Patent Application
20200087992
The present disclosure generally relates to a claw shaped gouging cutter for a fixed cutter drill bit.
U.S. Pat. No. 8,794,356 discloses an earth-boring tool including a body, one or more blades projecting outwardly from the body, and cutting elements carried by the blade. The cutting elements include at least one shearing cutting element and at least one gouging cutting element. Methods of forming an earth-boring tool include mounting a shearing cutting element including an at least substantially planar cutting face to a body of an earth-boring tool, and mounting a gouging cutting element including a non-planar cutting face to the body of the earth-boring tool. The gouging cutting element may be positioned on the body of the earth-boring tool such that the gouging cutting element will gouge formation material within a kerf cut in the formation material by the shearing cutting element, or between kerfs cut in the formation material by a plurality of shearing cutting elements.
U.S. Pat. No. 8,960,337 discloses a high impact resistant tool including a sintered polycrystalline diamond body bonded to a cemented metal carbide substrate at an interface, the body comprising a substantially pointed geometry with an apex, the apex comprising a curved surface that joins a leading side and a trailing side of the body at a first and second transitions respectively, an apex width between the first and second transitions is less than a third of a width of the substrate, and the body also includes a body thickness from the apex to the interface greater than a third of the width of the substrate.
The present disclosure generally relates a claw shaped gouging cutter for fixed cutter drill bit. In one embodiment, a cutter for use with a drill bit includes: a substrate for mounting in a pocket of the drill bit and made from a cermet material; and a head made from a superhard material, mounted to the substrate, and having a chisel or frusto-cone inclined relative to a longitudinal axis of the cutter by an attack angle ranging between fifteen and sixty degrees.
In another embodiment, a cutter for use with a drill bit includes: a substrate for mounting in a pocket of the drill bit and made from a cermet material; and a head made from the cermet material, mounted to the substrate, and having a chisel or frusto-cone inclined relative to a longitudinal axis of the cutter by an attack angle ranging between fifteen and sixty degrees.
So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments.
Alternatively, the head 3 may be made from a composite material, such as a cermet impregnated with superhard material, such as monocrystalline or thermally stable polycrystalline diamond. The cermet may be a cemented carbide and the diamond may be dispersed therein at a content ranging between twenty-five percent and sixty percent by volume. The gouging cutter 1 may then be manufactured by a hot isostatic pressing operation. Alternatively, the head 3 may be made from the same cermet material as the substrate 2.
The head 3 may have an interface 4 with the substrate 2, a chisel 5 at an end thereof opposite to the interface, a pedestal 3p extending from the interface and connecting a side 5s of the chisel to the interface, and a dome segment 3d connecting a base 5b of the chisel to the pedestal. The substrate 2 may have the interface 4 with the head 3 and a mounting end opposite to the interface for being received in a pocket of a drill bit 7. The mounting end of the substrate 2 may have a chamfer 2c formed in a periphery thereof. The interface 4 may be planar or non-planar.
The pedestal 3p may have a frusto-conical portion extending from the interface 4 and an irregular portion extending from the frusto-conical portion to the dome segment 3d and to a side 5s of the chisel 5. The chisel 5 may resemble a frusto-cone with the side 5s having a truncated portion adjacent to the pedestal 3p, the base 5b having a truncated portion adjacent to the dome segment 3d, and an edge 5e formed by a pair of flats 5f formed into opposite non-truncated portions of the side. The edge 5e may be planar. The planar edge 13e may have a slight curvature. The edge 5e may have a length 6e ranging between one percent and thirty percent of a diameter of the substrate 2, ranging between five percent and thirty percent thereof, or ranging between ten percent and thirty percent thereof. The edge 5e may have a width 6w ranging between one percent and sixty percent of the length 6e thereof or ranging between ten percent and sixty percent thereof.
The chisel 5 may have an axis 6c perpendicular to the edge 5e and the base 5b and inclined relative to a longitudinal axis 6g of the gouging cutter 1 by an attack angle 6a ranging between fifteen and sixty degrees. The flats 5f may be formed in the chisel 5, such as by laser cutting or electrical discharge machining, after the gouging cutter 1 has been sintered. The head 3 may have a height 6h greater than or equal to a thickness 6t of the substrate 2 and less than or equal to the diameter of the substrate. The gouging cutter 1 may be symmetrical about a longitudinal plane extending through the edge 5e.
Alternatively, the flats 5f may be roughly formed during sintering and finished by laser cutting or electrical discharge machining.
Alternatively, the bit body 8 may be metallic, such as being made from steel, and may be hardfaced. The metallic bit body may be connected to a modified shank by threaded couplings and then secured by a weld or the metallic bit body may be monoblock having an integral body and shank.
