Determination of heat accumulation coefficient for oil bonded moulding sands

• Autorzy: Łągiewka M. , Konopka Z. , Zyska A. , Nadolski M.
• Języki publikacji: EN

Abstrakty

EN

The possibility of controlling the solidification and cooling time of castings creates prospects of improving their structure and by the same their properties. Thermal properties of the mould constitute therefore an important factor which is necessary to consider while seeking for the mentioned improvement. The presented work illustrates the method of determining some basic thermal coefficients of moulding material, i.e. the coefficient of temperature equalisation a₂, known also as the temperature diffusivity, and the heat accumulation coefficient b₂, which characterises the ability of moulding material to draw away the heat from a casting. The method consists in experimental determining the temperature field within the mould during the processes of pouring, solidification and cooling of the casting. The performed measurements allow for convenient and exact calculations of the sought-after coefficients. Examinations were performed for the oil bonded moulding sand of trade name OBB SAND ‘E’. The experiment showed that the obtained value of b₂ coefficient differs from the value calculated on the basis of theoretical considerations available in publications. Therefore it can be stated that theoretical calculations of the heat accumulation coefficient are thus far not sufficient and not quite reliable, so that these calculations should be verified experimentally.

Słowa kluczowe

EN

theoretical basis; casting processes; moulding material; oil binder; heat accumulation coefficient; moulding sand; temperature equalization coefficient

PL

podstawy teoretyczne; proces odlewniczy; materiał formierski; spoiwo olejowe; współczynnik akumulacji ciepła; masa odlewnicza

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2013
• Tom: Vol. 13, iss. 2
• Strony: 91--94
• Opis fizyczny: Bibliogr. 15 poz., tab., wykr.

Twórcy

autor

Łągiewka M.

• Department of Foundry, Technical University of Częstochowa, ul. Armii Krajowej 19, 42-200 Częstochowa, Polska

autor

Konopka Z.

• Department of Foundry, Technical University of Częstochowa, ul. Armii Krajowej 19, 42-200 Częstochowa, Polska

autor

Zyska A.

• Department of Foundry, Technical University of Częstochowa, ul. Armii Krajowej 19, 42-200 Częstochowa, Polska

autor

Nadolski M.

• Department of Foundry, Technical University of Częstochowa, ul. Armii Krajowej 19, 42-200 Częstochowa, Polska

Bibliografia

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