On Tue, 29 Nov 2005 13:22:30 -0800, Grant Erwin
wrote:

Ignoramus20878 wrote:

Is that 20 cubic feet per MINUTE or per HOUR?

Ah. I think I'm beginning to see where I was led astray. If it's CFH, and the
tank is rated in cubic feet then the math is trivial. Thanks.

GWE

Its indeed in CFM/H

Gunner, who pays $18USD + $3 for a 135 CF tank of Argon OR C25


I think that a simple division would suggest that at 20 cfH, it would
last for 125/20 hours, or approximately 6 hours (note that also some
gas will be left in the tank). You divide the fill cost by 6 (hours)
and then by 60 (min/hr) to get the cost per minute.

Say your fill cost is $48.

Cost per minute = 48/(125/20)/60 = 12.8 cents per minute or $7.68 per hour.

i

Is there a primer somewhere online or in a book that breaks this down?

Grant Erwin




"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner