As nitrogen inflation systems begin to gain steam in the tire industry, James Hamrick hopes the market will veer toward one specific filtration method.
Mr. Hamrick, who has worked on tire programs for companies such as Western Auto Supply Co. and Pep Boys-Manny, Moe & Jack, last fall founded NitroTire. The new company sells and markets nitrogen inflation systems manufactured by On Site Gas Systems Inc., which produces nitrogen and oxygen generators.
While NitroTire markets both membrane and pressure swing adsorption (PSA) generators, Mr. Hamrick is pushing the PSA system as a better fit for the tire industry-though other companies that sell membranes beg to differ.
Nitrogen generators work essentially by filtering out other gases found in regular air to isolate nitrogen, which makes up nearly 80 percent of air.
Among the benefits, tires filled with nitrogen are believed to have a longer tread life, maintain air pressure longer and reduce rim corrosion because the larger nitrogen molecules don't migrate through the tire's walls as easily as air.
Mr. Hamrick said this spring that about 15 retailers had signed on for the systems. All but one charge for the fillups, he said-for an average of $3 per tire. The retailer not charging raised tire prices $1 instead.
A PSA system includes a carbon molecular sieve (CMS) that is essentially like a child's hollow ball with shapes cut out of the surface. The smaller oxygen, carbon monoxide and carbon dioxide molecules fit into those holes in the sieve and are held while the larger nitrogen and argon molecules are allowed to pass through into the holding tank, explained Bart Gullong, vice president for technical services for On Site Gas. Adsorption is a physical separation of materials whereas absorption represents a chemical change, he said.
Once the nitrogen and argon-which has the same inert properties as nitrogen-are removed, another valve is opened and the withheld oxygen and other molecules are released into the air. Mr. Gullong said the oxygen release will not create an explosion risk because the molecules are immediately diluted into the air.
A membrane system works essentially the same way, except that it relies on a series of hollow tubes with small holes that collect the smaller molecules while letting nitrogen and argon pass through.
Mr. Gullong said the membranes can be damaged by foreign materials, especially oil. Also, he said through regular use the membranes get ``clogged'' with the oxygen and other molecules while a PSA system releases those molecules. That clogging can reduce the efficiency and capacity of a generator, he claimed.
Though On Site Gas produces both membrane and PSA systems for various industries, Mr. Gullong believes PSA is a better fit for tire dealers. The sieves can last about 20 years opposed to a membrane's five to seven years, especially in a dirty shop environment, he said.
Also, he said PSA sieves are less expensive to replace-a factor that can become important if tire dealers are unable to charge for nitrogen inflation as more shops add it.
``If in five to seven years you have to replace that membrane system, then that's going to be pure cost because there's no income coming in,'' he said.
But Bill Phelps, commercial manager of Air Products and Chemicals Inc. in St. Louis, said membranes are, in fact, the better fit. Air Products manufactures the membranes used in Branick Industries Inc.'s nitrogen generators.
He said that oxygen is routinely released into the air from the membrane and, more important, membrane systems don't use moving parts such as a PSA's valves. He contends that a PSA carries additional costs to repair the moving parts while tire dealers could spend only $40 once or twice a year on new air filters for a membrane.
``The simpler it is, the better,'' he said of a tire dealer's needs. ``A membrane is the simplest you can have.''
Mr. Phelps said membrane systems can last about 10 years, though any intrusion of oil will kill either a PSA or a membrane. Air Products also makes membrane and PSA systems, though it has pushed membranes since it teamed up with Branick two years ago, Mr. Phelps said.
NitroTire sells six models of nitrogen generators. The starting price for a smaller machine is about $3,400, Mr. Hamrick said. Custom-built machines also are available, and NitroTire sells membrane generators as well. NitroTire's machines also include dryers that are meant to reduce vapor in the air.
But while NitroTire hopes to steer tire dealers toward PSA systems, most nitrogen generator manufacturers in general are trying to sway dealers just to the concept of nitrogen over regular air. Mr. Hamrick said many tire dealers-large and small-are paying attention to nitrogen, whether that means buying machines or by seeking information.
``The interest has really taken off,'' he told Tire Business.
He compares nitrogen inflation to early road hazard warranties, noting few dealers used to offer them-and even fewer customers asked for them. But once dealers started embracing them and educating their customers, the warranties eventually became a standard expectation in the industry. ``Today there's not hardly any tire dealer in the industry who doesn't sell road hazard warranties,'' he said.
Mr. Hamrick said another contentious question about nitrogen-whether to charge for it-remains up to the individual dealer. He recommends selling it for some extra revenue, but tire dealers know their customers' tolerances better. He suggested a range of $2 to $6 per tire.