An annealing process:
Annealing is generally electrical contact, electrode annealed round (touch wheel) will even import the high-current copper wires, copper wire to achieve the preheating and heating. Preheating is copper wire heated to high temperature oxidation will not, generally 250 degrees; heating is heated to annealing temperature copper wire, usually 500 to 550 degrees, so that recrystallization heating section with steam protection against copper oxidation, then after water cooling, the complete annealing (softening) process.
Second, the technical requirements:
1, annealing speed and voltage and pull-up speed should be kept synchronized.
2, annealing and annealing current is proportional to the square of diameter, wire size should be set according to current annealing. Soft annealed copper wire to ensure performance meets GB3953 requirements or desired performance.
3, up tension line storage device by adjusting the pressure of the cylinder.
4, copper wire of diameter deviation should be consistent with the provisions of GB3953.
Third, the narrow diameter of the reasons:
copper produced in the process of drawing hardening, annealing soften, reduce the tensile strength of copper wire, plastic and elongation increase. In the closing line tension under the effect of narrowing the diameter is inevitable. However, should control the diameter of narrow scope, generally not more than 0.02mm (determined according to the size of diameter). If the take-up tension decreases, annealed copper wire between the wheel will shake, poor contact, the phenomenon of emergence points spark, is easy to break and accelerate the annealing wheel damage. Therefore, the choice should be based on the size of diameter up tension.
Four measures:
will reduce the amount of wire, to the aperture on the sizing die.