Submarine cables are a vital part of our global economy today. We rely on being able to transmit energy across the world and it’s these cables that give us the capacity to do it when it comes to ocean areas. Oil drilling is a prime example of this. In the UK, there are currently more than 180 offshore oil platforms that are reliant on a sophisticated network of subsea power and cabling. The design and manufacture of sub marine cables plays a big role in the access to energy that we have.
Why are subsea cables so essential?
They are necessary for both the transmission of large volumes of power under the water, as well as providing hydraulic, optical and electrical control to much of the equipment that is required for operations like offshore drilling. Without subsea cables we simply wouldn’t have been able to explore energy reserves in this way.
How do subsea cables work?
Most cables of this type are made up of a power conductor – this is usually copper or aluminium – and this transmits the power at a certain voltage. Outside of this core inner layer there are other layers that are necessary for insulation, protection etc.
What is the process of sub marine cable manufacturing?
The conductor is always the first part of the subsea cable to be produced during the manufacturing process. Small wires made of metal are tightly wound around a larger conductor core. When this has been done then the central section of the cable is complete. The additional layers on the outside will depend on the requirements for the cable. Insulation will be applied over the conductor, usually made of EPR (ethylene propylene rubber) or XLPE (cross-linked polyethylene). These materials are ideal for subsea cables because they are incredibly light and have positive electrical and mechanical properties. Subsea cables may also integrate other components, including fibre optic cables.
What considerations are there during sub marine cable manufacturing?
- Cables need to survive in harsh environments. That’s why strength needs to be prioritised with these cables. Manufacturing involves adding a layer of armour to the cable to help ensure it can survive its environment. This armour layer is often made of coiled, galvanised steel. Its role is to deliver tensile strength, mechanical protection and impact protection.
- Stability on the seabed is essential too. Steel armouring is often what provides this vital stability on the seabed – undersea currents can be strong and unpredictable and subsea cables must be able to stay in position.
- Moisture resistance is key. Obviously, for cables that are sitting under the sea, moisture resistance is going to be vital. This is often achieved via an outer sheath that holds all the other layers in place. This sheath is usually made from a material like polyethylene, which has ideal physical strength and moisture resistance.
Submarine cable manufacturing has a unique set of requirements and is constantly evolving to ensure more effective ways of connecting under the ocean.