Nitrogen Filled Tires
Rudy Hiebert
& cons but haven't seen what it costs? It might even be good for the
common tires in trucks and family cars.
fweddybear
>& cons but haven't seen what it costs? It might even be good for the
>common tires in trucks and family cars.
I'd be interested in hearing too... I am having the tires on my vehicle
replaced somewhere around the end of october and the tire place told me they
use nitrogen instead of oxygen. He said the molecules are larger than
oxygen and there is less likely to be a leak. That was the first time I
heard about that and honestly wasn't sure if he was bullshiting me or not.
Fwed
Bruce Chang
"fweddybear" <fwedd...@cox.net> wrote in message
news:p0rZc.231325$Oi.44745@fed1read04...
of 8. With just that information, it would appear that oxygen molecules
would be bigger than nitrogen molecules. No one fills tires with pure
oxygen and the air we breathe is already mostly nitrogen anyhow.
Rex B
First off, remember that common air is 70% or so nitrogen. Another 20% (down 10%
from 1900) is oxygen.
Oxygen carries moisture - water molecules - which expands when hot.
Nitrogren does not absorb water and does not expand as much when hot.
Nitrogen also permeates the rubber a little more slowly.
So the benefit is slightler slower leakdown and more stable pressure
differential between cold and hot tires.
Another slight benefit is rubber degradation over long-term (years) storage.
for a street vehicle the advantage is almost negligible. I certainly wouldn't
pay extra for it unless I was super-anal about my vehicle.
For a racing vehicle the benefits are very clear, as tire pressure and
temperature are critical. Still only the most serious racers go to the trouble
(I don't).
Texas Parts Guy
el Diablo
"Bruce Chang" <bec...@swspambegonebell.net> wrote in message
news:6wrZc.15849$ql2....@newssvr22.news.prodigy.com...
Although you are mostly correct. The reason that pure nitrogen is an
advantage over oxygen which is about 85% nitrogen is that pure nitrogen
won't expand and contract like oxygen does with temperature changes. Your
tires heat as you drive and the oxygen expands. That's why tires presser
reads higher after you drive them.
With pure nitrogen the pressure remains almost unchanged. That's the true
benefit, less tire wear and safety.
Brian
Ignasi Palou-Rivera
What a load of nonsense. Nitrogen and oxygen are both diatomic gases
and as such their physical properties are very similar. Nitrogen is an
inert gas, and oxygen is much more reactive. Ther main advantage of
pure nitrogen for tires is the guarantee that it's dry, that is there
is no water vapor (steam) present on it. Steam *is* compressible
(actually what it does is condense into liquid water with pressure
having the effect of the overall gas mixture compressing.) I'm sure
that if you used equally dry atmospheric air (or oxygen) the
difference would be totally irrelevant.
--
Ignasi.
(using SPAM trap e-mail address)
Threeducks
You obviously slept through high school chemistry. It doesn't matter
what the gas is, if you raise the temperature, the pressure will also
increase. Remember, PV=nRT?
Nate Nagel
What the hell? who would ever put OXYGEN in their tires? sounds like a
disaster waiting to happen. Think about it... to burn something, you
need fuel and an oxidizer. A classic example of an oxidizer is... wait
for it... OXYGEN! yeah, let's fill a container made of fucking
HYDROCARBONS for fuck's sake with the best oxidizer known to man.
The correct explanation would be, tires are normally filled with regular
ol' atmospheric air, but are more stable pressure-wise when filled with
pure nitrogen. Now air is mostly N2 anyway, but the thing is, if you
use pure N2, there's no water vapor in it anywhere, so you don't have to
deal with the water vapor changing state. However, you still have an
increase in pressure with increased temperature, remember, PV=nRT, it's
just not as dramatic an increase as you get with really humid air. The
same effect could be achieved by using air that's been dried somehow,
but N2 is cheap enough in bulk quantities that it doesn't matter that much.
BTW size of molecules has absolutely jack to do with why use nitrogen,
as air is mostly N2 anyway, and as another poster pointed out, N2 and O2
(the other major component of air) are fairly comparable in size.
nate
--
replace "fly" with "com" to reply.
http://home.comcast.net/~njnagel
el Diablo
"Ignasi Palou-Rivera" <ipalou...@yahoo.com> wrote in message
news:uisax4...@yahoo.com...
Exactly my point, oxygen due to it's make up will expand and contract more
than nitrogen. The reason you don't get dry air is because of the
temperature changes.
Brian
el Diablo
"Rex B" <rex@@txol.net> wrote in message
news:41364be4....@news.txol.net...
The fact that there is a benefit is as you say negligible, and I agree. It's
like using synthetic oil over high grade mineral oil. It's better but only
slightly.
Brian
el Diablo
"Nate Nagel" <njn...@flycast.net> wrote in message
news:HsydncarlK9...@comcast.com...
I don't think anyone here is talking about pure oxygen.
Brian
el Diablo
"Threeducks" <three...@comcast.net> wrote in message
news:WoidnYg03qv...@comcast.com...
Now I wasn't sleeping in High School or Collage. Different gases expand at
different rates.
Brian
RWatson767
>Nitrogen Filled Tires
He said the molecules are larger than
oxygen and there is less likely to be a leak.
Like from a zillion to a few zillion to an inch or more.
Bob AZ
fweddybear
>>Nitrogen Filled Tires
I said that only because thats what the guy behind the counter selling
the tires told me. After all, when you go anywhere to purchase products for
your use, the salesperson you speak with should know their product and be
informative about it.....he is the one you go to for advise. I also stated
that I wasn't sure if he was bullshitting me or not, so there was no way I
could tell if what he was saying was true. Thus my opening line of how I
would be interested to know as well.....since that was the first time I ever
heard of such a thing.
Apparently, the difference is negligable (sp) from all the posts, so it
was an interesting topic to learn about....... even though I was not the
original poster on this subject.... lol
Fwed
Boris Mohar
>Now I wasn't sleeping in High School or Collage. Different gases expand at
>different rates.
>
>Brian
>
That is because you didn't go to either.
pV=nRT
where p is the pressure and V is the volume
and n is the number of moles, R=0.0821 L atm mol-1 K-1
(that is, R is the gas constant), and T is the temperature.
