12 April, 2022

How an electrical cable is made

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

In this article we are going to answer your questions and try to show you, 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, our Top Cable 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.

1. Input power supply

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

2. 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.

3. 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.

4. 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.

5. Cross-linking

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.

6. Cooling

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.

7. Collection

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 visualise the manufacturing process of a medium voltage cable in the following video.

We know that electrical wires and cables carry current from one element to another. They are the conductor through which electricity flows. These conductors are manufactured using copper and aluminum. Copper is considered a better option than aluminum because it has the quality to conduct electricity with high flexibility and very little resistance. Have you ever wondered how cables and wires are manufactured? There are several stages through which materials have to pass to produce cable and wires. All these steps are followed to determine the quality of the wire and match the industry standard.

Let’s explore the manufacturing process of cables and wires.

#1. Crushing and Grinding

The metals like Copper and Aluminum are crushed at the first step to manufacture wires. The process of crushing and grinding is done in large machines. With this process, the squandered material is removed and the metal is extracted.

#2. Drawing

Drawing wire is the next step in the manufacturing process. Material is drawn to produce different gauge wires. In this process, engineers use many days to reduce the copper size. They also use copper wire drawing lubricants for increasing the life of the day. After the successful process of wire drawing, the wire becomes thin and malleable.

#3. Heating

Heat treatment is called annealing.  In general, annealing is a procedure that allows metals to cool slowly and remove internal stresses and toughen the metal. When it comes to manufacturing wires and cables, the wires are softened by undergoing heat treatment. Tremendous pressure is applied to a metal rod to form a thinner wire. The goal of heating annealing is to avoid oxidation of the cable.

#4. Insulation

Cables contain many different wires that are wrapped together in an insulator. These cables are insulated with different synthetic materials. Insulation prevents current leakage. Some cables may require additional elements to improve protection. Engineers consider the quality of insulation materials based on capacity and heat resistance. They can use different insulation materials depending on the features of cables required.

#5. Twisting and Stranding

Please note that multiple wires often get strand to produce enhanced flexibility and electrical performance in comparison to a single wire. Manufacturers use some kinds of operators to carry out this process with efficiency.

#6. Extrusion

Basically, extrusion is a method in which materials undergo a plastic deformation process by applying a force and letting material flow through a die or orifice. In this step, engineers let the wire pass through an extruder, where the coating of plastic or other insulating material is applied.

#7. Cabling

The above steps help in preparing the basic component of the cable. Different wires are assembled and jacket together in one cable. The process is performed in a cabin station.

This is a general manufacturing process. It can be different depending on manufacturing companies and the technologies used by them. To know more about the cable manufacturing process, let’s initiate a quick talk on this number:

+91 (11) 27318598.