EoW September 2007

dies & die shops

The right PCD dies for Cu and Al rod breakdown machines

Temsa Diamond Die Division SA, Spain, specialises in the manufacture of diamond dies and tools for the cable and wire industries. manu- facturing programme covers natural diamond (ND), synthetic monocrystalline (MCD), and synthetic The company’s

cone, adapting its aperture to the particular elongation/ reduction percentages of the machines. As the rod does not always go perfectly straight into the die, a PCD blank must be used that is big enough to allow a wide open entrance angle, to prevent scratches on the rod and excessive generation of metal dust due to lack of appropriate

polycrystalline (PCD) wire drawing dies, extrusion dies and cable guides for cable coating, and special dies in PCD for pipe calibration and cable compacting. There is a common discrepancy between the actual possibilities of PCD blanks and the so called ‘maximum recommended bore size’ proposed by the PCD blank manufacturers, particularly in the design of sets of dies for the Cu and Al rod breakdown machines. calculated assuming that the dies will operate on the mid range of percentage of elongation/reduction per draft. Estimates are usually

Temsa Diamond Die Division specialises in the manufacture of diamond dies ▲

As the elongation/reduction percentages are high in the rod breakdown process, the dimensions of the PCD blanks required must be carefully considered, in order to build a suitable geometry on the die. It is advisable to perform a careful study of each dies geometry, based on the machine’s cinematic sequence, and then decide which PCD blank will suit the process. The contact point of the rod (or wires) on the reduction cone should be approximately at 50% of the cone’s length. In most cases, this involves adjusting the angle of the reduction

flow of the lubricant emulsion. Users should also beware using ‘standard’ calculations for non-standard processes, and should check with their diamond die supplier that the proposed PCD blanks are suitable for extraordinary elongation/ reduction percentages, and that a logical geometry will be built into the dies when rod breakdown machines are involved. Temsa Diamond Die Division SA – Spain Fax : +34 93 660 0473 Email : jcabrera@temsadiamond.com Website : www.temsadiamond.com

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EuroWire – September 2007