How an electrical cable is made

Electrical cables are the main means of transmitting the electricity we use in our homes and especially in industry and they are familiar to most of us. However, many people wonder how electrical cable is made, what material are they made of and what is the manufacturing process?

This article is going to answer this questions and try to show, through our explanatory videos, what is the manufacturing process of electrical cables.

What is an electrical cable made of?

The technology required for an electrical cable to provide service for many years, without incident, involves complex manufacturing processes that require highly qualified personnel.

What metals are used to manufacture electrical cables?

Electrical cables are mainly made of copper. This is the best conductor of electricity, although there are also types of cables that use aluminium or other types of materials of different qualities depending on the use and type of cable in question.

How are power cables made?

By means of an illustrative video, the technician explains how an electrical cable is manufactured, from the initial drawing, through the choice of insulation, followed by the phase wiring, the auxiliary protection, the outer sheath and ending with quality control, plus other steps such as shipping and aspects of the manufacturing process that ensure it is sustainable and environmentally responsible.

How is an electrical cable manufactured?

Graphical diagram of the manufacture of an electrical Medium Voltage cable

The manufacturing process of a Medium Voltage cable is divided into seven stages: incoming feed, polymer feed, triple extrusion, thickness control, cross-linking, cooling and collection.

Input power supply

Driver input coils are supplied uninterruptedly, via an input accumulator, ensuring continuous, shutdown-free operation.

Polymer feed

The feeding of the polymers is done entirely through a clean and closed circuit (clean room), ensuring the purity of the materials from the supply packaging to the machine hopper.

Triple extrusion

Extrusion is carried out through a triple layer extrusion head, allowing perfect contact between the semiconductors, insulation and the total absence of foreign elements between them.

Thickness control

The thickness of each extruded layer is continuously monitored by an X-ray measuring head. This ensures both standardised thicknesses and perfect concentricity of the layers.


The cross-linking of the insulation and semiconductors is carried out in a nitrogen atmosphere, to eliminate the risk of water absorption, through nine independent temperature zones that allow the cross-linking progression to be perfectly adjusted to the characteristics of each material.


In this case, the final part of the catenary tube is dedicated to the controlled cooling of the cable already cross-linked. In this way, it is possible to guarantee an optimum temperature at the exit of the tube and during subsequent spooling.


The collection of the insulated cable is carried out on double winders with an automatic distributor, by means of an auxiliary pull track, which ensures perfect spooling, loop by loop and free of excessive tension.

Electrical cable manufacturing process

You can visualize the manufacturing process of a medium voltage cable in the following video.

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