Patent ID: 8833451
Filing Date: 2014-09-16
Classification: E21B

Abstract:
1. A system for opening a window in a casing string during lateral wellbore construction, the system comprising: a window joint operable to be interconnected within the casing string, the window joint having a preformed window formed therein defined by at least one score line that creates a preferentially weakened region within the window joint enabling internal removal of the preformed window in a predictable manner, the at least one score line having at least one section extending circumferentially about a portion of the window joint and at least one section extending longitudinally about a portion of the window joint, the preformed window having a generally radially extending tab disposed on an interior surface thereof, the tab having a first surface and a second surface that is oppositely disposed from the first surface and that is defined by at least a portion of the at least one score line; and a window removal tool operable to be run in the casing string and operably engagable with the first surface of the tab such that actuation of the window removal tool removes the preformed window as a single piece from the window joint to an interior of the casing string, thereby opening the window, and wherein, retrieval of the window removal tool to a surface of the wellbore retrieves the preformed window as the single piece to the surface of the wellbore through the interior of the casing string.