OT: Nitrogen filled tires

[Rich Grise]

You didn't see the science guy on Leno a few weeks back? Fish tank full of
sulfur hexaflouride with an aluminum foil boat floating in air. Then they
took a stun gun shooting sparks and put it into the tank and all sparking
stopped. Leno took a lungful and instead of the high pitched helium talk
turned into Barry White. Some other neat tricks to light candles.

http://en.wikipedia.org/wiki/Sulfur_hexafluoride

Aww, c'mon! I was expecting a link to a clip! )-;

Thanks,
Rich

 

[Bobo The Chimp]

Next time, insist on Helium. Places that fill tires with Helium instead
of Nitrogen always have lots of repeat customers, so it *must* be good!

A related question: I am about to install new speakers in my convertible.
Should I point them to the rear for better gas mileage, or point them up
for better traction? :0

Point them to the sides, so you can annoy the maximum possible number of
people, and maybe you can earn your way into the ranks of the other
Spiggers.

 

[Bobo The Chimp]

Why not just add a refrigerated dryer, molecular sieve or desiccant
upstream of the nozzle or tank and remove the moisture from the air
source?

Duh! Because then they wouldn't be able to to charge the idiots $100.00
for air!

 

[Rich Grise]

Then why do high-end race cars run N2?

Because it doesn't support combustion.

Hope This Helps!
Rich

 

[Rich Grise]

It would be useful if Drexan's cost per nitrogen fill-up were given -
then, one could determine the break-even time, if any, for the whole
fleet, using nitrogen fill-ups vs. the cost of the additional fuel
consumed. Since this information is not given, though, I'm going by the
$100 per fill-up quoted in the Car Talk article... and, clearly, there, it
is not worth it for the individual user. $100 can buy at least two
fill-ups for my Camry (though, probably not for an SUV...)

Geez! It is irrelevant what gas you use. You can use air, you can use N2,
you could use argon, helium, SF6, CO2 - it doesn't matter. ANY gas obeys
the same gas laws: PV=TK.

The pressure thing is about the wear that's exacerbated by the flexing
of the rubber, which heats it up and weakens it. A tire is designed to
accomodate a certain footprint.

Of course, it _is_ a good idea to limit the oxygen if you expect your
tires to reach 500F. ;-)

And probably not a good idea to use methane or propane or ether,
etc. =:-O

Anybody who can get a hundred bucks out of you for changing the air in
your tires obviously saw you coming. ;-)

Heck, come over to my place - we've got an account with AirGas and with
FiveStar Gas & Gear - I can get you any gas you want! Wanna fill your
tires with argon? I can do that - it's even _more_ inert than plain
nitrogen, and I'll only charge you $75.00 for an "air change". >:->

See? You've just saved $25.00 - you can afford a pizza! ;-)

Cheers!
Rich

 

[Glen Walpert]

You could fill a tire with a high-molecular-weight gas, like a freon
or something, and it might leak less.

The mafia has been known to put freon in the tires or their
"customers" who get behind on their "insurance" payments. Properly
done it guarantees a blowout after a while at highway speeds.

I used to fill my bicycle tires with propane, for that reason and to
avoid pumping. Of course, that has at least two tricky side effects.

Too high a vapor pressure at typical ambient temperatures, hard to get
much liquid in there, try freon .

 

[Don Klipstein]

Snowstorm? Do they still have those? ;-)

Yes, global warming needs to progress another 1-1.5 degrees C/K (without
shifting the Gulf Stream) in order for the USA's "Northeast Corridor" to
get much less of those.

NYC and Boston had single-storm snowfall records in the past 2-3 years
or so, while Philadelphia's biggest snowstorm and snowiest winter in the
past 130 years were the "Blizzard of 1996" and the 1995-1996 winter
respectively.

Maybe around 2020 it will start snowing less in the USA's "Northeast
Corridor". And I do mean less, as opposed to "not at all".

Even if/when global warming gets to about 2 degrees C/K above the
1930-1980 average, I still expect snowstorms in the Appalachian Mountains
from SW North Carolina and nearby areas of Tennessee upward, as well as in
the Great Lakes area, and in higher mountain areas in western USA and the
"Canadian Rockies".

