PL
 |
EN
Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 7

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  piasek odlewniczy
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available remote Efficiency of additives of the polysaccharide type on physical properties of bentonite mixtures
100%
Beňo J. , Jelínek P. , Špirutová N. , Mikšovský F.
|
2011
|
tom Vol. 11, iss. 1
5-8
EN
The addition of polysaccharide additives generally aims at improving some important physical properties of bentonite mixtures, above all the stability of moulds against the water loss and prevention of surface defects of castings. Polysaccharide products of inland and foreign production were checked in mixtures of two bentonites of the Czech provenance with the same montmorillonite content. The attention was paid in particular to the abrasion resistance of mixtures during storing them under constant climatic conditions. Conclusions have shown the substantial influence of: the amount of the added additive, the kind and structural composition of the additive (pH of the water extract, electric conductance).
2
Content available remote Influence of moulding sands grain size on the effectiveness of quality control systems
100%
Jakubski J. , Dobosz S. M. , Major-Gabryś K.
|
2011
|
tom Vol. 11, iss. 2
47-50
EN
One of the modern methods of the production optimisation are artificial neural networks. Neural networks owe their popularity to the fact that they constitute convenient tools, which can be applied in an extremely broad research scope. This is caused by their ability to represent complex functions. Their non-linearity should be specially emphasised. Neural networks are gaining broader and broader application in the foundry industry, among others for controlling melting processes in cupolas and in arc furnaces, for designing castings and supply systems, for controlling moulding sand processing, for predicting properties of cast alloys or selecting parameters of pressure castings. 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 obtained by using the Statistica 9.0 program. The aim of the investigations was to select the neural network suitable for prediction the moulding sand moisture on the basis of the determined sand properties such as: permeability, compactibility, friability and compressive strength in dependence on the matrix grain size.
3
Content available remote Assessment of environmental influence of bentonite and lustrous carbon carrier - in an aspect of gases emission
84%
Bobrowski A. , Holtzer M.
|
2009
|
tom Vol. 9, iss. 1
21-24
EN
The emission results of the selected gases from a bentonite-carbon mixture and from dusts originated from dry de-dusting of the green sand processing plant (at high temperatures) are presented in the paper. In order to check and compare samples of dusts and bentonite-carbon mixtures in respect of emission of gases the Evolved Gas Analysis (EGA) was performed by means of the mass spectrometry method. This method allows to determine emission conditions of the selected chemical compounds.
4
Content available remote The cross-linking influence of electromagnetic radiation on water-soluble polyacrylan compositions with biopolymers
84%
Grabowska B.
|
2009
|
tom Vol. 9, iss. 1
41-44
EN
The results of examinations of the cross-linking influence of electromagnetic radiation - in a microwave range - on polyacrylan compositions with biopolymers, are presented in the hereby paper. The cross-linking process of the tested compositions was determined on the basis of the FT-IR spectroscopic methods. It was shown that microwave operations can lead to the formation of new cross-linked structures with strong covalent bonds. The adsorption process and formation of active centres in polymer molecules as well as in highsilica sand were found due to microwave radiations. In this process hydroxyl groups (-OH) - present in a polymer - and silane groups (Si-O-H) - present in a matrix - are mainly taking part. Spectroscopic and strength tests performed for the system: biopolymer binding agent - matrix indicate that the microwave radiation can be applied for hardening moulding sands with biopolymer binders.
5
Content available remote Applications of the systems theory to the designing of the sand preparation sub-system in foundry plants
84%
Wrona R. , Stawowy A. , Macioł A.
|
2009
|
tom Vol. 9, iss. 3
217-220
EN
This study provides the basic principles for designing the functional structure of manufacturing systems and their components. The analysis of functional values is applied to create the technological and manufacturing model underlying the design of the foundry equipment with machine units and materials handling systems. Quoted examples illustrate the approved procedure to be applied to control the sand preparation process in a foundry.
6
Content available remote Polysialates binders preparation and their influence to shear strength of foundry sand mixtures
84%
Fridrich R. , Jelinek P.
|
2008
|
tom Vol. 8, iss. 2
37-40
EN
This paper deals with polysialates water-glasses preparation. There were used various procedures with the goal to create inorganic polymer on silicon and aluminum base. The one composed of SiO2 and AlO4 tetrahedron chains. For the preparation was concentrated NaOH solution used together with metakaolinite in a way low-temperature synthesis in the presence of alkaline silicate: higher pressure and temperature (autoclave) to direct making of alkaline silicate made of sand, NaOH with metakaolinite addition and by melting fritted glass together with metakaolinite and dissolution in autoclave. The dissolving effectivity was evaluated by the concentration of aluminum in alkaline silicate and by the influence to reduce strengths after heat exposition with this inorganic binder.
7
Content available remote Gas pressure in sand mould poured with cast iron
84%
Chojecki A. , Mocek J.
|
2011
|
tom Vol. 11, iss. 1
9-14
EN
The results of measurements of gas pressure in foundry moulds made from sands bonded with bentonite, sodium silicate and furan resin were disclosed. It was found that the maximum pressure during pouring of mould with metal occurs in the case of bentonite sands, especially with the addition of coal dust. The effect of this pressure on the formation of surface defects in castings was examined.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.