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Jet bit

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Publication number
US3175629A
US3175629A US23480862A US3175629A US 3175629 A US3175629 A US 3175629A US 23480862 A US23480862 A US 23480862A US 3175629 A US3175629 A US 3175629A
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Prior art keywords
bit
member
lower
nozzles
passageway
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David S Rowley
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JERSEY PROD RES CO
JERSEY PRODUCTION RESEARCH Co
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JERSEY PROD RES CO
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    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B21/00Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
    • E21B21/002Down-hole drilling fluid separation systems
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00Drill bits
    • E21B10/46Drill bits characterised by wear resisting parts, e.g. diamond inserts
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00Drill bits
    • E21B10/60Drill bits characterised by conduits or nozzles for drilling fluids

Description

March 30, 1965 D. s. ROWLEY JET BIT Filed Nov. 1, 1962 David S. Rowley INVENTOR.

BY %M) t. QuA

ATTORNEY United States Patent 3,175,629 JET BIT David S. Rowley, Salt Lake City, Utah, assignor to Jersey Production Research Company, a corporation of Delaware Filed Nov. 1, 1962, Ser. No. 234,808 5 Claims. (Cl. 175329) The present invention relates to rotary bits for drilling boreholes in the earth and is particularly concerned with an improved jet bit useful for drilling oil wells, gas wells and similar boreholes.

Jet bits provided with nozzles through which drilling fluid can be discharged at high velocity against the formation at the bottom of the borehole have been used in the petroleum industry to permit more effective scouring of the formation and to promote more efficient entrainrnent of solids in the fiuid. The nozzles employed in such bits must have small diameters to achieve the required velocities and are therefore readily plugged by solid articles of only moderate size. This precludes the injection through such bits of materials normally used to control lost circulation. Each time such a material were employed, the drill string would have to be pulled from the borehole and the bit removed. The pipe would then have to be returned to the hole and the lost circulation material injected. After circulation had been restored,

the pipe would have to be pulled from the hole, the bit replaced, and the drill string again lowered into place. Repeated trips into and out of the borehole are hazardous where lost circulation problems exist because of the possibility that a blowout may occur during tripping. For this reason, the use of jet bits has been restricted.

It is therefore an object of the present invention to provide an improved jet bit for drilling oil wells, gas wells and similar boreholes. A further object is to provide a jet bit which will permit the injection of lost circulation materials into a borehole without the necessity of repeated trips to and from the surface. Another object is to provide a jet bit through which lost circulation materials can be injected without plugging the bit nozzles. Still other objects will be apparent from the following detailed description of bits constructed in accordance with the invention and from the accompanying drawing, in which:

FIGURE 1 is a vertical elevation, partially in section, of a diamond bit constructed in accordance with the invention; and,

FIGURE 2 is a bottom view of the bit of FIGURE 1.

The bit shown in FIGURE 1 of the drawing is a diamond bit which includes a tubular upper body section 11 of steel or similar metal having an upper shank 12 provided with external threads 13. The upper shank and threads on the bit shown form a standard A.P. I. tool joint pin which is used to attach the bit to the lower end of a conventional rotary drill string. Other suitable connecting means may be provided if desired. The upper body section contains an internal passageway 14 which extends downwardly along the longitudinal axis of the tool from an opening at the top of the upper shank. The diameter of the internal passageway is enlarged below a tapered shoulder 15 located beneath the shank. Lower body section 16 is a tubular member attached to the lower end of the upper body section by means of threads 17. An O-ring or similar member 18 is set in a groove in the inner surface of the lower body member below the thread to provide a seal between the two sections. The outer diameter of the lower body section is enlarged below a tapered external shoulder 19. Threads 20 are provided for attaching the lower body section to the cutting head or crown of the bit. The use of an upper and a lower 3,175,629 Patented Mar. 30, 1965 body section as described permits ready access to the interior of the bit but is not essential. In some cases the body member may be made in one piece.

