Nitrofill Your Car Tires

[staunch]

I brought my vehicle in for service. The mechanic and I are discussing tire pressure. He says have you ever considered replacing the air in your tires with nitrogen, I immediately think of the joke, Blonde walks into garage and asks the mechanic to replace the winter air in her tires with summer air. Any way, I asked how they purge the air that is already in the tire before it is pressurized with nitrogen. Do they suck all the air out before adding the nitrogen? This is what I can remember him saying. The tire is deflated to 5 pounds and then inflated back to the proper setting. The tire is then deflated a second time to 5 pounds of pressure, and again reinflated back to the proper inflation, this takes the oxygen out. The cost about $30.00 with tax. I may have omitted a few details. I did a Google on the product http://nitrofill.com/ consumer blog http://blogs.consumerreports.org/cars/2007/10/tires-nitrogen-.html
The hype.
For decades nitrogen has been the choice for tire inflation of NASCAR, Formula One, The Tour de France, the US Military and many other applications where safety and economy are paramount concerns. Only the high cost and complexities of generating or storing nitrogen have kept it out of reach of the general public. Recent advances in nitrogen production technology have made on-site generation economically viable for the automotive service industry.
• In 7 million miles of truck tire testing, nitrogen inflated tires lasted longer.
• Tire failures were reduced by 50%
• Tread life was increased by 25-30%
• Improves steering
• Improves handling
• Improves braking
• Reduces chance of tire failure
• Dramatically slows pressure loss from permeation
• Improves fuel economy
• Reduces tire oxidation
• Eliminates interior wheel corrosion
• Reduces running temperatures
• Decreases false alarms and activation of Tire Pressure Monitoring Systems

All of the benefits of proper tire inflation can be achieved with normal air pressure unless you are a NASCAR driver doing 150 laps at 200mph.
They claim your tires will oxidize slower if you use the product. They must mean the oxidation of the interior of the tire surface; the exterior is still in contact with normal air. I do believe rubber will oxidize at some point in time. I believe my tire will wear out before that happens. So if you maintain tire pressure using free air I can not see any oxidation occurring. Increase in fuel economy, Improves steering, reduced tire failure by %50 Improves braking and handling. Some of these claims may involve some chemistry and physics knowledge. So I decided the next time I bring my car for service I will tell the mechanic I used Nirtoglycerine instead of Nitrogen. I had a blast! :) Then I accidently used Nitrous oxide. That was a laugh! :)

[rwguinn]

I brought my vehicle in for service. The mechanic and I are discussing tire pressure. He says have you ever considered replacing the air in your tires with nitrogen, I immediately think of the joke, Blonde walks into garage and asks the mechanic to replace the winter air in her tires with summer air. Any way, I asked how they purge the air that is already in the tire before it is pressurized with nitrogen. Do they suck all the air out before adding the nitrogen? This is what I can remember him saying. The tire is deflated to 5 pounds and then inflated back to the proper setting. The tire is then deflated a second time to 5 pounds of pressure, and again reinflated back to the proper inflation, this takes the oxygen out. The cost about $30.00 with tax. I may have omitted a few details. I did a Google on the product http://nitrofill.com/ consumer blog http://blogs.consumerreports.org/cars/2007/10/tires-nitrogen-.html
The hype.
For decades nitrogen has been the choice for tire inflation of NASCAR, Formula One, The Tour de France, the US Military and many other applications where safety and economy are paramount concerns. Only the high cost and complexities of generating or storing nitrogen have kept it out of reach of the general public. Recent advances in nitrogen production technology have made on-site generation economically viable for the automotive service industry.
• In 7 million miles of truck tire testing, nitrogen inflated tires lasted longer.
• Tire failures were reduced by 50%
• Tread life was increased by 25-30%
• Improves steering
• Improves handling
• Improves braking
• Reduces chance of tire failure
• Dramatically slows pressure loss from permeation
• Improves fuel economy
• Reduces tire oxidation
• Eliminates interior wheel corrosion
• Reduces running temperatures
• Decreases false alarms and activation of Tire Pressure Monitoring Systems

All of the benefits of proper tire inflation can be achieved with normal air pressure unless you are a NASCAR driver doing 150 laps at 200mph.
They claim your tires will oxidize slower if you use the product. They must mean the oxidation of the interior of the tire surface; the exterior is still in contact with normal air. I do believe rubber will oxidize at some point in time. I believe my tire will wear out before that happens. So if you maintain tire pressure using free air I can not see any oxidation occurring. Increase in fuel economy, Improves steering, reduced tire failure by %50 Improves braking and handling. Some of these claims may involve some chemistry and physics knowledge. So I decided the next time I bring my car for service I will tell the mechanic I used Nirtoglycerine instead of Nitrogen. I had a blast! :) Then I accidently used Nitrous oxide. That was a laugh! :)
The only difference between "Free air" and pure Nitrogen is the water vapor content.
When you are performing such that 1/4 psi of air pressure makes a significant difference, then Nitrogen is the thing to use-because it is dry.
All gasses follow the same expansion under temperature changes. The exception is vater vapor--and at 200MPH, it can make a difference. Otherwise, ots a waste of money...
Tirese are not a 0 maintennence item, an many people seem to think

[jmercer]

Moved here for (what I hope) are obvious reasons.

[DavidS]

The only difference between "Free air" and pure Nitrogen is the water vapor content.
When you are performing such that 1/4 psi of air pressure makes a significant difference, then Nitrogen is the thing to use-because it is dry.
All gasses follow the same expansion under temperature changes. The exception is vater vapor--and at 200MPH, it can make a difference. Otherwise, ots a waste of money...
Tirese are not a 0 maintennence item, an many people seem to think
Well, not quite...

The greater oxygen content of air and its implications for the elastomer's durability would be a more convincing argument. "More convincing" in the same sense that St. Augustine is "more lofty" than Bermuda grass, IMO; internal oxidative degradation is unlikely to have time to hurt you in a 200MPH performance application, or to degrade performance meaningfully in a more mundane application.

At the temperatures and pressures of interest for pneumatic tires, it's reasonably true that all gases "follow the same expansion under temperature changes". Water vapor, however, is hardly an exception; at tire conditions it's as close to ideal gas behavior as the nitrogen, oxygen (argon, et al...) in air, at least to within a very small fraction of a psi; if you have data to the contrary, I'd love to see it.

The phase transition from condensed liquid water might be an issue, but sufficiently drying air to put its (compressed) dewpoint temperature far below high-performance operating conditions doesn't require cutting-edge technology. The question then is probably whether it's more convenient to dehumidify your compressed air or just buy cryogenically-dry, readily-available, nitrogen already compressed into a very portable bottle at a cost negligible in comparison to the rest of your racing kit.

I do concur with you, however, that modern tires are underappreciated technological marvels too often neglected.

[Tokenconservative]

I brought my vehicle in for service. The mechanic and I are discussing tire pressure. He says have you ever considered replacing the air in your tires with nitrogen, I immediately think of the joke, Blonde walks into garage and asks the mechanic to replace the winter air in her tires with summer air. Any way, I asked how they purge the air that is already in the tire before it is pressurized with nitrogen. Do they suck all the air out before adding the nitrogen? This is what I can remember him saying. The tire is deflated to 5 pounds and then inflated back to the proper setting. The tire is then deflated a second time to 5 pounds of pressure, and again reinflated back to the proper inflation, this takes the oxygen out. The cost about $30.00 with tax. I may have omitted a few details. I did a Google on the product http://nitrofill.com/ consumer blog http://blogs.consumerreports.org/cars/2007/10/tires-nitrogen-.html
The hype.
For decades nitrogen has been the choice for tire inflation of NASCAR, Formula One, The Tour de France, the US Military and many other applications where safety and economy are paramount concerns. Only the high cost and complexities of generating or storing nitrogen have kept it out of reach of the general public. Recent advances in nitrogen production technology have made on-site generation economically viable for the automotive service industry.
• In 7 million miles of truck tire testing, nitrogen inflated tires lasted longer.
• Tire failures were reduced by 50%
• Tread life was increased by 25-30%
• Improves steering
• Improves handling
• Improves braking
• Reduces chance of tire failure
• Dramatically slows pressure loss from permeation
• Improves fuel economy
• Reduces tire oxidation
• Eliminates interior wheel corrosion
• Reduces running temperatures
• Decreases false alarms and activation of Tire Pressure Monitoring Systems