Do the numbers.
--
Boris
RV
>
>Although you are mostly correct. The reason that pure nitrogen is an
>advantage over oxygen which is about 85% nitrogen is that pure nitrogen
>won't expand and contract like oxygen does with temperature changes. Your
>tires heat as you drive and the oxygen expands. That's why tires presser
>reads higher after you drive them.
>With pure nitrogen the pressure remains almost unchanged. That's the true
>benefit, less tire wear and safety.
>
>Brian
>
I dont know about nitorgen but the theory about changing tyre pressure
doesnt sound right.
In my years of road racing superbikes air pressure increases with heat
was an advantage not a disadvantage.
Optimal pressure is set to keep the tyre from overheating at the
hottest condition but hot enough to have optimal traction.
Before the tyre fully warms up it is favourable to have a few less
pounds in it, that itself generates heat faster in the tyre and brings
it up to temp faster than if the air was the same from cold tyres up
to hot tyres.
A fixed air pressure throughout would result in full pressure cool
tyres and pretty hairy first lap of the race.
Nate Nagel
Then what, exactly did you mean by "oxygen?"
Nate Nagel
I'll help. Assuming no leaks, n is constant, and V is close enough to
constant to be considered such for the purposes of a back of the
envelope calculation.
wait for the light bulb...
Ray
You use nitrogen in race tires because it's inert. Tires filled with
pure oxygen would be a very_bad_thing.
Race tires use "clean" Nitrogen gas - no water. Ever drained your air
compressor? Water. From the moisture in the air. In NASCAR/F1 where
you measure your pressure to the .5 pound the air needs to be the same
for each tire - that's why they use nitrogen. Water throws a wrench
into the consistency side of it.
For anything else it's a waste of money. Heck, when was the last time
you checked your tire pressure? Unless it was today... you're not anal
enough for nitrogen.
Ray
clifto
> el Diablo wrote:
>> I don't think anyone here is talking about pure oxygen.
>
Why, oxygen, of course. You know, it's a mixture of pork fat, mahogany
wood stain, cream cheese and sarsaparilla.
No, wait, he meant Oprah's new cable network.
Or maybe it was the 12-ounce size of Oxy-Clean.
--
"The Democrats are all over this. Democratic strategists feel John Kerry's
war record means he can beat Bush. They say when it comes down to it, voters
will always vote for a war hero over someone who tried to get out of the war.
I'll be sure to mention that to Bob Dole when I see him." -- Jay Leno
Nate Nagel
> Nate Nagel wrote:
>
>>el Diablo wrote:
>>
>>>I don't think anyone here is talking about pure oxygen.
>>
>>Then what, exactly did you mean by "oxygen?"
>
>
> Why, oxygen, of course. You know, it's a mixture of pork fat, mahogany
> wood stain, cream cheese and sarsaparilla.
>
> No, wait, he meant Oprah's new cable network.
>
> Or maybe it was the 12-ounce size of Oxy-Clean.
>
Maybe I'm the only one who finds this amusing, but wouldn't it be a cool
(in a "damn, that blowed up real good" sort of way) trick to play on
someone (who you really, really, really hate of course) to actually fill
their tires from an oxygen tank... especially if they have magnesium
wheels...
I wonder if you'd have to get an actual flat to achieve combustion or if
at some point it would light off by itself...
Garth Vader
"Bruce Chang" <bec...@swspambegonebell.net> wrote in message
news:6wrZc.15849$ql2....@newssvr22.news.prodigy.com...
>
Actually, I've been filling my tires with HYDROGEN for years. As it's
lighter than air, I actually improve my mileage as a direct result of the
'lift' that I get from the hydrogen! Oh, the humanity!
C. E. White
"Air" is already 80% Nitrogen. So even if the O2 Molecules
leak out at a faster rate, refilling youir tires on a
regular basis will eventually result in your tires mostly
being filled with N2.
An N2 molecule is only about 7% larger than an O2 molecule,
so I doubt this explanation makes much sense. Racers use N2
becasue the pressure change as the tire heats up is more
predictible than with air which included a significant and
highly variable amount of water vapor which greatly affects
the pressure vs temperature curve - at least for racers who
worry about 0.5 lb of air pressure. For you and me, the
difference is trival.
Ed
C. E. White
Bruce Chang wrote:
> uh.. Nitrogen has an atomic number of 7 while Oxygen has an atomic number
> of 8. With just that information, it would appear that oxygen molecules
> would be bigger than nitrogen molecules. No one fills tires with pure
> oxygen and the air we breathe is already mostly nitrogen anyhow.
Actually the atomic radius of Nitrogen is larger than the
atomic radius of Oxygen. Don't know why - I guess a physics
major can explain the difference.
O2 is highly reactive. N2 is not reactive at all, so that
might be one reason for using N2 instead of pure O2.
However, the case for using N2 instead of air, which is 80%
N2 is probabkly shaky for normal drivers (i.e., not racers).
Ed
C. E. White
el Diablo wrote:
> Although you are mostly correct. The reason that pure nitrogen is an
> advantage over oxygen which is about 85% nitrogen is that pure nitrogen
> won't expand and contract like oxygen does with temperature changes. Your
> tires heat as you drive and the oxygen expands. That's why tires presser
> reads higher after you drive them.
> With pure nitrogen the pressure remains almost unchanged. That's the true
> benefit, less tire wear and safety.
Wrong. Both O2 and N2 change pressure with changes in
temeprature. In fact the difference between O2 and N2 is
trival in this respect. Air is more of a problem becasue it
contains water vapor. This has a larger effect on the
temperature pressure curve. Racers are looking for a
predictable pressure temperature curve. Air with its varying
constituent of water vapor is not as predictible as pure N@.
Pure O2 is very reactive and is not safe for filling tires.
Ed
C. E. White
el Diablo wrote:
> Exactly my point, oxygen due to it's make up will expand and contract more
> than nitrogen. The reason you don't get dry air is because of the
> temperature changes.
Oxygen is oxygen! It's makeup is oxygen atoms. Don't confuse
"Air" with oxygen. Air is somwherre close to 79% N2, 20% o2,
and 1% other stuff (CO2, H2O, etc, etc,etc).
