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Publication numberUS3023821 A
Publication typeGrant
Publication dateMar 6, 1962
Filing dateMar 1, 1955
Priority dateMar 1, 1955
Publication numberUS 3023821 A, US 3023821A, US-A-3023821, US3023821 A, US3023821A
InventorsEtherington Walter H
Original AssigneeEtherington Walter H
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Well tool
US 3023821 A
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Description  (OCR text may contain errors)

March 6, 1962 w. H. ETHERINGTON 3,023,821

WELL TOOL 2 Sheets-Sheet 1 Filed March 1, 1955 Wa/zer /7. ffher/nq/m INVENTOR.

fiTTO/QNEY March 6, 1962 w. H. ETHERINGTON WELL TOOL 2 Sheets-Sheet 2 Filed March 1, 1955 MAGNET ATTORNEY United States Patent 3,023,821 WELL TOOL Walter H. Etherington, Box 907, Odessa, Tex. Filed Mar. 1, 1955, Ser. No. 491,369 6 Claims. (Cl. 175-81) The present invention relates to a well tool for positionmg a drill string laterally relative to a well bore.

In the drilling of wells by the rotary method, it is generally desirable to drill a straight hole and to drill the well as quickly as possible. It is, therefore, desirable to maintam the proper amount of weight on the drill string in order to feed the pipe into the hole at the proper rate commensurate with the type formation being drilled. In formations that might cause the bit to drill away from the vertical, it is necessary to have less weight on the drill bit to try to maintain reasonable vertical angular limits to the hole. However, even if less weight is used on the drill bit, it still may tend to drift oil its desired course. For example, if the maximum desirable deviation desired or allowable under a drilling contract is and if, by measurement means well known in the art, it is determined that the drill bit has drifted 4 01? the predetermined course, and if even though stabilizers and light weight on the drill bit do not prevent the drill bit from its continued course of drifting, then some means must be employed to bring the drill bit back on its course. The present invention could be employed, and by facing it in the desired direction in the well bore, the drill bit could be kicked over, or pushed over in the desired direction causing the hole, or well bore, to come back to a more nearly vertical hole.

Also, if the drill bit isfed through a formation at a speed not appropriate to the physical character and hardness of the formation, the drill bit may tend to move in a deviated direction from the desired path of the well bore. If the formation or stratum is hard and too much weight is applied to the bit, the bit may tend to drill in a plane at right angles to the angle of inclination of the hard stratum or it may tend to drill at an angle parallel to the stratum if the angle is steep enough. In such cases, the present tool could be used to bring the drill bit back on its desired course, or direction.

Of course, in some drilling operations it is desirable to intentionally deflect the well bore from the vertical at a predetermined angle and direction. In such cases it may be necessary to make several deflections in order to attain the desired amount of angle in the deflected well bore. Of course, if the desired deflection angle is at tained by fewer individual deflections, much time, effort and money will be saved in drilling the well bore. The present invention is directed to a well tool which is adapted to engage the wall of a well bore and may be used to position the drill string in a predetermined or desired relative or lateral position in the well bore so as to purposely change the direction of the well bore, or to increase the angle of deflection in a deviated well bore.

The invention may be used, therefore, in controlling the direction of a well bore to aid in preventing the well bore from deviating from the desired course when drilling through a crooked formation or through strata which is inclined with respect to the vertical, as previously mentioned, thereby overcoming some of the difliculties of running light drilling weights when the formation is such that heavy weights would normally increase the rate of penetration.

The invention may also be used in lieu of a whipstock to change the course of a well bore or it may be also used in building up additional angle in a well bore when a directional well bore is drilled in order to fully deflect the well bore the desired amount with a minimum number of separate deflections.

"ice

An object of the present invention is to provide a well by providing a member for engaging the wall of the well bore and then urging the drill string in a predetermined direction relative to the well bore.

