In einer eMail vom 12.04.2002 18:55:14 (MEZ) - Mitteleurop. Sommerze
schreibt heinzind@cadvision.com:
Here is my 2 cents worth..
I tested my sub to 10 feet in a small pond, mostly to
check for leaks, and to make sure everything worked right.. I then got some
advise from 2 experienced subbers, and they both suggested to do the unmanned
deep water test.. I thought it over, and decided that I had too much money and
time tied up, to just leave the sub there, if there was a problem.. again, the
problem could be as simple as a leak, not a total collapse.. I
contacted a local company that pressure treats lumber, and after some talking,
they decided they could help me out. I tested my sub in their pressure
chamber, after being convinced that a failure of my sub, would not damage any
of their equipment..for me this was the best way to go, but the longest few
hours of my life wondering if all my hard work would pay off.. The only
problems I encountered was the pressure went up very fast, and came off even
faster.. 0-400 feet in 15 seconds, 400 - 0 feet in 0.5 seconds..
dale
Hi Dale,
So your sub is secured
against rot for all the time ??? :-))
Itīs a good idea to
look for unusual test chambers... offen there is a lot of pressure around us
but we didnīt note this... :-))
Was 400 feet the
maximum capability of the chamber or was it your choise?
A.
yes 400 feet was the max capacity of this
chamber. It was also the max depth I have my pressure compensation set at for
my motors. The chamber itself was 83
feet long, and 6 feet in diameter.. It would hold a
lot more pressure, but they overbuild them because they are being cycled many
many times. The place I used treated lumber at 145-170 psi, depending on what
chemical they were using.. and you are right.. even though they cleaned out the chamber for me, and tried
to clean out the pipes, there was still some chemical in the water. It washed off, and does not seem to harm
anything. (it left kind of a waxy film on
everything..) The
chamber is pulled to a vacuum, then filled with liquid (water mixed with
whatever chemical) the
vacuum allows the pumps to prime, and the chamber to fill completely. I could see the high water mark in the
chamber, and it was very close to the top at the door..(the chamber slopes down slightly at the rear to aid in
emptying.. ) Liquid does not compress
for our purposes, so adding pressure or releasing pressure can happen very
fast, and does, because they don’t care how fast they do it for lumber..
I took some pictures, I’ll see if I can get them scanned,
and send them to Ray, to post..