Ed
C. E. White
Threeducks wrote:
> You obviously slept through high school chemistry. It doesn't matter
> what the gas is, if you raise the temperature, the pressure will also
> increase. Remember, PV=nRT?
You are over simplifying. PV=nRT is the IDEAL gas law. N2 at
normal (i.e., human survivable) temperatures is not too far
from an ideal gas. Air, with a significant load of water
vapor, deviates quite a bit from an idel gas - mostly
becasue of the water vapor. When you start working with
gases near the temperature/pressure that they can condense,
the ideal gas law goes out the window and you need to use
pressure / temperature tables. Since water vapor can easily
condense under normal conditions, it is not an ideal gas.
The presence of water vapor make the pressure rise with
increase temperature less predctible, which is why racer
prefer pure N2.
Ed
C. E. White
el Diablo wrote:
> > You obviously slept through high school chemistry. It doesn't matter
> > what the gas is, if you raise the temperature, the pressure will also
> > increase. Remember, PV=nRT?
>
> Now I wasn't sleeping in High School or Collage. Different gases expand at
> different rates.
I suggest you review your chemistry book. For gases like N2
and O2 at atmospheric temperatures and pressures, the
difference is trival. It is not trivial for water vapor
(H2O).
Ed
Brian
tires several times after seating the bead, so that the air that's in the
tire is diluted with nitrogen to a sufficient extent that the benefit of dry
nitrogent is applicable. Race tires often run at 15 - 18 psi so with only
one atmosphere of pressure differential, I would expect that just a simple
fill of nitrogen would result in a 50% mix or thereabouts.
I just set my pressures hot after the first session, measure them after they
cool off so I know what the cold pressure is compared to where I want them
hot, and pretty much ignore them after that.
Brian
"fweddybear" <fwedd...@cox.net> wrote in message
news:sGtZc.231579$Oi.215839@fed1read04...
Threeducks
gases well above their critical temperature and at low pressure (32 psi
is low pressure), they will behave as an ideal gas. The critical
temperature of N2 is somewhere around -149 C, O2 is -118 C, so any
temperature one is going to see in the tire is definitely in the ideal
gas region. PV = nRT, raise T, P has to go up.
C. E. White
Brian wrote:
>
> One thing no one has mentioned is that racers that use nitrogen purge the
> tires several times after seating the bead, so that the air that's in the
> tire is diluted with nitrogen to a sufficient extent that the benefit of dry
> nitrogent is applicable. Race tires often run at 15 - 18 psi so with only
> one atmosphere of pressure differential, I would expect that just a simple
> fill of nitrogen would result in a 50% mix or thereabouts.
If you start out with "air" your tires already have about
80% nitrogen.
Ed
Threeducks
>
> Threeducks wrote:
>
>
>>You obviously slept through high school chemistry. It doesn't matter
>>what the gas is, if you raise the temperature, the pressure will also
>>increase. Remember, PV=nRT?
>
>
> You are over simplifying. PV=nRT is the IDEAL gas law. N2 at
> normal (i.e., human survivable) temperatures is not too far
> from an ideal gas.
You can't get any closer to an ideal gas than N2 and O2 at these conditions.
> Air, with a significant load of water
> vapor, deviates quite a bit from an idel gas - mostly
> becasue of the water vapor.
We weren't talking about air with water in it. It was air vs. N2. I
can easily get dry air to put in my tires.
> When you start working with
> gases near the temperature/pressure that they can condense,
> the ideal gas law goes out the window and you need to use
> pressure / temperature tables.
Or an equation of state. But you would only need to use it for the H2O
component because N2 and O2 will be ideal gases at these conditions.
Don't believe me? Do the calcalculation with and EOS like Peng-Robinson
and compare to the ideal gas law.
> Since water vapor can easily
> condense under normal conditions, it is not an ideal gas.
Nobody said it was. What fraction of the gas in the tire is water
vapor? If you do the calculation, you'll find out it's very small
compared to the amount of N2 and O2 in the tire.
> The presence of water vapor make the pressure rise with
> increase temperature less predctible, which is why racer
> prefer pure N2.
I'd buy that, but that isn't what the previous poster was talking about.
Of course, if one knew what the humidity level of the air that they
put in the tires was, it would be entirely predictable what the pressure
rise with temperature would be. Or if one used dry air, they could do
all their predictions with the ideal gas law.
Alex Rodriguez
rudyxh...@yahoo.com says...
>
>
>Has anyone used nitrogen in non-low profile tires? I checked the pro's
>& cons but haven't seen what it costs? It might even be good for the
>common tires in trucks and family cars.
What benefits are you supposed to get using nitrogen?
--------------
Alex
Alex Rodriguez
>
>
>>Has anyone used nitrogen in non-low profile tires? I checked the pro's
>>& cons but haven't seen what it costs? It might even be good for the
>>common tires in trucks and family cars.
>
>replaced somewhere around the end of october and the tire place told me they
>use nitrogen instead of oxygen. He said the molecules are larger than
>oxygen and there is less likely to be a leak. That was the first time I
>heard about that and honestly wasn't sure if he was bullshiting me or not.
Oxygen? I'd like to know which tire place is using oxygen to fill tires?
I think they are serving up a bunch of BS. I'm sure they are just pumping
regular air out of the atmospere, which means oxygen and nitrogen, along with
some other good stuff.
------------
Alex
Alex Rodriguez
>I don't think anyone here is talking about pure oxygen.
Does that mean they are also not talking about pure nitrogen? In which
case I want to know what they are talking about?
---------------
Alex
ray
>> The presence of water vapor make the pressure rise with
>> increase temperature less predctible, which is why racer
>> prefer pure N2.
>
>
> I'd buy that, but that isn't what the previous poster was talking about.
> Of course, if one knew what the humidity level of the air that they put
> in the tires was, it would be entirely predictable what the pressure
> rise with temperature would be. Or if one used dry air, they could do
> all their predictions with the ideal gas law.
But when you're measuring lap times to the nearest .001 second and tire
pressures to the nearest .25 pound and you have a tire budget of "lots"
you worry about using the exact same air in each tire for the whole
season. (regular air, even dry air just isn't close enough.)