Still another object of the invention is to provide a well tool for fitting on the drill string in a well bore, which tool may be engaged with the Wall of a well bore for urging the drill string laterally of the well bore when the tool is actuated.

Still another object of the invention is to provide a' sleeve on a drill string, which sleeve has a longitudinally extending slot therein, there being fluid passage means communicating the sleeve with the drill string for conducting fluid pressure from the drill string to the sleeve and a resilient member mounted in the sleeve and covering said slot whereby application of fluid pressure in the sleeve expands said member outwardly of the slot to en-;

gage the wall of the well bore and urge the drill string laterally relative to the well bore.

Still another object of the invention is to provide a well tool for fitting on the drill string in a well bore and means for orienting the tool in the well bore so that the tool may engage the well bore wall to urge the drill string laterally of the well bore in a predetermined or desired manner.

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

FIG. 1 is an elevation illustrating the present invention as being used for aiding in deflecting a well bore;

FIG. 2A is a vertical sectional view, partly in elevation, illustrating the upper portion of the preferred embodiment of the invention;

FIG. 2B is a vertical sectional view, partly in elevation, and is a continuation of 2A illustrating the lower part of the tool;

FIG. 3 is a sectional view on the line 3-3 of FIG. 2A;

and

FIG. 4 is a sectional view illustrating the present invention actuated and the drill string moved to one side of the well bore.

In FIG. 2A the invention is indicated generally by the numeral 3 and is shown as including the hollow tubular mandrel 4 which is provided with suitable threaded means as illustrated in dotted line at 5 for engaging the upper end thereof with the drill string and is provided with the threaded means 6 at its opposite end for en,- gaging the drill string illustrated at dotted line 7. The mandrel 4 may be of any suitable length without departing from the scope of the present invention. For purposes of illustration and description only, it will be assumed that the mandrel 4 is twenty feet in length.

A sleeve 9 is slidably mounted on the tubular mandrel 4 and is provided with packing 1t) and 11 adjacent each end of such sleeve for sealably engaging with the outer periphery 12 of the hollow mandrel 4.

The seal means 10 and 11 may be of any suitable type and is shown in the drawings as being of the chevron type which is maintained in position by the retainers 13 and 14 and the hold down nut 15. The above packing arrangement permits relative longitudinal and rotational movement between the tubular mandrel 4 and the sleeve 9 as will be more fully described hereinafter, but forms a seal between the mandrel 4 and sleeve 9 to provide the chamber 17 within the sleeve 9. The hold down nut 15 on the lower end of the sleeve may be integrally connected with the clutch element 51, as will be more fully discussed herein.

As previously mentioned, the tubular mandrel 4 is hollow and, in eifect, is a part of the drill string 7 which is used in drilling the well bore. During drilling operations, mud fluid is circulated downwardly through the drill string, discharged at the bit and then circulated upwardly in the well bore about the drill string. The present invention is constructed so as to utilize such pressure fluid for operation of the present invention. Passage means 19 in hollow mandrel 4 communicates the longitudinally extending passage 20 of mandrel 4 with the chamber 17 formed in the sleeve 9 for conducting the fluid from drill string 7 to the sleeve 9. The sleeve 9 is provided with a longitudinally extending slot 36and the member 21 mounted in the sleeve is adapted to move outwardly through the slot 36 upon the application of fluid prsesure in chamber 17 so as to contact the wall 22 of well bore 23 as shown in FIG. 4. When the member 21 contacts the well bore wall 22, the drill string 7 is urged in an opposite direction or is moved laterally relative to the well bore 23 as shown in FIG. 4. The member 21 is illustrated in the present embodiment as being formed of resilient material, such as rubber or the like, which expands upon the application of fluid pressure in chamber 17 between sleeve 9 and mandrel 4 whereby such member is moved outwardly on one side of and relative to the sleeve 9. It seems obvious that other modifications of the member 21 could be provided so that such member moves outwardly of the sleeve 9 to engage the well bore wall opposite thereto to move the drill string laterally of the well bore, and the illustration in the drawings is but one of many which will operate and function satisfactorily to accomplish the desired results.

