Polycrystalline diamond compact bit with large-sized cutters
A polycrystalline diamond compact (PDC) bit with large-sized cutters includes: a bit body and a bit connecting component. The bit body is provided with blades, each of the blades has a gauge surface, and nozzles are defined on the bit body and are disposed between the blades; and the blades are provided with integral cutters respectively, each of the integral cutters covers a working surface of a corresponding one of the blades, a shape of each of the integral cutters matches with a crown shape of the corresponding one of the blades, and each of the integral cutters is installed on and fitted along the crown of the corresponding one of the blades. The bit achieves full coverage of the blades with cutters, which results in a lower cutter density under the same weight on bit.
1 . A polycrystalline diamond compact (PDC) bit with cutters, comprising: a bit body ( 3 ) and a bit connecting component ( 4 ),
wherein the bit body ( 3 ) is provided with blades ( 8 ), and nozzles ( 2 ) are defined on the bit body ( 3 ) and are disposed between the blades ( 8 ); and the blades ( 8 ) are provided with integral cutters ( 1 ) respectively, each of the integral cutters ( 1 ) covers a cutter installation working surface ( 10 ) of a corresponding one of the blades ( 8 ), a shape of each of the integral cutters ( 1 ) matches with a crown shape of the corresponding one of the blades ( 8 ), and each of the integral cutters ( 1 ) is installed on and fitted along the crown shape of the corresponding one of the blades ( 8 );
wherein each of the blades ( 8 ) comprises two side surfaces opposite to each other and an outer surface disposed between and connected to the two side surfaces, one of the two side surfaces defines a mounting slot, and each of the integral cutters ( 1 ) is installed in the mounting slot of the corresponding one of the blades ( 8 ); and
wherein the one of the two side surfaces is further provided with multiple conventional gauge cutters ( 5 ) thereon, and the multiple conventional gauge cutters ( 5 ) are separated from the integral cutters ( 1 ) installed in the mounting slot on the one of the two side surfaces.
2 . The PDC bit with cutters as claimed in claim 1 , wherein a back rake angle of each of the integral cutters ( 1 ) is in a range of 5-30°, the back rake angle is an angle between a working surface ( 11 ) of each of the integral cutters ( 1 ) and an outer normal line of a bit surface passing through a cutter positioning point, and back rake angles of the integral cutters ( 1 ) on the blades ( 8 ) are same or different to meet requirements for force balance.
3 . The PDC bit with cutters as claimed in claim 1 , wherein a diameter of each of the multiple conventional gauge cutters ( 5 ) is 13 millimeters (mm), a number of the multiple conventional gauge cutters ( 5 ) is in a range of 3-6, and a back rake angle of each of the multiple conventional gauge cutters ( 5 ) is in a range of 15-20°.
4 . The PDC bit with cutters as claimed in claim 1 , wherein the integral cutters ( 1 ) have a plurality of types, different types of the integral cutters ( 1 ) have different dimensions and/or different working surface shapes, the dimensions comprise: a length, a width, a thickness, and a size of chamfers on adjacent surfaces, and structures of the working surface shapes at least comprise: a planar surface structure, a wavy surface structure, and a serrated surface structure.
5 . The PDC bit with cutters as claimed in claim 1 , wherein types of the integral cutters ( 1 ) on the blades ( 8 ) are different, and lengths of the integral cutters ( 1 ) on the blades ( 8 ) are different to make working surfaces ( 11 ) of the integral cutters ( 1 ) fully cover a wellbore bottom to thereby achieve cutting to the wellbore bottom, and to make at least one of the blades ( 8 ) fully cover the wellbore bottom.
6 . The PDC bit with cutters as claimed in claim 5 , wherein a number of the blades ( 8 ) on the bit body ( 3 ) is five, a number of main blades ( 81 ) of the blades ( 8 ) is at least two, each of the main blades ( 81 ) of the blades ( 8 ) is mounted with a corresponding one of the integral cutters ( 1 ), and cutting surfaces of the main blades ( 81 ) of the blades ( 8 ) together are configured to fully cover the wellbore bottom.
7 . The PDC bit with cutters as claimed in claim 1 , wherein for each of the blades ( 8 ), the multiple conventional gauge cutters ( 5 ) are only disposed on the second part of the one of the two side surfaces, but not disposed on the outer surface or the other of the two side surfaces.
8 . The PDC bit with cutters as claimed in claim 1 , wherein a height ( 101 ) from a surface of each of the integral cutters ( 1 ) facing away from the bit body ( 3 ) to the outer surface of the corresponding one of the blades ( 8 ) is in a range of 2-3 mm.
9 . The PDC bit with cutters as claimed in claim 1 , wherein the one of the two side surfaces comprises a first part and a second part, the first part is closer to the nozzles ( 2 ) than the second part, the first part defines the mounting slot, the second part is a gauge surface ( 9 ), and the multiple conventional gauge cutters ( 5 ) are disposed on the gauge surface ( 9 ).
10 . A PDC bit with cutters, comprising: a bit body ( 3 ) and a bit connecting component ( 4 ),
wherein the bit body ( 3 ) is provided with blades ( 8 ), and nozzles ( 2 ) are defined on the bit body ( 3 ) and are disposed between the blades ( 8 ); and the blades ( 8 ) are provided with integral cutters ( 1 ) respectively, each of the integral cutters ( 1 ) covers a cutter installation working surface ( 10 ) of a corresponding one of the blades ( 8 ), a shape of each of the integral cutters ( 1 ) matches with a crown shape of the corresponding one of the blades ( 8 ), and each of the integral cutters ( 1 ) is installed on and fitted along the crown shape of the corresponding one of the blades ( 8 );
wherein each of the blades ( 8 ) comprises two side surfaces opposite to each other and an outer surface disposed between and connected to the two side surfaces, one of the two side surfaces comprises a first part and a second part, the first part is closer to the nozzles than the second part, the first part defines a mounting slot, and each of the integral cutters ( 1 ) is installed in the mounting slot of the corresponding one of the blades ( 8 ); and
wherein the second part of the one of the two side surfaces is a gauge surface ( 9 ), the gauge surface ( 9 ) defines one strip-shaped hole, and a strip-shaped gauge cutter ( 6 ) is installed in the strip-shaped hole.
11 . The PDC bit with cutters as claimed in claim 10 , wherein a thickness of the strip-shaped gauge cutter ( 6 ) is 6 mm, and a back rake angle of the strip-shaped gauge cutter ( 6 ) is in a range of 15°-20°.
12 . The PDC bit with cutters as claimed in claim 10 , wherein an inclination angle of the strip-shaped hole is in a range of 15°-20°.