials, Refractory Materials Division in Gliwice, Institute for Chemical Processing of Coal in Zabrze and Foundry Research Institute in Cracow, the authors undertook a successful attempt to obtain a part of the funds for necessary adjustment of the developed technology from the half-technical to industrial scale from Smart Growth Operational Programme. In this article information about progress in project scheduled researches was presented.
EN
This paper discusses the impact of high temperatures (up to 900°C) on molding and core sand with inorganic binders selected from among the group of unmodified grades of hydrated sodium silicate (water-glass). Molding sands with medium quartz sand were made under laboratory conditions and compacted at the different energy inputs necessary for obtaining various apparent densities (ϱ0). Due to the different composition and apparent density of molding mixtures hardened via microwaves at a frequency of 2.45 GHz, it was possible to assess their deformation (L) at a high temperature above the binder’s eutectic temperature. For this purpose, an apparatus for hot distortion tests was used whose construction and equipment allows us to measure the thermoplastic deformations in molding sand in many aspects; i.e., in its time of annealing. The article proposes new possibilities of interpreting the hot distortion phenomena in comparative studies of molding materials and mixtures. The application of this new measurement method revealed the differences between molding mixtures made with five inorganic binders with a molar module ranging from 2.0 to 3.4 and apparent density ranging from 1.34 to 1.57 g/cm3. It was established that distortions under the influence of high temperatures last the longest in molding sand with a binder with the highest molar module (3.4). Research also revealed that the density of molding sand is significant for increasing/decreasing the rate of thermoplastic deformations following the heating of samples only if the molding sand includes binders with a molar module of between 3.0 to 3.4. For molding sand with binders with molar modules from 2.0 to 2.5, it was established that this is excessively susceptible to thermoplastic deformation.
EN
Moulding sands containing sodium silicate (water-glass) belong to the group of porous mixture with low resistance to increased humidity. Thanks to hydrophilic properties of hardened or even overheated binder, possible is application of effective methods of hydrous reclamation consisting in its secondary hydration. For the same reason (hydrophilia of the binder), moulds and foundry cores made of high-silica moulding sands with sodium silicate are susceptible to the action of components of atmospheric air, including the contained steam. This paper presents results of a research on the effect of (relative) humidity on mechanical and technological properties of microwave-hardened moulding mixtures. Specimens of the moulding sand containing 1.5 wt% of sodium water-glass with module 2.5 were subjected, in a laboratory climatic chamber, to long-term action of steam contained in the chamber atmosphere. Concentration of water in atmospheric air was stabilized for 28 days (672 h) according to the relative humidity parameter that was ca. 40%, 60% and 80% at constant temperature 20 °C. In three cycles of the examinations, the specimens were taken out from the chamber every 7 days (168 h) and their mechanical and technological parameters were determined. It was found on the grounds of laboratory measurements that moulds and cores hardened with microwaves are susceptible to action of atmospheric air and presence of water (as steam) intensifies action of the air components on glassy film of sodium silicate. Microwave-hardened moulding sands containing sodium silicate may be stored on a long-term basis in strictly determined atmospheric conditions only, at reduced humidity. In spite of a negative effect of steam contained in the air, the examined moulding mixtures maintain a part of their mechanical and technological properties, so the moulds and foundry cores stored in specified, controlled conditions could be still used in manufacture.
EN
The ceaseless progress of nanotechnology, observed in the last years, causes that nanomaterials are more and more often applied in several fields of industry, technique and medicine. E.g. silver nanoparticles are used in biomedicine for disinfection and polymer nanoparticles allow insulin transportation in pharmacology. New generation materials containing nanoparticles are also used in the chemical industry (their participation in the commercial market equals app. 53 %). Nanomaterials are used in electronics, among others for semiconductors production (e.g. for producing nanoink Ag, which conducts electric current). Nanomaterials, due to their special properties, are also used in the foundry industry in metallurgy (e.g. metal alloys with nanocrystalline precipitates), as well as in investment casting and in moulding and core sand technologies. Nanoparticles and containing them composites are applied in several technologies including foundry practice, automotive industry, medicine, dentistry etc. it is expected that their role and market share will be successively growing.
EN
The aim of this study is to design and implement a computer system, which will allow the semantic cataloging and data retrieval in the field of cast iron processing. The intention is to let the system architecture allow for consideration of data on various processing techniques based on the information available or searched by a potential user. This is achieved by separating the system code from the knowledge of the processing operations or from the chemical composition of the material being processed. This is made possible by the creation and subsequent use of formal knowledge representation in the form of ontology. So, any use of the system is associated with the use of ontologies, either as an aid for the cataloging of new data, or as an indication of restrictions imposed on the data which draw user attention. The use of formal knowledge representation also allows consideration of semantic meaning, a consequence of which may be, for example, returning all elements in subclasses of the searched process class or material grade.