The resilient member 21 is shown as being provided with the enlarged portion 43 which fits within the longitudinally extending slot 36 of sleeve 9. The enlargement 43 has integrally connected therewith the side portions 30' of reduced thickness as illustrated in FIGS. 3 and 4, which side portions also extend beyond the enlargement 43 at the upper and lower end thereof to form end projections as shown at 30 and 31 in FIGS. 2A and 2B.

Suitable means for securing the member 21 within the sleeve 9 is shown in the drawings as including the annular longitudinally extended retainer 25 which rests on shoulders 26 and 27 at each end respectively of sleeve 9. The retainer is annularly recessed as illustrated at 28 to provide a space for receiving the side portions 30 and the end projectings 30 and 31 of member 21 whereby such member is maintained in position in the sleeve 9 between retainer 25 and the inner periphery 33 of the sleeve 9.

Such arrangement serves not only to position the resilient member 21 within the sleeve 9 but holds the member 21 relative to the sleeve '9 during expansion thereof. It should be further noted that the retainer 25 is provided with a longitudinally extending slot or opening 35 which fits adjacent the slot 36 whereby fluid pressure may be applied to the member 21 from chamber 17 to expand enlargement 43 against the wall of the well bore.

The longitudinally extending slot 36 in sleeve 9 has its ends 38 and 39 terminating at points spaced from the ends of the sleeve 9. If desired, the inner portion 41 of such ends may be tapered to accommodate expansion of the resilient member 21 without cutting or breaking due to undue bending thereof.

In order to orient the tool in the well bore so that the longitudinally extending slot 36 will face in a predetermined or desired direction, suitable means illustrated generally at 47 are provided.

Such means includes the clutch element 48 on mandrel 4 which is provided with grooves 49 therein which are adapted to engage with projections 50 of the clutch element 51 on sleeve 9 whereby the drill string and the sleeve 9 may be rotated as a unit to orient the tool in the Well bore. As shown in the drawings, the clutch element 51 may be integrally connected with the hold down nut 15 on thelowerend of sleeve 9. The cooperating grooves or surfaces 49 and 50 of each element may be engaged to orient the tool in the well bore and may then "be disengaged after the tool has been actuated by relative longitudinal movement between the drill string in which mandrel 4 is connected and the sleeve 9.

This construction permits the tool and drill string to be connected or locked together whereby the tool may be oriented to position it in the well bore so as to face slot 36 of sleeve 9 in a desired direction. Thereafter the pump pressure may be increased so that member 21 may be urged outwardly through opening 36 to contact enlargement '43 thereof against the well bore wall 22. This moves the drill string laterally of the well'bore and also positions sleeve 9 so as to allow the drill string and :mandrel 4 connected therewith to move downwardly to disengage clutch elements 48 and 51.

After the clutch elements have been disengaged, the drill string may be rotated to continue normal drilling operations.

While it is believed that the operation of the invention is apparent by reason of the foregoing description, to further amplify and describe, the operation of the tool will be discussed under several conditions.

If the tool is to be used to aid in maintaining a straight hole, or to maintain a hole on a desired course, the mandrel 4 and sleeve 9 may be connected on the well string 7 and lowered into the hole. When the tool is to be used in this manner, a magnetic section may be placed in the sleeve in a predetermined relationship relative to the rib 43. Such magnetic portion is illustrated at 70 and may be aligned with respect to the enlargement so that they face in opposite directions. A tool of a well known type, which is well known in the art (as shown for example in Patent 2,327,658), may be lowered into the drill string until it rests on the seat 71 in the hollow mandrel 4. Such tool in cooperation with the magnetic section 70 determines the high and the low side of the well bore. With this information the drill string may be rotated so as to face the enlargement 43 of the tool 3 in the desired direction.

