outdoorellen
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Hello, About to buy a, new to me, van….it has nitrogen filled tyres…anyone have any experience of these… hints, tips and suggestions gratefully received. Cheers, Ellen
Nitrogen tyres
- Thread starter outdoorellen
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Sean
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Nitrogen has a larger molecular size than oxygen and will therefore remain inflated longer as it will not pass through rubber-based tyres.
Also reduces fire risk.
Nitrogen is produced through a membrane system, where some larger companies purchased their own systems
Users of nitrogen wheels/tyres:
Aircraft
BMW cars in Europe
Many HGV companies
Certain Fire appliances
Other safety vehicles.
Is it readily available in the UK? Cylinder bottles in the main with only a few outlets
Also reduces fire risk.
Nitrogen is produced through a membrane system, where some larger companies purchased their own systems
Users of nitrogen wheels/tyres:
Aircraft
BMW cars in Europe
Many HGV companies
Certain Fire appliances
Other safety vehicles.
Is it readily available in the UK? Cylinder bottles in the main with only a few outlets
Millie Master
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Don't quote me on it, but I believe there are several tyre fitting companies who offer nitrogen.
Norfolk NewBoy
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Always remember that air (which tends to be reasonably cheap) is 80% nitrogen.
Gordon
Gordon
mistericeman
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Pointless on most road going vehicles ...
Race cars use it to keep pressures stable despite temperature changes ...
I've used it to get me home with a slow puncture (I usually have 2 cylinders of OFN (Oxygen free nitrogen) in the back of the work van for pressure testing pipework at 42 Bar )
BUT I wouldn't pay extra to have tyres filed with it ...
Race cars use it to keep pressures stable despite temperature changes ...
I've used it to get me home with a slow puncture (I usually have 2 cylinders of OFN (Oxygen free nitrogen) in the back of the work van for pressure testing pipework at 42 Bar )
BUT I wouldn't pay extra to have tyres filed with it ...
nabsim
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When I get replacement tyres they are nitrogen filled but gradually diluted with top ups over time.
One of the coating plants (asphalt plants) we ran had a drier running on Michelin tyres, we had nitrogen cylinders at the bottom piped to the top floor so we could top up as needed. We used it because of the streamers heat on the tyres from the dryer drum, was borderline blow out temps on oxygen if I recall correctly. The tread would be molten when we were running at higher temperatures.
That not a property you would need unless in special applications though. Nitrogen holds pressure better than normal air at wide temperature ranges. So if wheels aren’t porous it can mean you very rarely need to top up tyres
One of the coating plants (asphalt plants) we ran had a drier running on Michelin tyres, we had nitrogen cylinders at the bottom piped to the top floor so we could top up as needed. We used it because of the streamers heat on the tyres from the dryer drum, was borderline blow out temps on oxygen if I recall correctly. The tread would be molten when we were running at higher temperatures.
That not a property you would need unless in special applications though. Nitrogen holds pressure better than normal air at wide temperature ranges. So if wheels aren’t porous it can mean you very rarely need to top up tyres
outdoorellen
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thanks everyone , I’d done a bit of research and felt it was probably unnecessary on a campervan under 3.5 tons…just interested really. Also I remember from school that air is 78% nitrogen anyway! so why pay to fill tyres?
They are inflated to 80psi, so apparently I need to check that the compressed air supply can fill to that level.….thanks again.
They are inflated to 80psi, so apparently I need to check that the compressed air supply can fill to that level.….thanks again.
Norfolk NewBoy
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I hate to destroy some people's theories, but ALL gases (excluding vapour components, potential phase changes and very limited effects due to molecular size and structure) will obey the Gas Laws: If you increase the Absolute (thermodynamic) temperature by 10% then pressure x volume will increase by 10%. So unless the structure (hence the volume) of the tyre changes according to the gas inside it, all gases will give similar pressure changes with temperature.
HOWEVER:
1 According to a Road & Track article, nitrogen is a much drier substance than compressed air, and doesn’t summon as much moisture as regular air when compressed into a tire. Because nitrogen-filled tires don’t have as much moisture, they’re less prone to expansion than those with only compressed air.
