The electrical wires are manufactured in several different sizes and using several conductive materials. The electrical wires are excellent conductors of heat.
An electric wire is an insulating material that is flexible and transmits electricity. The conducting material mainly used is copper. Copper is an excellent conductor of electricity. It is flexible and possesses a high-malleable property.
Electrical wires can be used in aerials, underground cables, and electrical appliances running beneath our feet in our homes and behind our walls. They carry the electricity and give us power.
There are different types of cables such as:
● HT and LT flame-retardant cables
● Flame-retardant low smoke cables
● Power and control cables
● Insulated cables
● Fire survival cables
● Solar cables
Overview of the manufacturing process of electric wires
The cable is fed into a machine that draws it out through a series of lubricated pulleys and dies stretching, lengthening, and thinning it out.
They are eventually winding it onto a giant bobbin. The cable once 10 mm in diameter is now 2 mm in diameter. The bobbin is loaded. The ends of the bobbins are cold-welded to one another, guaranteeing an uninterrupted flow once the machine starts up.
Multi-core flexible cables are twisted and sheathed with white PVC granules to obtain the final product. The white flexible cable is coiled on modern coiling machines with length measuring yards.
Each coil is packed with a suitable label and shrink wrapped with a polyethylene layer for safe and moisture-free binding. The PVC insulation is done in a double-layer process. The first layer is with Virgin PVC of Insulation and an outer layer which is very thin and commonly called skin with color PVC.
It is done to avoid the adverse effect of color pigments on the insulation resistance value of PVC as virgin PVC insulation has excellent insulation resistance.
At high speed, the stranding machines twist seven wires together, forming an electrical conductor. This is a low voltage conductor under 1000 volts the carrying you will find in cables that run electricity to your home.
Their conductors need to be insulated. So a plastic extrusion machine coats the conductor with polyethylene or PVC. The extrusion process has heated the conductor, so it has to be cooled down with water. Several conductors are mixed to form a cable. This plant performs a voltage immersing the cables in water to make sure they soak it.
They are insulated the same way as low voltage cables are insulated. The cable goes into a reel to be tested before it’s shipped out to its destination in the middle of the table surrounded by copper grounding wires and a host of other components, which is the heart of the electrical cable.
Now let us see the step-by-step process of manufacturing of electrical cable.
1. Procurement of the purest raw material
The manufacturing process starts with the procurement of the purest of raw materials from reputed suppliers. All incoming materials are subjected to a series of mechanical and electrical checks.
The plant is capable of drawing wire from 8 mm to 1.6 mm consistency and resistance tensile. The strength and size of the wire are ensured at all stages of the drawing process.
The drawn wires are then stranded to achieve Co-conductors; as per specifications, conductors are formed on sophisticated high-speed stranding machines and then compacted to ensure AC losses. To ensure optimum performance, the extensive focus is paid to the conductors, resistance, and shape.
For Insulation, the unit is equipped with a state-of-the-art CCV extrusion line. The extrusion route with filtered air inlets and a positive pressure eyes closed system ensures that the insulation process is entirely free from impurities and imperfections.
3. Twisting and laying
Insulation is followed by twisting and laying of multi-core cables.
Wires and Cables Manufacturers possess a massive drum twisting and laying up machine, which ensures that no tangential stress is applied over the Insulation; this mitigates the possibility of any shifting or migration of the insulating layers, which could otherwise result in air void formations.
This prevents any chances of failure during the entire lifetime of the cable and the manufacturer’s flexibility to provide longer cable lengths that exhibit excellent and compact designs.
4. Inner Sheathing
The later multi-core cables are provided with an inner sheathing through computerized extrusion lines using PVC compounds.
Wires and Cables Manufacturers provide extruded PVC layers over the laid-up cores to hold the twisted cores in their circular form.
5. Extrusion Process
The extrusion process also serves as an additional moisture barrier. If the outer sheath gets damaged as water cannot travel radially up to the surface of the Insulation. An armoring process follows this.
6. Armoring Process
Wires and Cables Manufacturers offer standardized armoring with aluminum or aluminum alloy wire strips for core cables and steel wires and strips for multi-core cables, a uniform and perfect mass of zinc coating on the armor, and a rust-free armor layer.
It also offers protection to the armor in case of any external damage; the cables are then provided for the PVC polymer outer sheathing through the latest sheathing machines.
7.Testing and Validation
Electric wire Manufacturers also have a modern test lab with the latest validation and testing equipment. Every cable manufactured at the plant is tested for higher conductivity, flame resistance, oxygen index, smoke density, durability, tensile properties, and thermal stability.
There are more than 30 various test parameters- physical, mechanical, electrical, thermal, chemical, and fire, that different components of cables have to pass before being certified, and that indeed puts into perspective for you.
Then the wires and cables are packed with safe moisture free and good-looking packing to delivering the material in good condition – its esteemed customers.
Thus, the manufacturing process of electrical wires and cables is complicated. If the manufacturers don’t give good quality products, the wires will not be an excellent conductor to produce electricity. So they should always take care of specific steps while making electric wires and cables.