EFFECT OF TEMPERATURE ON THE VOLUME AND RATE OF GAS EMISSIONS FROM POLYSTYRENE PATTERN EVAPORATED IN THE FULL MOULD PROCESS WPLYW TEMPERATURY NA OBJETOSC I SZYBKOSC ZGAZOWYWANIA MODELU POLISTYRENOWEGO W PROCESIE PELNEJ FORMY

摘要

The technologies which use foamed expandablepolystyrene patterns (or patterns made of similar materials) arecharacterised by numerous advantages, mainly technological, butalso economic and ecological. Simple equipment reduces theenergy consumption and emission rate of impurities. Theproperly designed solid pattern eliminates parting planes andflashes on castings, reducing in this way to a considerable extentthe finishing treatment of casting done by done by handminimalising the necessary machining.The use of negative pressure in mould on pouring and coolingof castings creates favourable conditions for collecting thegaseous products of a thermal destruction of patterns. The gasescan be next neutralised or absorbed by specially chosen absorberswhich makes the process clean and friently to the environment.In this study the kinetics of the gas emission from patterns ofvarious densities, evaporated at different temperatures, has beendescribed along with its effect on the time of evaporation of these patterns.