Regular people just use regular air. If you're not in F1 or NASCAR you
probably can use regular air in your tires too...
Jeff Deeney
"Alex Rodriguez" <ad...@columbia.edu> wrote in message
news:ch7j9c$454$7...@newsmaster.cc.columbia.edu...
First of all, air is 70% nitrogen.
Pure nitrogen will be dry. Whether this is of benefit is questionable.
Pure nitrogen will also expand less with changes in temperature. A
non-issue for most of us.
I only use pure nitrogen when recharging gas shocks.
-Jeff Deeney-
y_p_w
> "Threeducks" <three...@comcast.net> wrote in message
> news:WoidnYg03qv...@comcast.com...
> > el Diablo wrote:
> > > "Bruce Chang" <bec...@swspambegonebell.net> wrote in message
> > > news:6wrZc.15849$ql2....@newssvr22.news.prodigy.com...
> > >
> > >>"fweddybear" <fwedd...@cox.net> wrote in message
> > >>news:p0rZc.231325$Oi.44745@fed1read04...
> > >>
> > >>>>& cons but haven't seen what it costs? It might even be good for the
> > >>>>common tires in trucks and family cars.
> > >>>
> > >>> I'd be interested in hearing too... I am having the tires on my
> > >>
> > >>vehicle
> > >>
> > >>>replaced somewhere around the end of october and the tire place told me
> > >>
> > >>they
> > >>
> > >>>use nitrogen instead of oxygen. He said the molecules are larger than
> > >>>oxygen and there is less likely to be a leak. That was the first time
> I
> > >>>heard about that and honestly wasn't sure if he was bullshiting me or
> > >
> > > not.
> > >
> > >>>
> > >>>
> > >>
> > >>uh.. Nitrogen has an atomic number of 7 while Oxygen has an atomic
> number
> > >>of 8. With just that information, it would appear that oxygen molecules
> > >>would be bigger than nitrogen molecules. No one fills tires with pure
> > >>oxygen and the air we breathe is already mostly nitrogen anyhow.
> > >>
> > >>
> > >>
> > >
> > >
> > > Although you are mostly correct. The reason that pure nitrogen is an
> > > advantage over oxygen which is about 85% nitrogen is that pure nitrogen
> > > won't expand and contract like oxygen does with temperature changes.
> Your
> > > tires heat as you drive and the oxygen expands. That's why tires presser
> > > reads higher after you drive them.
> > > With pure nitrogen the pressure remains almost unchanged. That's the
> true
> > > benefit, less tire wear and safety.
> >
> > what the gas is, if you raise the temperature, the pressure will also
> > increase. Remember, PV=nRT?
>
> different rates.
And for all practical purposes, the difference in expansion rates is
neglibible.
y_p_w
> and as such their physical properties are very similar. Nitrogen is an
> inert gas, and oxygen is much more reactive. Ther main advantage of
> pure nitrogen for tires is the guarantee that it's dry, that is there
> is no water vapor (steam) present on it. Steam *is* compressible
> (actually what it does is condense into liquid water with pressure
> having the effect of the overall gas mixture compressing.) I'm sure
> that if you used equally dry atmospheric air (or oxygen) the
> difference would be totally irrelevant.
Nitrogen isn't inert, although it's a lot less reactive than oxygen.
If nitrogen were inert, we wouldn't have to worry about such things
as NO2 emissions, and we wouldn't have people using NOS kits for
drag racing.
Helium is inert. I've heard of bicycle tires being pumped up
with helium to make them slightly lighter. The helium does leak
out at a faster rate, but generally lasts long enough for a race.
Some will even use tires with latex (as opposed to butyl rubber)
tubes which also don't hold their pressure well.
You could try other inert (AKA "noble") gases like Neon, Argon,
Krypton, or Xenon. They do tend to be rather expensive though.
Some of these gases are used for welding purposes. Flood the
welding area with an inert gas (usually argon or argon/helium),
and the joint will be relatively oxygen free, which makes it
less brittle.
Christopher Green
The life of a racing tire is short enough that I'm not sure O2 at its
atmospheric concentration would have much of a chance to degrade it,
but that might be one reason. (Pure O2 in an overheated tire, though,
would be instant fireworks.)
The water vapor in air (has nothing to do with N2 vs. O2) is the other
big reason. N2 and O2 behave as more-or-less ideal gases, but water
doesn't: it condenses and vaporizes inconveniently at temperatures in
the range of interest.
Leakage wouldn't mean diddly, except as an opportunity for a salesman
to BS a consumer into an add-on sale. (We know tire salesmen are all
honest and expert, and none would never do a thing like that.) It's
actually the other way around: the atomic radius of N is *less* than
that of O for a well-known reason (to chemists, anyway) sometimes
called the "nitrogen hiccup", and the molecular diameter of N2 is
likewise less than that of O2. See, among other places,
http://www.madsci.org/posts/archives/Feb2003/1046354777.Ch.r.html for
an explanation of the nitrogen hiccup.
If you were running helium in the tires, leakage would be a more
interesting problem. Keeping helium contained is always a significant
engineering challenge.
--
Chris Green
Ignasi Palou-Rivera
> You use nitrogen in race tires because it's inert. Tires filled with
> pure oxygen would be a very_bad_thing.
>
> Race tires use "clean" Nitrogen gas - no water. Ever drained your air
> compressor? Water. From the moisture in the air. In NASCAR/F1 where
> you measure your pressure to the .5 pound the air needs to be the same
> for each tire - that's why they use nitrogen. Water throws a wrench
> into the consistency side of it.
You're contradicting yopurself. Inert and moisture don't have anything
to do with each other.
As far as pure oxygen I can't see what would be so bad. Sure they can
burn, but so can when filled with air. besides a tire pressure is not
so high. As far as scary try hydrigen...
> For anything else it's a waste of money. Heck, when was the last time
> you checked your tire pressure? Unless it was today... you're not
> anal enough for nitrogen.
Agreed
--
Ignasi.
(using SPAM trap e-mail address)
Ignasi Palou-Rivera
> Nitrogen isn't inert, although it's a lot less reactive than oxygen.
