Patent ID: 6892832

Claim:
Apparatus for earth boring comprising a tool for attachment to a drill string, comprising: a tool body having a longitudinal axis and including a makeup end; a threaded pin extending from and integral with the makeup end of the tool body; a radially-extending surface at the makeup end of the tool body, the surface extending outward from the threaded pin to an outer surface of the tool body, the radially-extending surface having an angle of less than 15 degrees with respect to a plane perpendicular to the longitudinal axis; a breakable washer positioned on the radially-extending surface of the tool body, the breakable washer having a radially-extending first surface substantially perpendicular to the longitudinal axis of the tool body and a radially-extending second surface having an angle of less than 15 degrees with respect to a plane perpendicular to the longitudinal axis; and the second surface of the breakable washer being disposed at an angle greater than zero with respect to the first surface of the breakable washer, such that the first and second surface of the breakable washer are not parallel to each other, and a cross-section of the breakable washer is radially diverging.