ES358724A1 - Improved Method of Producing Copper Wire - Google Patents

Abstract

Copper rod for drawing down into wire is produced by continuously forming at least one elongated member, e.g. a single sheet 7 to be subsequently cut into a number of strips 15 by cutting rollers 14, a single strip or a plurality of separate strips, by electro-deposition on a cathode surface, e.g. formed by or carried on a rotating steel drum 3 or continuously moving belt, moving through a bath of electrolyte 2 adjacent to an anode or anodes 5 of partially refined (e.g. blister and/or scrap) copper, and continuously stripping the member from the cathode surface and passing it through the same or a different electrolyte bath adjacent to further anodes 10 of partially refined copper to build up its thickness to that required for drawing down. Preferably, the stripped member passes in a zig-zag path vertically downwards and upwards between each successive pair of a series of spaced vertical elongated anodes 10. Cutting into strips 15 may be effected as the sheet 7 passes from one part of the bath to another, or from one bath to another, or as it leaves the single or final bath. The knife edges of the cutting rollers 14 may be inclined to form strips 15 of hexagonal or near circular cross-section. At one or more intermediate stages, the member may pass out of the bath through an induction annealing chamber 12. The electrolyte may be introduced under pressure through a pipe 6 into the space 4 between the cathode surface and its associated anode (s) 5 in a direction opposite to that in which the surface is moving, e.g. drum 3 is rotated, to remove sludge. Forced circulation of electrolyte in the or each bath may also be effected. Some or all of the anodes 5, 10 may be in the form of perforated Ti containers filled with pieces of scrap copper, the containers preferably being surrounded by a porous covering of polyethylene, polypropylene or PVC. The Ti container may be annular to allow passage therethrough of a strip (Fig.4). Scrap copper may be replenished continuously during the process. The copper may be deposited on moving strips in such a way to build them up into a shape approximating to circular cross-section, by projecting the electrolyte preferentially on to selected parts of the moving strips, suitably shaping the effective surfaces of the further anodes, or by axially twisting the strips as they pass between the further anodes. Alternatively, two or more strips may be bonded together to form a rod by passing between pressure rolls or through a die.