Patent ID: 7690428

Claim:
A method of perforating a downhole pipe in proximity to a closure in the pipe, the pipe having a longitudinal axis, comprising: a) positioning a cutter in the pipe in proximity to the closure; b) using the cutter, producing cutting fluids in a first radial direction toward the pipe, wherein the production of cutting fluids produces a reaction force and a pressure wave in the pipe that is reflected off of the closure and back to the cutter; c) using the reaction force to move the cutter against the pipe, wherein the cutter is temporarily anchored to the pipe when the reflected pressure wave impinges on the cutter; d) while the cutter is anchored against the pipe by the reaction force, continuing to produce cutting fluids in the first radial direction and creating an opening in the pipe; e) positioning a radial cutter in the pipe in proximity to the closure, with the opening located between the radial cutter and the closure; and f) operating the cutter to radially cut the pipe.