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Publication numberUS2994389 A
Publication typeGrant
Publication dateAug 1, 1961
Filing dateJun 7, 1957
Priority dateJun 7, 1957
Publication numberUS 2994389 A, US 2994389A, US-A-2994389, US2994389 A, US2994389A
InventorsBus Sr Franklin L Le
Original AssigneeLe Bus Royalty Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Combined drilling and reaming apparatus
US 2994389 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

Aug. 1, 1961 F. L. LE BUS, SR

COMBINED DRILLING AND REAMING APPARATUS 2 Sheets-Sheet 1 Filed June 7, 1957 NH" "Id-"I'l INVENTORQ F L. Le BU BY z fl c ATTORNEY 2 Sheets-Sheet 2 Aug. 1, 1961 F. L. LE BUS, SR

COMBINED DRILLING AND REAMING APPARATUS Filed June 7, 1957 E m5 ,2, m s A n 0 E U o o o 7 B llliLfiE. M I I I l l I l I I I I I I I l I l I I I l Ill-l n e L l. l L l E M H v: M w m m \w T 9 3 T L n A L b 9 JJJ H llllllll IL q flnll lu l l un lnl 1 ||||l.||||||ll.l. r

United States Patent 2,994,389 COMBINED DRILLING AND REAMWG APPARATUS Franklin L. Le Bus, Sr., Longview, Tex., assignor to Le Bus Royalty Company, Longview, Tex., a partnership Filed June 7, 1957, Ser. No. 664,205

- 4 Claims. (Cl. 175321) This invention relates to a combined reamer and drill bit apparatus for oil well bores and more particularly, but not by way of limitation, to an apparatus wherein the well bore may be first drilled and then reamed without pulling the tool from the well bore.

In the drilling of an oil well bore in certain types of areas, extreme incline and anticline formation conditions are often encountered. These subsurface conditions usually cause a great problem in the drilling of a well bore in that a considerable amount of key-seating occurs within the hole. It has been found that a simultaneous drilling and reaming of the hole through the key-seating area is not efficient or practical. It is usually desirable to drill a small hole through the key-seating area and then enlarge or ream the hole to the desired size. In order to accomplish this, the drill collars must be pulled after the forming of the small hole, and the reamer is then lowered into the bore for reaming the well bore. Furthermore, there are many subsurface formations that are extremely hard to drill through, such as chert and granite. Experience in the industry has shown that it is advantageous to drill a small hole through such hard formations, and then pull out the small bit in order to go back into the hole with a reamer or larger bit. It will be apparent that the time consumed during the pulling of the drill collars, and changing of tools not only delays the time of completion of the well bore, but also is a costly operation.

This invention contemplates a novel combination reamer and drill bit so designed and constructed to permit the drilling of a small hole through a subsurface formation and then reaming the hole to an enlarged size without the necessity of pulling the drill string from the well bore. When it is desired to continue the drilling operation with a simultaneous reaming and drilling action, the novel tool may be moved to a locked or drilling position for the combined operation. The drill bit may be utilized to drill downwardly through a key-seat area, after which the reamer portion may be operated to ream out the keyseats for an elimination thereof. The drill collar assembly which carries the drill bit functions as a guide for the reamer, thereby assuring an efiicient reaming of the hole therearound. The operation may be repeated as many times as necessary during the drilling of the well bore to eliminate the disadvantages of the key-seats. After the key-seat area has been drilled through, the tool may be locked whereby the reamer and drill bit will provide a simultaneous reaming and drilling of the bore. Thus, a small hole may be drilled and then enlarged to substantially any desired size in one trip of the tool into the well bore.

It is an object of this invention to provide a novel combined reamer and drill bit apparatus to provide a simultaneous reaming and drilling operationfor a well bore.

It is another object of this invention to provide a novel well drilling apparatus particularly designed and constructed to facilitate the drilling of a well bore through extremely hard subsurface formations as Well as facilitate the drilling of a well bore through incline and anticline subsurface conditions.

And still another object of this invention is to provide a novel tool for well bores wherein the bore may be drilled and reamed in separate and consecutive operations without removing the drill collars from the well bore.

ICC

An additional object of this invention is to provide a combined drilling and reaming apparatus for well bores which operates in separate and simultaneous operations in one trip of the apparatus into the well bore.

A further object of this invention is to provide a combined reamer and drill apparatus for a Well bore which is simple and efiicient in operation and economical and durable in construction.

