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Publication numberUS3352370 A
Publication typeGrant
Publication dateNov 14, 1967
Filing dateAug 31, 1964
Priority dateAug 31, 1964
Publication numberUS 3352370 A, US 3352370A, US-A-3352370, US3352370 A, US3352370A
InventorsLivingston Herman G
Original AssigneeLivingston Herman G
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Directional drilling tool
US 3352370 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

14, 1967 H. c;v LIVINGSTON 3,352,370

DIRECTIONAL DRILLING TOOL Filed Aug. 31, 1964 2 Sheets-Sheet 1 Her/r700 6T l/wxzyuzan INVENTOR.

ATTOF/VfVJ Nov. 14, 1967 H. G. LIVINGSTON DIRECTIONAL DRILLING TOOL Filed Aug. 31, 1964 2 Sheets-Sheet .2

He r0700 6. Z /l///7 9'J fan INVENTOR.

A ITO/P/VE VJ United States Patent 3,352,370 DIRECTIONAL DRILLING TOOL Herman G. Livingston, P.O. Box 1040, Liberty, Tex. 77575 Filed Aug. 31, 1964, Ser. No. 393,095 Claims. (Cl. 175-73) This invention relates to new and useful improvements in directional drilling tools and more particularly to a tool for altering the bearing of an inclined well bore.

Various devices have been provided in the past for changing the hearing or direction of a well as it is being dug with rotary drilling equipment. However, such devices require precise orientation either from the surface or at the bottom of the well which, in many instances, may be two miles or more beneath the earths surface, in order to direct the well on the desired deviational course. With the directional drilling tools which require orientation, it is frequently necessary to start the deviated portion of the well over two or three or more times in order to direct the deviated portion of the well in the desired direction. Another disadvantage of the prior art directional tools is that such tools are generally capable of drilling only relatively short distances without having to be withdrawn from the hole or well and replaced with conventional drilling apparatus. Thus, the use of such directional tools, which have heretofore been available, requires that the drilling operations be interrupted once, while the drill string is withdrawn and the normal drilling tools replaced with the directional drilling tool and then, after drilling only a relatively short distance, the drilling operation must again be interrupted while the directional tool is withdrawn from the well and replaced with the ordinary or conventional drilling tool. Thus, it can be appreciated that the cumbersome procedures required with such tools detract greatly from their usefulness.

Therefore, an object of the present invention is to provide a new and improved directional drilling tool for altering the bearing or direction of an inclined well bore which orients itself relative to the well bore.

Another object of the present invention is to provide a new and improved directional drilling tool for resisting a change of direction of a Well bore drilled with rotary drilling equipment.

A further object of the present invention is to provide a new and improved directional drilling apparatus adapted to minimize the number of whipstocks or knuckle joints required in an off-vertical well.

And yet another object of the present invention is to provide a new and improved directional drilling tool for altering the direction of a well which is capable of drilling relatively large distances without requiring removal from the hole or well.

A further object of the present invention is to provide a new and improved directional drilling apparatus for gradually changing the direction or drift of a well being drilled with rotary drilling equipment.

And yet another object of the present invention is to provide a new and improved apparatus for altering the direction of an inclined well bore including an eccentric projection rotatably carried on a drill collar to change the attitude of the drill bit with respect to the axis of the hole.

Another object of the present invention is to provide a new and improved directional drilling apparatus for use With conventional directional drilling devices such as whipstocks and knuckle joints for directing the well bore in a desired direction.

And yet another object of the present invention is to provide a new and improved directional drilling apparatus for altering the direction of an inclined well bore which includes a drill collar string having a longitudinal fluid passage therethrough, 'a sleeve rotatably mounted on said drill collars and having a lateral projection or eccentric formed thereon with a fluid port in said eccentric projection communicating the fluid passage of said drill collar string for discharging fluid in a lateral direction with respect to said drill collar string for urging the drill collars laterally with respect to the axis of the well bore.

And still another object of the present invention is to provide a new and improved directional drilling tool including a drill collar string, a hollow mandrel rotatably mounted on said drill collar string with an eccentric projection on said hollow mandrel for engaging the well bore to displace the drill collars thereof laterally with respect to the axis of the well and having friction means disposed between said drill collar string and said hollow mandrel for urging the mandrel and the eccentric projection to partially rotate with the drill collar string.