> If nitrogen were inert, we wouldn't have to worry about such things
> as NO2 emissions, and we wouldn't have people using NOS kits for
> drag racing.
What temperatire are we talking about here? You have to go pretty high
for nitrogen to have any kind of appreciable reactivity.
Ignasi Palou-Rivera
> Now I wasn't sleeping in High School or Collage. Different gases expand at
> different rates.
And what makes gases expand differently is the number of atoms per
molecule. Both oxygena dn nitrogen are diatomic, therefore their
expansion behavior is basically identical.
Ignasi Palou-Rivera
> Actually, I've been filling my tires with HYDROGEN for years. As it's
> lighter than air, I actually improve my mileage as a direct result of the
> 'lift' that I get from the hydrogen! Oh, the humanity!
Oh, what a "lift" that would be. Up, up, and away!
Nate Nagel
> "Alex Rodriguez" <ad...@columbia.edu> wrote in message
> news:ch7j9c$454$7...@newsmaster.cc.columbia.edu...
>
>>In article <3JednY7GEpK...@giganews.com>, nom...@spam.not says...
>>
>>
>>>I don't think anyone here is talking about pure oxygen.
>>
>>Does that mean they are also not talking about pure nitrogen? In which
>>case I want to know what they are talking about?
>
>
> First of all, air is 70% nitrogen.
>
> Pure nitrogen will be dry. Whether this is of benefit is questionable.
That is the *whole* benefit.
>
> Pure nitrogen will also expand less with changes in temperature. A
> non-issue for most of us.
Nope, both nitrogen and dry air follow the ideal gas law closely enough
to make no difference. The real problem is the water vapor in regular
old air straight out of the compressor. If you had a really good air
dryer on your shop air setup, there would be no advantage at all to
using pure N2.
nate
>
> I only use pure nitrogen when recharging gas shocks.
>
> -Jeff Deeney-
>
>
Threeducks
> "Alex Rodriguez" <ad...@columbia.edu> wrote in message
> news:ch7j9c$454$7...@newsmaster.cc.columbia.edu...
>
>>In article <3JednY7GEpK...@giganews.com>, nom...@spam.not says...
>>
>>
>>>I don't think anyone here is talking about pure oxygen.
>>
>>Does that mean they are also not talking about pure nitrogen? In which
>>case I want to know what they are talking about?
>
>
> First of all, air is 70% nitrogen.
>
> Pure nitrogen will be dry. Whether this is of benefit is questionable.
>
> Pure nitrogen will also expand less with changes in temperature. A
> non-issue for most of us.
Than what? Dry air? If so, the amount of expansion with changes with
temperature will be identical.
Threeducks
> "el Diablo" <nom...@spam.not> writes:
>
>
>>Now I wasn't sleeping in High School or Collage. Different gases expand at
>>different rates.
>
>
> And what makes gases expand differently is the number of atoms per
> molecule.
Wrong.
> Both oxygena dn nitrogen are diatomic, therefore their
> expansion behavior is basically identical.
>
PV = nRT. n= the number of MOLES of the gas, not number of atoms.
Ray
> Ray <r...@nospam.com> writes:
>
>>You use nitrogen in race tires because it's inert. Tires filled with
>>pure oxygen would be a very_bad_thing.
>>
>>Race tires use "clean" Nitrogen gas - no water. Ever drained your air
>>compressor? Water. From the moisture in the air. In NASCAR/F1 where
>>you measure your pressure to the .5 pound the air needs to be the same
>>for each tire - that's why they use nitrogen. Water throws a wrench
>>into the consistency side of it.
>
>
> You're contradicting yopurself. Inert and moisture don't have anything
> to do with each other.
No, I'm not. Two separate reasons. the whole point of using Nitrogen
is because air from an air compressor has a bunch of water vapor in it.
It makes the engineers pull their hair out because it doesn't
expand/contract in a nice uniform method... remember, we're talking
about guys who increase tire pressure .25 pound at a time and value .01
second per lap. Nitrogen is used because it's relatively inert so it's
not dangerous. Try filling your tires with pure oxygen or hydrogen or
propane...
To recap:
1-dry gas is used because water vapor causes inconsistency in lap times
and tire pressures.
2-nitrogen is uesd because it's available and won't go boom.
Ray
Ray
>> Pure nitrogen will also expand less with changes in temperature. A
>> non-issue for most of us.
>
>
> Than what? Dry air? If so, the amount of expansion with changes with
> temperature will be identical.
>
>>
EXACTLY. Nice and even and consistent. When the tires get hot the
pressure goes up, say 5psi. Today it's 5 psi. Tomorrow it's 5 psi.
When you use "wet" air, sometime's it's 5 psi, sometimes it's 3,
sometimes it's 8. Not consistent enough for a race car.
Jan Kalin
>Ray <r...@nospam.com> writes:
>> You use nitrogen in race tires because it's inert. Tires filled with
>> pure oxygen would be a very_bad_thing.
>>
>> Race tires use "clean" Nitrogen gas - no water. Ever drained your air
>> compressor? Water. From the moisture in the air. In NASCAR/F1 where
>> you measure your pressure to the .5 pound the air needs to be the same
>> for each tire - that's why they use nitrogen. Water throws a wrench
>> into the consistency side of it.
>
>You're contradicting yopurself. Inert and moisture don't have anything
>to do with each other.
>
>As far as pure oxygen I can't see what would be so bad. Sure they can
>burn, but so can when filled with air. besides a tire pressure is not
>so high. As far as scary try hydrigen...
Think Apollo 1. Pure oxygen at high pressures is very dangerous and can
make organic materials spontaneously combust at rooma temperatures.
Put an organic grease in the valves of an oxygen cylinder and watch the
exposion. Admittedly the pressures in the cylinder are higher, but I
wouldn't want to put pure oxygen under pressure in my tires.
--
/"\ Jan Kalin (male, preferred languages: Slovene, English)
\ / http://charm.zag.si/eng/, email: "name dot surname AT zag dot si"
X ASCII ribbon campaign against HTML in mail and postings.
/ \ I'm a .signature virus. Copy me to help me spread.
