US3765494A - Circulating sleeve - Google Patents

Abstract

In a drilling system, a subassembly provides a means for seating an instrument housing in the drill string during a drilling operation and for permitting a normal flow of drilling fluids around the instrument housing. The seat also provides means for orienting the instrument housing in a predetermined position relative to a portion of the drill system.

Description

1451 Oct. 16, 1973 United States Patent 1191 Kielman, Jr.

l75/4.5l X Alberts 175/451 175/44 CIRCULATING SLEEVE 2,361,204 171323 Howard etal.

[75] Inventor: Fred 3,450,216 6/1969 l-lugeletal.

[73] Assignee: Sperry-Sun WellSurveying Company, Sllgarland,T X- Primary Examiner-David H. Brown [22] Filed, Apr 21 1972 Attorney-George L. Church et a1.

Applv No.: 246,293

[57] ABSTRACT In a drilling system, a subassembly provides a means for seating an instrument housing in the drill strin during a drilling operation and for permittin flowof drilling fluids around the instrume [52] US Cl 175/320, 175/45 [51] Int. E2lb l7/00 g a normal nt housing.

[58] Field oi Search...................... l75/4.5l, 44, 45, 175/73, 75, 61, 320, 324

The seat also provides means for orienting the instr ment housing in a predetermined position relative to a [56] References cued portion of the drill system.

UNITED STATES PATENTS 5 Claims, 3 Drawing Figures PATENIEnum 16 I975 3 765 494 sum 1 OF 2 y In l \3 PATENTED OCT 16 I373 SHEET 2 OF 2 FIG. 2

BACKGROUND OF THE INVENTION The present invention pertains to a circulating sleeve and more particularly to an apparatus for orienting an instrument within a drill string and providing for the circulation of fluid about the instrument tov permit drilling when an instrument is seated therein.

When drilling boreholes in the earths surface it is often desirable for various reasons to deviate the holes from a vertical course through the earth formations. The term directional drilling is applied to such operations. One example of the use of such directional drilling operations is found in the drilling of oil wells from offshore platforms. It is a common practice to build large drilling platforms which are permanently secured to the ocean floor and from which a multiplicity of wells are drilled. Because of the number of wells which are drilled from a single platform, it is necessary to drill the holes laterally away from the platform so that earth formations containing petroleum reservoirs may be penetrated at distances laterally spaced from the platform. This procedure permits production from as great an area as possible from a single platform. It is easily understood how important the maintenance of direction and dip of such boreholes is in order to penetrate particular formations at predetermined depths and thereby intersect the desired petroleum reservoirs.

One technique for obtaining such information as to the direction of a borehole is to cease drilling and run a surveying instrument into the drill pipe on a wire line. Alternatively, the instrument may be go-deviled to the bottom of the drill pipe. The instrument is oriented with respect to the drill stem by means of a muleshoe sub located at the lower end of the drill stem. The muleshoe" is simply a device for capturing the tool and orienting the tool in a predetermined radial direction with respect to a position on the drill ste'm. For example, the drill stem normally used in such'a directional drilling operation includes what is normally termed a bent sub," at its lower end which places a bend in the lower end of the stem and thereby permits angular deviation of the drill bit. The muleshoe" is normally oriented with respect to the bent sub. This in turn orients the instrument which is being positioned in the lower end of the drill stem. This series of orientation procedures provides a correlation between the direction in which the drill bit is angled and the directional alignment of the survey instrument. After the survey instrument is operated to generate a record, generally be means of a timing mechanism, the tool is retrieved to the surface by means of a wire line. The record is then processed and examined to determine the direction in which the hole is being drilled. a

More recently, techniques have been developed f passing an instrument into the drill stern by means of a conductor cable to provide continuous directional information to the surface during the drilling operation. This technique also utilizes the method described above of locating the instrument within a muleshoe which in turn is oriented in a particular radial direction with respect to a bent sub" in the drill string. Thus, the information which is received at the surface indicative of the direction in which the survey instrument is positioned is correlated with the direction that the bit is angled.

It is common in such directional drilling operations to use a mud motor or turbine for rotating the drill within the borehole. Such a motor or turbine requires the continuous circulation of drilling fluidsthrough the motor to provide the power for turning the drill. Therefore, it is essential that a constant flow of drilling fluids be maintained through the system even while an instrument is positioned within the drill stem.

It is therefore an object of the present invention to provide a new and improved circulating sub for receiving an orientation instrument within a drill string.