- Other objects and advantages of the invention will be evident from the following detailed description, read in conjunction with the accompanying drawings, which illustrate my invention.

In the drawings:

FIGURE 1 is a broken elevational view partly in section of the upper portion of the novel tool in an open telescoped position for drilling.

FIGURE 1A is a view similar to FIG. 1 of the lower portion of the novel tool and having portions thereof shown dotted for clarity.

FIGURE 2 is a broken elevational view partly in section of the novel tool in a full closed position for a simultaneous drilling and reaming operation, and with certain portions shown dotted for clarity.

FIGURE 3 is a view similar to FIG. 2 depicting a modified form of the invention.

FIGURE 4 is a broken elevational view of the lower portion of a tool similar to that shown in FIG. 3 and depicting a core drill utilized therewith.

Referring to the drawings in detail, reference character it) refers in general to a combined reaming and drill tool comprising an outer jacket or sleeve unit 12 telescopically disposed over an inner mandrel 14. The sleeve unit 12 comprises an upper sub member 16 provided with a threaded portion 18 at the upper end thereof for connection with the lowermost end of the drill collar string 20, which is in turn suitably secured to the drill string (not shown) extending upwardly into the well bore. The upper sub or head member 16 extends downwardly into threaded connection at 22 with a tubular reamer having a plurality of like sections 24 having a suitable reamer shoe 26 secured at the lowermost end section thereof. A plurality of circumferentially spaced lug members 28, preferably two diametrically opposed (but not limited thereto), are provided on the inner periphery of the tubular body member 24 for a purpose as will be hereinafter set forth.

The inner mandrel 14 comprises tubular female spline body 36 extending downwardly into threaded connection at 32 with a string of drill collars 34. The drill collars 34 are threadedly connected at 36 to a lower female spline body 3 8 having a suitable drill bit 40 secured to the lower end thereof in any well known manher (not shown). The upper female spline body 30 is provided with a plurality of circumferentially spaced female spline or recessed portions 42, preferably two diametrically opposed for cooperation with the lug members 23, as will be hereinafter set forth. Each of the recesses 42 comprises a vertical slot 44 having the lower end thereof open to receive one of the lug members 28 therein. A second vertical groove or slot 46 is provided for each of the female splines 42 and is connected with the first vertical groove 44 by a substantially horizontal groove 48. The groove 46 is closed at its upper end by a shoulder 45 and at its lower end by a shoulder 47. The lower portion of the second groove 46 is separated from the first groove 44 by a vertical shoulder portion 50 for a purpose as will be hereinafter set forth.

A helical or spiral shoulder 52 is provided at the top of the vertical groove 44 and extends to the groove 46 for facilitating moving the lug 28 from the groove 44 into the groove 46 upon an upward movement of the outer sleeve '24 with respect to the inner mandrel 14. A

tapered edge portion 54 is provided on the lower portion of the lug 28 for facilitating moving of the lug 28 from the groove 46 into the groove 44 upon a downward movement of the outer sleeve 24 with respect to the mandrel 14. A tapered shoulder portion 56 is provided on the lower edge of the female spline body 30 and is in communication with the open end of the vertical groove 44 for automatically directing the lugs 28 into the groove 44 upon an upward movement of the outer sleeve 24 with respect to the mandrel 14. A vertical groove or passageway 58 extends downwardly from the top of the female spline body 30 into communication with the female spline 42 to provide a fluid passageway for circulation of fluid downwardly between the body 30 and the sleeve 24 to assure an adequate fluid circulation around the reamer shoe 26 during the reaming operation.

The lower female spline body 38 is preferably of a slightly larger outer diameter than the drill collars 34 to provide a circumferential shoulder 69 at the top thereof. A plurality of oircumferentially spaced vertical grooves 62, preferably two diametrically spaced, extend longitudinally downward from the shoulder 60 to receive the lug member 28 when the outer sleeve 24 is in a lowered position with respect to the mandrel 14, as shown in FIG. 2. The lowermost end of the grooves 62 is closed by a shoulder 63. A spiral or helical shoulder portion 64 is provided on the shoulder 69 and in communication with each of the vertical grooves 62 for facilitating the disposition of the lug members 28 within the grooves 62 during a downward movement of the sleeve 24 over the lower spline body 38.

