Patent ID: 8141659
Filing Date: 2012-03-27
Classification: E21B

Abstract:
1. Apparatus for forming a lateral passage in earth strata beside a well, comprising: a tubular element configured to extend downwardly within an interior cavity of the well, the tubular element including an internal passage therethrough; a down hole unit connected to the tubular element so as to be supportable thereby at a predetermined depth within the interior cavity of the well, the down hole unit including a passage extending therethrough between an upper opening connecting with the internal passage through the tubular element, and a sidewardly facing lateral opening lower than the upper opening positioned and configured so as to face an interior side surface of the well when the down hole unit is positioned at the predetermined depth within the interior cavity of the well; drilling apparatus disposed in the internal passage of the tubular element and the passage through the down hole unit, the drilling apparatus being configured and operable for extending through the lateral opening for directing a pressurized fluid flow sidewardly against the earth strata or a well casing adjacent to the strata for forming the lateral passage; an abrasives addition unit connected with the drilling apparatus adjacent to the down hole unit, configured and operable for adding abrasives to the pressurized fluid flow; wherein the drilling apparatus comprises a flexible tube configured and operable for carrying the pressurized fluid flow through the down hole unit and having a lower end extendable from the lateral opening, and a nozzle carried on the lower end of the tube and configured for directing at least one stream of the pressurized fluid against the strata or the casing for forming the lateral passage therein, and wherein the abrasives addition unit comprises a container supported on the lower end of the tube and having an internal cavity containing the abrasives in connection with an internal passage through the lower end of the tube carrying the fluid flow, such that a portion of the abrasives will be added to the flow; and wherein the internal cavity of the container is connected to the internal passage of the tube by a first orifice at a first location, and a second orifice downstream of the first orifice, such that a portion of the pressurized fluid will flow from the internal passage through the first orifice into the internal cavity, and such that the portion of the flow will mix with and carry some of the abrasives from the internal cavity into the internal passage through the second orifice.