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jim
 
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Default Air tank safety: Discharge rate and outlet size

adam smith wrote:

I have a couple questions about air receiver safety. I have a 20
gallon ASME carry tank (Grainger 4TK10). It has two 1/2" air outlets,
but I want to use it to honk an old fire horn which is not working
when I plumb from just one of the 1/2" outlets. I need more flow to
maintain proper blowing pressure at the horn. So my questions are
these:

1. Is there a known maximum safe discharge rate for a 20 gallon ASME
tank? The tank has a plate rating of MAWP 175 PSI @ 475 F. I need to
meter out half-second blasts at a rate of approximately 80 CFM. Is
this safe to do from a 20 gallon tank? What about from a pair of 20
gallon tanks?

2. Can I plumb the two 1/2" outlets into a common 3/4" or 1" tee? Is
there any safety reason not to?

3. Lastly, the tank has a 1-1/2" NPT inspection port that has a 1/4"
hole tapped in it for a guage. Can I replace this plug with a
1.5"-to-1" hex bushing and plumb right from there, or is this a no-no.

I want to get full flow to the horn, but I don't want to do anything
that is likely to cause the tank to lose integrity or fail
explosively/implosively. I've found lots of useful information about
maximum tank pressures, but I can't find anything on the web about
maximum discharge rates or air tank implosion.

Thanks,

Adam
adam at airraidsirens dot com

letting air out of an air tank that has pressure will not make it
implode.. the only way it will implode is if there is a vacuum inside
the tank and the pressure outside the tank is higher than the vacuum..