Operation The combined reamer and drill tool ltt in assembled relation may be lowered into the well bore in a locked position when it is desired to begin the drilling and reaming operation. In order to lock the assembly, the outer jacket 12 is raised vertically with respect to the inner mandrel 14. The lug members 28 are automatically moved into the vertical grooves 44 upon contact with the tapered shoulders 56 during the upward movement of the jacket 12. A continued upward movement of the jacket 12 will bring the lugs 28 into contact with the spiral shoulder 52 whereupon the lugs will be automatically directed into the vertical groove 46 and adjacent the upper shoulder 45 thereof. In this position (not shown), the inner spline body 30 will hang on the lugs 28, thereby supporting the inner mandrel 14 within the outer jacket unit 12 during the lowering of the unit into the well bore. It will be apparent that the combined unit 10 is in a full telescopically extended position as the unit is lowered into the well bore.

When it is desired to drill a small or pilot hole ahead of the reaming of the hole, such as in a hard formation, or through a key-seating type of formation, the outer jacket 12 is lowered slightly over the spline body 36 to move the lugs 23 into the lower portion of the groove 46 and adjacent the lower shoulder 4'7, as shown in FIG. 1A. The tool 10 is still in an extended position with the reamer head 26 disposed above the drill bit 40 within the well bore. The weight of the jacket 12 and the drill string thereabove is transmitted to the mandrel 14 and the drill bit 40 through the contact of the lugs 28 adjacent the lower shoulder 47 of the groove 46. Clockwise rotation of the outer jacket unit 12 will move the lugs 28 against the vertical shoulder 50, thereby transmitting the rotation of the jacket 12 to the mandrel 14 and the drill bit 40 carried thereby. In this manner, the well bore may be drilled in the usual manner well known in the industry.

Drilling fluid circulating through the drill string will flow downwardly through the reamer sleeve 24 and through the drill collars 34 to the bit 40 for assuring an adequate fluid circulation during the drilling operation.

The drilling of the well bore may be continued with the unit 10 in the extended position as long as desired.

When it is desired to enlarge or ream the well bore, the outer jacket 12 may be raised slightly with respect to the female spline body 30 with a simultaneous clockwise rotation thereof. As the lugs 28 are moved upwardly within the groove 46 and out of contact with the vertical shoulder 50, the tapered portion 54 of the lugs 28 will be moved across the shoulder 56 for directing the lugs 28 into the grooves 44. In this position, a downward movement of the outer jacket 12 will move the lugs 28 out of the grooves 44 and free the outer jacket 12 from engagement with the mandrel 14. In the released position, the outer jackets 12 and 24 may be rotated independently of the inner mandrel to ream the bore as the outer jacket moves downwardly over the mandrel. The drill collars 34 will function to guide the downward movement of the reamer to assure an eflicient reaming of the bore.

A portion of the drilling fluid circulating downwardly through the drill string will be directed downwardly through the fluid passageways 58 and through the groove 44 to the reamer shoe 26 to assure an efiicient and adequate fluid circulation to the reamer shoe 26 during the reaming operation.

The downward movement of the outer jacket 12 with respect to the inner mandrel 14 is limited by the contact of the lugs 28 with the lower end or shoulder 63 of the vertical grooves 62 in the lower spline body 38. As the outer jacket moves downwardly over the mandrel, the lugs 28 are brought into contact with the shoulder 60 and the spiral portions 64 thereof. The spiral portions 64 will automatically direct the lugs 28 into disposition Within the groove 62 for limiting the downward movement of the jacket 12, as shown in FIG. 2.

In this fully lowered position of the outer jacket 12 with respect to the inner mandrel 14, the drilling and reaming operation may be continued simultaneously. The contact between the lugs 28 and the vertical side Walls of the grooves 62 will transmit the rotation of the outer jacket to the lower female spline body 38 and the drill bit 40 connected thereto. The contact of the lugs 28 with the bottom of the groove 62 will transmit the weight of the jacket 12 and the drill string thereabove to the bit 40 to permit a continued simultaneous drilling and reaming operation.

It will be apparent that the telescopic arrangement of the outer jacket 12 with respect to the inner mandrel 14 Will also permit the insertion of additional sections of pipe in the drill string without raising the drill bit from the bottom of the well bore. When it is necessary to add a pipe section to the drill string for continuing the drilling operation, the outer jacket 12 may be raised over the inner mandrel 14, as hereinbefore set forth, without raising the mandrel 14 or drill bit 40 from the bottom of the well bore. The pipe section may then be inserted in the drill string, and the reaming and drilling operation may be continued as hereinbefore set forth, either simultaneously or separated as desired.