The cutting face 9 may include one or more (three shown) primary blades 11p, one or more (three shown) secondary blades 11s, fluid courses formed between the blades, and the gouging cutters 1, 1a, 1b. The cutting face 9 may have one or more sections, such as an inner cone 12c, an outer shoulder 12s, and an intermediate nose 12n between the cone and the shoulder sections. The blades 11 may be disposed around the cutting face 9 and each blade may be formed during molding of the bit body 8 and may protrude from a bottom of the bit body. The primary blades 11p and the secondary blades 11s may be arranged around the cutting face 9 in an alternating fashion. The primary blades 11p may each extend from a center of the cutting face, across a portion of the cone section 12c, across the nose 12n and shoulder 12s sections, and to the gage section 10. The secondary blades 11s may each extend from a periphery of the cone section 12c, across the nose 12n and shoulder 12s sections, and to the gage section 10. Each blade 11 may extend generally radially across the portion of the cone section 12c (primary only) and nose section 12n with a slight spiral curvature and across the shoulder section 12s radially and longitudinally with a slight helical curvature. Each primary blade 11p may be inclined in the cone section 12c by a cone angle. The cone angle may range between five and forty-five degrees.
Each blade 11 may have a bearing face 11f extending between a leading edge and a trailing edge thereof. Each blade 11 may be made from the same material as the lower portion of the bit body 8. The leading gouging cutters 1a may be mounted, such as by brazing or interference fit, in respective leading pockets formed in the in the bearing faces 11f of the primary blades 11p adjacent to the leading edges thereof. The leading gouging cutters 1a may be mounted into the leading pockets after infiltration of the bit body 8. The gouging cutters 1 may be mounted, such as by brazing or interference fit, in respective pockets formed in the in the bearing faces 11f of the secondary blades 11s midway between leading edges and trailing edges thereof. The gouging cutters 1 may be mounted into the pockets after infiltration of the bit body 8.
Starting in the nose section 12n, each primary blade 11p may have a row of backup pockets formed in the bearing face 11 f thereof adjacent to the trailing edge thereof and extending therealong through most of the shoulder section 12s. Each backup pocket may be located to straddle a gap formed between adjacent leading pockets. The backup gouging cutters 1b may be mounted into the backup pockets after infiltration of the bit body 8 and may be mounted by brazing or interference fit. The longitudinal axis 6g of each gouging cutter 1, 1a, 1b may be transverse to a projection of the respective bearing face 11f through the respective pocket, such as perpendicular or substantially perpendicular (plus or minus ten degrees forward rake angle). An effective forward rake angle of each gouging cutter 1, 1a, 1b may be determined by the sum of the forward rake angle and the attack angle 6a thereof.
Each blade 11 may have an orientation guide (not shown), such as a hole, formed in the bearing face 11f thereof adjacent to each pocket. During mounting, a technician or robot may align a back of the edge 5e of each gouging cutter 1, 1a, 1b with the respective orientation guide, thereby ensuring the proper orientation of the gouging cutter. The proper orientation may be where a projection from the edge 5e intersects the bearing face 11f at a point closest to the respective leading edge. Positions of the gouging cutters 1, 1a, 1b may be staggered across the blades 11 to obtain complete and overlapping coverage.
One or more ports (not shown), such as a port for each blade 11, may be formed in the bit body 8 and each port may extend from the plenum and through the bottom of the bit body to discharge drilling fluid (not shown) along the fluid courses. A nozzle (not shown) may be disposed in each port and fastened to the bit body 8. Each nozzle may be fastened to the bit body 8 by having a threaded coupling formed in an outer surface thereof and each port may be a threaded socket for engagement with the respective threaded coupling. The ports may include an inner set of one or more ports disposed in the cone section 12c and an outer set of one or more ports disposed in the nose section 12n and/or shoulder section 12s. Each inner port may be disposed between an inner end of a respective secondary blade 11s and the center of the cutting face 9.
The gage section 10 may define a gage diameter of the drill bit 7. The gage section 10 may include a plurality of gage pads, such as one gage pad for each blade 11, and junk slots formed between the gage pads. The junk slots may be in fluid communication with the fluid courses formed between the blades 11. The gage pads may be disposed around the gage section 10 and each pad may be formed during molding of the bit body 8 and may protrude from the outer portion of the bit body. Each gage pad may be made from the same material as the bit body 8 and each gage pad may be formed integrally with a respective blade 11. Each gage pad may extend upward from an end of the respective blade 11 in the shoulder section 12s to an exposed outer surface of the shank. Each gage pad may include a transition portion located adjacent to the shoulder section 12s, a full diameter portion extending from the transition portion, and a tapered portion extending from the full diameter portion to the shank.
Alternatively, the gage pads may have gage protectors embedded therein. Each gage protector may be a thermally stable polycrystalline diamond.
In use (not shown), the drill bit 7 may be assembled with one or more drill collars, such as by threaded couplings, thereby forming a bottomhole assembly (BHA) (not shown). The BHA may be connected to a bottom of a pipe string, such as drill pipe or coiled tubing, thereby forming a drill string. The BHA may further include a steering tool, such as a bent sub or rotary steering tool, for drilling a deviated portion of the wellbore. The pipe string may be used to deploy the BHA into the wellbore. The drill bit 7 may be rotated, such as by rotation of the drill string from a rig (not shown) and/or by a drilling motor (not shown) of the BHA, while drilling fluid, such as mud, may be pumped down the drill string. A portion of the weight of the drill string may be set on the drill bit 7. The drilling fluid may be discharged by the nozzles and carry cuttings up an annulus formed between the drill string and the wellbore and/or between the drill string and a casing string and/or liner string.