Don Stauffer
wrong with really dry air, either. It is water vapor that has the big
swing in pressure versus temp. It is just that it is hard to find a
source of truly dry air, while dry nitrogen sources are common. The
problem with damp air is the dew point of the air in the tire. If the
dew point of the air is within the range of ambient temperatures
expected, one has water condensing and evaporating in the tire as the
temp changes. Unless one is racing, however, the pressure changes
shouldn't bother anyone, so for normal road use, I can't see using
nitrogen. In racing on pavement, a pound of pressure can affect
handling.
Jeff Deeney wrote:
>
> First of all, air is 70% nitrogen.
>
> Pure nitrogen will be dry. Whether this is of benefit is questionable.
>
> Pure nitrogen will also expand less with changes in temperature. A
> non-issue for most of us.
>
> I only use pure nitrogen when recharging gas shocks.
>
> -Jeff Deeney-
--
Don Stauffer in Minnesota
stau...@usfamily.net
webpage- http://www.usfamily.net/web/stauffer
Metal Dave
> >Has anyone used nitrogen in non-low profile tires? I checked the pro's
> >& cons but haven't seen what it costs? It might even be good for the
> >common tires in trucks and family cars.
>
> I'd be interested in hearing too... I am having the tires on my vehicle
> replaced somewhere around the end of october and the tire place told me they
> use nitrogen instead of oxygen. He said the molecules are larger than
> oxygen and there is less likely to be a leak. That was the first time I
> heard about that and honestly wasn't sure if he was bullshiting me or not.
>
> Fwed
Trollometer off the charts! I've seen this thread before somewhere, with
the bit about larger molecules.
Dave
y_p_w
> y_...@hotmail.com (y_p_w) writes:
> > Nitrogen isn't inert, although it's a lot less reactive than oxygen.
> > If nitrogen were inert, we wouldn't have to worry about such things
> > as NO2 emissions, and we wouldn't have people using NOS kits for
> > drag racing.
>
> What temperatire are we talking about here? You have to go pretty high
> for nitrogen to have any kind of appreciable reactivity.
Combustion chamber temperatures. California Smog Check reports include
NO2 emissions levels.
Bacteria converts N2 gas to usable compounds at lower temps. Without
this, protein-based life forms wouldn't be sustainable.
<http://helios.bto.ed.ac.uk/bto/microbes/nitrogen.htm>
Inert gases don't typically react except under extreme conditions.
There are xenon compounds out there, but they're not common, and are
produced under extrem pressures. Argon gas is inert at high temps -
inert enough to use for TIG welding.
fweddybear
> Dave
Not that I read this newsgroup alot, but this was the first time I
happened to see it....My apologies if you feel I am trolling....it just so
happens I am in the market for new tires as well (found a set of Michelin
80,000 mile tires.. mounted, balanced, valve stems, free tire rotation, and
tire disposal for 117.00 each complete) and as I said in my post, i never
heard of nitrogen being put in tires... I guess I ought to step into the 21
century already huh?? lol
Have a great holiday weekend!!
Fwed
Jim
>--------------
>Alex
If you want VERY predictible changes in tire pressure with changes in
temp you want a dry gas. Any dry gas. N2 is relatively cheap and
available (more so than equiv dry air) and is safe for use in tires.
Air contains 79% N2, 20% O2, 1% other; AND H2O VAPOR. Take out the
water vapor and it's as good as N2 but it's just
easier/cheaper/available to use N2.
None of this means a thing unless you pull over regularly to measure
and record you tire pressures to determine what pressure profile gets
you to work faster.
--
Jim
B.B.
"C. E. White" <cewh...@mindspring.com> wrote:
>Bruce Chang wrote:
>
>> uh.. Nitrogen has an atomic number of 7 while Oxygen has an atomic number
>> of 8. With just that information, it would appear that oxygen molecules
>> would be bigger than nitrogen molecules. No one fills tires with pure
>> oxygen and the air we breathe is already mostly nitrogen anyhow.
>
>Actually the atomic radius of Nitrogen is larger than the
>atomic radius of Oxygen. Don't know why - I guess a physics
>major can explain the difference.
I'm not a physics major, but I remember a rambling explanation I
heard in class long ago. The size of an atom is determined by how many
electron shells it has and how many protons are in the nucleus. More
shells (determined by more electrons--a few electrons per shell) makes
for a larger atom while more protons in the nucleus make for a smaller
atom. Where they balance is the size of the atom.
On the periodic table each line of atoms represents one shell.
Hydrogen and Helium have the first shell, with two electrons possible.
Hydrogen has one proton, so one shell out, and one proton sucking it
back in. Helium has two protons, but still one shell, so that one shell
gets sucked in a little closer. Lithium has three protons to pull its
electrons back in, but it's on the second row and therefore has two
shells and so is larger than hydrogen.
Each line of the table is similar--the leftmost element is the
largest, and they get smaller as you move to the right. Going down a
row gives you a whole new shell, so the atom is bigger overall.
Francium (atomic number 87) is probably the largest atom unless
another row is going to be added.
>O2 is highly reactive. N2 is not reactive at all, so that
>might be one reason for using N2 instead of pure O2.
>However, the case for using N2 instead of air, which is 80%
>N2 is probabkly shaky for normal drivers (i.e., not racers).
>
>Ed
--
B.B. --I am not a goat! thegoat4 at airmail.net
AZGuy
wrote:
>Has anyone used nitrogen in non-low profile tires? I checked the pro's
>& cons but haven't seen what it costs? It might even be good for the
>common tires in trucks and family cars.
IT's going to be the next rage in consumer tires. Shops are in the
process of buying nitrogen generating systems and will be charging
around $4 per tire to fill them with nitrogen instead of air. The
touted benefits are little or no change in pressure with changes in
temperature and much lower seepage loss thru the tire carcass. Plus
less deterioration of the tire carcass due to oxidation caused by, of
course, the oxygen in air. The deterioration isn't a big issue for
consumer tires unless you are the little old lady in Pasadena who has
the same set of tires for 15 years. It IS a major consideration for
the BIG RIGs, many of which have already switched to nitrogen filled
tires. Reduced deterioration of the carcass means the carcass can be
retreaded more times before it's worn out or blows out. More uniform
pressure means reduced operating cost.