And yet a further object of the present invention is to provide a new and improved directional drilling apparatus for use with conventional directional drilling devices such as whipstocks and knuckle joints and the like for maintaining the deviated well in a desired direction.

Other and further objects and advantages of the invention will become more apparent from a consideration of the following description and drawings wherein:

FIG. 1 is a vertical sectional view of an inclined well bore having a rotary drill string disposed therein with the apparatus of this invention carried thereon:

FIG. 2 is an enlarged vertical sectional view after the device of the present invention has been actuated and showing details of construction of the apparatus of the present invention;

FIG. 3 is a sectional view taken on lines 3-3 of FIG. 2 showing further details of construction of the directional drilling tool of the present invention;

FIG. 4 is a vertical sectional view of an inclined well bore showing a rotary drill string disposed therein with directional drilling apparatus of this invention positioned at spaced intervals thereon prior to actuation, and

FIG. 5 is a sectional View showing details of construction of one form of the apparatus of the present invention after it has been actuated.

In FIG. 1 of the drawings, an inclined well bore 4 is shown with a drill collar string 6 supported therein on a drill string 7 which extends upwardly to the earths surface where it is connected to rotary drilling equipment (not shown) which is provided for rotating the drill string 7 and the drill collars 6 in the well 4. The drill collar string 6, which has a drill bit 8 aifixed to its lower end for cutting or digging the well bore 4, also carries the directional drilling device of the present invention, designated generally at 9, which directs the course of the drill bit 8, as will be explained in detail hereinafter. Due to the inclination of the well bore 4 the force of gravity causes the drill collars 6 and the device 9 carried thereon to normally engage the lower side 4a of the Well bore for a purpose to be described herein.

Briefly, the apparatus 9 comprises a sleeve or tubular member 10 having an eccentric 11 thereon and torque transmitting means designated generally 12 therewith, for transmitting torque from the drill collar 6 to rotate the sleeve 10. When the sleeve 10 is rotated the projection 11 is forced against the inner surface of the well bore, and the force of reaction forces the drill collars 6 from the position they normally occupy to change the attitude of the drill bit 8 on the bottom of the Well bore and thereby change the direction of the well bore 4, as will be explained in detail herein.

3 V It can be appreciated that when a well has a tendency to drift or change direction, the apparatus of the present invention can be used to counteract the forces which tend to change the direction or course of the well and thus the presentinvention is equally useful for changing the direction of a well and also for negating such change. Also, it should be noted that the directional drilling apparatus of the present invention will not necessarily elimi- 'nate whipstocks or knuckle-joints or other conventional directional drilling tools but rather can be used in conjunction with such tools. However, in many instances, the use of the apparatus of the present invention will reduce or minimize the number of conventional directional drilling tools required.

Considering the apparatus 9 of the present invention in more detail, as seen in FIG. 2 of the drawings, the drill collar 6a is reduced in its diameter along its longitudinal axis at 16 to provide a longitudinally and circumferentially extending recess for receiving the hollow sleeve 'or hollow mandrel 10. Such reduced diameter portion 16 is preferably formed at the lower end of the drill collar 6a and thus provides access to the sleeve 10 by simply disconnecting the adjacent drill collar 6b which is normally connected to the drill collar 6a by a threaded pin and box connection designated at 20. This greatly facilitates the installation or removal of the sleeve 10 in the event it becomes necessary to repair the tool or to replace the sleeve 10 with one having a diiferent size eccentric 11.

The reduced diameter portion 16 forms an annular shoulder 17 in the drill collar 6a for preventing upward longitudinal movement of the sleeve 10 relative to the drill collar 6a. Also, it will be noted that the upper end 18 of the adjacent drill collar 6b provides an annular surface for engaging the lower end of the sleeve 10 to prevent its longitudinal movement downwardly relative to the drill collar 6a.

