NXF C1100/GB T2/ASTM C11000/ISO Cu-ERHC/DIM OF-Cu58/BS C101/C102 Diameter 1-200mm Length 1-12m Copper Round Bar

1. Raw Material Smelting: High-purity electrolytic copper is selected and heated to above 1100℃ in a medium-frequency induction furnace. A deoxidizer is added to remove oxygen impurities from the molten copper. After stirring and slag removal, filtration is performed to eliminate bubbles and impurities, ensuring the purity of the base material.

2. Continuous Casting: Molten copper is poured into a continuous casting machine and cooled to form a solid copper billet. The cooling rate is controlled to avoid internal cracks. After producing the rough billet, the defective ends are removed.

3. Hot Extrusion Forming: The billet is heated and held at a specific temperature before being sent to an extruder for high-pressure extrusion, forming copper rods of different diameters in a single process. This significantly increases the metal density and eliminates internal porosity.

4. Drawing and Reduction: The rough copper rod is cold-drawn through multiple drawing dies, gradually reducing the outer diameter to precisely control dimensional tolerances. Cold drawing causes work hardening; for finer specifications, an intermediate annealing process is interspersed.

5. Bright Annealing: The copper rod is sent to a nitrogen-protected annealing furnace for high-temperature recrystallization to eliminate drawing stress, restore material plasticity, prevent bending and cracking, and simultaneously isolate the surface from air to prevent oxidation and blackening.

6. Finishing and Polishing: After annealing, the bar stock is washed with alkali and rinsed with clean water to remove oil and oxide scale. Then, the outer diameter is polished using a centerless lathe and polishing machine to achieve a bright and smooth surface.

7. Cutting and End Face Treatment: The bar stock is cut to customer specifications, and both ends are milled flat to remove burrs and flash, ensuring a smooth and clean end face.

8. Inspection and Warehousing: The outer diameter, hardness, conductivity, and appearance defects are inspected. Qualified products are wrapped with protective film, sorted, packaged, labeled, and stored for shipment.