The crown of the bit shown in FIGURE 1 of the drawin-g includes a steel blank 21 provided with threads which mate with those on the lower end of the lower body memher. The steel blank and lower body member are normally welded together after the bit has been assembled, the weld being indicated by reference numeral 22. A matrix section 23 is bonded to the lower part of the steel blank in order to provide the desired bit contour. A typical matrix may consist of a copper-nickel alloy-containing powdered tungsten carbide in quantities sufiicient to confer the required strength and erosion resistance. Other matrix compositions and methods for fabricating diamond bits utilizing them are described in the Diamond Drill.

Handboo by I. D. Cumming, 1956 edition, published by J. K. Smit & Sons of Canada, Limited, Toronto. The portion of the crown formed by the matrix section includes a tapered shoulder 24 and an outer gage surface 25 located below the shoulder. The crown is rounded below the gage Surface to form a generally convex drilling face 2 6 containing a shallow cavity located near the longitudinal axis of the bit. This cavity, indicated generally by reference numeral 27, results in the formation of a short conical rock projection beneath the bit. This helps center the bit in the borehole and provides additional surface for the placement of diamonds near the bit axis. The diamonds employed as cutting elements are embedded in the gage surface and drilling face and are designated by reference numeral 28. Tungsten carbide chips or similar hard, abrasion-resistant particles may be utilized in lieu of diamonds in some instances.

rial bonded to the wall of the passageway below the shoulder. The internal diameter of nozzle 31 is sufiiciently large to permit the passage of lost circulation materials which may have to be injected through the bit.

The passageway below the nozzle opens into a discharge port in the lower surface of the tool. The port is of irregular cross-section as shown in FIGURE 2 of the drawing, thus providing a crows foot for drilling out the formation beneath the bit axis. watercourses 32 extend from the port across the bottom of the bit and up the gage surface. Junk slots 33 are spaced at regular intervals around the periphery of the tool to permit the discharge of large particles dislodged from the formation beneath it. Each junk slot is connected to one of the ports near the bit axis by a short connecting watercourse 34. Jet nozzles 35 are mounted in opening in the crown and discharge into the junk slots. The jet nozzles are made of tungsten carbide or similar material and are of somewhat smaller internal diameter than nozzle 31 and the discharge port discussed above. Each of the jet nozzles discharges from an annular recess 36 within the crown.

An internal nozzle and screen assembly is provided above lower nozzle 31 in the bit shown in FIGURE 1.

This assembly forms a first passageway extending longitudinally through the tool from the opening in shank 12 to the discharge port in the crown and a second, annular passageway extending from an inlet in the first passageway to the openings in the crown within which the jet nozzles 35 are mounted. The nozzle assembly shown includes a lower connecting member 37 which seats against shoulder 30 in the crown. The connecting member has an external shoulder 38 which bears against the upper surface of the portion of the crown surrounding the central passageway 29. An O-ring or similar member 39 is set in a groove below'the shoulder to effect a seal between the connecting member and crown. The upper end of the connecting member is provided with internal threads 40. Shoulders 41 and 42 are located below the threads. A spacer 43 is shown in position on the lower shoulder 42. An Q-ring 44 is set in a groove between the two shoulders and provides a seal between the spacer and the inner wall of the connecting member. 'As will be pointed out in greater detail hereinafiter, the spacer can be replaced with a nozzle of tungsten carbide or similar erosion resistant material if desired A nozzle retainer 45 is located in the nozzle assembly above the lower connecting member. The retainer is' and is provided with an O-ring 46 to prevent the escape of fluids bet-ween the two. Internal nozzle 47 is seated on an internal shoulder 48 within the retainer. As' can be seen horn the drawing, the throat diameter of this nozzle is similar to that of discharge nozzle 3 1 land is considerably larger than the jet nozzle set inthe lower part of the crown. An O-ring 49 provides a seal between the nozzle and surrounding retainer. Internal threads 50 located above an internal shoulder '51 permit the connection of a second retainer to the upper end of the retainer described. It will be seen from the drawing that three additional nozzle retainers 52, 53 and 54 containing nozzles 55, S6 and. 57 are provided in the assembly. These are identical to the lower retainer and nozzle and therefore need not be described in detail.

