|
NP- You are right, the psi is the same. The mechanical advantage does apply
with a decrease in volume though.
The analogy of a square, one inch rod, pushing into the sub's one
atmosphere gives you a certain pressure, where as a 1/4 inch round rod ( or hose
) would push less.
Still, to push something out of the sub ( like ballast water) will require
a pump able to push the 267 psi.
Depending on the volume pumped, 267 psi is easy to achieve, and in
the case of a trim tank, you're pumping air into a tank to expel the
water.
I've got a small compressor in my vehicle for emergency roadside repairs
that pumps to 250 psi ( but at a very small volume ) that runs on 12
volts.
The pressure in a scuba tank is much greater than what we'll get in our
trim tanks.
Blowing out the trim ballast ( adjusting trim en route ) must be part of
the system or we'll have to surface constantly to dump the water.
Frank D.
|