All of the benefits of proper tire inflation can be achieved with normal air pressure unless you are a NASCAR driver doing 150 laps at 200mph.
They claim your tires will oxidize slower if you use the product. They must mean the oxidation of the interior of the tire surface; the exterior is still in contact with normal air. I do believe rubber will oxidize at some point in time. I believe my tire will wear out before that happens. So if you maintain tire pressure using free air I can not see any oxidation occurring. Increase in fuel economy, Improves steering, reduced tire failure by %50 Improves braking and handling. Some of these claims may involve some chemistry and physics knowledge. So I decided the next time I bring my car for service I will tell the mechanic I used Nirtoglycerine instead of Nitrogen. I had a blast! :) Then I accidently used Nitrous oxide. That was a laugh! :)

Sounds good.

One drawback: currently, if a tire on one of my cars is a bit low, I run by the convenience station and fill it for $.50.

I'd have to pay $30 each time I am down 5# of pressure?

Tokie

[Autolite]

Working on aircraft, all aircraft tires were always filled with nitrogen. The oxidation issue was the only things that was a concern. Being that ambient air is almost 80% nitrogen anyway, I can't really see a huge advantage for passenger car use ...

[Prometheus]

I had my tires filled with nitrogen, but only because the shop where I bought them and had them installed threw in nitrogen-filling with unlimited refills for just $5 for all four tires. It's been 3 years, and I have not had any problems, but I've not noticed any definite advantages either. I make a habit of checking tire pressure before long trips, and have never needed to add any, so perhaps there's something to the claim that nitrogen reduces leaking. On the other hand, I switch between snow tires and all-season tires twice a year, and the shop re-fills them to proper pressure then, so I can't say whether they'd leak after more than about 6 months.

[JJM]

Most of the claims for using nitrogen inflation seem bogus, I don't wish to address each claim.

However, one can read about the propensity for leakage in any introductory chemistry text. The lower formula weight gas leaks faster. Nitrogen (28) would leak faster than oxygen (32) by a trivial amount.

Steel wheels last decades, without significant oxidation, with air-inflation (as long as the tire is left on to limit exposure to liquid water).

On the other hand; under-inflated, overworked tires can overheat to the point of catching fire. Purging the oxygen from the interior of a tire that could be extremely stressed (race cars, airplanes, big rigs) may lend a safety margin to this. I don't know. I do know that a lot of things that one would think practitioners know are wrong. Have you ever watched a (US) football game and noted all the athletes that think a bit of adhesive tape applied to their nose helps them breath better?

[casebro]

Re: 'dry air'- The compressing dries most of the water out. It condenses under pressure, and falls to the bottom of the tank, long before it gets to your tires. So compressed sir should have a waaay low moisture content, if the stations drain the water from their tanks daily.

But on a related note as the OP, why do airplanes have a harder time taking off in hot air? Gas viscosity does not change over a, say, 40 degree range. Thinner air, not. Lower PPO?

[Olowkow]

Here is the opinion of Click and Clack on Car Talk:

http://www.cartalk.com/content/columns/Archive/2005/February/02.html

[JJM]

Here is the opinion of Click and Clack on Car Talk:

http://www.cartalk.com/content/columns/Archive/2005/February/02.htmlBased on the fact they mostly agree with me, those guys are geniuses. But I would like to see support for:TOM: Pure nitrogen has a couple of advantages. One is that it expands and contracts less under hot and cold temperatures than a mixture of nitrogen, oxygen and water vapor. [Italics added, JJM]The relevant gas law is PV=nRT. (That is, the variables are Pressure, Volume, amount (n) and Temperature; R is a constant.) To a good approximation, the identity of the gas is irrelevant to its expansion/contraction. While there are small corrections to this depending on the identity of the gas, I doubt they are significant (in this case), even in race cars.

