Cutting structure for roller cone drill bits

Abstract

Cutting structures for roller cone drill bits are disclosed. One aspect is a drill bit which includes a bit body, and a plurality of roller cones attached to the bit body and able to rotate with respect to the bit body. The bit further includes a plurality of cutting elements arranged on each of the roller cones so that cutting elements on adjacent cones intermesh between the adjacent cones. The cutting elements are arranged so that a rotation speed of each cone differs by less than about 7% from the rotation speed of each of the other cones during drilling. Another aspect is a drill bit which includes a bit body, and a plurality of roller cones attached to the bit body and able to rotate with respect to the bit body. The bit also includes a plurality of cutting elements arranged on each of the roller cones so that cutting elements on adjacent cones intermesh between the adjacent cones. In this aspect, at least one of the cutting elements on each cone comprises a gage cutting element, and the gage cutting elements on each cone are arranged so that the scraping distance of the gage cutting elements on each cone is substantially the same as the scraping distance of the gage cutting elements on each of the other cones.

Dependencies are inferred from the claim text.