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3550 is going to be short. Unless those tanks are icey cold, then hey free gas!
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.
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.
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.