2 Another source states that nitrogen molecules are bigger than other air molecules and hence they move slower. So the air seeps out slower than other gas molecules making the air stay inside longer. Nitrogen seeps out 40% slower than regular air leading to a much more stable tyre
3 However, according to Tirebuyer, the average pressure loss with air was 3.5 psi; with nitrogen the average loss was 2.2 psi – a difference of only 1.3 psi over a year
www.bing.com
Unfortunately, I don't trust the science quoted in "2" because nitrogen molecules are smaller than most other components of air (Molecular masses in order of abundance: N2 = 14; O2 = 16; Ar = 40; CO2 = 28, Ne = 20 and the next most common gas is He [MM=4] which represents 0.0018%). So nitrogen moves faster than almost all other constituents.
Gordon
EDIT: Sorry N2 = 28; O2 = 32; Ar = 40; CO2 = 44; Ne = 20; He = 4
HOWEVER:
1 According to a Road & Track article, nitrogen is a much drier substance than compressed air, and doesn’t summon as much moisture as regular air when compressed into a tire. Because nitrogen-filled tires don’t have as much moisture, they’re less prone to expansion than those with only compressed air.
2 Another source states that nitrogen molecules are bigger than other air molecules and hence they move slower. So the air seeps out slower than other gas molecules making the air stay inside longer. Nitrogen seeps out 40% slower than regular air leading to a much more stable tyre
3 However, according to Tirebuyer, the average pressure loss with air was 3.5 psi; with nitrogen the average loss was 2.2 psi – a difference of only 1.3 psi over a year
Why should I Fill my tyres with nitrogen instead of compressed air? - Bing
Intelligent search from Bing makes it easier to quickly find what you’re looking for and rewards you.
Unfortunately, I don't trust the science quoted in "2" because nitrogen molecules are smaller than most other components of air (Molecular masses in order of abundance: N2 = 14; O2 = 16; Ar = 40; CO2 = 28, Ne = 20 and the next most common gas is He [MM=4] which represents 0.0018%). So nitrogen moves faster than almost all other constituents.
Gordon
EDIT: Sorry N2 = 28; O2 = 32; Ar = 40; CO2 = 44; Ne = 20; He = 4
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Millie Master
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It is a fact that all F1 teams as well as numerous other classes of racing and rallying vehicles, all use Nitrogen to inflate their tyres as it is far more stable than compressed air.
jadatis
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This " pigheaded Dutch selfdeclared tyrepressure specialist" registered to this forum to give my opinion about Nitrogen filling.
But first set some things right.
The O2 molecule is a bit smaller then the N2 molecule, because the little heavyer nuclius puls the electrons a bit closer to it.
But not only the size of molecule determines the diffusion rate of it.
What I learned is next.
If we state Nitrogen difussion rate as 1
Then Oxigen 3 times as fast
Argon 2x as fast
Carbondioxide CO2 18 times as fast
So when 100% Nitrogen in tyre, if you can manage that, so zero% Oxigen, the Oxigen from outside air difuses slowly into the tyre, wich compensates a bit the diffusion of Nitrogen to outside the tyre.
Will give text of word document I once wrote, in wich I turn it around.
Filling car tires with normal air is better then with Nitrogen.
A. Oxygen, which makes 21% of normal outside air, in volume absorbs more energy to rise a degree in temperature then Nitrogen.
Difference is only 1% , but in selling argument is sometimes mentioned in energy/ mass so Joule/kg.degr. Kelvin and there Nitrogen wins by 13 % . Tires though are filled with a certain volume so that counts .
This selling argument can be de-myth simply by the fact that its untrue.
B. Water in a tire transports the heat more then dry air or Nitrogen-filling ( which is by its production process free of water).
Not for no reason water is used in central heating and cooling system of cars as main substance.
The tire inside will have lower temperature which is better for cooling down the important spots of the tire wich have to keep a low enough temperature to prevent hardening and damage in next bending of those parts.
When incidentally the tire inside gets hotter ( sunshine on tire or severe braking, or high ambient temperature) more water goes over to gas wich highens the pressure inside the tire more then dry gas. Also then more water as gas in tire so even better cooling.
So advantage of water is 2 ways when needed, better cooling and lesser heat production.
Disadvantages of water as oxidation only happen at outside . Tire specialists will confirm that when they remove a tire of the rim , the rim inside the tire is not corroded.
