ROTATABLE CUTTING ELEMENTS AND RELATED EARTH-BORING TOOLS AND METHODS

摘要

Earth-boring tools may comprise rotatable cutting elements rotatably connected to protruding journals, which may be at least partially located within inner bores extending through the rotatable cutting elements. A rotationally leading end of one of the protruding journals may not extend beyond a cutting face of its associated rotatable cutting element. Alternatively, a protruding journal may comprise a chip breaker protruding from a cutting face of a rotatable cutting element. Methods of removing an earth formation may include directing cuttings forward, away from a cutting face of a rotatable cutting element then the cuttings reach an inner bore of the rotatable cutting element, and rotating the rotatable cutting element around a protruding journal at least partially located in the inner bore.

主权项

1. An earth-boring tool, comprising:
a body comprising blades extending radially outward to define a face at a leading end of the body, each blade comprising protruding journals at a rotationally leading end of each blade; and rotatable cutting elements rotatably connected to the protruding journals; one of the rotatable cutting elements comprising:
a substrate;a polycrystalline table attached to the substrate, the polycrystalline table being located on an end of the substrate; andan inner bore extending through the substrate and the polycrystalline table, wherein one of the protruding journals is at least partially located within the inner bore,wherein a rotationally leading end of the one of the protruding journals does not extend beyond a cutting face of the one of the rotatable cutting elements.