Nitrogen vs Air Tyres – Advantages of Nitrogen in Tyres
By Editor News ( Mar 13, 2019 )This means that nitrogen in tyres maintains the tyre pressure for a longer period of time.
Formula One teams have annual budgets of hundreds of millions of pounds, but some of the tyre technology they use can benefit all of us. Take the example of their tires. The tyres used in Formula One are filled with 100 per cent pure nitrogen instead of normal air to boost performance and reliability. This tire technology is now available to all of us. In this article, we will see why do they do it and should we all do the same?
First, let’s talk about the basics. The air around us consists of 78% nitrogen, 21% oxygen and just 1% of all sorts of extra things like co2, argon and water vapour. When we pump our tires up with normal air we're mainly filling them with nitrogen anyway. It's the oxygen part that gets tricky. Oxygen molecules are small enough to actually pass through the tyre’s structure, one of the reasons why a tire’s pressure slowly goes down. If we measure a tyre’s pressure after using it for a certain time, we will notice that it has become under-inflated. It is clear now that the older a tire is; the lower is the quantity oxygen inside it.
As nitrogen molecules are bigger than oxygen they can't pass through the rubber structure. This means that nitrogen filled tyres maintain their pressure for a longer period of time and makes it less likely for you to end up driving around on soft tires that spoil your handling and fuel economy.
Filling tyres with nitrogen also remove another pesky element of air, water vapour. As a tire heats up under use, its pressure increases. The water content or vapour inside the tyres makes this increasingly unpredictable. As Formula One teams need to be able to predict exactly how much grip their tires have, this water vapour becomes a problem. Pure nitrogen doesn't include any water vapour so this fluctuation is removed and it becomes easy to predict a tyre’s grip.
When we fill our tyres with compressed air, there are traces of moisture and water that enters the tyre. These traces further rust, rot or corrode the tyres.
The molecular size of oxygen also plays an important role in the imbalance of the tyre pressure. The molecular size of oxygen is ¼ of the molecular size of nitrogen. Being small in size, oxygen tends to escape from the space in the rubber. Nitrogen, on the other hand, stays in the tyre, providing equal pressure to the tyre.
Since we have been using normal air to fill our tyres for more than a century, it is hard to understand the advantages of using nitrogen over air. Let’s have a look at how nitrogen is different from the air in tyres:
|Maintains tyre pressure.||Does not maintain tyre pressure.|
|Does not migrate from the tyre.||Migrates from the tyre.|
|Non-reactive in nature. Does not react with the rubber.||Reactive in nature. Oxidation rusts, rot or corrode the tyre.|
|Larger molecular size stays in the tyre.||Smaller molecular size escapes from the tyre.|
|Pure nitrogen is not mixed with any other particles and does not harm or create an imbalance in the tyre.|| |
Air has particles of water in the form of vapour or moisture. These particles cause rusting and create an imbalance in the tyre.
|Tyre life increases.||Tyre expires early.|
Another advantage of having nitrogen filled tyres is that these tyres have a longer-life than air-filled tyres. One of the reasons for the depreciation of tyres is oxidation. When a tyre is exposed to oxygen, just like any other rubber material, it hardens over time and eventually breaks down. Oxidation is a natural process, therefore, even if a tyre is not being used, it will expire eventually. Similarly, the oxygen that is inside a tyre also depreciates the tyre over time. Nitrogen filled tyres, therefore, tend to have an increased tyre life.