C. When a Truck, transporting flammable substance, is on fire, the little oxygen in a tire will , when exploding ,probably even kill the fire .
In tunnels experiments where done to kill the fire with air current , and it worked, despite the oxygen in it.
D. A normal car tire up to truck tire is not a race-car tire, for which a constant as high as possible contact area, so best grip , is needed to give half a second better round time.
For that reason they are filled with as dry as possible air or Nitrogen.
That this gives low lifetime is not important, and for a normal car tire it is.
Often blowing tires at racing, is seen there as collateral damage, but we don’t want that for normal car tires.
E. A car tire is also not a airplane- tire in which the water can freeze and when landing this can give misbalance , which can lead to tire-failure or accident, when suddenly going from zero to about 200m/h.
The water in a car tire does not freeze that often, and when it does and the car begins do drive , it begins slow and the misbalance is not a big problem . then pretty soon, certainly when on speed the ice is melted to water and problem will be gone.
F. When filled with normal air the user is aware of checking the tires regularly, which takes better care of a saver tire, because regularly filled up to the right pressure and optical checking of the tire .
The illusion that Nitrogen filling makes the tire to loose almost no pressure, which is often exaggerated to 5 times , while in real a poor 2 times and then only in the very beginning, makes the user less caring .
The tire also looses air when hitting pavement so temporary leak between edge of tire and rim, Filling with whatever gas-combination won’t prevent that.
This idea is even stronger when TMPS is used which is often inaccurate , so the user thinks to maintain the right pressure, while really riding with to low pressure for longer time, which can lead to tire damage. Aftermarket sensors for TMPS when screwed on the valve can give leakage trough hole where valve is placed , because of the bending of the valve by centrifugal forces at speed.
G. Filling with normal air is always possible, even with a bicycle- pump, is only to fill up so won’t take that long. When you keep driving with to low pressure , in order to find a place to fill with Nitrogen, you damage your tires. So just fill up with normal outside air, even when the tire is filled with Nitrogen. Then also you don’t need to have the tire refilled with pure Nitrogen by your tire specialist when at home again, not worth the trouble, and normal air is even better then nitrogen because of the water in it.
But first set some things right.
The O2 molecule is a bit smaller then the N2 molecule, because the little heavyer nuclius puls the electrons a bit closer to it.
But not only the size of molecule determines the diffusion rate of it.
What I learned is next.
If we state Nitrogen difussion rate as 1
Then Oxigen 3 times as fast
Argon 2x as fast
Carbondioxide CO2 18 times as fast
So when 100% Nitrogen in tyre, if you can manage that, so zero% Oxigen, the Oxigen from outside air difuses slowly into the tyre, wich compensates a bit the diffusion of Nitrogen to outside the tyre.
Will give text of word document I once wrote, in wich I turn it around.
Filling car tires with normal air is better then with Nitrogen.
A. Oxygen, which makes 21% of normal outside air, in volume absorbs more energy to rise a degree in temperature then Nitrogen.
Difference is only 1% , but in selling argument is sometimes mentioned in energy/ mass so Joule/kg.degr. Kelvin and there Nitrogen wins by 13 % . Tires though are filled with a certain volume so that counts .
This selling argument can be de-myth simply by the fact that its untrue.
B. Water in a tire transports the heat more then dry air or Nitrogen-filling ( which is by its production process free of water).
Not for no reason water is used in central heating and cooling system of cars as main substance.
The tire inside will have lower temperature which is better for cooling down the important spots of the tire wich have to keep a low enough temperature to prevent hardening and damage in next bending of those parts.
When incidentally the tire inside gets hotter ( sunshine on tire or severe braking, or high ambient temperature) more water goes over to gas wich highens the pressure inside the tire more then dry gas. Also then more water as gas in tire so even better cooling.
So advantage of water is 2 ways when needed, better cooling and lesser heat production.
Disadvantages of water as oxidation only happen at outside . Tire specialists will confirm that when they remove a tire of the rim , the rim inside the tire is not corroded.
C. When a Truck, transporting flammable substance, is on fire, the little oxygen in a tire will , when exploding ,probably even kill the fire .
In tunnels experiments where done to kill the fire with air current , and it worked, despite the oxygen in it.
D. A normal car tire up to truck tire is not a race-car tire, for which a constant as high as possible contact area, so best grip , is needed to give half a second better round time.