Of course, when the tool is originally lowered into the well bore, the clutch elements 48 and 51 on the mandrel 4 and sleeve 9 respectively are engaged and maintain such relationship as the tool is oriented in the well bore. By increasing the mud pump pressure at the surface of the well bore, a greater pressure is built up in the drill string than that existing in the well fluid in the well bore 23 on the outside of the drill string. This increase in pressure is transmitted through the port 19 to chamber 17 where it acts upon the member 21 so as to move the enlargement 43 against the wall of the well bore as illustrated at 43' in FIG. 4 of the drawings.

The engagement of the enlargement 43 of member 21 with the well bore wall causes the drill string to move laterally thereof so that the drill bit on the lower end thereof is brought back towards its desired course. The drill string may be lowered relative to the sleeve 9 so as to disengage the clutch elements 48 and 51 and drilling operations continued.

The amount of travel of the drill string is limited by the length of sleeve 9. Port 19 is shown in dotted line at 19 in its initial position when the sleeve 9 and tubular member 4 are engaged together by their clutch elements 51 and 48 respectively. After the enlargement 43 has positioned the sleeve 9 so that the drill string can be lowered relative thereto, the drill string upon rotation continues its normal drilling operations until the port19 in the mandrel 4 reaches its lowermost position as illustrated at 19". To prevent the port 19 from moving by packing 11 in the lower end of the sleeve, a collar 72 may be positioned on the mandrel above the sleeve a proper distance equivalent to the distance between the positions of the port 19 as illustrated at 19' and 19".

FIG. 1 illustrates the invention as being used for aid ing in deflecting a drill bit so as to change the direction of the well bore. In such event, it may be desirable to form the tool of suitable material soastonot-interferc t) with the device which is lowered into the well string so that the tool may be oriented in a proper manner to change the course of the well bore to a desired direction.

As previously described, the orienting tool or device is well known in the art and the drill string may be rotated so as to face the enlargement 43 in a desired direction.

The pump pressure may then be increased so as to move the drill string laterally of the well bore. The drill string 7 having been moved laterally of the well bore by the device may be lowered to disengage the clutch elements and drilling operations continued until the port 19 has moved from its position as illustrated at 19' to its position as illustrated at 19" as previously described.

When the pump is cut off so that the pressure on the mud column in the drill string and in the well bore is equalized the member 21 will deflate and the sleeve 9, due to its weight, will slide along the mandrel 4 whereby the clutch elements 51 and 48 may be reengaged. The procedure may then be repeated as desired. The sleeve 9 may be of any desired length, but in order to permit as much travel of the drill string as possible before resetting the tool, the length of the sleeve should not be greater than approximately one-half the length of the mandrel. Therefore, since for purposes of illustration, it has been assumed that the mandrel is twenty feet long, it may be assumed that the length of the sleeve is ten feet. Under such conditions, and after the tool has been actuated, the drill string can be moved, or drilled down 8 or 9 feet before it is necessary to reset the tool.

In FIG. 1 the normal well bore is illustrated at 55 and the device is illustrated generally at 3 as having been positioned in the well bore and oriented so that the bulge 43 of member 21 contacts the well bore to urge the drill string to one side of the well bore. After the device 3 has been oriented and positioned in the well bore by increasing pump pressure, the drill string 7 may be lowered to disengage clutch elements 48 and 51. Rotation of the drill string then causes the drill bit 7' to move downwardly to deflect the well bore as illustrated at 57 in FIG. 1.

Broadly the invention relates to a well tool for positioning a drill string laterally relative to a well bore whereby the direction of the well bore may be controlled.

