Nitrogen tire inflation, a worthwhile alternative

Joe Benson
Nitrogen Generator National Accounts Manager
Parker Hannifin Corporation
Haverhill, Massachusetts

As fuel costs continue to escalate, fleets are under increasing pressure to maximize fuel economy and reduce tire costs. Inflating tires with nitrogen is an effective and proven way to help increase fuel efficiency, reduce tread wear, and reduce tire failure. Nitrogen inflation has been utilized in Europe, Asia, and South America for nearly a decade. Many fleets in the United States have converted to nitrogen inflation within the last two years.

The importance of maintaining proper tire inflation is well documented. Goodyear's Radial Truck Tire and Retread Service Manual states that 15% under-inflation can reduce tread mileage 8% and decrease fuel economy 2.5%. In Cummins' MPG Guide, the importance of maintaining proper tire inflation is strongly emphasized: "Every 10 psi that a tire is under-inflated reduces fuel economy by 1%." Cummins also notes that under-inflation increases tire wear rates, creates irregular tread wear and reduces casing durability.

A nitrogen generator installation at TCI, a commercial tire dealer, in Atlanta, Georgia

Tires inflated with nitrogen maintain pressure typically four times longer than compressed air. Nitrogen molecules are larger than oxygen. As a result, nitrogen molecules do not pass through (permeate) the wall of the tire nearly as quickly as nitrogen molecules. Many tire manufacturers, including Goodyear, Michelin, and Bridgestone, state in their technical bulletins that nitrogen retains pressure longer than compressed air.

Nitrogen inflation helps maximize fuel efficiency. Testing conducted by Jim Keiser of Wood County Bandag in Bowling Green, Ohio concludes, "Nitrogen will give you approximately one-tenth of a mile per gallon more than air."

In addition to maintaining pressure longer than compressed air, nitrogen inflation has numerous additional benefits. Tires inflated with nitrogen experience less inflation pressure increases in warm weather and typically run 20% cooler. This is a result of nitrogen being extremely dry and free of water vapor. Compressed air has moisture that absorbs and holds heat. When heated, water expands in volume. This creates increased tire pressure and raises the temperature inside the tire.

Fleets using nitrogen often quickly see a significant reduction in tire failure and a reduction in tread wear. Maurice Schancez of Brothers Auto Transport in Fort Lauderdale, Florida, has inflated his fleet's tires with nitrogen for three years. Maurice has experienced a significant reduction in blowouts and his tires "last 30% longer with nitrogen."

Nitrogen can be easily generated from existing shop air. Nitrogen generators typically have a fast return on investment. They are very reliable and have low maintenance requirements.

Joe Benson can be reached at (800) 343-0051 ext. 603 or jbenson@parker.com.