For that reason they are filled with as dry as possible air or Nitrogen.
That this gives low lifetime is not important, and for a normal car tire it is.
Often blowing tires at racing, is seen there as collateral damage, but we don’t want that for normal car tires.
E. A car tire is also not a airplane- tire in which the water can freeze and when landing this can give misbalance , which can lead to tire-failure or accident, when suddenly going from zero to about 200m/h.
The water in a car tire does not freeze that often, and when it does and the car begins do drive , it begins slow and the misbalance is not a big problem . then pretty soon, certainly when on speed the ice is melted to water and problem will be gone.
F. When filled with normal air the user is aware of checking the tires regularly, which takes better care of a saver tire, because regularly filled up to the right pressure and optical checking of the tire .
The illusion that Nitrogen filling makes the tire to loose almost no pressure, which is often exaggerated to 5 times , while in real a poor 2 times and then only in the very beginning, makes the user less caring .
The tire also looses air when hitting pavement so temporary leak between edge of tire and rim, Filling with whatever gas-combination won’t prevent that.
This idea is even stronger when TMPS is used which is often inaccurate , so the user thinks to maintain the right pressure, while really riding with to low pressure for longer time, which can lead to tire damage. Aftermarket sensors for TMPS when screwed on the valve can give leakage trough hole where valve is placed , because of the bending of the valve by centrifugal forces at speed.
G. Filling with normal air is always possible, even with a bicycle- pump, is only to fill up so won’t take that long. When you keep driving with to low pressure , in order to find a place to fill with Nitrogen, you damage your tires. So just fill up with normal outside air, even when the tire is filled with Nitrogen. Then also you don’t need to have the tire refilled with pure Nitrogen by your tire specialist when at home again, not worth the trouble, and normal air is even better then nitrogen because of the water in it.
outdoorellen
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Extraordinary response jadatis!!!
the van with said tyres has been withdrawn from sale so no more info needed thanks….please!
the van with said tyres has been withdrawn from sale so no more info needed thanks….please!
Norfolk NewBoy
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SORRY: can't let this go so easily!
I'm not 100% certain what you are saying here but steam has a specific heat capacity of approx 2 100 Jkg-1k-1 whereas liquid water at 25degC (and possibly at 100 degC) has a SHC of 4 200 Jkg-1k-1. So the temperature of steam rises at twice the rate of liquid water for the same energy input, so it's worse at cooling IMO.
However, I'm not sure how much effect this would have, as the mass of water in a tyre is presumably not very high. Water in saturated air is 0.03kg/m3 and a tyre is probably 100 litres, so 0.1m3. Therefore mass of water is in the region of 0.003kg even if totally saturated air was used in the first place (unlikely!).
Humidity ranges from 0 grams per cubic metre in dry air to 30 grams per cubic metre when the vapor is saturated at 30 °C
Water vapor - Wikipedia
I'm open to reason!
Gordon
nabsim
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Not sure on exactly why but Michelin stated we should use Nitrogen in their tyres we had fitted to the coating plant. No idea how hot they got but it was a lot hotter than any road vehicle would reach. I know it was due to the heat but that’s all.SORRY: can't let this go so easily!
I'm not 100% certain what you are saying here but steam has a specific heat capacity of approx 2 100 Jkg-1k-1 whereas liquid water at 25degC (and possibly at 100 degC) has a SHC of 4 200 Jkg-1k-1. So the temperature of steam rises at twice the rate of liquid water for the same energy input, so it's worse at cooling IMO.
However, I'm not sure how much effect this would have, as the mass of water in a tyre is presumably not very high. Water in saturated air is 0.03kg/m3 and a tyre is probably 100 litres, so 0.1m3. Therefore mass of water is in the region of 0.003kg even if totally saturated air was used in the first place (unlikely!).
Humidity ranges from 0 grams per cubic metre in dry air to 30 grams per cubic metre when the vapor is saturated at 30 °C
Water vapor - Wikipedia
en.wikipedia.org
I'm open to reason!
Gordon
And yes the condition they were ran in was unlike any you would expect on road vehicles
jadatis
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@ post #16
I recently made a tyrepressure/temperature calculator for wet and dry gascompound in tyre.
In that I assume in a closed vessel the humidity wil always go to 100%, if enaugh water in tire.
