| 摘要 |
A device for injecting a non-oxidising gas into a furnace incorporates a graphite heating element (12) for heating a cylindrical enclosure (14) incorporating an inlet orifice (24) and an outlet orifice (26). The furnace is used for heating a lengthy object, a part of which is found in the cylindrical enclosure (14) between the inlet orifice (24) and the outlet orifice (26). The object and the furnace are displaced relative to each other according to the axial direction of the furnace. The injection device comprises two annular conduits for the passage of the non-oxidising gas, the conduits of each of the annuli being inclined at the same angle with respect to the axial direction of the furnace, and this angle being different for the annuli of the conduits, in a manner such that the non-oxidising gas is injected according to two gas curtains in the form of a cone. The gas is directed towards the summit of the cone and in the direction of withdrawal from the cylindrical enclosure (14), in a manner that prevents any air entering into the cylindrical enclosure (14) able to provoke the combustion of the graphite of the heating element. |
