Consensus on Overfilling Tanks?

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So how far off they are before you complain too much. 3300 (cold) is 96cf so you aren't being shorted enough to complain about IMO. 3100 I would complain about and ask them to top off.

How they fill is going to dictate how much they cool off. For instance even if they are filling 20 cylinders at a time - so super slow - if its direct off the compressor that gas is going to be hot. Filling 50psi per minute from a giant bank in the cold basement is going to start off colder, heat up less, and cool down less.

She filled to 3550 and I haven't checked but I'm probably at 3200-3300. I know it's not a lot, but if I wanted to say something next time I needed the right words (and you all have graciously given them to me).

That 2-300 psi is my "play at the top in 15' of water until it's really time to come out" pressure, lol.
 
She filled to 3550 and I haven't checked but I'm probably at 3200-3300. I know it's not a lot, but if I wanted to say something next time I needed the right words (and you all have graciously given them to me).

That 2-300 psi is my "play at the top in 15' of water until it's really time to come out" pressure, lol.
3550 is going to be short. Unless those tanks are icey cold, then hey free gas!
Exactly how low are you getting them?
 
I don’t agree with all this “I must have my cylinders filled to their max pressure”.

I normally dive 12Lt 232bar cylinders. It’s rare for them to be at 232, but normally over 215bar. It’s not a problem as most of my dives end with over 80bar remaining; it wouldn’t matter if I finished a dive with 50bar, so I have 30bar to play with.

For dives where I must has the gas I use 12Lt 300bar Cylinders.
 
"If you have time"...what kind of time? I was at the shop filling 2 tanks for 25 min yesterday. They didn't do it in water, but they were pretty warm when done. I can't imagine being stuck there on a summer day for longer, especially if there was a few people doing the same.

This has always been the thorn on the rose so to speak. ideal fill rate vs geting a full tank and trying to run a business. depepnding who you ask the 3 are mutually exclusive. And of course the ever cursable topic of what is an over fill.
 
Filling a tank to a pressure such that when it cools it is at the rated pressure is not bad practice, it is just not your practice.
doing that is the acceptable practice. filling a al80 to 3300 is not officially an over fill so long as when temp corrected to 70F it does not exceed 3000. So many argue that point and when I ask the question what do you do when you have a al80 tank at 3k at 70F and you take it to the lake and its warms top 95f. ,,,, Is the tank now over filled? There are some that say they are required to vent the tank down before using it.
 
Proceed as you see fit...you don't need me...argue as much as you like...

I had assumed you were better than this...

W...
where have i heard this logic of argument before. I suppose when the speed limit says 65 you dont drive 75. If so you are a rare one. Or how about no phones in school zones. and other things. The issue of whether one understands teh meaning of over fill is moot. it is a issue of why the specific psi value is there and whether it is reasonable to the user or the filler. Foire instance a LP steel barring other reasons is 2400 because that psi after 10 thousand fills will perform to certain standards in a hydro. going above that psi may result in a hydro failure after 10k fills. This topic also is a heavily beated horse. Another is O2 cleaning and the 23.5% barrier. never use to be ther euntil a decade or so ago. Oh my what would ever happen if they ever went to reason when if comes to O2 cleaning again. In addition If you know,,,,, do you know any shops the totally remove thier Nitrox piping that is exposed to greater than 23.5 and someting like 50psi from their shop for anual O2 cleaning. I or no one else I know has ever seen or heard of it being done. How about filling tanks in the compressor or cascade room. or wet filling. Wet fillng does nto jhurt a tank one bit . IT is a precaution globally pushed to insure you dont get water in the tank while connecting the fill hose. Put the fill hose on and then set the tank in a bath. No violation of the intent but is a viiolation of hte language which leavs out the intent. BTW at one time all compressed air piping was to fit under the O2 cleaning umbrella That included car tire filling equipment and auto shop air systems for hoist raising. Once the gas station cost for that was realized and it was raised the PSI to 23.5% O2. Then there is,,,,, why is it 23.5? It fits for only one form of nitrox application, but is put out as a global limit. Remember it used to be 40 % And a nitrox sticker signified only grade e hyp to be allowed in the tank because it was for nitrox of 50% or greater. Under 50% no sticker was required and you could get notrox 40 using regular grade E air.
 
If you ordered well done (ewwww) and it came out rare you would sent it back.

Why shouldn't your tank fill be any different. If its a short fill ask them to top it off.

Many shops have a policy (I have seen it on the walls) any fill greater than 2700 or 2800 is considered a full tank. A polit way of saying that they will not top off tanks after they cool. It also implies that if you dont like it go else where. Many of the same shops only fill to 3000 no matter what the temp of the tank is. they dont understand the 3000 at 70F concept.
 
Really appreciate everyone's responses. I've learned a ton and things that I didn't even think to ask that were made aware.

So the general consensus is it's ok to fill if warm to 5/4 working pressure or less so the correct pressure is in the tank when cooled off. If possible just fill slow, but that's not always possible.
Im not sure that is true I would read it as allow higher psi corrected to temp but do not exceed 5/4 working presure.

I dont know what the numbers are for todays tanks but when I started it was 5psi per degree F. if your tank when filled was 130F then it is 60F above and you can fill to 300psi over teh working pressure with out legally over fillng a tank. I dont know how the + comes into play with this. I would assusme the intent is to limit to the working presure and not the + rating psi.
 
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