Bank size help...

[jrmiah]

If I want to fill 30 * LP 85 steel tanks (2400-2600 psi) a day max, how would you set up your cascading bank system, how many 444/4500 psi storage tanks would you need?

I was thinking about a three line cascading system.. Thoughts?

Thanks in advance.

 

[nadwidny]

If I want to fill 30 * LP 85 steel tanks (2400-2600 psi) a day max, how would you set up your cascading bank system, how many 444/4500 psi storage tanks would you need?

I was thinking about a three line cascading system.. Thoughts?

Thanks in advance.

To start with I wouldn't go with all 4500 psi cylinders. I would have a bank of LP (2400)cylinders at the beginning because (a)they are much cheaper than the 4500's and (b)the top end of the 4500's goes so quickly when filling into empty or near empty tanks that the wear and tear on the compressor to get them up to the pressure isn't worth it.

There was a great article written by Ted Green on Decostop about setting up a cascade system but I can't seem to find it.

Edit - Found it - The Deco Stop . Ted is O.C. Diver. Posts 11 and 14 have some very good info.

 

[jrmiah]

So your saying that you can fill 30+ tanks a day to 2400-2600 psi from 2400 psi banks?

 

[cmalinowski]

So your saying that you can fill 30+ tanks a day to 2400-2600 psi from 2400 psi banks?

Cascading you will. And he didn't say all bank bottles should be 2400psi. But all don't have to be 4500 either. If you have unlimited funds, go for all 4500's.

Chris

 

[jrmiah]

Cool, thanks for the clarification. So perhaps 2 bank lines of 2400 and then a "top off" line of 4500. How many of each do you project you would need to fill 30 tanks a day?

The background is basically for a 6 pack operation running two (2 tank) trips a day. All the tanks would be filled at the end of the day instead of between the two trips.

Thanks in advanced.

 

[barc802]

If you have 6 4500 storage tanks on cascade you should be able to fill 27 80/3000 psi I could not find a chart for low pressure tanks. Here is the link reliable0air.com - Cascade Systems

I have a 4 4500 in 3 banks, my first bank has 2 cylinders and the other 2 banks each have 1 cylinder. I can fill about 20 tanks to 3000 but it really depends how empty they are.

 

[cool_hardware52]

If I want to fill 30 * LP 85 steel tanks (2400-2600 psi) a day max, how would you set up your cascading bank system, how many 444/4500 psi storage tanks would you need?

I was thinking about a three line cascading system.. Thoughts?

Thanks in advance.

There is no "one answer" to this question. Lots of variables. I assume that the bank bottles will be at the compressor location, so you also have the output of the compressor to supplement the gas in the bank.

What capacity compressor do you have?

How fast do you need to fill the 30 LP 85's? As quickly as possible, or over a couple hours?

How fast do you need to refill the bank? At worst case (all the 85's are empty, not too likely, but worst case) you need 2550 cuft of gas at 2640. With a 5 cfm pump you will need 8-9 hours to replenish the bank. Do you have somebody to run the compressor and switch banks as they fill?

There are valves that will switch banks automatically, but they add complexity and aren't free. Look here http://www.aquaenvironment.com/om/1024_OM_1018_031024R.pdf

You may find that more scuba tanks will allow you to manage with a fairly small compressor and modest bank, as the extra tanks (more than the 30 you need daily) will act as the "bank" as long as you have somebody to fill them during the time the "other 30" are in service.

Good luck,

Tobin

 

[jrmiah]

Thanks all for the input.