Composite premoulded siphon blocks for blast furnace casting runners

摘要

Process for obtaining, by moulding, a blast furnace casting runner siphon block consisting of 2 composite materials of different composition, characterised in that, first of all: - a unit (1) is produced consisting of alumina-based refractory concrete of LC, ULC type containing from 65 to 95 % of Al2O3, intended to resist the physicochemical and thermal attack by the molten metal, called "insert", - the insert is then coated with a second alumina-based concrete (2) including carbon, silicon carbide and alumina, - before moulding of the insert (1) of the siphon block, a core of semicylindrical shape (6) is arranged, intended to convey the molten pig iron, - a core (4) of frustoconical shape producing a lengthwise casting runner, and a second core (5) consisting of a frustoconical shape and of a cylindrical shape facing the said semicylindrical discharge channel (6) are arranged in the upper of the siphon block before casting of the alumina-based concrete coating (2), the whole forming another casting runner which is transverse to the preceding one. IMAGE