Air tank capacity

Not too sure yet? I havent made my compressor but a mid range 12 volt compressor would probably pump it up to about 140psi at a guess.

Im trying to work out how much pressure I would have to put in the cylinder to pump up 4 tyres and if the cylinder could hold it.
Some of the details on the cylider lead me to think it can hold 200 or 300 bar
200 bar = 2 900.754 760 144 pound/square inch.
Does that sound right???
Suppose Id have to work out the volume of the tyre and psi needed and divide it up????

I can see where you're coming from Hairy, but the physical size of the tank will have more affect on it's ability to pump up tyres than what pressure it can handle IMHO. Unless you're taliking about the ridiculously high pressures used in those "Air-Up" set-ups or the likes of a diver's scuba tank etc. Those units do rely on very high pressures, but the tanks are constructed like.....well.....Tanks (as in army tanks!!!! hahaha)

If I'm correct in my assumption that your tank is about the size of a shoe box (say 5" diameter and 12" long), then even if it is capable of handling 200psi, you're still not gunna be able to re-inflate one tyre, let alone 4.

Cheers

Roachie

Roachie, 200 Bar = 2900 psi

Cheers mate.......I didn't know what the conversion was........now all he's gotta do is buy the mutha of all compressors to get the tank to that sort of pressure and he'll be able to do as many tyres as he likes ;-)))

Oldplodder you shouldnt confuse the issue with citing atmospheric pressure unless you want to talk about PSIA as to the difference of PSIG

even if the tyre is flat it is at atmospheric pressure... and thats 14.5psia approx or zero psig

PSIA is pounds per square inch absolute where-as psig is pounds per square inch gauge.

just using your figures of psig is suaitable..ie your calcs have nothing to do with atmospheric pressure unless we compare a tyre here on earth to one on a LRV...(Lunar Roving Vehicle) on the moon..the moon is a almost perfect vacuum or 0 psia.....get the idea...

no offence meant matey

Thanks numero uno.

Hard to keep it simple and still get the idea across that you can fit more air in than the actual atmospheric volume :-)
Always found it confusing gauge and absolute, been too many places where I have seen both used.
But a point worth raising.

you didnt forget to add in the 40psig that you cant get out of the cylinder after inflating the tyres did you?...ie you cant get that last little but out out once the tyre pressures match the cylinder pressure..

So legend! Why dont you just tell some of us dumb a r s e s the answer instead of just saying were all wrong.

as i dont have a use for it, there is no need for me to know, so what can I tell ya

Not so clever after all hey!

assumption: Cylinder pressure 100 psig

from my experince of working with gases and volumes of pipework and pressure storage vessels the peesy little 2.8l cylinder will not pump the tyre to 10 psig let alone to 40 psig.

Forgetting about expansion rates etc, Its all a matter of volume and with out all the Correct volumes one cant work it out...the figures bandied about above are at best a guess of a tyre volume

also,
no and never said I was smart
but it does appear i might have a lot more knowledge on the subject than you so it would be appreciated if you'd accept the title of "dumb a r s e"

Yep... I can tell that. All the intelligent info you have passed on has been fantastic!
Just one thing still doesn't make sense to me (As a Dumb A R S E) .... From your advice, and Ill put it in another scenario, your saying its all volume. So... If iI got an empty cylinder( atmospheric pressure of 14psi as you have called it) and put a balloon over the end and opened the valve it would do the same as it would to the same size cylinder with 2000psi in it? mmm I like you knowledge!!!
I think I might go with everyone else's helpful but not as knowledgeable advice.
Cheers

another jerk...bloody hell

cant you read?

if you had an empty cylinder of 14.5psia, which is atmospheric pressure it wont inflate a deflated balooon...cos they'll both be at the same pressure!

read what was said Hairy....try to understand that 14 psia is atmospheric pressure or in other words zero psig....psia and psig are not the same readings when shown on a gauge...theres is a difference of 14.5 psi....look no a or g after psi
if your still confused let me know

"So... If iI got an empty cylinder( atmospheric pressure of 14psi as you have called it) and put a balloon over the end and opened the valve it would do the same as it would to the same size cylinder with 2000psi in it?"...i said nothing of the sort....it certainly is another scenario..one i have no idea of what your trying to say.....

If it is an empty cylinder, and you put a balloon over the end, wouldn't the balloon get pushed inot the cylinder?
Empty cynlinder to me means no gas or anything in there, so air pressure would push the balloon into the cylinder?

I know splitting hairs, or atoms in this case, since you can not have an empty cylinder at 14.5psia :o)

See, i am learning quick from numero uno. Don't argue the facts, stir instead, it is more fun :o.

yep if the cylinder has nothing...not even air, then then yes oldplodder

it would be zero psia eh...or approximate 28 inches of vacuum.....now dont start on this oldPlodder...just forget i said anything about inches of vacuum.......hahaha

No. 1,
Im starting to think a few of my simple questions must of put you on some sort of pedestal ,I realy was looking at some sort of advice from a variety of people with different backgrounds and different trade areas. Apparently Ive seemed to have crossed some sort of line with you.
Being called a jerk when im actually looking for sound advice doesnt sit very well with me so Ill leave this forum with a few ideas I have from the decent people who commented. I cant understand why a simple question has to be so hard.
Remember the question???
(These are the stamped details on a bottle I have that I want to use for a compressor tank.
2.7mm 4.83kg 2.8L
P 200 PH 300 Bar
Does anyone know the calculation I need to do to work out how many tyres I can pump up with this)

If there wasnt enough info or you or think its not possible say so but dont try to get personal and critical about others comments!
If you ever happen to come through Alice, need somewhere to do an oil change, borrow a shed, or generally need someone to pull you out of the s h i T give me a call, Id love to meet ya!

but you gave us no info Hairy...only the fact you had a 2.8litre cylinder
Tell me the tyre and wheel volume and I will tell you what you what to know

I do question the 300 bar bit...no idea what the 200 is though

and thanks for the offer

ps I thought had deleted that jerk bit...but thats life

Cheers Mate, thanks all

not all dive tanks are 4000 psig..most are well below that, especially the alloy tanks