EuroWire November 2023

Dies, Cones & Die Maintenance

Solutions for growing drawing die quantities

ceramic properties (four-point MOR bend strength, hardness, abrasion resistance and density). high-purity chemical-grade zirconia that creates a white versus yellow ceramic, and helps form a structure that has fewer microscopic defects and a finished cone with a smoother wire path for drawing. A pristine microstructure results in a cone with fewer, smaller pores or defects with a near theoretical 5.79g/cc density. When the working surface where the wire travels is polished, a cone with a low coefficient of friction is created, to ensure quality during drawing. Refractron verifies the polish or surface finish on every cone using a profilometer. Understanding that wire drawing is a complex process, and performance of cones also relies on accurate and precise dimensions, Refractron uses 100 per cent inspection of key dimensions to help The company uses the necessary reworking potential; or there may be a lack of suitably trained personnel in the drawing die workshop. To solve these problems, Eder Engineering, with more than 75 years of experience in this field, has developed two easy-to-use, complementary machines for die main- tenance, which accomplish the task with minimal trained personnel, for a die drilling range from Ø 0.05 to 9mm. The first machine is the ultrasonic USP-Twin, which is equipped with two independent workstations but requires only one operator, offering double the throughput of repaired and reusable drawing dies. The USP-Twin system is suitable for grinding and polishing the conical parts of the drawing die geometry. It has two integrated needle grinding devices, oscillating polishing tables and work cycle limits, to simplify all operations. The next step is to calibrate and polish the drawing dies – already pre-machined in the cone – in the drawing cylinder/ bearing, for which an identical throughput potential is available with the second machine, the HGM-21, so as not to cause a bottleneck in the work operation.

Depending on the quantities of wire produced and the care with which they are used, all drawing dies eventually wear out. Die specialist Eder Engineering GmbH states that the best economy and the highest performance of drawing dies, with long-lasting basic dimensions, can be achieved if they are re-polished as soon as the polish at the wire contact point in the drawing cone becomes cloudy. With this method, the drawing die can remain in use for a correspondingly long time and with the original diameter before it has to be reworked to the next larger bore area and returned to further use. The wire and cable industry, and especially the non-ferrous metal sector, increasingly uses high-performance multiple drawing machines, sometimes equipped with up to 48 lines. In each of these lines, as many as 30 drawing dies made of diamond or PCD can be in use, which sooner or later have to be professionally reworked in order to maintain the required efficiency. The growing number of drawing dies that need to be repaired presents many companies with problems: traditional maintenance machines might not offer

The USP-Twin features two independent workstations

ensure performance. The company’s quality system incorporates the laser marking of the lot number and serial number on all cones. The Refractron team has manufactured thousands of cones for drawing rod as well as intermediate and fine wire lines from a range of major manufacturers. The company also has the tools to audit and refurbish older lines that require replacement cones or upgrades from coated metal to MgPSZ. Cones up to 525mm in diameter can be manufactured. Refractron’s responsive service includes supplying quotes and order information within 24 hours. It maintains a large working inventory of standard Izory HD rings and cones at the New York factory to reduce lead times for unplanned maintenance. Refractron Technologies Corp www.refractron.com In addition to prolonging the service life of the drawing tools, the benefits of a modern die-workshop line include reduced necessary stock of die-tools; accurate and flexible refurbishment when required; increased competitiveness for just-in-time orders; full transparency over die stock and refurbishment cost; and complete in-house independence. Eder Engineering GmbH www.eder-eng.com The HGM-21 system also has two individually usable, programmable workstations and the high calibration speed required for PCD drawing dies. One operator is again sufficient, and a wide working range from Ø 0.05 to 10mm can be machined continuously. At the end of the scheduled processing time, the respective station switches off automatically, which frees personnel for other activities.

Izory HD drawing cones Refractron produces wear-resistant Izory® HD toughened zirconia cones for drawing wire at its factory in Newark, New York, USA.

Izory HD is Refractron’s proprietary magnesia partially stabilised zirconia (MgPSZ) formulation. Making its own powder (mixing, heat treating, sizing and spray drying) in its factory from high-purity chemical-grade zirconia gives the company the capability to create a formulation with optimum

Refractron Izory HD cones on a Samp DM105-80

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November 2023