What is claimed is:

l. A well tool for engaging the wall of a well bore during the longitudinal and rotational movement of a tubular drill string comprising, a longitudinally extending sleeve siidably mounted on the drill string for longitudinal movement relative thereto and having an annular inner space therebetween, said sleeve having at least one opening extending laterally therethrough, said opening being of lesser circumferential and longitudinal extent than said sleeve, wall engaging means mounted in said opening in normally retracted relationship relative to the wall of the well bore, the inner portion of said wall engaging means communicating with said annular inner space and movable outwardly by fluid pressure from the annular space to engage the wall of the well bore, longitudinally spaced upper and lower seal means between said sleeve and said drill string to inhibit leakage of fluid from said sleeve, said annular space extending from said upper seal means to said lower seal means, and passage means in the wall of the drill string and movable therewith relative to said sleeve between said upper and lower seal means while communicating fluid from the interior of said drill string to said annular space between said drill string and said sleeve during longitudinal and rotational movement of said drill string relative to said sleeve.

2. A well tool for engaging the wall of a well bore during the longitudinal and rotational movement of a tubular drill string comprising, a longitudinally extending sleeve slidably mounted on the drill string for longitudinal movement relative thereto and having an annular inner space therebetween, said sleeve having at least one opening extending laterally therethrough, said opening being of lesser circumferential and longitudinal extent than said sleeve, wall engaging means mounted in said opening in normally retracted relationship relative to the wall of the well bore, the inner portion of said wall engaging means communicating with said annular inner space and movable outwardly by fluid pressure from the annular space to engage the wall of the well bore, longitudinally spaced upper and lower seal means between said sleeve and said drill string to inhibit leakage of fluid from said sleeve, said annular space extending from said upper seal means to said lower seal means, and passage means in the wall of the drill string and movable therewith relative to said sleeve between said upper and lower seal means while communicating fluid from the interior of said drill string to said annular space between said drill string and said sleeve during longitudinal and rotational movement of said drill string relative to said sleeve, said wall engaging means including an elastic flexible element mounted in said sleeve and extending across said opening in said sleeve for expansion outwardly of said sleeve by the fluid pressure from the drill string and for retraction inwardly by the inherent elasticity of said element when the fluid pressure is reduced from the amount required to expand said element.

3. A well tool for engaging the wall of a well bore during the longitudinal and rotational movement of a tubular drill string comprising, a longitudinally extending sleeve slidably mounted on the drill string for longitudinal movement relative thereto and having an annular inner space therebetween, said sleeve having at least one opening extending laterally therethrough, said opening being of lesser circumferential and longitudinal extent than said sleeve, wall engaging means mounted in said opening in normally retracted relationship relative to the wall of the well bore, the inner portion of said wall engaging means communicating with said annular inner space and movable outwardly by fluid pressure from the annular space to engage the wall of the well bore, longitudinally spaced upper and lower seal means between said sleeve and said drill string to inhibit leakage of fluid from said sleeve, said annular space extending from said upper seal means to said lower seal means, and passage means in the wall of the drill string and movable therewith relative to said sleeve between said upper and lower seal means while communicating fluid from the interior of said drill string to said annular space between said drill string and said sleeve during longitudinal and rotational movement of said drill string relative to said sleeve, said wall engaging means having a total circumferential extent which is less than the circumferential extent of said sleeve whereby drilling fluid may be circulated in the well bore when said wall engaging means engages the wall of the well bore.

4. A well tool for engaging the wall of a well bore during the longitudinal and rotational movement of a tubular drill string comprising, a longitudinally extending sleeve shdably mounted on the drill string for longitudinal movement relative thereto and having an annular inner space therebetween, said sleeve having at least one opening extending laterally therethrough, said opening being of lesser circumferential and longitudinal extent than said sleeve, wall engaging means mounted in said opening in normally retracted relationship relative to the wall of the well bore, the inner portion of said wall engaging means communicating with said annular inner space and movable outwardly by fluid pressure from the annular space to engage the wall of the well bore, longitudinally spaced upper and lower seal means between said sleeve and said drill string to inhibit leakage of fluid from said sleeve, said annular space extending from said upper seal means to said lower seal means, passage means in the wall of the drill string and movable therewith relative to said sleeve between said upper and lower seal means while communicating fluid from the interior of said drill string to said annular space between said drill string and said sleeve during longitudinal and rotational movement of said drill string relative to said sleeve, and co -acting stop means on said drill string and said sleeve to limit the downward movement of said drill string relative to said sleeve during the rotational and longitudinal movement of said drill string relative to said sleeve to prevent said passage means from moving below said lower seal means.