EN
This article presents the methodology for exploratory analysis of data from microstructural studies of compacted graphite iron to gain knowledge about the factors favouring the formation of ausferrite. The studies led to the development of rules to evaluate the content of ausferrite based on the chemical composition. Data mining methods have been used to generate regression models such as boosted trees, random forest, and piecewise regression models. The development of a stepwise regression modelling process on the iteratively limited sets enabled, on the one hand, the improvement of forecasting precision and, on the other, acquisition of deeper knowledge about the ausferrite formation. Repeated examination of the significance of the effect of various factors in different regression models has allowed identification of the most important variables influencing the ausferrite content in different ranges of the parameters variability.
16
Content available Odlewnictwo w literaturze antycznej
PL
W artykule zasygnalizowano obecność w literaturze świata antycznego wielu wzmianek odnoszących się do odlewnictwa. Ich analiza pozwala wzbogacić wiedzę o początkach i historii rozwoju odlewnictwa – jednej z najstarszych technicznych dziedzin działalności człowieka, odgrywającego w starożytności niezwykle istotną rolę i od niepamiętnych czasów określanego mianem sztuka. Przytoczono i omówiono wzmianki wskazujące, że w starożytności metale i umiejętność ich obróbki i odlewania uważane były za dar Boga czy bogów, opisujące początki i znaczenie odlewnictwa w zamierzchłych czasach, rozwój technologii wykonywania odlewów, a także wymieniające niektóre dzieła mistrzów sztuki odlewniczej świata starożytnego.
EN
The paper indicates the existence of many references to casting in the ancient literature. Their analysis allows one to enrich the knowledge of the beginnings and the history of the development of casting – one of the oldest technical areas of human activity, which, in ancient times, played a very important role and, as far as one can remember, has been called art. The paper quotes and discusses references indicting that, in ancient times, metals and the skills connected with their treatment and casting were seen as a gift from God or gods, as well as describing the beginnings and significance of casting in old times and the development of casting manufacture technology and pointing to some of the works of the casting art masters of the ancient world.
EN
The scope of this work focuses on the aspects of quality and safety assurance of the iron cast manufacturing processes. Special attention was given to the processes of quality control and after-machining of iron casts manufactured on automatic foundry lines. Due to low level of automation and huge work intensity at this stage of the process, a model area was established which underwent reorganization in accordance with the assumptions of the World Class Manufacturing (WCM). An analysis of work intensity was carried out and the costs were divided in order to identify operations with no value added, particularly at individual manufacturing departments. Also an analysis of ergonomics at work stations was carried out to eliminate activities that are uncomfortable and dangerous to the workers' health. Several solutions were proposed in terms of rationalization of work organization at iron cast after-machining work stations. The proposed solutions were assessed with the use of multi-criteria assessment tools and then the best variant was selected based on the assumed optimization criteria. The summary of the obtained results reflects benefits from implementation of the proposed solutions.
EN
In the paper, presented is a research on effectiveness of absorbing electromagnetic waves at frequency 2.45 GHz by unhardened moulding sands prepared of three kinds of high-silica base and a selected grade of sodium silicate. 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. Values of microwave power loss in the rectangular waveguide filled with unhardened moulding sands served for determining effectiveness of microwave heating. Balance of microwave power loss is of technological and economical importance for manufacture of high-quality casting moulds and cores of various shapes and sizes. It was found that relative density influences parameters of power output and power reflected from samples of moulding sand placed in a waveguide. Absorption expressed by the parameter Pabs is not related to granularity of high-silica base: fine, medium and coarse. It was found that the semiautomatic microwave slot line supports evaluation of effectiveness of microwave absorption on the grounds of power loss measurements and enables statistic description of influence of relative density of the sandmix on penetration of electromagnetic waves in unhardened moulding sands.
EN
The aging granulate is to activate the blowing agent during the manufacturing process to granulate models can re-expand and shape the model of well-sintered granules, smooth surface and a suitable mechanical strength. The article presents the results of studies which aim was to determine the optimum time for aging pre-foamed granules for pre-selected raw materials. The testing samples were shaped in an autoclave, with constant parameters sintering time and temperature. Samples were made at 30 minute intervals. Models have been subjected to flexural strength and hardness.
20
EN
The effects of filling the core box cavity and sand compaction in processes of core production by blowing methods (blowing, shooting) depend on several main factors. The most important are: geometrical parameters of cavity and complexity of its shape, number, distribution and shape of blowing holes feeding sands as well as the venting of a technological cavity. Values of individual parameters are selected according to various criteria, but mostly they should be adjusted to properties of the applied core sand. Various methods developed by several researchers, including the authors own attempts, allow to assess core sands properties on the basis of special technological tests projecting the process into a laboratory scale. The developed criteria defining a degree or a filling ability factor provide a better possibility of assessing the core sand behaviour during flowing and core box filling, which indicate the value and structure of the obtained compacting decisive – after hardening – for strength and permeability. The mentioned above aspects are analysed – on the basis of authors’ own examinations - in the hereby paper.
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