, The reduced diameter portion 16 has one or more radially extending ports or passages 22 formed therein which are in communication with a fluid passage 60 which extends longitudinally through the drill collar string 6 and the drill stem 7 for conducting drilling fluid to the drill bit 8 in a manner well known in the art. One or more of such fluid passages 22 are provided for conducting fluidfrom the longitudinal fluid conduit 6c to one or more ports or openings 15 in the eccentric 11, for a purpose to be explained hereinafter. Also, a plurality of longitudinally and circumferentially spaced bearing, seats or recesses 25 are formed in the outer surface of the reduced diameter portion 16 for receiving suitable bearings 25a which are provided to facilitate the rotation of the sleeve 10 and the drill collar 6b relative to each other. Passages 25b are provided in the sleeve 10 for positioning the ball bearings 25a in thebearing seats 25. It can be appreciated that other suitable anti-friction means may be disposed between the sleeve 10 and the drill collar 60 to facilitate the rotation of each with respect to the other, as desired.

' The hollow sleeve or tubular body 10 has a passage or bore lfla extending longitudinally therethrough which is of slightly larger diameter than the reduced diameter portion 16 which it surrounds. An internal annular groove or counterbore 30' is preferably formed in the sleeve 10 which provides a circumferentially extending race for receiving a plurality of radially or outwardly expanding springmeans 33 which function as a drive means for transmitting torque from the drill collar 6a to the sleeve or tubular member 10. Such springs 33 are shown as being leaf type springs and are connected to the drill collar 6a by means ffpins'3 3a or other suitable connecting means, as desired, It will be appreciated that other suitable torque transmitting means may be provided on the drill collar 64 'or the sleeve for transmitting torque therebetween without departing from the scope of the present invention. Also, while three springs 33 are shown as being used to transmit torque from the drill collar 6a to the sleeve 10,

it is understood that any suitable number may be used without departing from the scope of the present invention.

As best seen in FIG. 3 of the drawings, the race or annular groove 30 in the sleeve 10 has a cam surface 11a provided therein adjacent the eccentric projection 11, which cam surface 11 ais engaged or struck intermittently by the springs 33. as they are rotated by the drill collar 61: to intermittently increase the frictional drag of the springs 33 on the sleeve 10. The sleeve 10 also has an internal annular groove 35 formed therein which communicates with the passage 15 in the eccentric 11 and which is aligned to communicate with the radial passage or bore 22 in the drill collar 6a for conducting fluid from the longitudinal fluid conduit 6c to the port 15 from which such fluid is discharged in a high velocity stream onto the inner surface of the well bore 4 so that the force of reaction of the stream of fluid ejected from the eccentric 11 will serve to urge the eccentric projection 11 into engagement with the inner surface of the well bore 4 and also tend to move the drill collars out of alignment with the well bore 4. As best seen in FIG. 3 of the drawings, the port 15 is aligned to discharge fluid from the rear or trailing side of the projection 11 as it is rotated clockwise and in the event the sleeve 10 were used with a counterclockwise rotating drill collar, the direction of the port 15 could be reversed so that fluid discharged therefrom would urge the sleeve 10 to rotate in the same direction as the drill collar on which the sleeve is carried.

Suitable seal means, such as O-rings or the like which are shown at 36, are provided between the sleeve 10 and the drill collar 6a on the upper and lower sides of the annular groove 35 to seal against leakage of fluid from the groove 35.

From the foregoing description it can be appreciated that the present invention provides a tool for gradually altering the course of an inclined well bore or for mini mizing the alteration of direction of an inclined well bore, wherein an eccentric projection 11 is provided on a sleeve 10 which is rotatably mounted on a drill collar 6a and wherein friction means 33 are disposed between the drill collar 6a and the sleeve 10 for transmitting torque from the drill collar to the sleeve to urge the pro jection 11 into engagement with the inner surface of the well bore to thereby displace the drill collar 6 relative to its normal position in the well bore 4 and thus deviate the course of the well from the path it would normally follow.