5. A well tool for engaging the wall of a well bore during the longitudinal and rotational movement of a tubular drill string comprising, a longitudinally extending sleeve slidably mounted on the drill string for longitudinal movement relative thereto and having an annular inner space therebetween, said sleeve having at least one opening extending laterally therethrough, said opening being of lesser circumferential and longitudinal extent than said sleeve, wall engaging means mounted in said opening in normally retracted relationship relative to the wall of the well bore, the inner portion of said wall engaging means communicating with said annular inner space and movable outwardly by fluid pressure from the annular space to engage the wall of the well bore, longitudinally spaced upper and lower seal means between said sleeve and said drill string to inhibit leakage of fluid from said sleeve, said annular space extending from said upper seal means to said lower seal means, passage means in the wall of the drill string and movable therewith relative to said sleeve between said upper and lower seal means while communicating fiuid from the interior of said drill string to said annular space between said drill string and said sleeve during longitudinaly and rotational movement of said drill string relative to said sleeve, and cooperating clutch means on said sleeve and the drill string adapted when engaged to retain said sleeve on the drill string in a predetermined position as the well tool is lowered in the well bore.

6. A well tool for engaging the wall of a well bore and urging a tubular drill string laterally during the longitudinal and rotational movement of the drill string comprising, a longitudinally extending sleeve slidably mounted on the drill string for longitudinal movement relative thereto and having an annular inner space therebetween, said opening being of lesser circumferential and longitudinal extent than said sleeve, said sleeve having an opening extending laterally therethrough on only one side of said sleeve, wall engaging means mounted in said opening in normally retracted relationship relative to the wall of the well bore, the inner portion of said wall engaging means communicating with said annular inner space and movable outwardly by fluid pressure from the annular space to engage the wall of the well bore and urge the drill string laterally in the well bore, longitudinally spaced upper and lower seal means between said sleeve and said drill string to inhibit leakage of fluid from said sleeve, said annular space extending from said upper seal means to said lower seal means, and passage means in the wall of the drill string and movable therewith relative to said sleeve between said upper and lower seal means while communicating fluid from the interior of said drill string to said annular space between said drill string and said sleeve during longitudinal and rotational movement of said drill string relative to said sleeve.

References Cited in the file of this patent UNITED STATES PATENTS 712,887 Wyczynski Nov. 4, 1902 2,316,409 Downing Apr. 13, 1943 2,643,722 Lynes et al June 30, 1953 2,643,859 Brown June 30, 1953 2,696,367 Robishaw Dec. 7, 1954 2,715,552 Lane Aug. 16, 1955 2,734,721 Zublin Feb. 14, 1956 2,745,635 Zublin May 15, 1956 2,796.234 Mann June 18, 1957 2,807,326 Church Sept. 24, 1957 2,824,612 Lynes Feb. 25, 1958 2,946,565 Williams July 26, 1960

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3126971 *Oct 26, 1960Mar 31, 1964 Drill string stabilizer
US3259193 *Feb 9, 1960Jul 5, 1966Exxon Production Research CoRetractable drill collar stabilizer
US3298449 *Oct 24, 1963Jan 17, 1967Drilco Oil Tools IncWell bore apparatus
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Classifications
U.S. Classification175/81, 175/61, 175/230, 166/212, 175/76
International ClassificationE21B7/06, E21B7/04, E21B7/08
Cooperative ClassificationE21B7/062
European ClassificationE21B7/06C