| Author | Message | ||
     Bob UK Unregistered guest Posted From: 94.197.122.82 |
This is the in thing for cars. Evidently because nitrogen moles are bigger than air the tyres lose less pressure over time. If that is true then because air is 79% nitrogen, it must mean that the oxygen leaks out only therefore leaving a higher nitrogen mixture level. And when pumping air in eventually after a few months of pressure checks and top ups, the tyre will be mainly nitrogen. I have never noticed tyres failing because they had air in them. (Message approved by david_gore) | ||
| Jan Forrest Grand Master Username: got_one Post Number: 752 Registered: 1-2008 |
The use of nitrogen isn't as new as you think, Bob. I was a tyre fitter back in the 70's and for call out use our trucks (except one) carried nitrogen cylinders to reinflate tyres at the roadside. The theory is that the oxygen (all 20% of it) will make the interior of the tyre perish faster. My experience is that the outside perishes way faster due to UV exposure! Truck inner tubes might last longer, but I doubt it would be a significant factor. | ||
| Bob UK Unregistered guest Posted From: 94.197.122.89 |
I think that nitrogen to inflate tyres at the road side as a matter of convenient supply of pressure. Dunlop say that nitrogen is best for aeroplanes because of ice. But see no advantage for car tyres. The fans of nitrogen say that as the tyre warms the pressure stays the same. And that if air is used the rise in pressure could burst the tyre and that for a small sum of money you can guard against your family being injured. Thermodynamics says otherwise. Hotter nitrogen expands, PVT and all that jazz. A tyre that is recommended to run at 30psi Will go well over a 100 psi before it bursts. So going from 30 to say 40psi when hot is not going to burst the tyre. Regardless of the gas used the outside of the tyre is in air. Also no mention in the blurb that air is 78% nitrogen. I have seen inside many old tyres and they look like new inside. I reckon it's more UV than oxygen that does the damage. (Message approved by david_gore) | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 922 Registered: 9-2004 |
"But see no advantage for car tyres." Try a track day at Goodwood etc with out nitrogen in the tyres, result in the lead for a few laps then the tyres let go as the pressure rises slower lap times occur if your still mobile!!!!!!! | ||
| Randy Roberson Grand Master Username: wascator Post Number: 352 Registered: 5-2009 |
Maybe; at Fellowship if we make it around the corner at the cemetery we are home free. Nitrogen is conveniently available in high-pressure cylinders; handy for replenishing tires. For aircraft, the added bonus is that in case of tire or brake fire, the tire contains nitrogen which will not support and can help supress fire, rather than air with oxygen. Also the tires are subject to extreme temperature swings and need to be reliably perfect for every takeoff and landing cycle. nitrogen for average motorists' tires is in the same category as paint sealant imo. To each his own. | ||
| Bob UK Unregistered guest Posted From: 94.197.122.85 |
Dunlop say that the difference in pressure is very small. Also what if the atmospheric pressure changes. Also even at zero gauge pressure there is still air in the tire. Unless a vacuum is applied which will suck a tubeless tire off the bead. If a tire at zero is inflated to 30 psi with nitrogen then the tyre will contain one third air which contains 20% oxygen. So the mix will be 1 part oxygen to 15 parts nitrogen. Sort of weak air. (Message approved by david_gore) | ||
| Vladimir Ivanovich Kirillov Frequent User Username: soviet Post Number: 87 Registered: 2-2013 |
I say it does not matter except the pressure. I have had a lot of experience punishing tyres and a lot of perhaps, divine intervention. I inflate the tyres of my 1990 severely cow and kangaroo struck Falcon Panel Van loaded with one ton of hand tools when I venture the length and breath of Queensland Australia looking for unsuspecting employers who will pay me if I pretend to work. I travel on roads to and back from hell. I inflate my tyres to the maximum of 55 psi. I hardly ever get a flat. Now the Mad Scot whom which I dwell has the other experience. He, in his flash Kia Serento is a mechanic like me but who in his great Kilt like wisdom likes to run the enormous tyres on the Kia at low pressures. We have on more one occasion got about 40k from the front gate when he pronounces something is wrong, he thinks its another %#@*ing tyre. The Scot is not someone to tangle with at the best of times and when he stops the car and sees another disintergration he flies into a Scot type rage and attacks the nearest gum tree, and sometimes gnaws at its trunk while foaming at the mouth. Most nasty. But the bugger won't inflate his tyres to maximum so I diplomatically keep my distance and laugh hysterically while he changes yet another tyre. I don't like tyres and I put them them into the same category as politicans world wide and batteries (also a suspect species). It think the key is inflation not the gas if you are talking real brutal environmental type drives. | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 614 Registered: 5-2012 |
Vladimir All is now explained. I wondered how a Russian who has never lived in England knew of so many English references, words and phrases. All care of your friend the Scot. Mystery solved. Geoff | ||
| Vladimir Ivanovich Kirillov Frequent User Username: soviet Post Number: 88 Registered: 2-2013 |
Perhaps that is not true, Geoff, there are things about Scots like the fact they have women who have lots of freckles and long wavy red hair, they have bagpipes and they make insane friendships with people like like me for I Geoff SOVIET, I have to tell you ugly truth, more in common with west than you can imagine. My brother Sasha, is in love with Margret Thatcher, his is Russian and is not amused when we have to pay Russian Police Force Militzia to be delivered home after I have got out of control. Geoff google Russian Rocket Fast. Scroll to world's most fast nuclear rocket. I love it, I see the light, just like when Slade played London. The differences between CCCP and USA culture are much slimmer than is announced. Sasha said to me one day only one Rolls Royce in Samara Russian Federation. A few days later we were looking at Chaika owned by top Soviet General price $5000. Geoff be a good lad and check out prices for a Zil.Its a lunancy. All money in CCCP ended up in military hands because of Churchills yap at American university. Stalin blew his top but in the end we are not that different. | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 615 Registered: 5-2012 |
Vladimir I absolutely agree, the differences between us are not great and I was not in any way alluding to that in my email. I was just curious about your exposure to UK English as opposed to American and Australian English. One of the great things about this forum is it is international and political differences mean nothing. Geoff. |