In that I use a list of temperature and the partial pressure of water as gas at 100% humidity.
So whatever the pressure is in a tire, the partial pressure of water is for a certain temperature always the same.
Welknown is 100 degeC./ 212 degr F. Boiling point of water at sealevel.
Then partial pressure 100% humidity is 1013mb= 1.013 bar= 14.7 psi.
So if 30 psi gaugepressure so 44.7psi absolute pressure in tyre, at 100 degr C in tire, 14.7 psi is the part of the pressure made by water as gas.
Even if you put a gallon or liter liquid water in the tire. In real live its only 1 to 10 milliliter depending on filled pressure, and vollume of gas-chamber made by tyre and rimm.
That is why water boils at 100 degr C. at sealevel where outside air is average 1013 mb is 14.7 psi, the water in the kettel can keep on evaporating.
If you want to play with my spreadsheet, mail me at my hotmail.com adress with username jadatis, and I send it in return.
Combine yourselfes, spamm machines cant this way.
I recently made a tyrepressure/temperature calculator for wet and dry gascompound in tyre.
In that I assume in a closed vessel the humidity wil always go to 100%, if enaugh water in tire.
In that I use a list of temperature and the partial pressure of water as gas at 100% humidity.
So whatever the pressure is in a tire, the partial pressure of water is for a certain temperature always the same.
Welknown is 100 degeC./ 212 degr F. Boiling point of water at sealevel.
Then partial pressure 100% humidity is 1013mb= 1.013 bar= 14.7 psi.
So if 30 psi gaugepressure so 44.7psi absolute pressure in tyre, at 100 degr C in tire, 14.7 psi is the part of the pressure made by water as gas.
Even if you put a gallon or liter liquid water in the tire. In real live its only 1 to 10 milliliter depending on filled pressure, and vollume of gas-chamber made by tyre and rimm.
That is why water boils at 100 degr C. at sealevel where outside air is average 1013 mb is 14.7 psi, the water in the kettel can keep on evaporating.
If you want to play with my spreadsheet, mail me at my hotmail.com adress with username jadatis, and I send it in return.
Combine yourselfes, spamm machines cant this way.
jadatis
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Water has for every temperature a maximum partial pressure, wich they call 100% humidity.
For 20 degr C/ 68 degr F that is 0.023 bar/ 0.34 psi.
Even when 5.5 bar/ 80 psi in a tire, still 0.34 psi of it is max water.
This is easyerto understand and calculate with then somuch gramms per cubic meter.
I once found a list for that, and use it in my made tyrepressure/temperature-calculator for wet and dry.
In part 3, for giving new pressure for new temperature, and part 4 the other way around, for the wet calculation, I go from the idea that in a closed vessel the humidity will always go to 100% if enaugh water in tire.
Even made a part 5, to give for tyre completely filled to a pressure with outside air at a temperature and humidity. Then gives at what temperature in tyre all the water is gas, so above that temperature the dry calculation counts, because water is then yust another gas in the gascompound.
Playing with my spreadsheet you see that with water pressure gets a bit higher, but temperature of gascompound in tire stays a bit lower, so again a pro for normal air.
Main goal of tyrepressure determination is not to overheat the tyre-material when driving constant the speed for wich pressure is determined.
For 20 degr C/ 68 degr F that is 0.023 bar/ 0.34 psi.
Even when 5.5 bar/ 80 psi in a tire, still 0.34 psi of it is max water.
This is easyerto understand and calculate with then somuch gramms per cubic meter.
I once found a list for that, and use it in my made tyrepressure/temperature-calculator for wet and dry.
In part 3, for giving new pressure for new temperature, and part 4 the other way around, for the wet calculation, I go from the idea that in a closed vessel the humidity will always go to 100% if enaugh water in tire.
Even made a part 5, to give for tyre completely filled to a pressure with outside air at a temperature and humidity. Then gives at what temperature in tyre all the water is gas, so above that temperature the dry calculation counts, because water is then yust another gas in the gascompound.
Playing with my spreadsheet you see that with water pressure gets a bit higher, but temperature of gascompound in tire stays a bit lower, so again a pro for normal air.
Main goal of tyrepressure determination is not to overheat the tyre-material when driving constant the speed for wich pressure is determined.
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