- The uppermost nozzle retainer 54 is connected to the lower end or a cylindrical screen retainer 58 by means of threads 59. O-ring 60 is set in a groove above the threads to provide a seal between the two. The screen retainer contains longitudinal slots 61 through which fluid may pass outwardly into thc'annular space 62 between the retainer and the inner wall of theupper body section. A cylindrical, slot-ted screen 63 seats again-stan internal shoulder 64 in the lower part of the screen retainer and extends upwmdly to the upperend of the retainer above the slots. Screens other than the slotted type shown 7 may be employed. In some the use of a separate screen may be avoided by providing very small openings in member 58 but the use of a separate screen and retainer is preferred. Annular cap 65 is connected to theupper a closure for the annular space between the screen retainer and the inner wall of the upper body section below tapered shoulder It is not essentialthat this closure be absolutely fluid tight and hence no sealing member is provided. It preferred that the screen, screen retainer, internal'nozzles and nozzle retainer all be made,

of tungsten carbide or a similar erosion-resistant material. It will be apparent that internal nozzle and screen assembly designs other than that described above may be employed if desired. In some instances, fior example, it may be preferred to mount the internal nozzles and screen within a tube of tungsten carbide or similar material held in place near the top and bottom of the body member. In other cases it may be desirable to mount the nozzles and screen in place permanently and dispense with the seals,

threads and f other r eatures required with a replaceable screen and nozzles. These and similar modifications will be apparent to [those skilled iii-the art.

During-a rotarydrill-ing operation utilizing the tool shown in the drawing, drilling fluid is circulated downwardly to the bit through the'r drill string to which it is connected; After passing. through passageway 14 in the shank of the upper body section, the fluid flows through the opening in annular cap 6-5 on the internal nozzle as sembly. A part of the fluid thus introduced into the nozzle assembly passes downwardly through the internal nozzles and isdischarged beneath the tool. The internal nozzles reduce the velocity of the fluid so that it emerges from the discharge ports at the bottom of the bit at relatively low velocity. This avoids undue erosion of the crows foot and adjacent sections of the crown and at the same time permits the of suflicient fluid pressure to secure the required high velocity through the jet nozzles. The use of a'plurality of verti-callyaspaoed internal nozzles as shown also makes possible the use or considerably larger nozzles than could otherwise be employed. The number of vertically-spaced nozzles utilized will depend in part upon the pressure at which drilling fluid is supplied to the bit, the fluid throughput desired, and the pressure drop across the jet nozzles. If necessary, spacers may be substituted for one or more of the nozzles provided. Alternatively, an additional'nozzle may be substituted for spacer-'43 in the bit shown. It is generally preferred to employ a maximum number of internal nozzles and thus maintain the internal nozzle diameters as large as possible.

A part of the fluid introduced into the nozzle assembly through the opening in cap 65 .do'es'not pass through the internal nozzles and instead is forced through the openings in screen 63 and the slots 61 in the screen retainer. This fluid flows downwardly through the annular space 62 between the internal nozzle assembly and the inner wall of the upper body section to the'jet nozzles in the lower part of the bit. Oomparatively little pressure drop occurs in the annular space and hence the pressure drop across the jet nozzles is This results in thedischarge of fluid at high velocity'against the tor-mation at the bottom of the borehole. Each of the jet nozzles is preferably set at a different angle to the longitudinal axis of the bit so that substantially all of the formation beneath the bitis thoroughly secured by the high velocity fluid as the bit rotates. In most about 50% of the total fluid circulated o tth-e bit will be dis-charged through the jet nozzles. The distribution or fiuidbetween the jet nozzles and theinterhal nozzle assembly can be readily controlled by varying the member of nozzles and the noz end of the retainer by means of threads 66 to provide zle diameters in the internal nozzle assembly. The addition of an internal nozzle to the assembly will increase the pressure drop through the assembly and hence cause a larger proportion of the total fluid to pass through the jet-nozzles. The removal of a nozzle from the assembly at the center of the bit will reduce the pressuredrop and permit a greater fraction. of. the total fluid to be discharged into the borehole through the discharge port near the longitudinal-axis or the tool; In like manner, a reduction in the. internalnozzlediameters increases the pressure drop in the assembly, resulting in the discharge of more fluid through the jet nozzles; while an increase in internal nozzle diameter reduces the proportionate amount of fluid discharged through the jet nozzles.

