Wyniki wyszukiwania - Biblioteka Nauki

1

Organic Moulding Sands for Production of Large-Size Castings

100%

Major-Gabryś K. , Hosadyna-Kondracka M. , Major-Gabryś K. , Hosadyna-Kondracka M.

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nr 3

2

Organic Moulding Sands for Production of Large-Size Castings

89%

Major-Gabryś K. , Hosadyna-Kondracka M.

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tom iss. 3

99--105

EN

Recently, some major changes have occurred in the structure of the European foundry industry, such as a rapid development in the production of castings from compacted graphite iron and light alloys at the expense of limiting the production of steel castings. This created a significant gap in the production of heavy steel castings (exceeding the weight of 30 Mg) for the metallurgical, cement and energy industries. The problem is proper moulding technology for such heavy castings, whose solidification and cooling time may take even several days, exposing the moulding material to a long-term thermal and mechanical load. Owing to their technological properties, sands with organic binders (synthetic resins) are the compositions used most often in industrial practice. Their main advantages include high strength, good collapsibility and knocking out properties, as well as easy mechanical reclamation. The main disadvantage of these sands is their harmful effect on the environment, manifesting itself at various stages of the casting process, especially during mould pouring. This is why new solutions are sought for sands based on organic binders to ensure their high technological properties but at the same time less harmfulness for the environment. This paper discusses the possibility of reducing the harmful effect of sands with furfuryl binders owing to the use of resins with reduced content of free furfuryl alcohol and hardeners with reduced sulphur content. The use of alkyd binder as an alternative to furfuryl binder has also been proposed and possible application of phenol-formaldehyde resins was considered.

3

The influence of the Glassex additive on technological and knock--out properties of the moulding sands with hydrated sodium silicate and new ester hardeners

89%

Major-Gabryś K. , Dobosz S. M.

Metallurgy and Foundry Engineering

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2011

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tom Vol. 37, no. 1

33-40

EN

The article takes into consideration the researches concerning inserting the Glassex additive to the moulding sands with water glass and the new ester hardeners. The investigations combine the works connected to the Glassex additive influence on the moulding sand's with water glass knock-out properties and the works connected to the elaboration of the new ester hardeners upgrading of ability to mechanical reclamation of the moulding sand with water glass.

PL

Artykuł omawia badania dotyczące wprowadzenia do mas formierskich ze szkłem wodnym dodatku Glassex oraz zastosowania nowych utwardzaczy estrowych. Przedstawione badania łączą prace autorów dotyczące określenia wpływu dodatku Glassex na wybijalność mas ze szkłem wodnym z pracami dotyczącymi wpływu nowych utwardzaczy estrowych na zdolność do regeneracji tych mas.

4

Zjawiska powierzchniowe a wybijalność mas ze szkłem wodnym

89%

Dobosz S. M. , Major-Gabryś K.

Archiwum Technologii Maszyn i Automatyzacji

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2004

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tom Vol. 24, nr 1 sp

49-56

PL

Artykuł dotyczy zagadnień wybijalności mas ze szkłem wodnym. Ta tania, ekologiczna metoda wytwarzania mas formierskich i rdzeniowych ma, niestety, poważną wadę - wybijalność mas jest staba i mała jest ich zdolność do regeneracji mechanicznej. W artykule omówiono założenia nowej, bardzo efektywnej metody poprawy wybijalności.

EN

The article focuses on the knock-out properties of moulding sands with water glass. Unfortunately, this cheap and ecological method of producing both core and moulding sands has some serious defects including poor knock-out properties and low ability to mechanical regeneration. The article describes the assumption of a new, very effective method of improving the knock-out properties.

5

Moulding sands with water glass with increased ability to reclamation

89%

Dobosz S. M. , Major-Gabryś K.

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tom Vol. 8, iss. 1 spec.

67--70

EN

The article takes into consideration the researches concerning the possibilities of increasing the abilities of reclamation of loose self-hardening moulding sands with water glass and liquid hardeners. The researches show, that the factor responsible for low efficiency of mechanical reclamation of these moulding sands is a cumulating of hydrated sodium acetate on the reclaim's surface, which is a product of reaction between water glass and commonly used in this technology - hardeners on the basis of esters of acetic acid. The presented new method is based on replacing the currently used hardener with an alternative hardener on the basis of esters of carbon acid.

