Domestic water tanks are used to store water for a range of different uses including sometimes for drinking water, water to be heated, water used to flush toilets, or to store rainwater that has been harvested (collected). Leaking or escaped water can be damaging to its environment, and this is why the water tanks need to be strong and robust, protecting their contents from outside risks, damage, and leaks.
One of the best materials for making these water tanks from is a specific type of plastic known as UV polyethylene – or PE. The water tanks are usually treated so that they are not affected by ultraviolet rays (such as those from the sun), and are food-grade, meaning that they are suitable for the storage of drinking water.
Polyethylene is a polymer that is strong and durable, and resistant to UV rays when it is treated as well resistant to high impact and chemical agents – just right for the important storage of water. It is low-cost to produce and can be adapted to fit any size or shaped mould, giving you a great deal of flexibility into models, systems, shapes, and sizes of water tank. Polyethylene tanks are also lightweight and versatile for use in a number of different situations, as well as able to be made in a wide range of different colours.
How Polyethylene Water Tanks are Made
Polyethylene comes in a powder form. When it is made into a water tank, a mould is created in the shape and size of the tank that is needed. The polyethylene tank is then made using the rotation method. In this process, the polyethylene powder is added to the mould, where it is then heated to melt the powder. The mould then rotates to enable the liquid to line the inside of the mould and take on its shape.
Several layers gradually build up and this continues for between 30 minutes and 2 hours depending on the size of the tank. This is then left to cool and harden before the finished tank is taken out of the mould.
Why are Plastic Water Tanks Made from Polyethylene?
There are many reasons why water tank manufacturers choose to make their tanks out of polyethylene. At the moment, it is the material that best satisfies the needs of these tanks, in that:
- It is strong and robust and can be given ribs for extra strength if required
- It can be moulded according to the shape and size that is needed
- It is lightweight
- It is versatile
- It can be made in a wide variety of different colours
- It can protect its contents from chemicals
- It can be resistant to UV rays and damage from the sun
- It can easily be heated and melted without causing degradation of the quality of the tank
In the past, steel tanks were traditionally used to store water, but these were taken over by polyethylene tanks because they are lighter, are strong impact resistant, and also do not have the potential for issues with corrosion and rust that steel tanks have.
What is Polyethylene?
Polyethylene is a mixture of different polymers of ethylene and has the chemical formula, (C2H4)n. In the UK, polyethylene was first used during World War II, to insulate radar cables, but it is now one of the most widely used plastics in the world today.
