Authorized Dealer
WHY IS INFLATION PRESSURE MAINTENANCE SO IMPORTANT?
A properly inflated tire runs cooler and is not subject to excessive deflection that can cause micro-tearing in it’s internal structure. All tires gradually lose pressure though a complex, multi step rubber/gas solution/permeation process. Nitrogen diffuses out of the tire slower than air. Improved pressure retention saves fuel and repays the motorist for any initial nitrogen service fee. After an oil change most people notice that the vehicle rolls easier. They incorrectly attribute it to the cleaner oil when actually it is due to the soft tires being brought up to pressure.
An underinflated, hotter running tire will suffer a greatly accelerated oxidative weakening process. (ie: An added 18 degrees F about doubles the chemical degradation rate of oxidation.)
WHY IS NITROGEN BETTER FOR INFLATION MAINTENANCE
Pure nitrogen diffuses through rubber at a 30% slower rate than air; making it the choice insofar as improved pressure maintenance is concerned. Nitrogen is 50% less soluble in rubber than oxygen. Studies done by Bridgestone/Firestone in passenger tires showed that internal pressure loss rates were reduced 45% when using pure nitrogen inflation
WHY IS NITROGEN BETTER FOR TIRE DURABILITY?
Uniroyal reported in a Kyoto, Japan paper that air inflated tires failed on a test wheel at less than 250 hours while “nitrogen inflated tires did not fail at 600 hours”. A Coddington paper (Exxonmobil) also reported improved durability for nitrogen inflated tires. Karmarker/Herzlich and Karmarker in two Akron papers showed rubber elongation and rubber steel adhesion laboratory improvements. A newly developed “Stepped Angled Shearography Laser Interferometry Tire Test” at the highly regarded Akron Rubber Development Laboratory in combination with other physical tests clearly showed an advantage for the higher purity nitrogen.
PURITY, PURITY, PURITY. WHAT PURITY LEVEL IS NECESSARY IN THE TIRE?
The scientific literature says to not let the tire go below 95% nitrogen purity to get the greatest benefit. This does not exclude the common sense probability that 100% purity is better than 95%. However 100% nitrogen purity is commercially impractical and in fact cannot be scientifically established due to the natural variability from tire to tire. 98% nitrogen generator capability now state of the art and makes the required 95% nitrogen tire inflation commercially and easily attainable. Less pure nitrogen generation (more oxygen inflation contamination) must be considered marginal by not giving the tire nitrogen’s scientifically proven potential.
When a tire is seated, but completely deflated, it actually contains 14.7 psi of air’s natural 79% nitrogen/21% oxygen mixture. Engineering air gauges such as we use, don’t show this 14.7 pounds background pressure and register as zero. The chemist, when calculating the makeup of a gas must include this naturally present pressure in the gas mixture. In reality, an 80 psi tire actually has 80 psi + 14.7 psi in it. The 14.7 psi however is counteracted by the natural 14.7 psi pushing against the outside of the tire and the tire feels uninflated.
Nitrogen inflation during a tire installation requires very important controlled purging (removal of the oxygen from the atmospheric 14.7 psi of air) in the uninflated tire. Fewer purges are required to reach the +95% nitrogen purity when starting with a higher purity generator.
OTHER ADVANTAGES OF NITROGEN INFLATION
Of course moisture in the fill gas is undesirable. Tire manufacturers use very special innerliner compounds that are quite impermeable to moisture passage. Rusting of the steel belts is usually a phenomena caused by outside moisture and contaminants from cuts and unplugged punctures. Reduced moisture is an additional nitrogen inflation benefit (ie: TPMS).
Punctures and improper repairs can bring about the weakening oxidative/chemical weakening of the tire through a mechanism called Intra-Carcass Pressurization (ICP). The injury or repair (ie, external plug only or excessive buff) can allow the casing to be pressurized by inflation gas leaking past the plug or damaged inner liner. (warning: never plug repair from the outside only, a carefully applied inside patch is ALWAYS required). High purity nitrogen inflation will minimize the ICP oxidative tire weakening component.
Run flat tires can benefit from another nitrogen benefit. If a run flat is operated at zero pressure, there is the danger of overheating and an internal tire combustion. Giant earthmover and large aircraft tires are inflated with nitrogen to reduce this possibility.
THE REAL WORLD
Nitrogen tire fill gas inflation will not make a tire “bullet proof”. Failure due to bad things such as road hazard damage, improper maintenance, etc. can always happen. Proper nitrogen fill gas application will improve fuel economy and tire performance (inflation) while increasing tire reliability (reduced oxidative weakening) under certain real world abuse conditions.
Key Benefits of Proper Tire Pressure and Nitrogen:
Increased Fuel Efficiency – Correct tire pressure keeps the manufacturer's recommended “contact patch” on the road. This lessens the rolling resistance and maximizes fuel efficiency.
Longer Tire Life – When it comes in contact with other materials, oxygen causes oxidation. Oxidation can make rubber brittle and cause it to lose tensile strength. In addition, at high temperatures and pressures, oxygen reacts and damages inner tire liners and belt packages; nitrogen does not.
Increased Safety – Under-inflated tires cause 90% of blowouts. Nitrogen provides more reliable pressure for reduced blowout potential.
Improved TPMS Performance – If you have a new car, you likely are plagued by a flashing light telling you your tire pressure is low. For example, one woman's light was going off every four to five weeks. After inflating with nitrogen, her light didn't reappear for 53 weeks!
Longer Rim Life – Rim rust caused by condensation from water vapor and other gases can get caught in valves and create slow leaks in tires. Nitrogen is completely dry, so it eliminates the potential for condensation.
Who Uses Nitrogen?
NASCAR - NASCAR teams use nitrogen because it allows them to more accurately predict tire pressure fluctuation. Nitrogen fluctuates with temperature change, but it does so less than when water vapor is present. In addition, higher nitrogen levels eliminate the explosive properties of oxygen (oxygen loses its explosive properties at around 9% or less) NASCAR uses bottled nitrogen for portability. The bottles are delivered to the track by Praxair. This is the same Nitrogen cilynders that AutoGglitz uses.
Commercial Airlines – The Federal Aviation Administration (FAA) requires nitrogen in all commercial aircraft tires to eliminate the potential for water vapor (inherent in normal compressed air) from freezing at high altitudes. In addition, aircraft manufacturers such as Boeing use nitrogen membranes in their On-Board Inert Gas Generation Systems (OBIGGS) to "top" fuel tanks with nitrogen - an inert gas that does not support combustion.
U.S. Government – NASA and the U.S. military use nitrogen for many of the same reasons it used in commercial aircraft.
