Warning about hot fills!

[drbill]

As has been pointed out, a leaking valve is a far more probable cause. My tanks rarely "lose" more than 200-300 psi after a hot fill. None of the shops here immerse tanks in water when they fill them.

However, with that said, I did have one of my PST HP120s fail hydro due to over-expansion. Even the dive shop manager where it was filled the most believed it was due to repeated hot fills. I don't worry about a "hot" fill if my tank is being filled along with a number of other tanks. However, I do worry about them if mine is the only tank being filled.

 

[Doc Harry]

I would solve this problem by requiring that this particular customer will need to be charged for a visual inspection before each and every fill.

 

[yodelhawk]

please don't think I'm trying to hijack this thread....please just a quick answer, what is a Q & A?

 

[gcarter]

please don't think I'm trying to hijack this thread....please just a quick answer, what is a Q & A?

Question

&

Answer

 

[ti325v]

Quality Assurance..
The bigger the shop and the more certs they issue, the less it matters.
I have seen a course director certify customers that could not pass a swim test, I have been asked to teach courses that I was not qualified to teach (Not a specialty instructor at the time) course completed, papers went to other instructors for sign off...

Went the Q.A. route...nothing happens..

 

[NAM001]

50 is for o2 and i think 600 is max per psi

50 PSI/min is the recommended filling rate according to CGA (and maybe that's O2 and not air, but I think it's air). Now, go to a gas house and see when they have 75 or 100 O2 or air cylinders on the fill rack, it's easy to maintain 50 PSI/min. It's a little more difficult in a dive shop with 2 fill stations or on a liveaboard with 6.

 

[scadreau]

I know paintball is a little different that scuba but...

I paintball a lot. We use 4500PSI 68 cubic inch tanks. During the course of a tournament or practice, I may fill my tank from ~800 to 4500psi 50 times in a day. This fill process is usually done in less than 15 seconds. If I do a fill at the end of the day and bring it home, it may lose a couple hundred psi. Some fields have such dirty compressors that I have sand in several of my tanks. In the Arizona sun, it is often unpleasant to touch the valve after a fill. Multiply this by the hundreds of tanks that my friends and I are using and we have a fair sample size. None of us have ever ended up with a failed hydro.

Given this experience, I have no issue filling my scuba tanks at 600psi/minute.

 

[Tigerman]

The good thing about scubadiving and paintballing is that you get fill adapters for scubatanks to fill your paintball tanks