It can be appreciated that the weight of the drill collar 6 against the lower side 4a of the inclined well bore 4 will create a bearing force which opposes the tendency of the sleeve 10 and the eccentric 11 to rotate with the drill collar string 6. The friction drive means or springs 33 are provided for partially overcoming such bearing force caused by the weight of the drill collar string 6 against the lower surface 4a to lift or displace such drill collar string from the position which it would normally occupy if controlled only by the weight of gravity. Thus, it will be evident that in different situations ditterent size projections will be desirable. The radial distance'by which the eccentric 11 projects from the axis of the drill collars will depend in part on the diameter of the well bore 4, the number of drill collars used in the drill collar string, and other factors. Also, it will be appreciated that the frictional force exerted by the springs or other torque transmitting means 33 may also be varied, depending upon the characteristics of a particular well bore.

in describing theme of the directional tool 9 of the present invention, it will be assumed that the drill collars in the drill collar string are being rotated in a clockwise direction as viewed in FIG 3 of the drawings. However, it will be understood that the device 9 may also be used when the drill collars and the sleeve 10 carried thereon are rotated in a counterclockwise direction.

As previously noted herein, the force of gravity urges the drill collars 6 into engagement with the lower side 4a of the well bore 4 so that when the drill collar 6a is rotated, the bearing force of the drill collars 6 creates a frictional drag on the sleeve 10 which tends to prevent its rotating with the drill collars 6. However, the same rotation causes the spring 33 attached to the drill collar 6a to exert a frictional drag on the race 30 to urge the sleeve 10 and the eccentric 11 to rotate'with the drill collars 6. As such springs 33 rotate in the race 30 they produce a slightly greater frictional drag than is caused by the engagement of sleeve 10 with the bore 4 and thus force the projection 11 into engagement with the inner well wall 4a to displace the drill collars 6a relative to their normal positions in the well bore.

In addition to the general frictional drag of the springs 33 in the race 30, the springs 33 intermittently strike the cam surface 11a provided adjacent the eccentric 11 to impart a further force to the eccentric 11 which is engaging the inner surface of the well bore 4 (FIG. 3) thereby applying an additional opposing or resultant force on the drill collars 6. In addition to the frictional force which is provided for urging the sleeve 10 to rotate with the drill collars 6, drilling fluid from the drill string 7 and the drill collar string 6 is ejected in a constant high velocity stream from the port or passage 15 in the rearward side or trailing side of the eccentric projection 11 onto the surface of the well bore 4 to add an additional force to those already urging the eccentric into engagement with the inner surface of the well bore 4 to displace the drill collars 6 from their normal position in the bore 4. It will be appreciated that in some instances the port 15 may be closed and the device 9 operated without the fluid jet stream, and in other instances, additional ports may be added to discharge fluid from the eccentric Without departing from the scope of the present invention.

It should be noted that when the apparatus or tool 9 is positioned on the drill collar string 6 near the bit 8, such drill collar 6 is normally urged to the left side of the well bore 4 with the apparatus 9 as viewed in FIG. 3, to thus cause the well bore 4 to drift gradually to the left as the drilling continues. However, the bit 8 may be caused to drift to the right as viewed in FIG. 3 by changing the distance of the tool or apparatus 9 from a position adjacent the bit 8 at the lower end of the drill collar string 6 to a position more remote from the bit 8, such as forty or fifty or sixty feet up the drill collar string 6 from the bit 8. In both instances it is assumed the drill string 6 is being rotated clockwise as viewed in FIG. 3 and it is understood that in each instance the device or tool 9 and the portion of the drill collar adjacent thereto is displaced to the right or in a clockwise direction relative to the bore 4 as viewed in FIG. 3; however, when the apparatus 9 is positioned remotely relative to the bit 8, the bit will be caused to drift to the left to gradually deviate or alter the direction of the well as the drilling proceeds. Also, as noted heretofore, the device 9 can be used to negate drift in the direction of the well 4, when desired.