[Olowkow]

I was wondering about that one too.

From:
http://galileo.phys.virginia.edu/classes/152.mf1i.spring02/ThermProps.htm

In 1702, Amontons discovered a linear increase of P with T for air, and found P to increase about 33% from the freezing point of water to the boiling point of water.

That is to say, he discovered that if a container of air were to be sealed at 0°C, at ordinary atmospheric pressure of 15 pounds per square inch, and then heated to 100°C but kept at the same volume, the air would now exert a pressure of about 20 pounds per square inch on the sides of the container. (Of course, strictly speaking, the container will also have increased in size, that would lower the effect—but it’s a tiny correction, about ½% for copper, even less for steel and glass.)

Remarkably, Amontons discovered, if the gas were initially at a pressure of thirty pounds per square inch at 0°C, on heating to 100°C the pressure would go to about 40 pounds per square inch—so the percentage increase in pressure was the same for any initial pressure: on heating through 100°C, the pressure would always increase by about 33%.

Furthermore, the result turned out to be the same for different gases!

[ponderingturtle]

Re: 'dry air'- The compressing dries most of the water out. It condenses under pressure, and falls to the bottom of the tank, long before it gets to your tires. So compressed sir should have a waaay low moisture content, if the stations drain the water from their tanks daily.


I am not so sure, I know we have problems with water getting into our compressed air lines at work. Well water and oil.

So I am not sure that the station would have cleaner air.

[DavidS]

Re: 'dry air'- The compressing dries most of the water out. It condenses under pressure, and falls to the bottom of the tank, long before it gets to your tires. So compressed sir should have a waaay low moisture content, if the stations drain the water from their tanks daily.
Well... not quite, at least not without some specificity about what you mean by "moisture content".

While it's true that ordinary compression and subsequent aftercooling to ambient temperature often condenses water that was originally vaporized in the pre-compression air, that in fact proves the opposite -- the compressed air is then demonstrably at its dewpoint temperature, fully saturated with water at that pressure (and temperature). That is, the compressed air is then at 100% relative humidity and will condense more liquid water on further isobaric cooling. That's why draining condensate from shop air systems is important: any slightly cool low spot will collect condensate, which could cause local corrosion, which could weaken the containment of the energy stored in the compressed air, which could break loose and do Bad Things to people and possessions around at the time.

At ordinary shop-compressor pressures, water vapor in air is essentially an ideal solution of ideal gases, and the air's "true gases" (nitrogen, oxygen, et al) are essentially immiscible in liquid water. The partial pressure of water vapor and concentration of water (mass or moles per unit volume) in such compressed air depends on temperature alone and will be *higher* after the compression/aftercooling/condensation/drainage step than it was before the compression (unless the precompression air was already at 100% RH and/or hotter than the compressed/cooled air).

Now, after draining away the condensate that "wet" compressed air does contain less mass of water per mass of "dry" air, and any pressure reduction (expansion) will proportionately lower the partial pressure of water vapor and (presuming no cooling) correspondingly reduce the dewpoint temperature and relative humidity. At some point along expansion air back to its initial temperature and pressure it will in fact be "drier" than it had been in both concentration (mass of water per unit volume) and compositional (mass of water per mass of mixture) senses; its relative humidity and dewpoint temperature will be lower. Whether that point occurs at a pressure above or below the tire's inflation pressure depends on the details of the process, particularly the temperatures involved and how much higher was the pressure at which condensate was drained.

[DavidS]

I am not so sure, I know we have problems with water getting into our compressed air lines at work. Well water and oil.
Then I suggest your shop air system is at least one of: poorly designed, poorly maintained, poorly operated, and/or a safety hazard.

A wet air system can easily corrode a tank or line to failure and turn itself into rocket-propelled projectiles or pipe whips. If it's wet enough to annoy you, I strongly suggest you raise safety flags until somebody trained in pneumatic arts assures you it's safe. Dropping names of attorneys or mentioning OSHA might not be a bad idea.

