Bottle help

[mattz456]

Hi, I barely know a thing about air tanks but I've been playing for ages now. If someone could help me understand them a bit more I would absolutely appreciate it! At the moment I have a 3000 psi 48 cu tank and I know what ci stands for but what's cu? I'm also looking to upgrade to a 4500 psi tank or even a 5000 psi tank (got my eyes on one atm) but what does it mean by 48, 68 or 88ci exc? Also, if I was to buy a 4500 reg could I just put it on any bottle and it would work? If not why? I just want to know the basics if anyone has the time, thanks!

 

[NitroBall]

CU/CI are same meanings, CU=Cubic UNITS, CI=Cubic INCHES. These relate to the internal volume of the bottle.

It does'nt matter whether you get a 4500 or 5000 psi bottle, the max a site will fill to is 4500 psi anyway, most sites fill to only 3000 psi now.

size of bottles :
48cu = 0.8 litre
68cu = 1.1 litre
88cu = 1.5 litre

It is never good practise to have a mix of different rating of reg and bottle.
Example being : bottle rated at 3000psi, reg attatched to rated at 4500 psi.
When filling the bottle yourself, you know only to fill to 3000 psi.
If a site has air fills to 4500psi, theres a very big chance you might fill the rated 3000 psi bottle with 4500 of pressure, or a friend helping you fill your bottle, or worst you sold the bottle and reg on, the next owner is not educated enough to know that he is filling a 3000 bottle to 4.5k
3k reg has a different rated HP birst disc. These are a very important safety feature of a reg, and will break/burst letting all the air/pressure out in the event you accidently filled too much air pressure than the bottle was intented to hold.

Safety always first !

 

[mattz456]

Thanks pal, helped a lot!

 

[Tom Allen]

CU/CI are same meanings, CU=Cubic UNITS, CI=Cubic INCHES. These relate to the internal volume of the bottle.

It does'nt matter whether you get a 4500 or 5000 psi bottle, the max a site will fill to is 4500 psi anyway, most sites fill to only 3000 psi now.

size of bottles :
48cu = 0.8 litre
68cu = 1.1 litre
88cu = 1.5 litre

It is never good practise to have a mix of different rating of reg and bottle.
Example being : bottle rated at 3000psi, reg attatched to rated at 4500 psi.
When filling the bottle yourself, you know only to fill to 3000 psi.
If a site has air fills to 4500psi, theres a very big chance you might fill the rated 3000 psi bottle with 4500 of pressure, or a friend helping you fill your bottle, or worst you sold the bottle and reg on, the next owner is not educated enough to know that he is filling a 3000 bottle to 4.5k
3k reg has a different rated HP birst disc. These are a very important safety feature of a reg, and will break/burst letting all the air/pressure out in the event you accidently filled too much air pressure than the bottle was intented to hold.

Safety always first !

Yes thanks, a very good post.

 

[mattz456]

CU/CI are same meanings, CU=Cubic UNITS, CI=Cubic INCHES. These relate to the internal volume of the bottle.

It does'nt matter whether you get a 4500 or 5000 psi bottle, the max a site will fill to is 4500 psi anyway, most sites fill to only 3000 psi now.

size of bottles :
48cu = 0.8 litre
68cu = 1.1 litre
88cu = 1.5 litre

It is never good practise to have a mix of different rating of reg and bottle.
Example being : bottle rated at 3000psi, reg attatched to rated at 4500 psi.
When filling the bottle yourself, you know only to fill to 3000 psi.
If a site has air fills to 4500psi, theres a very big chance you might fill the rated 3000 psi bottle with 4500 of pressure, or a friend helping you fill your bottle, or worst you sold the bottle and reg on, the next owner is not educated enough to know that he is filling a 3000 bottle to 4.5k
3k reg has a different rated HP birst disc. These are a very important safety feature of a reg, and will break/burst letting all the air/pressure out in the event you accidently filled too much air pressure than the bottle was intented to hold.

Safety always first !

Thing is that my 48 cu 3000 psi bottle, on the curved part on the top of the bottle it says 0.74L not 0.8?

 

[Tom Allen]

Then it will be 44.4 cu/ci, but most probably marked 45cu/ci

simple maths, 48 divided by 0.8 then multiplied by 0.74.

That's assuming that 48cu/ci = 0.8L

 

[NitroBall]

If you want to get specific, its easy enough to look up on the net if Maths was not your strongest subject

45 cu = 0.737417 litres ( known commonly as a 0.7 L )
48 cu = 0.786579 litres (otherwise rounded off and commonly known as a 0.8 L )
68 cu = 1.11432 litres (rounded off known as a 1.1 L)