Filling Flow control question

[RedRock86]

I have a question about flow control hoping someone has some insight:

I recently picked up 5 used 3600+ storage bottles for our dive clubs compressor system. Previously we had been filling direct off the compressor and our flow control was essentially just the whip valves. The storage role as of now is just to add a buffer to reduce the compressor on/off cycling, no cascade as of now. That being said there is significant punch behind the valves and want to prevent staff from accidentally crash filling tanks if they crank the valves.

Whats the best method for added flow control to a system like this? I realise this is fairly beginner question but I am new to the fill design system. My initial plan is to add either a metering valve on the main line or a flow restrictor. But there are also flow fuses. Having a bit of trouble wrapping my head around which would be the best system if I want to have 3 or 4 whips going at once without taking forever but not crash filling, also fairly dummy proof.

Any suggestions would be appreciated.

 

[TrimixToo]

I have flow restrictors on both fill whips, one for singles and one for doubles. Pretty foolproof, which is good considering who operates it (me!). Check cascade tank pressure, open valve, and wait or walk away as appropriate. Rinse and repeat until desired fill pressure is reached. I can still exceed safe fill rates on ponies, but you can't have everything...

 

[Co. BAtguano]

what would be considered a safe fill rate (or time to re-fill) for an 80 with residual pressure of say 500 psi?

 

[Johnoly]

what would be considered a safe fill rate (or time to re-fill) for an 80 with residual pressure of say 500 psi?

NIOSH via OSHA recommends 600psi per minute air,,then do the math on whatever volume/pressure needed. Many filler's go slower than that to keep the heat down. {but I've seen an AL80 filled with 70cuft in 90 seconds-Not me>I was hiding behind a truck's tires}

 

[Co. BAtguano]

So what is the risk if you fill them too fast? I regularly fill my tanks to around 3100-3150 and then let them cool back down. Usually they're right around 3000 when they go in the water

 

[Johnoly]

So what is the risk if you fill them too fast?

The "soft parts" inside your valve will wear proportionally faster at higher and higher flow rates. What I see that wears 1st is the nylon seat. Usually if a 1000psi per minute flow push, the seat will dramatically soften up and then the filler will 'over tighten' the valve to get it to close fully without leaking. A dozen of those fast fills and you'll be rebuilding your valves. Final pressure is completely different from flow rates.

 

[BRT]

The "soft parts" inside your valve will wear proportionally faster at higher and higher flow rates. What I see that wears 1st is the nylon seat. Usually if a 1000psi per minute flow push, the seat will dramatically soften up and then the filler will 'over tighten' the valve to get it to close fully without leaking. A dozen of those fast fills and you'll be rebuilding your valves. Final pressure is completely different from flow rates.

Final pressure is very much related to fill rates because fast fill rates make for hot fills which drop more pressure when cooled.

 

[northernone]

The "soft parts" inside your valve will wear proportionally faster at higher and higher flow rates. What I see that wears 1st is the nylon seat. Usually if a 1000psi per minute flow push, the seat will dramatically soften up and then the filler will 'over tighten' the valve to get it to close fully without leaking. A dozen of those fast fills and you'll be rebuilding your valves. Final pressure is completely different from flow rates.

Logical, thank you for a practical reason. Slam fills always scared me and I couldn't justify why.

I've seen one minute fills.

Cameron

 

[1bubbleoff]

I fill at NO MORE than 300psi per minute. Keeps the heat down, saves the valve seats, ans just plain leaves me more comfortable. If I need to jam a tank....I've already screwed up by not planning ahead. JMO.

bubs

 

[RayfromTX]

My steel tanks get pretty warm even at 150 psi per minute. I am usually filling 4 tanks at a time so things get pretty cold on the supply side as I use a bank of 32%.