Precious metal wire drawing die
Precious metal filament. Especially for the drawing of thermocouple wires that need to work in the temperature range of 1600 ° C, it is necessary to make the bismuth polycrystalline wire drawing die and the natural diamond wire drawing die to meet the fine requirements. The original thick metal rod was drawn using a tungsten carbide wire drawing die, when the wire was pulled from inch '0.8 mm to inch 'O. At 3 mm, the polycrystalline diamond wire drawing die is used, and finally the natural diamond wire drawing die is pulled to inch '0.018 mm. The entire drawing process uses more than 60 molds. The ruthenium-platinum-plated gold used for the production of agricultural fertilizer catalyst screens is first pulled to a diameter of about φ2.2 mm by tungsten carbide, and then drawn to the final diameter by nineteen natural diamond wire drawing dies. It is 76 mm in size and then woven into mesh or sieve with aids. The jewellery industry is the largest market for gold wire, and the gold wire below φ1 mm is drawn with a natural diamond mold. Generally, 8 sets of molds are used to pull each mold at a compression ratio of 17% to o. Below 5 mm, the processing speed is 1.5 m / s. Then use 0 molds to reduce to o. 23 mm and can continue to be reduced to the minimum size used in the jewelry industry. 18 mm, after each drawing section, the gold wire should be chased to eliminate work hardening.