As the drill bit 7 engages a rock formation (not shown) adjacent to the wellbore, each gouging cutter 1, 1a, 1b may gouge and/or crush the formation. As compared to conventional shear cutters, the gouging cutters 1, 1a, 1b may be mounted in pockets transverse to the bearing face 11f instead of parallel thereto, thereby allowing more cutters to be mounted onto a given blade 11. The transverse mounting of the gouging cutters 1, 1a, 1b are much easier to braze into the respective pockets than conventional shear cutters and result in a better bond therein. Further, the gouging cutters 1, 1a, 1b have a much greater height than the thickness of conventional shear cutters, thereby providing greater protection to the bearing faces 11f once the cutters become worn.
Alternatively, the secondary blades 11s may have backup cutters similar to the primary blades 11p. Alternatively, the blades 11 may have shear cutters as the leading cutters instead of the gouging cutters 1, 1a.
Alternatively, the substrate 2 may have a knob (not shown) mounted to a back face thereof for orienting the gouging cutters 1, 1a, 1b. The knob may be formed separately from the rest of the gouging cutter 1, 1a, 1b and then mounted to the substrate thereof, such as by brazing. The knob may be angularly offset from the edge 5e, such as being located opposite therefrom (one-hundred eighty degrees therefrom). The knob may be hemi-spherical and have a diameter ranging between twenty-five and forty-five percent of a diameter of the back face. Instead of an orientation guide adjacent to each pocket, the drill bit 7 may have a dimple (not shown) formed in the pocket thereof for mating with the knob, thereby ensuring that the gouging cutter 1, 1a, 1b has been properly oriented. The knob may be made from the same material as the substrate or a different material than the substrate, such as a metal or alloy, such as steel.
Alternatively, the substrate 2 may have a keyway (not shown) formed therein for orienting the gouging cutters 1, 1a, 1b. The keyway may be located at an edge of the substrate 2 and may extend from the back face thereof along a portion of a side thereof. The keyway may be a slot inclined relative to a longitudinal axis 6g by an angle ranging between ten and seventy degrees. Instead of an orientation guide adjacent to each pocket, the drill bit 7 may have a mating key (not shown) formed in the pocket and the slot may have a width corresponding to a diameter of the mating key. The keyway may be angularly offset from the edge 5e, such as being located opposite therefrom.
The head 17 may have the interface 4 with the substrate 16, a chisel 18 at an end thereof opposite to the interface, a pedestal 17p extending from the interface and connecting a side 18s of the chisel to the interface, and a dome segment 17d connecting a base 18b of the chisel to the pedestal. The substrate 16 may have the interface 4 with the head 17 and a mounting end opposite to the interface for being received in a pocket of the drill bit 7 instead of the gouging cutters 1, 1a, 1b. The mounting end of the substrate 16 may have the chamfer 2c formed in a periphery thereof.
The pedestal 17p may have a frusto-conical portion extending from the interface 4 and an irregular portion extending from the frusto-conical portion to the dome segment 17d and to a side 18s of the chisel 18. The chisel 18 may resemble a frusto-cone with the side 18s having a truncated portion adjacent to the pedestal 17p, the base 17b having a truncated portion adjacent to the dome segment 17d, and an edge 18e formed by a pair of flats 18f formed into opposite non-truncated portions of the side. The edge 18e may be sharp. The edge 18e may have a length (see 6e in
The chisel 18 may have an attack angle (see 6a in
The attack angle 6a of the gouging cutter 1 may be thirty-five degrees as shown while the attack angle of the third gouging cutter 15 may be twenty-five degrees as shown. The dome 17d and pedestal 17p differ accordingly with respect to the dome 3d and pedestal 3p.
Alternatively, the third gouging cutter 15 may have either the planar edge 5e or the wedge-shaped edge 14e instead of the sharp edge 18e. Alternatively, the gouging cutter 1 may have the sharp edge 18e instead of the planar edge 5e. The sharp edge 18e may perform better during drilling of softer formations, the planar edge 5e may perform better during drilling of harder formations, and the wedge-shaped edge 14e may perform better during drilling of intermediate hardness formations. The planar edge 5e may have better impact resistance than the wedge-shaped edge 14e and the wedge-shaped edge may have better impact resistance than the sharp edge 18e.
Alternatively, the drill bit 7 may have a first set of one of the gouging cutters 1, 13, 15, 19 in the cone section 12c, a second set of a different one of the gouging cutters in the nose section 12n, and a third set of another different one of the gouging cutters in the shoulder section 12s.
The priority provisional application U.S. 62/732,048, filed on Sep. 17, 2018, is herein incorporated by reference in its entirety.
While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope of the invention is determined by the claims that follow.
| Number | Date | Country | |
|---|---|---|---|
| 62732048 | Sep 2018 | US |