FIGURE 3 depicts a modification of the novel tool 10 wherein the lower spline body 38 is eliminated. The drill bit 40 is connected directly to the drill collars 34 in any Well known manner. In this form of the invention, the drilling and reaming are usually done in separate operations. The drilling operation may be accomplished with the tool 10 in the extended position, and the reaming may be done independently of the drilling operation by releasing the connection between the outer jacket 12 and inner mandrel 14, as hereinbefore set forth. However, it will be apparent that there is no connection between the inner mandrel 14 and the outer jacket 12 in the lower portion for the jacket. Thus, further drilling of the well bore is only possible when the outer jacket 12 is raised over the mandrel 14 to position the lugs 28 Within the female splines 42 and in the drilling position therein. The downward movement of the jacket 12 over the mandrel 14 is limited by the contact of the lower edge or shoulder 66 of the upper sub 16 against the upper edge or shoulder 68 of the female spline body 30, as shown in FIG. 3.

FIGURE 4 depicts still another modification of the tool wherein a suitable core barrel 70 having a core drill 72 carried at the lower end thereof is utilized in lieu of the drill collars 34 and drill bit 40 which are shown in FIG. 3. The core drilling and reaming operations are usually done separate in a manner similar to that set forth in the modification shown in FIG. 3. There is no connection between the jacket unit 12 and the core barrel 70 in the substantially lowered position for the jacket 12, as shown in FIG. 4. Thus, the coring unit may be operated only when the jacket 12 is in the extended drilling position as hereinbefore set forth.

From the foregoing, it will be apparent that the present invention provides a novel combined reaming and drilling tool for oil well bores wherein the drilling and reaming may be done either separately or simultaneously without raising the drill bit from the bore or changing tools. The novel tool is of particular advantage in the drilling of well bores through hard subsurface formations, or through incline and anticline formations wherein keyseating of the well bore is frequently encountered. The novel tool also permits the insertion of additional pipe sections in the drill string without raising the drill bit from the bottom of the bore, thereby greatly facilitating the drilling of the well bore. The combined reaming and drilling apparatus is simple and efficient in operation and economical and durable in construction.

Changes may be made in the combination and arrangement of parts as heretofore set forth in the specification and shown in the drawings, it being understood that any modification in the precise embodiment of the invention may be made within the scope of the following claims without departing from the spirit of the invention.

I claim:

1. A combined reaming and drilling apparatus for well bores comprising an inner tubular mandrel member, a reamer drive sleeve telescopically disposed over the mandrel, drill means carried by the mandrel, reamer means carried by the reamer drive sleeve, said mandrel member comprising an upper female spline body and a lower female spline body, lug means provided on the inner periphery of the reamer sleeve for cooperation with the upper spline for locking the mandrel and sleeve member in an extended position for simultaneous movement therebetween for drilling the well bore before reaming thereof, said lug means cooperating with the lower spline body for locking the mandrel and drive sleeve member in a lowered position for the drive sleeve to provide a simultaneous movement therebetween for simultaneously reaming and drilling the well bore, said lug means adapted for disposition between the spline bodies to disconnect the sleeve member from the mandrel to permit rotation of the sleeve member independently from the mandrel for reaming of the well bore without a drilling thereof.

2. A combined reaming and drilling apparatus for well bores, and comprising a mandrel member, a reamer drive sleeve member telescopically disposed over the mandrel member, said mandrel comprising a plurality of drill collar members connected together in tandem relation, a drill bit carried at the lower end of the drill collars, a female spline body carried at the upper end of the drill collars, male spline members provided on the inner periphery of the sleeve drive member for cooperation with the female spline members, said male spline members in one position with respect to the female spline members providing for a locking engagement between the sleeve member and mandrel to permit a simultaneous movement thereof in a raised position of the sleeve member, said male spline members in another position with respect to the female spline members providing for a disengagement of the sleeve member from the mandrel to permit simultaneous rotation and downward movement of the drive sleeve member with respect to the mandrel for an independent reaming of the well bore, and fluid passageway means provided between the drive sleeve and mandrel members for fluid circulation through the apparatus during the drilling and reaming operation.