I predict many people will opt to pay for nitrogen in their consumer
tires if for no other reason then it greatly reduces the worry about
low tire pressure for people who don't often check tire pressure.
It's going to be a "safety" sales point. And when you are paying $500
for a set of tires will another $16 scare many people away?
--
Elbridge Gerry, of Massachusetts:
"What, sir, is the use of militia? It is to prevent the
establishment of a standing army, the bane of liberty. . .
Whenever Government means to invade the rights and liberties of
the people, they always attempt to destroy the militia, in order
to raise a standing army upon its ruins." -- Debate, U.S. House
of Representatives, August 17, 1789
JazzMan
>
> On 1 Sep 2004 13:00:56 -0700, rudyxh...@yahoo.com (Rudy Hiebert)
> wrote:
>
> >Has anyone used nitrogen in non-low profile tires? I checked the pro's
> >& cons but haven't seen what it costs? It might even be good for the
> >common tires in trucks and family cars.
>
> IT's going to be the next rage in consumer tires. Shops are in the
> process of buying nitrogen generating systems and will be charging
> around $4 per tire to fill them with nitrogen instead of air. The
> touted benefits are little or no change in pressure with changes in
> temperature and much lower seepage loss thru the tire carcass. Plus
> less deterioration of the tire carcass due to oxidation caused by, of
> course, the oxygen in air. The deterioration isn't a big issue for
> consumer tires unless you are the little old lady in Pasadena who has
> the same set of tires for 15 years. It IS a major consideration for
> the BIG RIGs, many of which have already switched to nitrogen filled
> tires. Reduced deterioration of the carcass means the carcass can be
> retreaded more times before it's worn out or blows out. More uniform
> pressure means reduced operating cost.
>
> I predict many people will opt to pay for nitrogen in their consumer
> tires if for no other reason then it greatly reduces the worry about
> low tire pressure for people who don't often check tire pressure.
> It's going to be a "safety" sales point. And when you are paying $500
> for a set of tires will another $16 scare many people away?
Ah yes, and perhaps we can sell them Tornados as well. :)
If the ad says it works, it must be right...
JazzMan
--
**********************************************************
Please reply to jsavage"at"airmail.net.
Curse those darned bulk e-mailers!
**********************************************************
"Rats and roaches live by competition under the laws of
supply and demand. It is the privilege of human beings to
live under the laws of justice and mercy." - Wendell Berry
**********************************************************
Don Stauffer
pressures. Relevant to this discussion.
AZGuy wrote:
>
>
>
> I predict many people will opt to pay for nitrogen in their consumer
> tires if for no other reason then it greatly reduces the worry about
> low tire pressure for people who don't often check tire pressure.
> It's going to be a "safety" sales point. And when you are paying $500
> for a set of tires will another $16 scare many people away?
> --
> Elbridge Gerry, of Massachusetts:
>
AZGuy
wrote:
The difference is that nitrogen DOES work better the air if you wish
to reduce pressure change with temperature and pressure loss over
time.
Marty Bose
<jimnaz...@cox.net> wrote:
> On Sun, 12 Sep 2004 11:03:57 -0500, JazzMan <No_...@airmail.net>
> wrote:
>
> The difference is that nitrogen DOES work better the air if you wish
> to reduce pressure change with temperature and pressure loss over
> time.
When we tried using nitrogen in our race car tires, it reduced the
pressure change by half, but ultimately wasn't worth the hassle. It
was more difficult to get all of the air out than it was to take the
air's expansion into account in the first place.
Marty
ceraboy
Some of you guys are really naive. The compostion of air at sea level
is nearly 80% nitrogen, with the balance mostly oxygen, and Argon (yet
another inert gas) coming in third around 1%. Remember your high
school chemistry, the ideal gas law PV = nRT, any change in temperature
will result in a change in volume. Taking out the 20% oxygen (even
though these gases in the tires are not ideal) is not going to negate
pressure increase with temperature or drop it by half. If you believe
the nitrogen fill is going to give you all these benefits, I am sure
you will find a way to make the results indicate just that (remember
cold fusion).
Metal Dave
> >Fweb
> >>Nitrogen Filled Tires
>
> >He said the molecules are larger than
> >oxygen and there is less likely to be a leak.
>
> >Like from a zillion to a few zillion to an inch or more.
> >Bob AZ
>
> I said that only because thats what the guy behind the counter selling
> the tires told me. After all, when you go anywhere to purchase products for
> your use, the salesperson you speak with should know their product and be
> informative about it.....he is the one you go to for advise. I also stated
The lesson that you shouldn't assume salespeople know anything about their
product is more important than anything regarding air vs. nitrogen you
might learn from this thread. Buy a pressure gauge and use normal air.
You'll be fine if you follow the instructions in your drivers manual
regarding tire pressure and maintenance. You'll have the added benefit of
being able to adjust your air pressure at any gas station without worrying
about having to find a nitrogen pump.
Note in the job ads for salespeople, most positions require *sales*
experience, not knowledge with a particular product. Think about the fact
that the salesperson's goal is to sell you something, not teach you
something, and about the fact that the salesperson might not know the
product well anyway. (It's even less likely they will know the fundamental
concepts underlying how a product function.) You should come to some
useful conclusions about exactly how much stock to put in any technical
"facts" told to you by a salesperson.
Of course there are exceptions but it's always a good idea to be cautious
with salespeople. I've had car salespeople display gross misunderstandings
of the features of different models in their product lines on numerous
occasions (or perhaps they just misunderstood the concept of telling the
truth).
Dave
fweddybear
> Dave
True.... a good lesson to learn about the salesperson not necessarily
knowing what they are selling....and I've known this for sometime as back in
the 80's when my roomate worked selling cars, electronics, and even
sandwiches.... (he worked at a deli...lol).
This is exactly why I expressed an interest to know what the difference
between an air filled tire was and a nitrogen filled tire. I believe I also
stated that in my posting...... it was the first time I heard about
something like that........ so by listening to the guy behind the counter, I
think... hmmmmmmmmmm.... can I believe this guy??
