Inside a Power Cable Factory: How Cables Are Made

By Jianyun Cable – Professional Manufacturer of Quality Electrical Cables

Ever wondered how a simple copper rod becomes a reliable power cable capable of safely transmitting electricity for decades? This step-by-step guide takes you inside a modern power cable factory and explains the entire cable manufacturing process – from raw materials to finished product – with technical details and quality control insights.

1. Introduction: The Journey from Raw Material to Finished Cable

Power cable production is a highly controlled, multi-stage industrial process combining metallurgy, polymer extrusion, and precision engineering. Each stage is critical to ensure the cable meets international standards (IEC 60502, IEC 60228, BS 5467, etc.) for electrical performance, mechanical strength, and safety.

2. Step 1: Raw Materials – Copper & Aluminum Rods

The process begins with high-purity metal rods:

• Copper rod: ≥99.99% purity (often from brands like Aurubis or Jiangxi Copper)
• Aluminum rod: AA-8000 series for flexibility & conductivity

Rods are delivered in large coils (≈2–3 tons) and stored in controlled conditions to prevent oxidation.

3. Step 2: Wire Drawing – From Rod to Conductor

The rod is pulled through a series of progressively smaller dies to reduce its diameter and increase length.

4. Step 3: Conductor Stranding – Building Flexible Cores

Multiple individual wires are twisted together to form the conductor (Class 2 or Class 5 stranding).

5. Step 4: Insulation Extrusion – Adding the Dielectric Layer

The conductor passes through an extruder that applies the insulation layer.

6. Step 5: Semi-Conductive & Metallic Screening

For medium & high voltage cables:

• Semi-conductive conductor screen (extruded)
• Semi-conductive insulation screen (extruded)
• Metallic screen: copper tape, copper wire helix, or aluminum tape

These layers control electric stress and provide fault current path.

7. Step 6: Bedding, Armoring & Outer Sheath

Final protective layers:

• Bedding: PVC or LSOH extruded over cores
• Armoring: SWA (steel wire), AWA (aluminum wire), or tape armor
• Outer sheath: PVC, PE, or LSOH – UV & weather resistant

8. Step 7: Quality Control & Final Testing

Every cable undergoes rigorous testing:

• Conductor resistance & dimensional checks
• High-voltage withstand test (AC/DC)
• Partial discharge test (MV/HV cables)
• Insulation resistance test
• Flame retardance & smoke emission (if LSZH)
• Final visual & length measurement

9. Final Thoughts

The cable manufacturing process is a symphony of precision engineering – from melting copper rods to applying cross-linked insulation and armor. Each step is tightly controlled to produce cables that safely deliver power for decades. Understanding this process helps buyers appreciate the value of quality manufacturing and choose suppliers with strong in-house production and testing capabilities.

For premium power cables – XLPE, PVC, armored, LSZH, fire-resistant – manufactured with advanced equipment, full traceability, and rigorous quality control, contact Henan Province Jianyun Cable Co., Ltd. – your trusted partner for reliable electrical cable solutions.