6

High-temperature expansion and knock-out properties of moulding sands with water glass

89%

Major-Gabryś K. , Dobosz S. M.

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2007

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tom Vol. 7, iss. 1

127-130

EN

The article focuses on the topic of improving the knock-out properties of moulding sand with water glass and ester hardener. It is settled that the cause of worse knock-out properties of moulding sand can be brought by their thermal expansion in increased temperatures. There is a presentation of the influence of different additives, containing Al2O3, on moulding sands' expansion in increased temperatures. Within the frames of research, there was an elaboration of the influence of authors own additive- Glassex, on the expansion phenomenon of moulding sands with water glass and ester hardener. It is concluded, that the new additive stops the expansion of moulding sands and as well it improves their knock-out properties.

7

Effect of Strontium Inoculation on Hot Tearing in Aluminium Alloys

71%

Bolibruchová D. , Bruna M. , Pastirčák R. , Major-Gabryś K.

Archives of Metallurgy and Materials

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2018

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tom Vol. 63, iss. 4

1837--1842

EN

Main aim of submitted work is evaluation and experimental verification of inoculation effect on Al alloys hot-tear sensitivity. Submitted work consists of two parts. The first part introduces the reader to the hot tearing in general and provides theoretical analysis of hot tearing phenomenon. The second part describes strontium effect on hot tearing susceptibility, and gives the results on hot tearing for various aluminium alloys. During the test, the effect of alloy chemical composition on hot tearing susceptibility was also analyzed. Two different Al-based alloys were examined. Conclusions deals with effect of strontium on hot tearing susceptibility and confirms that main objective was achieved.

8

Kryteria oceny wybijalności mas ze szkłem wodnym

71%

Major-Gabryś K. , Dobosz S. M. , Zych J.

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tom R. 5, nr 17

163--168

PL

Artykuł dotyczy metod oceny wybijalności mas ze szkłem wodnym i nowym dodatkiem Glassex. Szczególny nacisk położono na nowo zaproponowaną ocenę wybijalności mas opartą o badania ultradźwiękowe. Metoda okazała się szybka, precyzyjna i bardzo przydatna.

EN

The article concerns the method of estimating the knock-out properties of moulding sands with water glass and new Glassex additive. Especially the lately proposed estimation of knock-out properties based on the ultrasound researches is taken into consideration. This method seems to be quick, precise and very useful.

9

The Tendency of Moulding Sands to Generate Core Cracks

71%

Dobosz S. M. , Grabarczyk A. , Major-Gabryś K. , Kusiński J.

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10

Modyfikacja uwodnionego krzemianu sodu jako spoiwa do sypkich mas samoutwardzalnych przy użyciu Al2O3

71%

Kaźnica N. , Grabarczyk A. , Major-Gabryś K.

Archives of Foundry Engineering

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2013

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tom Vol. 13, iss. 3 spec.

57--62

PL

Artykuł dotyczy ekologicznych mas z uwodnionym krzemianem sodu jako spoiwem. Masy zawierające uwodniony krzemian sodu wykazują niską szkodliwość dla środowiska naturalnego, jednakże charakteryzują się złą wybijalnością. W prezentowanym artykule autorzy skupili się na zbadaniu wpływu dodatków modyfikujących na bazie związków Al2O3 na właściwości technologiczne sypkich mas samoutwardzalnych z uwodnionym krzemianem sodu i ciekłymi utwardzaczami. W ramach prac określono również wpływ nowych dodatków na wybijalność badanych mas określaną w oparciu o pomiar wytrzymałości końcowej na ściskanie Rctk oraz ekspansji wysokotemperaturowej.

EN

This article is devoted to research on ecological moulding sands with hydrated sodium silicate binder. These types of moulding sands are proved to be less harmful to the environment, but unfortunately they have low knock-out properties. In the presented article authors focus their tests on the influence of new Al2O3 based additives in composition with self-hardening moulding sands with hydrated sodium silicate and liquid hardeners. Technological parameters are also measured to determine the influence of new additives on knock-out properties of tested moulding sands. The knock-out properties were estimated by measuring the retained strength Rctk and thermal expansion of examined moulding sands.

11

Autorskie badania nad doskonaleniem mas formierskich i rdzeniowych

71%

Dobosz S. M. , Jelinek P. , Major-Gabryś K.