Heck, 2 degrees C/K of global warming, even if that much close to the
equator, will only move upward the snowline at Mt. Kilimanjaro (NE
Tanzania, Africa) maybe 1000-1100 feet or 300-350 meters upwards. I
also expect that such an extent of global warming will not do much against
snow impact upon the Himilayas above roughly 18,000-19,000 feet or 5,500
to 5,800 meters or so above sea level.

- Don Klipstein ([email protected])

 

[Don Klipstein]

Yeah, sure, if nR = K. ;-)

Do you mean n and R and product thereof are constant?

I do suspect that such assumptions are reasonable, and argument
otherwise is on basis of non-ideal-gas, such as humid air subject to
condensation of water vaor content. Otherwise on basis of V being
non-constant otherwise most-likely on O2 being removed by reaction with
container surface(s).

- Don Klipstein ([email protected])

 

[ChairmanOfTheBored]

Things seem pretty slow in SED today, so let's talk about "Hot Air".
(Like the kind in your tires.)

Every so often I read something like this:
http://fleetowner.com/news/topstory/fleet_nitrogren_beats_air/
suggesting Nitrogen is better than air for improved mileage, lower
tire wear, reduced Global Warming, etc....

The trick is you fill your tires with Nitrogen instead of compressed
air.

Huh?! Air is 78% (or so) Nitrogen anyway.
Is there anything to this, or is this a classic signal-to-noise
problem...??
Notice too that the article does not mention any service stations so
equipped...

-mpm

Perhaps the beads of the rim oxidize less on the Nitrogen filled
series, and thereby leak down less, making the stats for those vehicles
batter. Maybe even the valves degrade less.

So, if that is the reason, then I believe the study.

 

[ChairmanOfTheBored]

It would be useful if Drexan's cost per nitrogen fill-up were given -
then, one could determine the break-even time, if any, for the whole
fleet, using nitrogen fill-ups vs. the cost of the additional fuel
consumed. Since this information is not given, though, I'm going by
the $100 per fill-up quoted in the Car Talk article... and, clearly,
there, it is not worth it for the individual user. $100 can buy at
least two fill-ups for my Camry (though, probably not for an SUV...)

Michael

CarTalk is likely full of shit. It does NOT cost that much ($100 per
fill) to have a ten Lb tank of Nitrogen at 3000 psi on each truck, with a
regulator and means for the driver to maintain his tires with it.

You are one gullible fucker, fucker.

 

[ChairmanOfTheBored]

You could fill a tire with a high-molecular-weight gas, like a freon
or something, and it might leak less.

I used to fill my bicycle tires with propane, for that reason and to
avoid pumping. Of course, that has at least two tricky side effects.

KaBang!

 

[ChairmanOfTheBored]

"suck out the _old_ N2..."

Bwahahahahahaha!

Must be Slowman's kid ;-)

...Jim Thompson

OK, asshole... They DRAW out as much of the "old" gas as they can, then
FLUSH the cavity with fresh N2, THEN seal the beads and fill with N2.

Still, unless done in a vacuum chamber, some "air" is going to get in.

 

[ChairmanOfTheBored]

"dead inert"? a *fluoride* compound? It even sounds toxic.

Even the sulfur part sounds bad, but he is right as far as rubber and
metals go.

 

[ChairmanOfTheBored]

Next time, insist on Helium. Places that fill tires with
Helium instead of Nitrogen always have lots of repeat
customers, so it *must* be good!

A related question: I am about to install new speakers in
my convertible. Should I point them to the rear for better
gas mileage, or point them up for better traction? :0

It's a sine wave, so you lose just as much as you claim to gain in each
and every cycle.

Put wings on 'em.

Chitty Chitty Bang Bang...

 

[ChairmanOfTheBored]

Google it and see. If you don't think fluoride compounds
can be inert, I would suggest you consider Teflon....

Bob M.

3M makes a product called "Fluorinert".

The medical industry makes "LiquiVent" for human medical procedural
use. A highly oxygenated perfluorocarbon fluid.

The key here is the lack of them being "chlorinated" fluorocarbons.

Cl is bad...