3. In a combined reaming and drilling apparatus for a wellbore, and outer tubular housing member telescopically disposed over an inner tubular mandrel member, a reamer shoe carried by the outer housing member, a drill bit carried by the mandrel member, a plurality of circumferentially spaced lug members provided on the inner periphery of the outer housing member, a plurality of circumferentially spaced upper female spline members provided on the mandrel member and having at least one open end for receiving the lug members, said lug members and female spline members cooperating in one position to provide for a simultaneous movement between the outer housing and the mandrel member, said open end of the female spline members permitting disengagement of the lug members upon a downward movement of the outer housing with respect to the mandrel whereby the outer housing may be rotated with respect thereto for an independent reaming of the well bore, a plurality of circumferentially spaced lower groove members provided on the mandrel for receiving the lug members upon a lowered position of the outer housing member, spiral shoulder means provided adjacent the lower grooves for automatically directing the lugs into the lower grooves, said lugs and lower grooves cooperating to provide for simultaneous movement between the outer housing and mandrel member for a simultaneous reaming and drilling operation, and fluid passageway means for fluid circulation through the apparatus during the reaming and drilling operation.

4. In a combined reaming and drilling apparatus for a well bore, an outer jacket drive member telescopically disposed over an inner mandrel member, reaming means carried by the outer jacket, drilling means carried by the mandrel member, male spline means provided on the inner periphery of the outer jacket, upper female spline means provided on the mandrel for cooperation with the male splines in a raised position of the outer jacket member to provide for simultaneous movement between the jacket and mandrel members in an extended position therebetween for drilling the well bore before a reaming thereof, lower female spline means provided on the mandrel for cooperation with the male splines in a lowered position of the outer jacket drive member to provide for simultaneous movement between the jacket and mandrel means in a closed position therebetween for a combined reaming and drilling of the well bore, said outer jacket drive member adapted for disengagement from the inner mandrel when the male spline members are positioned between the upper and lower female splines to permit rotation of the outer jacket and simultaneous movement downward with respect to the mandrel for an independent reaming of the well bore.

References Cited in the file of this patent UNITED STATES PATENTS Re. 20,405 Stroud June 8, 1937 1,391,626 Gilthorpe Sept. 20, 1921 1,449,533 Moore Mar. 27, 1923 1,909,187 Oskenholt May 16, 1933 2,212,067 Hotfoss Aug. 20, 1940 2,309,866 Reed 'Feb. 2, 1943 2,776,817 Gregory et al Ian. 8, 1957 2,815,930 Storm Dec. 10, 1957

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Referenced by
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US3131778 *Dec 11, 1961May 5, 1964Emerson William CDrilling deflection apparatus
US3151690 *Mar 17, 1961Oct 6, 1964Gas Drilling Service CoWell drilling apparatus
US5735359 *Jun 10, 1996Apr 7, 1998Weatherford/Lamb, Inc.Wellbore cutting tool
US6484820 *Nov 25, 1997Nov 26, 2002Wirth Maschinen-Und Bohrgeraete Fabrik GmbhMethod and device for driving bore-holes, especially in the sea bed, using a guide tip
US8056651 *Nov 15, 2011Baker Hughes IncorporatedAdaptive control concept for hybrid PDC/roller cone bits
US8141664Mar 27, 2012Baker Hughes IncorporatedHybrid drill bit with high bearing pin angles
US8157026Apr 17, 2012Baker Hughes IncorporatedHybrid bit with variable exposure
US8191635Oct 6, 2009Jun 5, 2012Baker Hughes IncorporatedHole opener with hybrid reaming section
US8336646Dec 25, 2012Baker Hughes IncorporatedHybrid bit with variable exposure
US8347989Jan 8, 2013Baker Hughes IncorporatedHole opener with hybrid reaming section and method of making
US8356398Jan 22, 2013Baker Hughes IncorporatedModular hybrid drill bit
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US8910729 *Apr 14, 2010Dec 16, 2014Core Geotechnics Co., Ltd.Method and apparatus for drilling large-diameter hole in ground
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US20110079440 *Apr 7, 2011Baker Hughes IncorporatedHole opener with hybrid reaming section
US20110079441 *Apr 7, 2011Baker Hughes IncorporatedHole opener with hybrid reaming section
US20110079442 *Oct 6, 2009Apr 7, 2011Baker Hughes IncorporatedHole opener with hybrid reaming section
US20110079443 *Apr 7, 2011Baker Hughes IncorporatedHole opener with hybrid reaming section
US20110079444 *Apr 7, 2011Baker Hughes IncorporatedExternal, Divorced PDC Bearing Assemblies for Hybrid Drill Bits
US20110120269 *May 26, 2011Baker Hughes IncorporatedModular hybrid drill bit
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Classifications
U.S. Classification175/321, 175/381
International ClassificationE21B10/26
Cooperative ClassificationE21B10/26
European ClassificationE21B10/26