Bluetooth Operated Tank filler Valve

[2airishuman]

whats an average fill time for a 80 cubic feet tank?

How to fill an AL80.

1. Don appropriate protective gear per your safety protocol. Eye protection at a minimum. Nothing will protect you from a cylinder rupture but you can at least protect your eyes from airborne dust, a burst hose, or a blown burst disc.
   
2. Confirm valid hydro
3. Confirm valid VIP
4. Confirm diver's certification
5. Confirm that the cylinder fill pressure is in fact 3000 PSI, because cylinders with other pressures do exist
   
6. Visually inspect exterior of tank and valve for obvious, serious problems
7. Remove dustcap if present
8. Briefly crack tank valve to blow out any water or dust that may be present in the valve
9. Connect fill hose and confirm that bleed valve is shut
   
10. Open tank valve slowly and completely
    
11. Fill cylinder at approximately 500 PSI per minute or less until 3000 PSI is reached. This is around 8 cubic feet per minute
    
12. Optionally, allow cylinder to cool
    
13. Determine cylinder temperature and use this to find a final fill pressure so that cylinder will reach 3000 PSI at 72 degrees F. Ballpark adjustment is 2% per 10 degrees F
14. Fill cylinder to final pressure
15. Close fill valve and and cylinder valve
16. Open bleed valve
17. Remove fill hose
18. Replace dust cap if appropriate

Now, situations vary, but most typically fills are from a cascade rather than a bank, though I've seen both. In a bank, the air source bottles are all at the same pressure and are maintained by the compressor at a higher pressure than the target fill pressure. In a cascade, there are several separate sets of air source bottles that operate at various pressures, and you start by filling from the lowest pressure bottle first, then use the next highest, etc. I've seen cascades with anywhere for 3 to 12 separate air sources.

Using a cascade has two benefits over a bank. A cascade can deliver more usable air before it has to be refilled, and it allows the compressor to be run at lower pressures more of the time. Banks are simpler to use and are usually used on larger compressors where a large number of cylinders get filled at once.

 

[2airishuman]

You are not filling an 80, you are filling a pony. No? Anyway, 10 minutes is a nice fill time. 20 is boring, 5 is hot.

He's trying to build a vending machine that sells air fills. I don't know if that's a good idea or not. ::shrug::

 

[Rred]

Not to be cruel but bluntly?

This is like trying to flush a toilet by remote control. Usually a pointless exercise, considering all the other parts of the operation that require trained human intervention and action.

As a diver, would you buy air from....some random street vendor, with no certifications or assurances attached to it?

 

[tursiops]

He's trying to build a vending machine that sells air fills. I don't know if that's a good idea or not. ::shrug::

I'd rather go to Amigos and do my own fills. Wish I lived closer!

 

[tursiops]

He's trying to build a vending machine that sells air fills. I don't know if that's a good idea or not. ::shrug::

How do you know this?

 

[Johnoly]

.. I don't know if that's a good idea or not.

I've filled ALOT of tanks. Lots of stuff goes wrong at 3000psi and can kill you. You have to be watching everything with your own eyes and know what to do quickly when stuff goes wrong. An electronic valve is nice, but I've seen an AL80 blast right thru an 8 inch concrete wall and keep going. No insurance company in the world will write a policy on the setup and the fire marshal will be all over it too.

 

[2airishuman]

How do you know this?

I see lots of similar ideas in my day job.

Maybe I'm wrong. Let's call it a rebuttable presumption.

 

[2airishuman]

I wonder if the OP's garage is still there.

 

[pay]

Yes I've successfully filled tanks, now working on regulating the flow to the tank for cooler fills this would be in a dive shop just fyi.

 

[pay]

You are not filling an 80, you are filling a pony. No? Anyway, 10 minutes is a nice fill time. 20 is boring, 5 is hot.

The pony was for testing purposes the goal would be an 80 cubic feet tank.