As best seen in FIG. 4 of the drawings, a plurality of the drilling tools 9 of the present invention can be used simultaneously in the drill collar string 6 to stabilize the direction of the -well bore or to hold the well bore in a desired direction once such deviated direction has been attained by use of conventional directional tools. It will be appreciated that when a plurality of tools 9 are used simultaneously, such tools may be spaced at desired longitudinal distances relative to each other, or such tools may be closely grouped adjacent one another to cause the direction of the well to deviate or to prevent such deviation, as desired. Also, it will be appreciated that in some instances Where a plurality of the tools 9 is being used or when only a single tool 9 is used, it may be desirable to rotate the mandrel 10 in a direction opposite to the direction of rotation of the drill collars 6 on which the mandrel 10 is carried. In these instances, the springs or frictional drag means 33 may be omitted and the passage 15 (FIG. positioned so as to discharge drilling fluid in a direction which will urge the mandrel 10 to rotate in a direction opposite to the direction of rotation of the drill collars 6. In the FIG. 5 embodiment the drill collars 6 are rotated in the direction indicated by the arrow 39 and the mandrel 10 is urged in the direction of the arrow 38. Thus, when a plurality of tools 9 is used simultaneously, the direction of discharge of the drilling fluid from the port or passage 15 in each tool 9 can be arranged independently of the other tools 9, as desired, for stabilizing or controlling the direction of a deviated well bore.

Broadly, the present invention relates to a directional drilling apparatus for gradually deviating the course of an inclined well or hole or for negating such deviation, as desired.

What is claimed is:

1. A directional drilling device for automatically altering the, direction of an inclined well bore including,

(a) a rotatable drill string having a fluid passage extending longitudinally therethrough and having a drilling bit aflixed to the lower end thereof,

(b) a hollow mandrel rotatably mounted on said rotatable drill stem,

(c) a projection on said hollow mandrel,

(d) fluid discharge vent means in said projection at an angle relative to said mandrel,

(e) fluid passage means in said hollow mandrel communicating with said fluid discharge vent means, and

(f) fluid conduit means in said drill string connecting said longitudinal fluid passage therein for conducting fluid through said fluid discharge vent means to be discharged therefrom at an angle relative to said mandrel whereby said projection is urged to engagement with the inner wall of the well bore and thereby urges said drill string and drilling bit laterally to change the direction of the inclined well bore.

2. A directional drilling device for automatically altering the direction of an inclined well bore, including,

(a) drill collar means having a drilling bit aflixed to the lower end thereof and a longitudinally extending fluid therein for conducting fluid to said drilling bit,

(b) a hollow sleeve having a passage extending longitudinally therethrough for receiving said drill collar means and a projection on the outer surface thereof for engaging the inner surface of the inclined well bore,

(c) torque transmitting means disposed between said drill collar and said hollow sleeve for transmitting torque from said drill collar means to said hollow sleeve,

(d) fluid discharge port means through said projection at an angle relative to said sleeve, and

(e) fluid passage means communicating with said fluid conduit means in said drill collar means for conducting fluid to said fluid discharge port means through said projection whereby fluid is jetted therefrom and at an angle relative to said sleeve and onto the inner surface of the well bore to urge said eccentric projection into engagement with the inner surface of the well bore to laterally displace said drill collar means to change the direction of the inclined well bore.

3. A directional drilling device for automatically altering the direction of an inclined well bore, including,

(a) drill collar means having a drilling bit aflixed to the lower end thereof and a longitudinally extending fluid conduit therein for conducting fluid to said drilling bit,

(b) a hollow sleeve having a passage extending longitudinally therethrough for receiving said drill collar means and a projection thereon for engaging the inner surface of the inclined well bore,

(c) spring means disposed between said drill collar means and said hollow sleeve for urging said sleeve to rotate in the same direction with said drill collar means,

(d) fluid discharge port means through said projection at an angle relative to said sleeve, and I (e) fluid passage means communicating with said fluid conduit means and drilling bit in said drill collar means for conducting fluid to said fluid discharge port means through said projection whereby fluid is jetted therefrom and at an angle relative to said sleeve and onto the inner surface of the well bore to urge said eccentric projection into engagement with the inner surface of the well bore and to add by jet action additional thrust to laterally displace said drill collar means and drilling bit to change the direction of the inclined well bore.