SUMMARY OF THE INVENTION With this and other objects in view, the present invention contemplates a drill pipe having a recessed portion therein forming a seat within the bore of the pipe. A sleeve which is sized for reception within the recessed portion has a shoulder which when received within the recess mates with the seat. A plurality of Iongitudinal ribs are formed on the sleeve and extend upwardly from the shoulder. Means extend inwardly from the sleeve for engaging a mating surface on an instrument housing to thereby locate the instrument in a predetermined manner within the sleeve.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIG. 1 of the drawings, the lower end of the'drill stem is shown including adrill collar 27 and amuleshoe orienting sub 28. Abent sub 29,mud motor'or turbine 31, and a rotatingbit sub 32 are positioned below the orienting sub. An instrument which for the purpose of this disclosure shall be referred to as anorienting tool 33, is shown positioned within the interior bore of the drill collar and is connected at its upper end with aconductor cable 26 extending to the surface. Typically, the conductor cable would extend through a line wiper at the surface and be taken up on a motor driven drum which permits its playout and take up during operations. The line wiper is constructed to seal off well pressure at the wellhead during line operations in the drill pipe.

Referring again to the lower end of the drill stern, a

muleshoe sleeve 34 is shown positioned within themuleshoe orienting sub 28 and is oriented therein in a predetermined fashion. Thesleeve 34 is held in the predetermined position within the sub by means of a screw or the like 36 extending through the side wall of thesub 28. Themuleshoe sleeve 34 is shown having a key 37 positionedin its sidewall and extending inwardly into the sleeve bore. The muleshoe and its key are normally oriented directionally with respect to the bent sub and thus with respect to the drill bit which derives its direction of inclination by means of the bent sub. This predetermined alignment of the muleshoe key with respect to the bent sub is convenient for purposes of determining the original orientation of the drill with respect to surface indications of tool direction and thereafter for making compensating changes in drilling direction. The muleshoe sleeve or circulating sleeve as it will be hereinafter referred to, may be utilized to positionally locate various types of instruments within a drill 'pipe; however, since one of its primary uses is for locating directional drilling orienting instruments this disclosure will continue to use such an instrument as an example.

Theorienting tool 33 which is shown schematically in FIG. 1 includes amuleshoe 39 which is secured to the lower end of the tool string. The muleshoe includes a protruding shaft or stinger 41 having a tapered end 42 (see FIG. 2) for guiding the stinger into themuleshoe sleeve 34. Ashoulder 43 extends spirally around'opposite sides of the stinger, meeting at apointed terminus 44, to form a camming surface. On the opposite side of the tool from theterminus 44, thespiral shoulders 43 meet to form a short longitudinally extendingslot 45. Theslot 45 is sized to receive the inwardly extendingkey 37 on themuleshoe sleeve 34 when thetool 33 is positioned in the drill pipe. Thetool string 33 further includes a muleshoe adjuster which permits rotation of themuleshoe 39 relative to thetool string 33. The adjuster includes includes mating portions (not shown) between the muleshoe and tool string to permit relative rotation therebetween, and alocking collar 35 for securing the tool string and muleshoe in a fixed rotational position. Greater detail of the muleshoe and its functional use with an orienting tool is shown in co-pending U.S. Pat. application Ser. No. 86,877, now U.S. Pat. No. 3,7l8,l94, which is assigned to same assignor as the present application.

Referring next to FIG. 2 of the drawings, thecirculating sleeve 34 and its cooperative relationship with thesub 28 is shown in greater detail.Sub 28 has arecessed bore portion 46 with atapered seat 47 at its lower end. The circulatingsleeve 34 is shown positioned within thesub 28. Thesleeve 34 has abody portion 49 withlongitudinal ribs 48 extending outwardly therefrom into contact with the recessedinner bore portion 46 of thesub 28. Thelongitudinal ribs 48 extend downwardly below the lower end of thebody portion 49. Acylindrical sleeve 51 is formed at the bottom end of the longitudinal ribs. Tapered top andbottom surfaces 52 and 53, respectively, are formed on thesleeve 51. Thelower surface 53 is arranged to matingly seat on the taperedsurface 47 of the recessed bore 46 insub 28. Upper and lowerperipheral grooves 54 and 56, respectively, are formed on the surface of the exterior wall ofsleeve 51, and are sized to receive O-ring seals therein. Anotherperipheral groove 57 is formed between thegrooves 54 and 56 in the outer wall of thesleeve 51 for receiving an inwardly extending end portion of aset screw 36. Thebody portion 49 of the circulatingsleeve 34 and one of thelongitudinal ribs 48 have an'aligned opening formed through the rib and body portion for receiving the key 37. The key 37 has anenlarged shoulder portion 61 formed thereon which abuts a complimentary shoulder formed in the rib opening.