Przegląd Odlewnictwa

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2011

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tom Vol. 61, nr 5-6

196-208

PL

rtykuł prezentuje fragmenty badań własnych autorów nad alternatywnymi rozwiązaniami mas formierskich i rdzeniowych. Celem tych badań jest wskazanie nowych kierunków w zakresie systemów wiązania mas z zastosowaniem spoiw o charakterze nieorganicznym i innych zapewniających niską szkodliwość tych mas dla środowiska. Oczywiście powinny one także spełniać wysokie wymogi technologiczne. Część z zaprezentowanych rozwiązań zostało już z powodzeniem zastosowanych w praktyce przemysłowej, inne są dopiero w fazie badań laboratoryjnych. Poszukiwanie alternatywnych rozwiązań, aktualnie bardzo szeroko rozpowszechnionych systemów z zastosowaniem żywic syntetycznych, jest koniecznością współczesnego odlewnictwa. Dotychczasowa współpraca polskich i czeskich ośrodków naukowych może te prace istotnie zintensyfikować.

EN

The paper presents fragments of authors' investigations on alternative solutions of moulding and core sands. The aim of these studies is to indicate new directions in moulding sands bonding systems with using inorganic (and others) binding materials ensuring a low environmental harmfulness. They should, of course, also meet high technological requirements. A part of the presented solutions have been already successfully applied in an industrial practice, others are at the laboratory examination stage. Searching for alternative solutions, for currently commonly applied systems with synthetic resins, is the necessity of the contemporary foundry engineering. The co-operation of the Polish and Czech research centres can significantly intensify these studies.

12

Selection of hardening technology of moulding sand with hydrated sodium silicate binder devoted to aluminum alloys ablation casting

71%

Major-Gabryś K. , Hosadyna-Kondracka M. , Grabarczyk A. , Kamińska J.

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nr 1

13

The influence of changes in active binder content on the control system of the moulding sand quality

71%

Jakubski J. , Dobosz S. M. , Major-Gabryś K.

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tom Vol. 12, iss. 4

71-74

EN

Artificial neural networks are one of the modern methods of the production optimisation. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is the assessment method of sands suitability by means of detecting correlations between their individual parameters. The presented investigations were aimed at the selection of the neural network able to predict the active bentonite content in the moulding sand on the basis of this sand properties such as: permeability, compactibility and the compressive strength. Then, the data of selected parameters of new moulding sand were set to selected artificial neural network models. This was made to test the universality of the model in relation to other moulding sands. An application of the Statistica program allowed to select automatically the type of network proper for the representation of dependencies occurring in between the proposed moulding sand parameters. The most advantageous conditions were obtained for the uni-directional multi-layer perception (MLP) network. Knowledge of the neural network sensitivity to individual moulding sand parameters, allowed to eliminate not essential ones.

14

New look at the process of reclamation of moulding sands

71%

Dobosz S. M. , Major-Gabryś K. , Hosadyna M.

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tom Vol. 12, iss. 3

19-24

EN

This paper presents a new perspective on the issue of reclamation of moulding and core sands. Taking as a premise that the reclamation process must remain on the surface of grains some not separated binding materials rests, it should be chosen the proper moulding sand's composition that will be least harmful for the reclaim quality. There are two different moulding and core sands taken into examinations. The researches prove that a small correction of their compositions (hardener type) improves the quality of the received reclaims. Carried out in this article studies have shown that such an approach to the problem of reclamation of the moulding and core sands is needed and reasonable.

15

Modyfikacja spoiw odlewniczych przy użyciu materiału biodegradowalnego

71%

Major-Gabryś K. , Grabarczyk A. , Dobosz S.

Przegląd Odlewnictwa

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2018

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tom Vol. 68, nr 3-4

80--83

PL

W artykule przedstawiono wpływ materiału biodegradowalnego – polikaprolaktonu (PCL) na wybrane właściwości mas formierskich. Do badań wytypowano szeroko stosowaną w praktyce odlewniczej masę samoutwardzalną z żywicą fenolowo-furfurylową oraz przyjazną dla środowiska masę samoutwardzalną z uwodnionym krzemianem sodu. Zadaniem nowego dodatku w przypadku masy z żywicą syntetyczną jest zmniejszenie jej szkodliwości dla otoczenia i zwiększenie elastyczności w temperaturze otoczenia. W przypadku masy z przyjaznym dla środowiska uwodnionym krzemianem sodu zadaniem nowego dodatku jest zwiększenie elastyczności badanej masy przy zachowaniu jej proekologicznego charakteru. Badania wykazały, że zastosowanie do mas formierskich 5% PCL zwiększa elastyczność w temperaturze otoczenia badanych mas zarówno ze spoiwem organicznym, jak i nieorganicznym. Wykazano również wpływ nowego dodatku na deformację mas w podwyższonej temperaturze.

