22/05/2025 – Niehoff technology: Flat wire drawing and annealing
Producing flat copper wire for cable shieldings
The copper shielding around the insulation layer is an important component of HV and EHV cables. It acts as a protection shield against electromagnetic radiation and is usually made of round wires. Flat wires, however, would be much more advantageous for several reasons.
Fig. 3. Drawn flat copper wire, micrograph, after the fifth shaped die (magnification = 50:1). Cross section: 7.817mm², width: 5.220mm, height: 1.624mm. © Niehoff
Fig. 1. “MSM 88 + R 503” type “RBD” line. © Niehoff
Fig. 2. Drawn flat copper wire, micrograph, after the first shaped die (magnification = 50:1). Cross section: 20.523mm², width: 5.560mm, height: 4.386mm. © Niehoff
Fig. 3. Drawn flat copper wire, micrograph, after the fifth shaped die (magnification = 50:1). Cross section: 7.817mm², width: 5.220mm, height: 1.624mm. © Niehoff
Fig. 4. Drawn flat copper wire, micrograph, after the ninth shaped die (finished die) (magnification = 50:1). Cross section: 3.192mm², width: 4.852mm, height: 0.677mm. © Niehoff