A PROCESS FOR PRODUCTION OF A FERRULE OR FEEDING HEAD AND SUPPLY ELEMENT FOR CASTING MOLDS WHICH ARE EXOTHERMIC AND APPROPRIATE FOR NODULAR CASTING

摘要

A process for the production of a ferrule or feeding head and supply element for casting molds which are exothermic or insulating and appropriate for nodular casting, comprises: - inserting in the molding die an insert made up of a mixture of oxidizable metals such as aluminium oxidants such as alkaline earth metals and inorganic fluorine fluxes such as cryolite, and optionally, aluminium silicate hollow micro beads or other appropriate element for thinning or adjusting the exothermicity, the weight of the insert being 5 to 20 % of the total weight of the ferrule or feeding head and supply element, the insert acting as initiator of the exothermic reaction; and - blowing inside the die a mixture of aluminium silicate hollow micro beads, with an alumina content of 20 to 38 % weight, oxidizable metals and oxidants, together with an agglomerant, whereby the insert becomes partially embedded in the mass of the ferrule or element.