Patent ID: 8146672
Filing Date: 2012-04-03
Classification: E21B

Abstract:
1. A method of installing a drilling tool at a lower end of a string of casing suspended in a borehole, comprising: (a) providing a drill lock assembly with a housing, a plurality of axial lock members carried in windows in the housing, a cam member carried within the housing for selective axial movement and having a lower tapered portion and an upper end located below an upper end of the housing; (b) attaching a drilling tool to the drill lock assembly and the drill lock assembly to a running tool, the running tool having a latch mandrel that extends into the housing of the drill lock assembly and abuts an upward-facing surface of the cam member, and lowering and landing the drill lock assembly into a profile sub in the string of casing; (c) applying a downward force to the latch mandrel of the running tool to cause the latch mandrel to move the earn member downward relative to the housing of the drill lock assembly, the tapered portion of the cam member pushing the axial lock members outward from a retracted position to an engaged position in engagement with the profile sub; then (d) releasing the running tool from the drill lock assembly and retrieving the running tool along with the latch mandrel.