As I stated above, without post-compression dehumidification equipment it may not be possible to eliminate water condensation from the compressed air system. That dessication equipment may not be economically practical, especially for a small shop.

The next best thing would be to manage the condensed water so it doesn't collect and cause corrosion that could weaken a tank or line to fail at the worst possible time, or gather into slugs of liquid to damage pneumatic tools or spray gunk on target projects. I'm no expert here, but the usual methods are:

-- Provide enough storage for most post-compression cooling and condensation to occur in (or before) a tank where the condensate can be conveniently and frequently drained away

-- Avoid low spots where condensate can accumulate in piping runs, and provide condensate storage "drip legs" and drain valves at any such spots.

-- FREQUENTLY blow/drain any accumulated condensate out of the system. I can't imagine any good reason this isn't somebody's designated chore for the start and end of every single shift or workday.

Your oil problem may be another matter. It may be intentional to lubricate pneumatic tools, or it may be "leakage" from the compressor's own lubrication. Either way, if it's excessive enough to cause problems something needs fixing; a clapped out compressor may be leaking too much oil, the lubrication oil mist system may be injecting too much, or those might be fine but lack of drainage lets oil accumulate in the lines.

This is a legitimate safety concern. Doing it right is neither rocket science nor prohibitively more expensive or difficult than doing it wrong. Somebody with specific expertise for pneumatic systems can quickly tell how bad your system is and what should be done about it -- since I AM NOT AN EXPERT, DO NOT RELY ON MY STATEMENTS ABOVE.

[Michael Redman]

Have you ever watched a (US) football game and noted all the athletes that think a bit of adhesive tape applied to their nose helps them breath better?Are you talking about these? http://www.breatheright.com/exercise/exercise.asp

[krelnik]

The only difference between "Free air" and pure Nitrogen is the water vapor content.
When you are performing such that 1/4 psi of air pressure makes a significant difference, then Nitrogen is the thing to use-because it is dry.
All gasses follow the same expansion under temperature changes. The exception is vater vapor--and at 200MPH, it can make a difference. Otherwise, ots a waste of money...

Water vapor is indeed the key. There is one sensible use of nitrogen that I have encountered in street-legal automobiles, and water vapor figured prominently.

I once helped administrate a road rally in which the contestants were all driving antique cars. (And by road rally I mean what wikipedia calls a regularity rally (http://en.wikipedia.org/wiki/Regularity_rally), not what they call a road rally (http://en.wikipedia.org/wiki/Road_rally)). Antique car owners are sticklers for accuracy, which means they use tires that are authentic for the age of the car. That means many of the features that make modern tires reliable (such as reinforced sidewalls and steel belts) are not present.

Another aspect of antique car rallies is the navigators are not allowed to use computerized equipment. They have to use the stock speedometer on the car (no odometers allowed--if the car has one it is taped over!) to estimate the distance travelled over time.

The combination of these two things (ancient tire technology plus speedometers only) means these folks are absolutely paranoid about thermal expansion of their tires. Water vapor is a big component of this.

As a result, all the serious antique car rallyists fill their tires with nitrogen, to minimize thermal expansion and contraction over the course of the day, and thereby make their "regularity rally" more regular.

--Tim Farley

[SezMe]

Antique car owners are sticklers for accuracy, which means they use tires that are authentic for the age of the car.

....

As a result, all the serious antique car rallyists fill their tires with nitrogen

Seems internally inconsistent to me.

[krelnik]

Seems internally inconsistent to me.

Ha! Well, they don't wear 70-year-old underwear either.

[SezMe]

Ha! Well, they don't wear 70-year-old underwear either.
More's the pity. 70-year-old skid marks can be tough to launder. :)

[Paul C. Anagnostopoulos]

I just had two wheels broken down, rims wire brushed, and tires remounted. They filled the tires with nitrogen. I told them they could fill them with whatever they wanted, as long as they didn't charge me.

~~ Paul