When the injection of a lost circulation material into vugs or fractures in the formation surrounding the borehole becomes necessary, the material may be entrained in the drilling mud or other fluid at the surface and circulated downwardly through the drill string without interrupting the drilling operation. -The particles of lost circulation material pass through the relatively-large internal nozzles in the body of the bit and are discharged beneath the tool. Thescreen in the upper body section of the bit prevents entrainment of the particles in fluid passing through the annular section of the tool to the jet nozzles and hence plugging of the nozzles is avoided. Particles trapped by the screen are continuously carried away by the fluid passing downwardly within the internal nozzle and screen assembly. The.screen is, thus essentially selfcleaning. After the required quantity of lost circulation material has been injectedintothe formation and circu- The invention has been described above in terms of a diamond bit but is equally applicable to rock bits, drag bits and other rotary drilling tools. By simply replacing the diamond cutting elements on the bit shown with roller cones supported on legs extending downwardly from the body or with drag bit blades, the invention can readily be applied to a rock bit or drag bit. The internal nozzle and screen assembly may be identical to that shown in the drawing. The modifications required to thus adapt the invention to other type bits are minor and will be apparent to those skilled in the art.

What is claimed is:

1. A rotary drill bit comprising:

a body member provided with means for connecting said member to the lower end of a rotary drill string, said body member containing a first longitudinal passageway extending from an opening at the upper end of said member to a discharge port at the lower end of said member near the longitudinal axis thereof and a second longitudinal passageway extending from an inlet in said first passageway near the upper end thereof to an outlet near the lower end of said body member laterally spaced from said discharge port;

means within said first passageway at vertically-spaced intervals between said inlet and said discharge port for increasing the pressure drop therein and reducing the velocity with which fluid emerges from said discharge port;

means within said second passageway near the lower end thereof for increasing the velocity with which fluid is discharged from said outlet;

means within said body member for restricting the passage of solids from said first passageway through said inlet into said second passageway;

and cutting elements mounted at the lower end of said body member.

2. A rotary drill bit comprising:

a body member provided with means for connecting said member to the lower end of a rotary drill string and with a lower face for engaging the formation at the bottom of a borehole, said body member containing a first longitudinal passageway extending from an opening near the upper end of said member to a discharge port in said lower face near the longitudinal axis of said member and a second longitudinal passageway extending from an inlet in said first passageway near the upper end thereof to an outlet in said lower face laterally spaced from said discharge port;

means within said first passageway at vertically-spaced intervals between said inlet and said discharge port for increasing the pressure drop therein and reducing the velocity with which fluid emerges from said discharge port;

means within said second passageway near the lower end thereof for increasing the velocity with which fluid is discharged from said outlet;

means within said body member for restricting the passage of solids from said first passageway through said inlet into said second passageway;

and a plurality of particulate cutting elements embedded in said lower face of said body member.

3. A rotary drill bit comprising:

a body member provided with means for connecting said member to the lower end of a rotary drill string and with a crown for engaging the formation at the bottom of a borehole, said body member containing a first longitudinal passageway extending from an opening near the upper end of said member to a discharge port in said crown near the longitudinal axis of said member and a second longitudinal passageway extending from an inlet in said first passageway near the upper end thereof -to a plurality of outlets in said crown laterally spaced from said discharge P a screen within said body member for restricting the passage of solids from said first passageway through said inlet into said second passageway;

a plurality of erosion-resistant nozzles mounted at vertically-spaced intervals in said first passageway above said discharge port and below said inlet for increasing the pressure drop therein and reducing the velocity at which fluid emerges from said discharge port;

a plurality of jet nozzles mounted in said outlets near the lower surface of said crown for increasing the velocity with which fluid is discharged from said second passageway;

and a plurality of diamonds embedded in the lower surface of said crown.

