Drill bits with bearing elements for reducing exposure of cutters

摘要

A bearing element for a rotary, earth boring drag bit effectively reduces an exposure of at least one adjacent cutting element by a readily predictable amount, as well as a depth-of-cut (DOC) of the cutter. The bearing element has a substantially uniform thickness across substantially an entire area thereof. The bearing element also limits the amount of unit force applied to a formation so that the formation does not fail. The bearing element may prevent damage to cutters associated therewith, as well as possibly limit problems associated with bit balling, motor stalling and related drilling difficulties. Bits including the bearing elements, molds for forming the bearing elements and portions of bodies of bits that carry the bearing elements, methods for designing and fabricating the bearing elements and bits including the same, and methods for drilling subterranean formations are also disclosed.

主权项

1. A rotary earth boring drag bit, comprising:
a body including blades and a crown comprising a cone at an axially leading end of the body; cutters mounted to at least one blade; and at least one bearing element positioned on the at least one blade and protruding from an axially leading surface thereof, defining a bearing surface located at least partially within the cone for disposition against an earth formation during drilling and adjacent one or more cutters on the at least one blade, the at least one bearing element located rotationally behind at least a rotationally leading portion of each of the one or more adjacent cutters and including a quantity of material protruding above an axially leading portion of the at least one blade extending laterally to at least one side of at least one cutter of the one or more adjacent cutters and abutting the at least one cutter along a rotationally trailing end and along at least a portion of one side of the at least one cutter, the at least one bearing element being configured to effectively reduce an exposure of the one or more adjacent cutters, wherein the at least one bearing element extends laterally along the at least one blade a distance greater than a greatest lateral width of the at least one cutter.