I have not given this nitrogen thing much thought. I guess I will have to read up on this at work. I will say this, something no one has mentioned. 1 breath of 100% nitrogen and you are down and out. More then 1 and you are dead. My plant uses it when they want to clear a line or vessel of combustible gases because if there is a spark, it won't light off in the presence of 100% nitrogen. There has been many lives lost do to nitrogen intake. The one that gets most people is seeing a guy go down in a vessel and they think they can get in, save the guy and get out only to go down themselves. This is DEATH waiting to happen. I don't even know where one would go to fill their tires with nitrogen! If you are going to use it, just make sure you are in a well ventilated area and DO NOT BREATH IT IN.

 

Why the stability reason used by race teams?

Right, classified no differently then CO2 or Helium correct? Our atmosphere is 78% nitrogen. Yet when vented into the atmosphere it's totally dissipates to harmless levels.

Unless you're sucking on the tank (bursting your lungs) or in a very confined, oxygen tight space, it's harmless.

What vessel are you talking about?? You're thinking of methane?

 

Maybe it has something to do with inherently low moisture content in commercially supplied nitrogen.

Other cited advantages for race teams have more to do with fire resistance (pure nitrogen, versus air, will not support combustion).

 

Nitrogen is less susceptible to temperature change than straight atmosphere. However, the temp changes our bikes are subjected to are too narrow for nitrogen to have any real effect. We use nitrogen in commercial aircraft tires because of the changes they encounter. Say you get on a plane in Phoenix, it's 100 degrees. The plane climbs to 38,000 feet where ambient temp is about -50 F. That's a 150 degree difference. It flies for a couple of hours, and gets what we call "cold soaked", then lands in Chicago, where it's 85 F, a 135 degree difference. The pressure is pretty much unchanged. The most a tire, non-flying, on a given day is subjected to is what, 30, maybe 40 degree change. Check your pressure with any regularity and don't waste money on nitrogen. If your worried about moisture content and rusting rim, you ought to have a filter and drier inline on your compressor anyway. Not to mention draining the tank for moisture too. Don't over think things.

 

I'm in HVAC also..... A vessel is a vessel. If it is sealed it will still increase/decrease pressures if heat is applied to it. Doesn't matter if it's filled with nitro or compressed air. If you're testing for leaks in the morning and let it sit with the nitrogen in it as soon as the sun hits it, the pressures increase. Will it increase alot? No, but it still does, even with nitro. Just like in tires, the pressure will still increase. Granted you're not pumping it up to 300+psi, but it's still a closed vessel and the same laws apply.
Personally, I think it's the placebo effect. A sealed tire is a sealed tire. Air just doesn't disappear. If you lose pressure, you have a leak whether it be at the valve core, rim itself, hole in tire, or it wasn't sealed properly.

 

Because tires filled with nitrogen stay closer to there static pressure as the tires change temperature. Tire pressure raises and lowers considerably as the tire temperature goes up and down. A tire at 70 degrees may be at 32 lbs of pressure, then when the same racing tire hits 140 degrees, the pressure may raise a pound, and then another pound or two at 220 degrees. On a street car, no one cares about slight pressure changes. On race cars, a pound or two difference in tire pressure is drastic. As I understand it, nitrogen expands and contracts less, so the tire pressure remains more stable as the tires heat up. Street cars.....who cares, right. But on race cars, well races are won and lost over far less significant things than fluctuating tire pressures.

 

****ing hilarious. 3 pages on this? You don't have to delve into the CRC handbook and crunch some numbers to know it wouldn't make a noticeable difference. Cash down a hole.

 

Nitrogen defies normal gas thermal expansion laws? I find that hard to believe, but will await your evidence.

Here's an article on nitrogen for inflating tires, from people who might be in a good position to know:

http://www.tirerack.com/tires/tirete...jsp?techid=191

 

I know but thank you. I was questioning the other guy.

Per same article, this is what we were getting at,

"•Nitrogen assures more consistent pressure increases due to increases in operating temperatures in a racing environment because of the absence of moisture. This is especially good for participants in track days, high-performance drivers education schools and road racing."

 

Fun thread. Years ago, I had a B-1 bomber landing gear engineer tell me nitrogen servicing was all about eliminating moisture. We used to argue about this in the B-52 world years ago. We also had problems with liquid nitrogen carts when it was wicked cold in northern Maine. Never did figure that one out. Boss wanted nitrogen in everything. We were to be purging everything and reservicing with nitrogen. When asked for updates, I would tell him we were about 80% there. Took him months to figure that one out. That was a good link too.