DescentBB

Maybe you car afficiandos like Clutch or Tricord can verify this. A while back I heard that a company is coming out with a system to fill regular car tires with nitrogen instead of air. The claim is that regular air from a compressor is contaminated with water and oil that causes the tire to deteriorate. The problems may show up as rim leaks. Nitrogen, on the other hand, would not have these contaminates and thus a tire would last longer. Now I don't know about you but I have yet to replace a tire because the rubber has gone bad. Your thoughts?

If you have a clean and well working compressor, oil and water shouldn't be in the air to begin with.

Thats true, except how many of the gas stations have drying filters on their free air lines?

Yea, it's possible, and I suppose on some small levels it would help, but it just sounds like a way to make money. It'd be cool to know more though.

From:
http://www.dwt-gmbh.de/english/reifengas_whyn2_e.htm



Why to use nitrogen for the tire inflation

Why inert tire gas filling?

Formula 1, aviation and hazardous transport trucks use already for a long time inert fillings of tires. Most of civil drivers do not take care on their tire pressure. Because the pressure loss is reduced and the fire risk is avoided this filling of tires contributes substantially to security, comfort and economy .



What is an inert filling of tires with nitrogen?

The compressed air normally existing in the tire is replaced by an inert filling with tire gas. This gas is cleaned from particles, oil vapour and humidity. Above all especially this air is oxygen-poor, i.e. inert (= low reactive).



What causes inert filling of tires?

Inert tire gas avoids oxidation at the rim and valve seat. Also the tire rubber is protected inside against oxidation by the low oxygen share. Inflammations in the tire inside are not possible any longer, since without oxygen in air no process of combustion can take place. The loss of the molecules by the rubber wall of the tire (pressure loss by diffusion) is reduced.



What are the advantages of a more constant tire pressure ?

þ More driving safety by better handling characteristics

þ Higher durability of tire caused by optimized rolling resistance

þ More comfort by better taking up of impacts

þ Less fuel consumption caused by lower rolling resistance

Click & Clack say its not worth it:
http://www.cartalk.com/content/columns/ ... ry/02.html

Why not helium? Maybe you'd have a floating car.

[MS]Instig8 wrote:Why not helium? Maybe you'd have a floating car.

Heh, I once had that thought, too. Then someone reminded me the helium molecules are small enough to permeate the tires! (or at least the seals).

Heh - what a stupid and pointless thing to do.

Non-oxidizing - LOL. Yeah - so my Mags, which are made from Magnesium and Aluminium alloy - HEY - guess what they are coated in? Yeah, Aluminium and Magnesium oxide - which is what they're SUPPOSED to be covered in!

Non-corrosive. Yeah - so I *REALLY* need to protect my tyres from the nasty air inside. For Fock's sake - what about the nasty road on the outside! I'm pretty confident the outside of my tyres is going to be worn out a LONG time before the inside is knackered.

OK, so I've got a small leak - or need to top off my tyres - where the hell do I get a Nitrogen refill from. And even if I put .5 PSI into the tyre - of normal air - then all I've achieved is filling it with impurities...

For a MUCH better idea - why not throwh away tyres and wheels all together - and get TWEELS!

Now, That's a good idea!

indeed. refined nitrogen doesn't grow on trees (but Oxygen does haha!).

roid wrote:indeed. refined nitrogen doesn't grow on trees (but Oxygen does haha!).

You've never been around when I passed gas.

Someone should tell them something like 78% of what goes into tyres *is* Nitrogen

i have nitrogen in my tires. it was like 2 bucks per tire, or one less mcdonald's value meal. I like trying new things so i tried it. little better gas mileage, not else really though.

what I want to know is how do they completely purge the tire of air so they can get the pure nitrogen in there?

yah they did

Have you ever had to deal with a tire that wouldn't come off due to rust between the tire bead and rim Mobius?

I'm guessing... no.

Ok chipper here's the deal...

This mostly applies to Asphalt Racing.
We use Nitrogen in tires on race cars because we can't control the amount of moisture that is in copmressed air. The moisture content of a tire that was filled in an air conditioned 72f shop is going to be less then a tire filled at the race track when the temp is 90f and the hunidity is 90%.
If the moisture content in all the tires is not the same then they well grow at an uneven rate and upset the balance of the car. Nitrogen helps control this.

The only thing I could see a use for it other then racing is if you had a collector car that spent a lot of time setting in a garage.

If you got better mileage, it wasn't from the nitrogen, but the fact that your tires were finally inflated to their proper pressure.

Nitrogen expands and contracts less under different temperatures than atmospheric air, and this makes a difference if you're a NASCAR racer going 200 mph for 500 miles. If not, then there isn't any benefit for the normal driver.

Some people are not realizing that even if the inside of the tire isn't deteriorating, there is "regular" atmosphere affecting the outsides of the tire. So the argument is bunk. They are just making money off of selling you 'air.'

I go with Lobber, the only influence I see is coming from a different expansion coefficient of nitrogen when the tires warm up. On a track they can get pretty hot, not only from the road friction but especially from the brake discs in the rim well. You typically have to deflate your tires a little when everything has warmed up (after a few laps). Those laps are always taken easy for brake pad wear-in and track recon anyway.

Yes, there might be a little humidity in the air you put in your tires, but I don't see any real problem with that. Having air or moisture in your brake lines is infinitely more dangerous than inside the tire itself.

This said, I'm racing on slicks now and they don't get to be inflated at all

Tri unequal moisture in the tires is what causes them to expand at different rates when they heat up. Since nitorgen is a much stabler gas and we can buy it bottled we can control the moisture content. It just simple physics, liquids are incompressible so the tire with the most moisture will expand more. In racing we know that the tires are going to grow, the trick is to get them all to grow at the same rate.

I'm not trying to BS you, I've been doing this racing thing for a little over 27 years

I hate to break it to ya, but you will never be able to inflate a tire without moisture. All tires are lubricated on their rims with a water based compound to facilitate a proper seal against the wheel rim. Even if you inflate from the very beginning with nitrogen, you will still have some moisture in there.

perhaps so, but wouldn't you at least know exactly how much moisture would be in there?

I'd imagine the moisture from that compound wouldn't be very much compared to the latent moisture in the air, either.

The issue here seems to be getting the partial pressure of water vapor down as far as possible, so as to make the overall behavior of the tire at different temperatures more predictable. Even if you can't get all of the water (due to the seal or whatever) you can get most of it, and if you're in a context where it's really that important, it's probably worthwhile. The only question is, what contexts is it that important in?

Lothar has it exactly right. The idea is not to remove all the moisture but to control it.

Other then asphalt racing or maybe for long term storage I can see no reason to use nitrogen in a tire.

Lobber that "water based compound" is water and soap and it is not used to seal the tire to the wheel. It is so the bead will slip over the wheel lip eaiser and not damage it or the tire. "Bead Sealer" is used to seal the tire to the wheel and it is made mostly from Heptane and carbon black.
Oh yeah and while we're on the subject Rims have Spokes wheels do not. :p

Lets look at it this way. I have close to 70 thousand miles on my truck tires using plain old air from multiple sources. I'll be getting new tires this spring. In short the tread has worn out before the tire carcase has. I'm with KompresZor.