EN

The article presents the influence of biodegradable material - polycaprolactone (PCL) on selected properties of molding sands. For the tests two different moulding sands were chosen. A self-hardening moulding sand with phenol-furfuryl resin and an environmentally friendly self-hardening moulding sand with hydrated sodium silicate, both of which are widely used in foundry practice. The task of the new additive for moulding mixtures with synthetic resins is to reduce its harmfulness to the environment and increase the elasticity at ambient temperature. In the case of the moulding sand with environmentally friendly hydrated sodium silicate, the task of the new additive is to increase the elasticity of the test sand while maintaining its ecological character. The research has shown that the use of 5% PCL for molding sands increases their flexibility at the ambient temperature, both with organic and inorganic binders. The influence of the new additive on the moulding sand deformation at elevated temperature was also demonstrated in the research.

16

Mechanical and Thermal Deformation of Hot-box Moulding Sands

71%

Grabarczyk A. , Major-Gabryś K. , Dobosz S. M. , Jakubski J.

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17

Modification of Foundry Binders by Biodegradable Material

71%

Grabarczyk A. , Dobosz S. M. , Major-Gabryś K.

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nr 2

18

Elasticity of Moulding Sands – a Method of Reducing Core Cracking

71%

Dobosz S. M. , Grabarczyk A. , Major-Gabryś K.

Archives of Foundry Engineering

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2017

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tom Vol. 17, iss. 1

31--36

EN

This paper focuses on mechanical properties of self hardening moulding sands with furfuryl and alkyd binders. Elasticity as a new parameter of moulding sands is investigated. With the use of presented testing equipment it is possible to determine force kinetics and deformation of moulding sand in real time. The need for this kind of study comes from the modern casting industry. New foundries can be characterized with high intensity of production which is correlated with high level of mechanization and automatization of foundry processes. The increasingly common use of manipulators in production of moulds and cores can lead to generation of new types of flaws, caused by breakage in moulds and cores which could occur during mould assembly. Hence it is required that moulds and cores have high resistance to those kinds of factors, attributing it with the phenomenon of elasticity. The article describes the theoretical basis of this property, presents methods of measuring and continues earlier research.

19

The Compositions: Biodegradable Material – Synthetic Resins as Moulding Sands Binders

71%

Grabarczyk A. , Major-Gabryś K. , Dobosz S. M.

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nr 4

20

The Influence of the Content of Furfuryl Alcohol Monomer on the Process of Moulding Sand's Thermal Destruction

71%

Dobosz S. M. , Drożyński D. , Jakubski J. , Major-Gabryś K.

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tom Vol. 59, iss. 3

1093--1096

EN

The article discusses the issue of the influence of furfuryl alcohol content in resin binders on properties of moulding sand at elevated temperature. Reducing the share of this component - due to the requirements of the European Union regarding its toxicity - may cause a decrease in temperature of moulding sands’ destruction and, consequently, the thermal deformation of moulds and the creation of many casting defects. The study examined the impact of the furfuryl alcohol content of the thermal destruction processes and on the strength of the moulding sand at an ambient temperature and the tendency to thermal deformation.

PL

W artykule omówiono zagadnienie wpływu zawartości alkoholu furfurylowego w spoiwach żywicznych na właściwości mas formierskich w podwyższonej temperaturze. Zmniejszenie udziału tego składnika – spowodowane wymaganiami Unii Europejskiej odnośnie jego toksyczności – może powodować obniżenie temperatur destrukcji masy, a w konsekwencji deformację cieplną form i powstanie wielu wad odlewniczych. W pracy przebadano wpływ zawartości alkoholu furfurylowego na procesy cieplnej destrukcji spoiwa a także na wytrzymałość masy w temperaturze otoczenia oraz skłonność do deformacji cieplnej.