A platform is used to deliver a tool down a hole by controlling the flow of fluid
through and around the platform. The platform has a top surface for receiving the
tool. The platform also has a bottom surface to provide guidance through and resistance
to the flow of fluid. The lower surface of the platform can be engineered to steer
the platform against an inner wall of the casing. This slows the descent by adding
mechanical friction to its descent. The lower surface can also be engineered to
add a predetermined amount of resistance to the flow of the well fluid across it.
A stop on the casing already in place in the well stops the descent of the tool
at a desired depth. Once the tool is no longer needed, a fishing tool can be lowered
from the same crane to retrieve the tool and platform. Use of a crane substantially
decreases the cost of the operation compared to the need for a rig.
