Fracture and wear resistant compounds and down hole cutting tools
AssigneeSmith International, Inc.
InventorDah-Ben Liang
Life of this patent
Estimating the term…
Abstract
Fracture and wear resistant cutting elements are provided. Examples include a cutting element formed of a wear resistant material having a binder composition and a coarse grain size such that the portion of the cutting element formed of the wear resistant material has a fracture toughness of at least about 18 ksi(in)0.5 and a wear number of at least about 1.8. In a particular example, the wear resistant material has a fracture toughness of at least about 20 ksi(in)0.5. A down hole cutting tool incorporating such cutting elements is also provided.
Claims37
A cutting element for a rock bit used to drill wellbores through earth formation, the cutting element comprising:
- wear resistant material, the wear resistant material comprising coarse grains disposed in a binder matrix;
- the coarse grains comprising grains of at least one selected from the group of a transition metal carbide, a transition metal boride, and transition metal nitride, the wear resistant material having a binder composition and a coarse grain size such that the wear resistant material has a fracture toughness of at least 20 ksi (in)0.5 and a wear number of at least 1.8.
A drill bit for drilling wellbores through earth formation, the drill bit comprising:
- a plurality of cutting elements mounted on a cutting structure, wherein at least one of the plurality of cutting elements comprises a wear resistant material, the wear resistant material comprising coarse grains disposed in a binder matrix, the coarse grains comprising grains of at least one selected from the group of a transition metal carbide, a transition metal boride, and transition metal nitride, the wear resistant material having a binder composition and a coarse grain size such that the wear resistant material has a fracture toughness of at least 20 ksi (in)0.5 and a wear number of at least 1.8.
A cutting element for a rock bit used to drill wellbores through earth formation, the cutting element, comprising:
- wear resistant material, the wear resistant material comprising coarse grains disposed in a binder matrix, the coarse grains comprising grains of at least one selected from the group of a transition metal carbide, a transition metal boride, and transition metal nitride, the wear resistant material having a binder composition and a coarse grain size such that the fracture toughness and the wear number of the wear resistant material generally follow the relationship:
- y=62.085·x(−1.3676)
- wherein y is the fracture toughness which is greater than or equal to 20 ksi (in)0.5, and x is the wear number, within a range defined by a coefficient of determination, R2, of about 0.86.
A drill, bit for drilling wellbores through earth formation, the drill bit;
- comprising:
- a plurality of cutting elements mounted on a cutting structure, wherein at least one of the plurality of cutting elements is formed from wear resistant material, the wear resistant material comprising coarse grains disposed in a binder matrix, the coarse grains comprising grains of at least one selected from the group of a transition metal carbide, a transition metal boride, and transition metal nitride, the wear resistant material having a binder composition and a coarse grain size such that the fracture toughness and the wear number generally satisfy the relationship:
- y=62.085·x(−1.3676),
- wherein y is the fracture toughness which is greater than or equal to 20 ksi (in)0.5, and x is the wear number, within a range defined by a coefficient of determination, R2, of about 0.86.
A drill bit used to drill wellbores through earth formation, the drill bit comprising:
- a plurality of cutting elements mounted on a cutting structure, wherein at least one of the plurality of cutting elements is formed of a wear resistant material comprising coarse grains of tungsten carbide disposed in a cobalt binder matrix, the tungsten carbide grains having an average grain size of around 9 μm, and the wear resistant material having a cobalt binder content of between about 10% and about 16% by weight.
Dependencies are inferred from the claim text.