TREATMENT OF LONGITUDINALLY EXTENDING MEMBERS

摘要

Metal wire 6 to be coated is passed through a tank 2 containing a volume 4 of molten zinc. The wire emerges from the bath through a refractory shroud 8 whose lower end 10 is submerged in the molten zinc. The shroud 8 has an elongate arcuate slot 18 formed therein at a level above that of the general level of the surface. In use, gas such as nitrogen is continuously bubbled into the molten zinc within the shroud 8. A gas lift pumping effect is thereby created which causes a continuous flow of molten metal over the lower edge of the slot 18. The surface of the molten zinc in the vicinity of the emerging wire is thus continuously renewed. The lift gas creates a non-oxidising atmosphere above the surface. Build up of oxide around the emerging wire is thus prevented.