4. A directional drilling device for automatically altering the direction of an inclined well bore, including,

(a) drill collar means having a drilling bit affixed to the lower end thereof and a longitudinally extending fluid conduit therein for conducting fluid to said drilling bit,

(b) a hollow sleeve having a passage extending longitudinally therethrough for receiving said drill collar and a projection thereon for engaging the inner surface of the inclined well bore,

(c) spring means disposed between said drill collar and said hollow sleeve for urging said sleeve to rotate in the same direction with said drill collar means,

(d) fluid discharge port means through the trailing side of said projection, and

5. A directional drilling device for altering the direction of an inclined well bore, including,

(a) drill collar means having a drilling bit 'aflixed to the lower end thereof and a longitudinally extending fluid conduit therein for conducting fluid to said drilling bit,

(b) a hollow sleeve having a passage extending longitudinally therethrough for receiving said drill collar means,

(c) a projection on said hollow sleeve for engaging the inner surface of the inclined well bore,

(d) fluid discharge port means in the said projection,

(e) said fluid discharge port means being in the leading side of said projection, and

(f) fluid passage means communicating with said fluid conduit means in said drill collar for conducting fluid to said fluid discharge port means in the leading side of said projection whereby fluid is jetted from said eccentric projection to urge said eccentric projection in a direction opposite to the direction of rotation of said drill collar means and into engagement with the inner surface of the well bore to laterally displace said drill collar and drilling bit to change the direction of the inclined well bore.

References Cited UNITED STATES PATENTS (e) fluid passage means communicating with said fluid 2 ghonasson i conduit means in said drill collar for conducting 2624409 1/1953 3f 166223 X fluid to said fluid discharge port means through the 2712434 7/1955 e 5 E 73 trailing side of said projection whereby fluid is dis- 2745635 4/1956 e a 175-776 charged onto the inner surface of the well bore to 3154156 10/1964 g 74 "7 urge said projection into engagement with the inner surface of the well bore and to add by jet action additional thrust to laterally displace said drill collar means and drilling bit to change the direction of the inclined well bore.

CHARLES E. 'OCONNELL, Primary Examiner.

JACOB L. NACKENOFF, Examiner.

IAN A. CALVERT, Assistant Examiner.

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3799279 *Sep 25, 1972Mar 26, 1974Farris ROptionally stabilized drilling tool
US3880246 *Dec 3, 1973Apr 29, 1975Farris Ralph JOptionally stabilized drilling tool, and method of use
US4076084 *Jul 16, 1973Feb 28, 1978Amoco Production CompanyOriented drilling tool
US4319649 *Jun 18, 1973Mar 16, 1982Jeter John DStabilizer
US4361193 *Nov 28, 1980Nov 30, 1982Mobil Oil CorporationMethod and arrangement for improving cuttings removal and reducing differential pressure sticking of drill strings in wellbores
US4465147 *Jan 31, 1983Aug 14, 1984Shell Oil CompanyMethod and means for controlling the course of a bore hole
US4770258 *Apr 27, 1987Sep 13, 1988Falgout Sr Thomas EWell deviation control tool
US4886130 *Jul 26, 1988Dec 12, 1989Evans Robert FNutational technique for limiting well bore deviation
US4948925 *Nov 30, 1989Aug 14, 1990Amoco CorporationApparatus and method for rotationally orienting a fluid conducting conduit
US5261498 *Jun 29, 1990Nov 16, 1993The Red Baron (Oil Tools Rental) LimitedDrill string component
US5547031 *Feb 24, 1995Aug 20, 1996Amoco CorporationOrientation control mechanism
US7278478 *Apr 27, 2005Oct 9, 2007Laclare G MauriceTubing string anchoring tool
US8074717 *Aug 1, 2007Dec 13, 2011Shell Oil CompanyDrilling method and downhole cleaning tool
USRE33751 *May 23, 1989Nov 26, 1991Smith International, Inc.System and method for controlled directional drilling
WO2010064002A2 *Dec 2, 2009Jun 10, 2010Schlumberger Holdings LimitedRotary steerable devices and methods of use
WO2015020693A1 *Mar 4, 2014Feb 12, 2015Toler Jimmy EdwardAxis offset cam tool for reverse circulation exploration drilling systems and method of use thereof
Classifications
U.S. Classification175/73, 175/325.3
International ClassificationE21B7/08, E21B7/04, E21B7/06
Cooperative ClassificationE21B7/065
European ClassificationE21B7/06F