DryBox

[RON L. SHEPHERD <SHEPHRL@GWSMTP.NU.COM>]

Radsafers
We are currently looking into making modifications to some piping that is
located underwater along the wall of a Spent Fuel Pool.  One of our options
involves the use of a "DryBox".  This box has three sides and a bottom.  The
open side will be sealed to the side of the pool and the pipe to be worked will
come through a cutout in the floor which will have a pipe seal attached to it. 
The water will be pumped out of the box which will allow water pressure to
force it against the wall.  It will be supported using a crane and ballast will
be added to the box to provide a slight negative bouyancy.
We have heard that these things have been used before in the industry.  Any of
you folks out there have any experience with them?
The system that we are playing with is a Class III has anyone tried underwater
cutting and welding of piping in Spent Fuel Pools?  How did they perform NDE on
the welds?

Responses should be sent directly to me since I doubt many are interested in
this.

Thanks in advance

Ron Shepherd
SHEPHRL@GWSMTP.NU.COM