4. A bit as defined by claim 3 wherein at least one of said erosion-resistant nozzles is removably mounted in said first passageway.

5. A rotary drill bit comprising:

a hollow body member provided with means for connecting said member to the lower end of a rotary drill string and with a crown for engaging the formation at the bottom of a borehole, said body member containing an opening in the upper end thereof, a discharge port in said crown near the longitudinal axis of said member, and a plurality of outlets in said crown laterally spaced from said discharge port;

a tubular nozzle and screen assembly mounted within said body member to form a first longitudinal passageway extending through said assembly to said discharge port and a second longitudinal passageway extending to said outlets from a lateral opening in said assembly near the upper end thereof, said assembly including a screen over said lateral opening therein and a plurality of erosion-resistant nozzles verticallyspaced between said lateral opening and said discharge port to increase the pressure drop therein and reduce the velocity with which fluid emerges from said discharge port;

a plurality of jet nozzles mounted in said outlets near the lower surface of said crown for increasing the velocity with which fluid is discharged from said outlets;

and a plurality of diamonds embedded in the lower surface of said crown.

References Cited by the Examiner UNITED STATES PATENTS 2,293,259 8/42 Johnson 175-340 X 3,112,803 12/63 Rowley 175329 FOREIGN PATENTS 456,140 11/36 Great Britain.

CHARLES E. OCONNELL, Primary Examiner.

BENJAMIN HERSH, Examiner.

Claims (1)

1. A ROTARY DRILL BIT COMPRISING: A BODY MEMBER PROVIDED WITH MEANS FOR CONNECTING SAID MEMBER TO THE LOWER END OF A ROTARY DRILL STRING, SAID BODY MEMBER CONTAINING A FIRST LONGITUDINAL PASSAGEWAY EXTENDING FROM AN OPENING AT THE UPPER END OF SAID MEMBER TO A DISCHARGE PORT AT A LOWER END OF SAID MEMBER NEAR THE LONGITUDINAL AXIS THEREOF AND A SECOND LONGITUDINAL PASSAGEWAY EXTENDING FROM AN INLET IN SAID FORST PASSAGEWAY NEAR THE UPER END THEREOF OF AN INLET NEAR THE LOWER END OF SAID BODY MEMBER LATERALLY SPACED FROM SAID DISCHARGE PORT; MEANS WITHIN SAID FIRST PASSAGEWAY AT VERTICALLY-SPACED INTERVALS BETWEEN SAID INLET AND SAID DISCHARGE PORT FOR INCREASING THE PRESSURE DROP THEREIN AND REDUCING
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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3322214A (en) * 1963-12-26 1967-05-30 Phillips Petroleum Co Drilling method and apparatus
US3358783A (en) * 1964-06-04 1967-12-19 Aquitaine Petrole Abrasive resistant elements for the vents of rotatable drilling tools and method of manufacture
US3727704A (en) * 1971-03-17 1973-04-17 Christensen Diamond Prod Co Diamond drill bit
US4176723A (en) * 1977-11-11 1979-12-04 DTL, Incorporated Diamond drill bit
EP0033654A2 (en) * 1980-02-02 1981-08-12 DRILLING & SERVICE U.K. LIMITED Rotary drill bits and method of use
EP0043609A1 (en) * 1980-07-04 1982-01-13 Shell Internationale Research Maatschappij B.V. Rotary bit with jet nozzles
FR2490106A1 (en) * 1980-09-12 1982-03-19 Christensen Inc Fluid filter has internal circulation for preventing the clogging of nozzles and orifices, in particular for drilling tools
US4554986A (en) * 1983-07-05 1985-11-26 Reed Rock Bit Company Rotary drill bit having drag cutting elements
EP0171852A1 (en) * 1984-08-06 1986-02-19 Shell Internationale Research Maatschappij B.V. Rotary drill bit
US20040245840A1 (en) * 2002-09-12 2004-12-09 Tubergen Renard G. Seating with comfort surface
US20060071522A1 (en) * 2003-06-05 2006-04-06 Steelcase Development Corporation Control for seating unit with back stop
US20100263875A1 (en) * 2009-04-15 2010-10-21 Williams Adam R Drilling systems for cleaning wellbores, bits for wellbore cleaning, methods of forming such bits, and methods of cleaning wellbores using such bits
US20150136493A1 (en) * 2013-11-20 2015-05-21 Longyear Tm, Inc. Drill Bits Having Blind-Hole Flushing And Systems For Using Same

