Nitrogen, anyone?

Cabs · 07 February 2007, 21:28

I'm friendly with some members of a local fire department that has a 19' RIB. I stopped in the other day and they were complaining about how they always have to pump their tubes up whenever they bring the RIB outside in the winter from the warm station.

One guy asked me if they could inflate the tubes with Nitrogen! At first I thought they were on crack - but then they explained that you can buy nitrogen canisters at the local autostore to inflate car tires as nitrogen is less susceptible to temperature than oxygen. After some thought, I guess it makes sense for RIBs, if there's no harm. What do you all think?

Anyone ever put Nitrogen in their tubes?

Biggles · 07 February 2007, 21:37

Kwik Fit, A UK National tyre company used to put a nitrogen mixture in tyres many years ago. Don't know if they still do. It was explained to me that it kept the moisture out of the tyres and therefore kept the pressure more steady irrelevant of the tyre temperature.

Jimbo · 07 February 2007, 22:02

Did someone else not suggest this a while back, and reach the conclusion that nitrogen was more likely to find a way of escaping through any poor seams?

Biggles · 08 February 2007, 02:09

Jimbo,

As good an idea as it might be the problem is its going to cost a bit of money to pump the average RIB up with Nitrogen for the small gain in maintanence.

I'm off to Kwik Fit soon I'll ask them how much to pump up a RIB.

But if it leaks worse than air I know one little island it won't be taking off in. Stephen L.

jyasaki · 08 February 2007, 05:22

Won't be any worse than air, and *may* have the benefit of being a bit more temp stable, and a little less oxidizing.

Remember, air is already 71 percent N2. If leakage was a problem you'd see it with air as well.

FWIW, Costco fills tires with N2 now, citing temp stability as the reason.

jky

codprawn · 08 February 2007, 12:43

Quote:

Originally Posted by jyasaki

Won't be any worse than air, and *may* have the benefit of being a bit more temp stable, and a little less oxidizing.

Remember, air is already 71 percent N2. If leakage was a problem you'd see it with air as well.

FWIW, Costco fills tires with N2 now, citing temp stability as the reason.

jky

Just going to say that - it's helium that will leak out of anything!!!

As you say air is already mainly Nitrogen so doubt it will make much difference.

Jimbo · 08 February 2007, 13:11

Quote:

Originally Posted by codprawn

Just going to say that - it's helium that will leak out of anything!!!

Ah, that was it, someone suggested helium in the tubes for less weight. I'll shut up and crawl back to whence I came now

fast fred · 08 February 2007, 13:47

Nitrogen Works. keeps my toobs from Exploadin in the Summer Sun,and from shrinkage do to cold water condesing the air in the toobs, unaffected by temp' , used in race car tires for the same reason.
if it's got a leak or a bad seam, it's guna leak or pop nomater what you put in it.

runin 7psi in the Main toobs, 12psi+ in the Speed toob, ribs, most, are 3-5psi
in the toob.

Cabs · 08 February 2007, 16:58

Sounds like it's worth a try. Can anyone think of any downsides? Now all you have to do is figure out where to get enough Nitrogen to fill the tubes... any thoughts? I guess for a fire department that's probably not a big problem.

jyasaki · 08 February 2007, 17:07

Quote:

Originally Posted by Jimbo

Ah, that was it, someone suggested helium in the tubes for less weight. I'll shut up and crawl back to whence I came now

LOL.

Yeah, helium will leak out pretty quickly through any kind of gap (or through the fabric if there is no gap.)

Besides that, there's currently a dearth of helium in the US since one of the two primary helium generation plants burned down (or something like that.) Lots of industry having a hard time getting what they need to stay in business (or were, a few weeks ago.)

jky

jyasaki · 08 February 2007, 17:13

Quote:

Originally Posted by Cabs

Sounds like it's worth a try. Can anyone think of any downsides? Now all you have to do is figure out where to get enough Nitrogen to fill the tubes... any thoughts? I guess for a fire department that's probably not a big problem.

Welding supply place should have it.

jky

Tomas · 11 February 2007, 19:00

A leak would become cause for celebration!

T

Stoo · 12 February 2007, 00:06

Quote:

Originally Posted by Cabs

Can anyone think of any downsides?

Won't the tubes get bent?

(Sorry... diving humour!)

whiteminiman · 12 February 2007, 13:39

Nitrogen is used to inflate the tyres on all Formula One cars (and many other race cars) and also the tyres on aeroplanes.

It's physically larger than the other atoms that make up air, and so leaks out far less. I'm told that oxygen leaks out three times faster than nitrogen.

If you have access to enough, then it's worth a try... although I'm not sure how much of a difference it will make considering the relatively large volumes and low pressures compared to the applications that it's usually used for.

Action Man · 12 February 2007, 19:23

Quote:

Originally Posted by Stoo

Won't the tubes get bent?

(Sorry... diving humour!)

LMFAO well done

Poly · 12 February 2007, 20:04

Quote:

Originally Posted by whiteminiman

It's physically larger than the other atoms that make up air, and so leaks out far less. I'm told that oxygen leaks out three times faster than nitrogen.

Nitrogen atoms are marginally larger than oxygen atoms (although there isn't much in it). However the air is made up from Nitrogen and oxygen molecules not atoms (plus water, co2 and traces of other stuff!). A nitrogen molecule (N2) is smaller than an oxygen molecule (O2) - largely due to the relative strength/length of N-N and O-O bonds.

If your hypothesis were true then the N2/O2 ratio of a tube/tyre filled with air would change over time. In effect if you inflated the tyre/tube until it started to go flat then topped it up - and repeated it would eventually end up with so much nitrogen that it wouldn't go flat any more - which is not the case.

The theory about water vapour seems much more logical.