Then about two days later, I see the post from the first guy about nitrogen
filled tires... who was to know there would be so much discussion on this
topic?? I did find it interesting......and appreciate all the information
from this newsgroup, as I do with some of the other newsgroups I belong to.
I know I've learned alot for it!!!!
Fwed
Proctologically Violated©®
"ceraboy" <cer...@yahoo.com> wrote in message
news:xn0dn7bo...@news.cle.sbcglobal.net...
Cold Fusion indeed!!
Assolutely correct:
The pressure change w/ all nitrogen should be *identical* to
reg. air.
Even if it there were a diff, you would have to factor that
poss. diff by 0.2, the component of Ox in air. So even in that case, 50%
reductions in pressure variation would be impossible.
And, the pressure change should not be all that much anyway. P2
= P1*(T2/T1), where T is in Kelvin, and T1 is approx = 300. And how hot
does the air get? If it got 30 C hotter, that would be only a 10% change.
And 30 C is a lot. Also, rubber is a very good insulator, so you can't go
by the surface temp of the tire, either.
Last time I looked at a set of Michelins w/ nearly 100K miles on
them, it seemed like the damage was on the outside, not the inside!
----------------------------
Mr. P.V.'d
formerly Droll Troll
TE Cheah
In your climate, air is already dry, so dry nitrogen* may make a smaller
difference to you there than * can here where air is very humid.
1 tyre shop here is confident enough that users will like the benefits, &
offers for 4 days free *. I was amazed by this confidence so took their
offer : got * pumped into 4 Michelin "green" tyres ( 205 & 195/65R15
@2.3kg/cm² ) with the lowest rolling resistance (rr) I know & already
aligned to parallel ( no toe-in / out ).
1 of the shop's claims is a 2% drop in rr, but I think my rr dropped by
3-5% ( based on my accord's minimum tow force needed ), vehicles with
higher rr may feel nothing. My 6½" alloy wheels are now much cooler,
& receive less shock ( over bumps ) than before ( just as told by this shop
's staff ).
I don't have a electron microscope to see atoms, I suspect these 3
benefits come from *'s lower molecular friction than those of other
gases. Has any physicist studied & compared gases' molecular friction ?
Bob Paulin
TE Cheah <n...@spam.biz> wrote in article <41894...@news.tm.net.my>...
>
> with the lowest rolling resistance (rr) I know & already
> aligned to parallel ( no toe-in / out ).
Zero static toe WILL result in dynamic toe-in/out - depending on the drive
configuration of the vehicle. - due to the takeup of allowable
manufacturing tolerances in the steering components as the wheels roll
ahead.
A RWD will toe-out and a FWD will toe-in under dynamic conditions.
Manufacturing engineers understand that and develop a recommend toe-in/out
specification that is designed to allow for those steering component
tolerances, which results in the wheels pointing straight-ahead when they
roll.
If you have zero static toe, then your tires are NOT parallel and pointing
straight-ahead when rolling......it is that simple.
Ted Mittelstaedt
"TE Cheah" <n...@spam.biz> wrote in message news:41894...@news.tm.net.my...
molecular friction?!?! WTF?
I really doubt your observations as you have posted nothing regarding your
testing methodology. However, assuming that what your seeing is the case,
a much easier explanation is that dry nitrogen expands less than wet air, in
the presense of heat.
I'm no chemist and I'm too lazy to look up the expansion differences to do
the math, but I would hypothesis that your previously "wet air" filled tires
had a higher tire pressure when you got them warmed up. That would account
for the 'less shock' observation. Perhaps with your tires construction,
overinflation
makes them run hotter as well.
If you forgot to measure warm tire pressure of the different fills, your
observations
are pretty worthless I'm afraid.
Ted
Bob Paulin
TE Cheah <n...@spam.biz> wrote in article <41894...@news.tm.net.my>...
>
> with the lowest rolling resistance (rr) I know & already
> aligned to parallel ( no toe-in / out ).
ed
Brian
conditions. Ackerman adds toe-out as soon as the wheels are turned, and you
can get a condition where the car seems to wander, and seems to turn in too
fast when you initiate a turn. Also, if bump-steer gives you toe-out under
bump, then the car will get darty under braking, and might get very darty
under a panic stop condition.
Racers tune their cars using stuff like this, and often run static toe-out
to get the car to point well at the beginning of a turn. But racers also
corner under far more aggressive tire-slip angles and load conditions where
actual toe-in/out makes less difference in steady state cornering.
Brian
"Bob Paulin" <ra...@mint.net> wrote in message
news:01c4c283$3b98f200$a1a7c3d8@race...
TE Cheah
| > specification that is designed to allow for those steering component
| > tolerances, which results in the wheels pointing straight-ahead when they
| > roll.
auto-correct accurately @ every speed ?
| > If you have zero static toe, then your tires are NOT parallel and pointing
| > straight-ahead when rolling
This may be true for certain cars of yours, not for my '90 accord (4ws,
FWD ) ; rr was far higher with the 3mm rear wheels toe-in prescribed, on
highway @ 110 or 60 kph.
Bob Paulin
> TE Cheah <n...@spam.biz> wrote in article <418c6...@news.tm.net.my>...
> This may be true for certain cars of yours, not for my '90 accord (4ws,
> FWD ) ; rr was far higher with the 3mm rear wheels toe-in prescribed, on
> highway @ 110 or 60 kph.
>
You've got yourself quite a unique car there, Bunky!
All the FWD cars I have ever dealt with - Honda Accords included - went to
dynamic toe-in under straight acceleration - which is why FWD alignment
specs usually call for static toe-out when aligning them......
.....but, since your response seems to suggest that you already know it
all, I wonder why you even asked for advice in the first place?!?!
Bob Paulin
TE Cheah <n...@spam.biz> wrote in article <418c6...@news.tm.net.my>...
> Cars can move @ different speeds, how can wheels with fixed toe-in/out
> auto-correct accurately @ every speed ?
>
There isn't a different toe spec for different speeds. Straight ahead is
what you are seeking when the car is going straight.
Once the tolerances/clearances in the steering linnkage have been taken up,
the wheels will not toe-in/out any further, and will remain pointing
straight ahead at all speeds.