To start, racing, like many performance oriented sports, is a "whole lot of monkey see, monkey do". Professional auto racing often comes down to "tenths" and the N2 in place of the "80%" stuff is very likely in the category of leaving no stone unturned. Goodyear mounts all the tires used by NASCAR and in keeping with the 'spirit' are presumed to mount all teams tires with equal precision. Personally, I can see not advantage with nitrogen over 'dry' air whether dry by refrigeration or desiccant save "convenience and cost".
I've worked "crew" for a couple racers that used nitrogen but, not for any reason aside convenience. We used the same bottles for the pneumatic tools.
I once helped restore an old aircraft and worked part time in the service station. We added air to any tire that needed it. The air was from a compressor/refrigerated dryer/filter...I never heard of any problems...course that was in the late 1950's. I can see where the portability of nitrogen in today's airports could be an advantage, though.
In vintage racing, I use compressed air as I see no advantage to spending money for something that does nothing for my lap times. My tire sponsor has the ability to use nitrogen if requested, but very few ever ask. I don't even run my air through a refrigerated dryer, just the simple double water trap on my compressor. I don't live in a humid area, though. Works for me.
Isaac, I love the Jag story...I have a friend and owner of a local cafe that just bought a new Jag last year and has succumbed to the same mentality as your marketing guy. I'll never understand and I will never be able to do more than just smile and nod my head.
You have also quantified what I have instinctively known for 60 years. Thanks.
I don't know about tires for cars and light trucks, for many years we have followed Goodyear's recommendations and guidelines for using nitrogen in large tires used in earthmoving.
I had a copy of this we used to keep as a reference for our truck shop when I worked for the dealer,
I doubt the tractor tyres got all that hot and heat plus water can attack some polymers and fibres and maybe the bonding agent between the reinforcing fibres and the rubber, however I doubt it really is an issue as for one, to degrade the fibres the water has to permeate through the rubber. Also, it does not seem to harm radiator hoses to much, but of course they will be from rubber known to be good to water at up to 250F
Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &
My first exposure to nitrogen filled tires was for loaders working in a recycling facility, the main reason there we used nitrogen inflation was for fire/explosion reduction in case of something causes a tire fire. I'm not a dirt guy, but for a short time I was one of our training instructors and I did safety related training. The Goodyear manual above was what CAT referenced for some of the training I did.
I found it interesting in the first Goodyear pub referenced that they really had no reason to recommend nitrogen inflation for over the road truck tires.
Consumer Reports wanted to find out if nitrogen is worth the price, so we purchased a Nitrogen Inflation System and checked out how well the inflation held up over a one year period. We evaluated pairs of 31 tire models of H- and V-speed rated, all-season tires used in our tread wear test from 2006. We filled one tire per model with air and the other with nitrogen. The test was quite simple: fill and set the inflation pressure at room temperature to 30 psi (pounds per square inch); set the tire outdoors for one year; and then recheck the inflation pressure at room temperature after a one year period.
The test started on September 20, 2006 and the final measurements were taken on September 20, 2007. The results show nitrogen does reduce pressure loss over time, but the reduction is only a 1.3 psi difference from air-filled tires. The average loss of air-filled tires was just 3.5 psi from the initial 30 pressure setting. Nitrogen-filled tires lost an average of 2.2 psi from the initial 30 psi setting. More important, all tires lost air pressure regardless of the inflation medium, so consumers should check their tires' air pressure routinely. No evaluation was done to assess the aging claim.
Uh? It's a great topic to discuss in a place like this. We are all interested in getting to the bottom of it, none with any fixed viewpoint, each bringing more information.
I read somewhere that the reduced oxidation you get with pure(ish) N2 is more important for off-road tyres, because they are retreaded over and over. The carcass is very expensive and has to last a long time compared with the tread.
My dad operated a lot of over- and off-road excavation equipment over the years. Inflating a tire in the field was always a pain with a gasoline-powered compressor, when everything else we had ran on diesel fuel. A nitrogen bottle was simply more convenient, took up less space (standing vertical and tied to the headache rack) than a typical compressor, and was cheap enough that we didn't even consider the cost. When the shop compressor broke down, we never replaced it, as even there it was simpler and cheaper to have another bottle or two of N2 on the rack next to the oxygen and acetylene bottles.
But he did have fun explaining all the benefits (purely made up) of nitrogen to those who would ask about it at the local cafe.
btrueblood,
I love it. Now we know that your dad was the source of all the urban legends about Nitrogen in tires. "More convenient" doesn't make nearly as good a story as "it reduces oxidation" or "it permiates slower so you have to fill tires less often", or "it improves tire wear and fuel effeciency (without an explaination of why that might be true)". Way more fun to make crap up.
We are only borrowing the nitrogen. Nearly 100% of the nitrogen in tire is returned to the atmosphere, (Except for the small amount that escapes and is lost forever. grin)
As far as field inflation, most large equipment has air brakes and the newer equipment has driers on the air brake systems. Moist iar in the brakes means frozen valves and locked brakes in cold weather.
Back in the day, we used spark plug pumps. This was an adapter that screwed into a spark plug hole and a hose ran to the tire being inflated. The adapter let some fresh air into the cylinder but I am sure that there was a lot of gasoline mixture added to the tire as well. I suspect that the addition of some gasoline and oil vapor to an old inner tube may have helped self sealing of small leaks.
I have never inflated a tire with propane, but I know some who have in an emergency.
Nitrogen?? Whatever.
Bill
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"Why not the best?"
Jimmy Carter
