It’s the Water Vapor, Stupid
Remember James Carville, Bill Clinton’s legendary campaign manager who engineered an upset victory over Bush 41? He became famous for coining the phrase that effectively summed up voters’ frustration and became the campaign’s signature:
It’s the economy, stupid.
And what’s this line got to do with automobile tires? Well, of all the frustrations and problems that drivers experience using compressed air to fill tires, most can be traced to a single factor:
It’s the water vapor, stupid.
Compressed air contains moisture which, when heated, becomes water vapor. Water vapor creates all kinds of problems for the tire, the performance of the car and the overall safety of the driver. For example:
- Water vapor can cause the tire pressure to increase dramatically when driving in hot weather. This can lead to a blowout at worst or less than ideal car handling, at best.
- Water vapor can cause the tire pressure to drop significantly in cold weather, leading to underinflation which increases rolling resistance. It takes more power to set the wheels in motion which means higher fuel consumption.
- Water vapor causes corrosion of the metal components of the wheel and tire which can weaken the wheel and shorten the life of the tire.
According to this piece from Car and Driver, typical tires experience an increase in temperature by 50 degrees after half an hour of highway driving. Tire temperature increases quite dramatically when driving with improper inflation and with the presence of water vapor. If the tires get too hot, tread separation happens, and the tire will eventually come apart.
In contrast with compressed air, nitrogen is dry, so it does not carry water vapor inside the tire. Pure nitrogen also permeates the rubber more slowly than air (which consists of nitrogen, oxygen, and miscellaneous gases), which helps maintain stable inflation pressure over time. Stable inflation pressure results in better car handling, higher fuel efficiency, and longer tire life, all of which contribute to more savings.
Some car pundits recognize the tremendous benefits of inerting tires with nitrogen. But much like any innovation, widespread understanding and adoption take time. Some commentators are seemingly comfortable endorsing the status quo—that is—inflating tires with compressed air despite the known disadvantage of water vapor. Granted, for the sake of argument, that there are air compressors available which can remove moisture from air prior to inflation, however, the process is can be uneven and can produce inconsistent results, depending on ambient conditions in the shop as well as how well the compressor is maintained.
If water vapor is bad for tires, an even more worrisome condition is when so-called tire experts suffer a case of the vapors.
Think like a chemist! Fill your tires with Nitrogen
In a typical organic chemistry laboratory, many substances are highly sensitive and reactive when exposed to water or oxygen. To avoid this unintended reactions, vessels are typically enclosed nitrogen gas is used to "purge" the container of any unwanted oxygen or water vapor. This helps ensure the proper conditions to run a successful reaction.
The same strategy can be applied to automobile tires. Whether you own a car, truck, or bike, consider filing tires with nitrogen instead of traditional air to improve the longevity and integrity of tires while keeping your passengers safe on the road. While skeptics like to point out that air consists of approximately 78% nitrogen, it also contains oxygen and water vapor along with various unknown gases and impurities. Nitrogen is an inert gas and has higher purity than air, which allows automobile owners to know exactly what is in their tires.
To fill a tire with nitrogen gas, you will need an inertion chamber or a tank of nitrogen. Some systems use the permeation principle to selectively separate oxygen, water vapor, and other unknown gases from compressed air in order to isolate the nitrogen gas. A specially designed membrane composed of hollow fibers is used to remove the unwanted gases to improve the quality and purity of the nitrogen gas, which can be stored until it is needed.
It is rather straightforward to fill tires with nitrogen gas. Once you remove the valve, use the nitrogen gas tank to fill the tire with about 50-75% of nitrogen gas (about 5 lb of pressure) to ensure there's sufficient nitrogen to saturate the air space inside the tire. As the nitrogen enters the tire, it will begin to displace any air, oxygen, or water vapor that is inside. When this happens, allow the tire blow out any air, . You are effectively "purging" the tire of unwanted gases and air. Finally, continue filling the tire with nitrogen gas until it reaches the desired pressure.
Next time you need to refill your tires, think like a chemist and fill your tires with nitrogen. This will help prolong the life of your tires, keep your vehicle functioning well, and enhance the safety of you and your passengers.
References:
http://www.nitrogentiremachine.com/
How is your tire like a chocolate chip cookie?
Chocolate chip cookies are an iconic American food. They are consistently rated America’s favorite cookies, year after year. But there’s a surprising secret ingredient that keeps chocolate chip cookies fresh: nitrogen.
Chocolate chip cookies were invented in the 1930s by Ruth Wakefield, who owned a restaurant called Toll House in Whitman, Massachusetts. The recipe was an instant success, and by World War II chocolate cookies were an important addition to care packages sent to American soldiers overseas. A Nestlé ad even encouraged women to use their chocolate rations to bake cookies for “that soldier boy of yours.”
Today, Americans eat an estimated 7 billion chocolate chip cookies each year. About half of that number––3.5 billion––comes in the form of store-bought cookies. But chocolate chip cookies, full of gooey chocolate, rich butter, and tasty dough, have an enemy: mold.
Mold is a fungus that grows on food, and eating moldy food can be a serious health hazard. Sadly, the delicious ingredients in chocolate chip cookies make them a perfect breeding ground for mold. For years, cookies had a short shelf life because of mold formation.
Then came Modified Atmosphere Packaging, a technological breakthrough that nowadays helps keep all kinds of foods safe. The process removes air, including oxygen which supports mold growth, from inside packages and replaces it with gas, often nitrogen. Nitrogen is a stable, unreactive gas. Inerting chocolate chip cookie packages with nitrogen inhibits the growth of mold and the cookies stay fresh longer., and it
Nitrogen protects 3.5 billion cookies each year from mold, not to mention a host of other foods, and it can also be used to protect your tires. Oxygen is bad for tires, just like it’s bad for cookies. It contributes to oxidation which can cause the rubber to become brittle and weak, and form rust on metal wheel components. Inertion––the process of removing regular air, including water vapor, and replacing it with nitrogen––protects tires just like it protects chocolate chip cookies.
So, the next time you enjoy a delicious chocolate chip cookie, remember you can keep your tires fresh, too, with nitrogen inertion.