 

[ChairmanOfTheBored]

On Fri, 21 Sep 2007 14:23:24 -0700, John Larkin


Whenever my tires get low, I bring it in (no appointment, no charge)
and they suck all the old N2 out and refill with fresh N2, and I drive
away.

They claim the tire pressure is less affected by the tire temperature,
too, which may account for the 3% fuel savings in that article.

PV = nRT for any gas, right?

John

"suck out the _old_ N2..."

I have that done twice a year to my wife's car. When I get back home
it'll be past time to replace the summer air with winter air[*]. If
we get an early snow storm, I'll be a dead man. :-(
.

Bwahahahahahaha!

Must be Slowman's kid ;-)

[*] The air gets changed along with the rubber; no additional
charge. ;-)

I put Helium in my tires so the car floats.

Yeah, right...

All four tires add up to a grand total of one pound of less downward
force, and that only at sea level. Whoopie!

 

[ChairmanOfTheBored]

Things seem pretty slow in SED today, so let's talk about "Hot Air". (Like
the kind in your tires.)

Every so often I read something like this:
http://fleetowner.com/news/topstory/fleet_nitrogren_beats_air/ suggesting
Nitrogen is better than air for improved mileage, lower tire wear, reduced
Global Warming, etc....

The trick is you fill your tires with Nitrogen instead of compressed air.

Huh?! Air is 78% (or so) Nitrogen anyway. Is there anything to this, or
is this a classic signal-to-noise problem...??
Notice too that the article does not mention any service stations so
equipped...

When I was in the USAF, at one point I worked on the SR-71 Blackbird
http://www.google.com/search?hl=en&q="sr-71+blackbird"

and they used dry nitrogen in its tires. But the reason, they told me,
didn't have anything to do with gas mileage, it was so that when it
lands at about 300 MPH, the tires don't explode and burn. Hot rubber
and oxygen can get a little volatile.

But, for a car, the only difference I can think of would have to do
with condensation, and just using dry air should alleviate any risk
in that area.

IOW, if somebody's making a claim like that, and expecially[SIC] if
they're trying to sell you something (like nitrogen), then they're
just blowing smoke up your ears, so to speak.

Hope This Helps!
Rich

Better...

http://www1.dfrc.nasa.gov/Gallery/Photo/Fleet/HTML/EC97-44165-149.html

I particularly like the X-36, and wish it had been chosen over the
YF-22, or at least both of them!

 

[ChairmanOfTheBored]

Aww, c'mon! I was expecting a link to a clip! )-;

Thanks,
Rich

 

[ChairmanOfTheBored]

Geez! It is irrelevant what gas you use. You can use air, you can use N2,
you could use argon, helium, SF6, CO2 - it doesn't matter. ANY gas obeys
the same gas laws: PV=TK.

The pressure thing is about the wear that's exacerbated by the flexing
of the rubber, which heats it up and weakens it. A tire is designed to
accomodate a certain footprint.

Of course, it _is_ a good idea to limit the oxygen if you expect your
tires to reach 500F. ;-)

And probably not a good idea to use methane or propane or ether,
etc. =:-O

Anybody who can get a hundred bucks out of you for changing the air in
your tires obviously saw you coming. ;-)

Heck, come over to my place - we've got an account with AirGas and with
FiveStar Gas & Gear - I can get you any gas you want! Wanna fill your
tires with argon? I can do that - it's even _more_ inert than plain
nitrogen, and I'll only charge you $75.00 for an "air change". >:->

See? You've just saved $25.00 - you can afford a pizza! ;-)

Cheers!
Rich

Nowadays... a *small* pizza.

 

[ChairmanOfTheBored]

The mafia has been known to put freon in the tires or their
"customers" who get behind on their "insurance" payments. Properly
done it guarantees a blowout after a while at highway speeds.


Too high a vapor pressure at typical ambient temperatures, hard to get
much liquid in there, try freon .

The static pressure of R-12 is almost the same as the ambient temp when
around 70F. This is one way of telling how full your R-12 tank is. It
is no longer in use in the US.

At other temps, I am sure it isn't linear, but the stuff changes
pressure a LOT with temperature.