Scalding hot tanks

[String]

. Like a hand grenade the shrapnel would be less likely to kill you.

Except tanks don't fail in that way plus the most likely bit to go is going to be the neck thread or valve which would have no protection anyway.

 

[spectrum]

On the contrary, my 4 stage portable is a bundle of all finned intercoolers and the air entering the coalescer between third and fourth stage (also carries the bulk of the condensate) and the final coalescer after the fourth stage are at ambient temperature. The final coalescer has a very faint mist on blow down and the filter tower is also near ambient.

Cool! (no pun intended)

You have a leg up on the shops I have been in.

Pete

 

[Peter_C]

I had the valve off this tank to vis it, so starting pressure was zero psi. Started filling from my very low banks (3,400psi was the top bank), then ran the compressor to top it up to over 4,000psi so it would cool to a solid fill that wound up at 3,800psi. There were two more HP130's connected to the compressor for top off at the same time. Warm once filled, yeah. Hot? Not every close. This was shot a minute or two after the fill was completed, so the temp was not still climbing. Slow filling is not a bad thing...

 

[Basking Ridge Diver]

Except tanks don't fail in that way plus the most likely bit to go is going to be the neck thread or valve which would have no protection anyway.

Safety alert - Safe filling of portable aluminium alloy cylinders - Workplace Health and Safety Queensland

However - most likely is closer to always than never -

 

[Michael Guerrero]

It's not a big deal. If I'm getting a hot fill I usually ask them to over fill a few hundred PSI, and when they cool they come down to the right pressure. Sometimes you're in a hurry

 

[mainer04270]

I have been diving for a LONG time, and I have seen tanks filled at every resort I've been to. I have never seen tanks filled while in cold water. I have never even heard of this, before, and I have been all over the world, diving. Interesting, though.

 

[jwj500]

You're not going to be happy if the tanks are at the correct PSI after they cool? You should probably take a deep breath, relax, and realize that you aren't using 100% of that air anyway. Standard AL80 tanks are supposed to be filled to 3000psi. IF you get a little more, be happy. If you get a little less, it's no big deal.

:cool2:

 

[imjustdave]

Anyone know how commercial air and gas supply places fill tanks? You know the full tanks used in comercail applications like helium, Argon, Co2, Hydrogen, 02, etc. How do these places fill their 100's of tanks?

David

 

[theduckguru]

Amigos Dive Center. Ft White Florida.
Note the water bath.


Sent from my iPhone using Tapatalk

Note they are filling tanks out in the sun and in the back of a hot van too

 

[FlIrishman]

So I waited today while the dive shop filled my tanks. I was driven there by a friend, who commented he had not seen tanks filled before out of the water. I said, wow, these are hot. Another diver had just walked out of the store after his first visit, and commented there was no way they filled them without being in the water. He then felt the tank, and said, yup, filled out of the water. He said he would not have his tanks filled here.

Being newer to this sport/occupation I was unsure, as I had never waited before for my tanks while being filled. Is it normal to give them back very very hot? Is it normal to fill them without cooling in water?

The Math you can use to determine the room temperature pressure of a Hot Filled dive tank
From: George W.J. Kenney, Jr, Professor of Chemistry (Retired), MS Organic Chemistry

P (final) = P (initial) * T2 / T1

Pressure can be in any units, so use PSI

T = Temperature in Degrees K = (Degrees C + 273). Remember 0 C = 32 F = freezing of water, 100C = 212 F = BP of water

So assume the final temp of the hot tank is 80 C and the desired room temp is 25 C (on a hot day)

P (final) = P (initial) * T2 / T1 = 3000 PSI * (25 + 273) / (80 + 273) = 3000 PSI * 298 k / 353 k = 2533 PSI

If you paid $10 for the fill, you really got only 2533 * $10 / 3000 = $8.44 worth of air!!

So that hot fill to 3000 PSI will go down to 2533 PSI when it cools off - YOU GOT RIPPED OFF!!!

I would NEVER USE A HOT FILL DIVE OPERATION!!

Taken from my College Level Chemistry I Lecture Notes!