Rotary Drag Bit
AssigneeUlterra Drilling Technologies, L.P.
InventorsCraig Knull, Jason Maw
Life of this patent
Estimating the term…
Abstract
A rotary drag bit has one or more fixed composite cutting structures formed from a plurality of discrete prefabricated cutters that abut each other along complementary side surfaces, the composite cutting structure being placed and oriented on the cutting face of the rotating body so that the composite cutting structure presents a cutting profile that does not expose any portion of the cutting face that is between or behind the composite cutting structure, with respect to the direction of travel of the composite cutting structure during boring, to the uncut earth formation as the body is rotated during boring.
Claims15
A downhole tool for boring earth formations, comprising:
- a body with a cutting face, the body having a central axis around which the body is rotated for boring an earth formation;
- and
- a plurality of discrete prefabricated cutters mounted to the cutting face in a row, each of the plurality of discrete prefabricated cutters projecting outwardly from the face and positioned to present a cutting surface for engaging at least a bottom of a bore hole in an earth formation when the body is rotated on its central axis within a bore hole;
- wherein at least one pair of cutters of the plurality of discrete prefabricated cutters abut each other along complementary side surfaces to form a composite cutting structure, the composite cutting structure presenting a cutting profile that does not expose any portion of the bit body between or behind the at least one pair of cutters to abrasion by the earth formation when the body is rotated during boring of the earth formation.
A rotary drill bit for earth boring, comprising:
- a body with a cutting face, the body having a central axis around which the body is rotated in a predetermined direction of rotation for boring an earth formation;
- the cutting face having at least two blade portions extending from the central axis to a peripheral edge of the cutting face, each of the at least two blades having a row of discrete prefabricated cutters mounted along leading edges of the blade and projecting generally outwardly in the direction of rotation, each of the cutters in each of the rows having a cutting surface positioned for engaging an earth formation when the body is rotated on its central axis within the earth formation;
- wherein at least two cutters that are adjacent to each other in each of the rows of cutters abut each other along complementary side surfaces to form a composite cutting element that presents a cutting profile that does not expose any portion of the bit body cutting face between or behind the cutters to abrasion by the earth formation when the body is rotated during boring of the earth formation.
Dependencies are inferred from the claim text.