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB456140A (en) * 1934-05-29 1936-11-03 Chicago Pneumatic Tool Co Rotary drilling bit
US2293259A (en) * 1941-03-25 1942-08-18 Acme Fishing Tool Company Device for preventing clogging of drilling bits
US3112803A (en) * 1962-01-02 1963-12-03 Jersey Prod Res Co Diamond drill bit

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB456140A (en) * 1934-05-29 1936-11-03 Chicago Pneumatic Tool Co Rotary drilling bit
US2293259A (en) * 1941-03-25 1942-08-18 Acme Fishing Tool Company Device for preventing clogging of drilling bits
US3112803A (en) * 1962-01-02 1963-12-03 Jersey Prod Res Co Diamond drill bit

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3322214A (en) * 1963-12-26 1967-05-30 Phillips Petroleum Co Drilling method and apparatus
US3358783A (en) * 1964-06-04 1967-12-19 Aquitaine Petrole Abrasive resistant elements for the vents of rotatable drilling tools and method of manufacture
US3727704A (en) * 1971-03-17 1973-04-17 Christensen Diamond Prod Co Diamond drill bit
US4176723A (en) * 1977-11-11 1979-12-04 DTL, Incorporated Diamond drill bit
EP0033654A2 (en) * 1980-02-02 1981-08-12 DRILLING & SERVICE U.K. LIMITED Rotary drill bits and method of use
EP0033654A3 (en) * 1980-02-02 1981-10-21 DRILLING & SERVICE U.K. LIMITED Rotary drill bits and method of use
EP0043609A1 (en) * 1980-07-04 1982-01-13 Shell Internationale Research Maatschappij B.V. Rotary bit with jet nozzles
FR2490106A1 (en) * 1980-09-12 1982-03-19 Christensen Inc Fluid filter has internal circulation for preventing the clogging of nozzles and orifices, in particular for drilling tools
US4554986A (en) * 1983-07-05 1985-11-26 Reed Rock Bit Company Rotary drill bit having drag cutting elements
EP0171852A1 (en) * 1984-08-06 1986-02-19 Shell Internationale Research Maatschappij B.V. Rotary drill bit
US20040245840A1 (en) * 2002-09-12 2004-12-09 Tubergen Renard G. Seating with comfort surface
US7226130B2 (en) * 2002-09-12 2007-06-05 Steelcase Development Corporation Seating with comfort surface
US20060071522A1 (en) * 2003-06-05 2006-04-06 Steelcase Development Corporation Control for seating unit with back stop
US7568763B2 (en) 2003-06-05 2009-08-04 Steelcase Inc. Control for seating unit with back stop
US20100263875A1 (en) * 2009-04-15 2010-10-21 Williams Adam R Drilling systems for cleaning wellbores, bits for wellbore cleaning, methods of forming such bits, and methods of cleaning wellbores using such bits
US8887836B2 (en) * 2009-04-15 2014-11-18 Baker Hughes Incorporated Drilling systems for cleaning wellbores, bits for wellbore cleaning, methods of forming such bits, and methods of cleaning wellbores using such bits
US20150136493A1 (en) * 2013-11-20 2015-05-21 Longyear Tm, Inc. Drill Bits Having Blind-Hole Flushing And Systems For Using Same
US9506298B2 (en) * 2013-11-20 2016-11-29 Longyear Tm, Inc. Drill bits having blind-hole flushing and systems for using same

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