No abstract

In the conventional wire drawing process the reduction is achieved by pulling the wire through a tapered die. The minimum bore size of such a die is always smaller than the inlet wire diameter. A suitable lubricant is used to reduce the die wear and drawing load and to produce a good surface finish. Nevertheless, the problem of die wear and wire breakage during start-up is always present. In this paper a new technique of wire drawing is being reported which eliminates the problem of wear and breakage during start-up and also the need to have the diameter of the leading end of the wire reduced for easy insertion through the die. The reduction of the wire diameter is affected by means of the hydrodynamic action of a polymer melt lubricant in conjunction with a long tapering tube, the diameter of the tube being greater than the nominal wire diameter. Reductions in area of up to 21 per cent can be obtained in one single pass using this dieless reduction unit.