In the operation of the system described herein the following method is employed: the circulatingsleeve 34 is inserted into the upper end ofsub 28 until the lower taperedsurface 53 onsleeve 51 is matingly seated on taperedsurface 47 within the bore ofsub 28. The circulating sleeve is then rotated within the bore ofsub 28 until the key 37 which extends inwardly from the sleeve is positioned in accordance with a predetermined arrangement to permit orientation with respect to a portion of the drill stem. Normally, the predetermined alignment of the key 37 is in some relationship with thebent sub 29 so that it is known that the muleshoe key 37 is pointing in a particular direction with respect to that in which the drill is pointing. This arrangement provides means for determining, by means of an orienting instrument to be located within the muleshoe sub in what direction the drilling operation is being conducted. In any event, after the key 37 and the circulating sub has been oriented within thesub 28, setscrews 36 are rotated until they extend inwardly into thegroove 57 onlower sleeve 51 and tightened therein to hole the sleeve in a fixed relationship with thesub 28 and thereby prevent its rotation within the sub. Next, thesub 28 is made up in the drill string and the drill string is lowered into the wellbore for purposes of performing the drilling operation.

Thereafter, when it is desired to lower an instrument into the drill stem by means of thecable 26 shown in FIG. 1, such instrument is lowered until themuleshoe stinger 41 extends into the circulatingsub 34 whereupon thespiral camming surface 43 thereon engages the key 37 and produces a camming action to rotate the muleshoe until thelongitudinal slot 45 of the muleshoe drips over the key 37. The procedure thus far described permits the instrument housing located above the muleshoe to be radially positioned within the drill stem in a predetermined manner. The arrangement of the circulating sub, seat and muleshoe permits the circulation of drilling fluids through the drill stem even when the instrument and muleshoe are seated within the drill string. This is provided by means of the annular spaces between thelongitudinal ribs 48 and between thesleeve 51 and the lower end of the muleshoe. The path of such fluid circulation is shown by the arrows in FIG. 2.

With the circulating sub described herein the volume of fluid that may be circulated through the system is sufficient to drive the mud motor or turbine during drilling operations while permitting the continuous use of an orienting instrument.

Wile a particular embodiment of the present invention has been shown and described, it is apparent that changes and modifications may be made without departing from this invention in its broader aspects and therefore the aim in the appended claims is to cover all such changes and modifications as which fall within the true spirit and scope of this invention.

What is claimed is:

1. In a drilling system utilizing a hollow conduit for carrying a drilling fluid means for seating an instrument housing within the conduit while performing a drilling operation, which means includes: a seat formed within the bore of said conduit, a sleeve sized for reception within the bore of said conduit, shoulder means on one end of-said sleeve for providing a mating reception of said sleeve within said seat, said shoulder means being sized for close fitting reception within said conduit, a plurality of longitudinal ribs on said sleeve extending above said shoulder means and key means extending inwardly from said sleeve for orienting an instrument housing.

2. The apparatus of claim 1 and further including a transverse opening extending through one of said ribs and sleeve for receiving said key means.

3. The apparatus of claim 1 and further including means of locking said sleeve against relative movement with said conduit.

4. The apparatus ofclaim 3 wherein said locking means extends through the wall of said conduit and further including seal means on said shoulder arranged to be positioned above and below said locking means when said sleeve is seated in said conduit.

5. A circulating sleeve for seating and orienting an instrument housing within the bore of a drill pipe during a drilling operation and arranged to permit the flow of fluids through the drill pipe when an instrument housing is positioned therein, comprising: a sleeve for reception within the bore of the pipe, and having a cylindrical portion with longitudinal ribs formed thereon for engaging the bore of the pipe and maintain said cylindrical portion in a spaced position from said bore; a shoulder formed on said sleeve for engaging a seat in the pipe; key means extending from the wall of said cylindrical portion into its bore for engaging a portion of the instrument housing to orient the housing with respect to said sleeve; and means on said sleeve for receiving a member extending from the wall of the pipe for holding said sleeve against rotation relative to the pipe.

Claims (5)

1. In a drilling system utilizing a hollow conduit for carrying a drilling fluid means for seating an instrument housing within the conduit while performing a drilling operation, which means includes: a seat formed within the bore of said conduit, a sleeve sized for reception within the bore of said conduit, shoulder means on one end of said sleeve for providing a mating reception of said sleeve within said seat, said shoulder means being sized for close fitting reception within said conduit, a plurality of longitudinal ribs on said sleeve extending above said shoulder means and key means extending inwardly from said sleeve for orienting an instrument housing.

2. The apparatus of claim 1 and further including a transverse opening extending through one of said ribs and sleeve for receiving said key means.

3. The apparatus of claim 1 and further including means of locking said sleeve against relative movement with said conduit.

4. The apparatus of claim 3 wherein said locking means extends through the wall of said conduit and further including seal means on said shoulder arranged to be positioned above and below said locking means when said sleeve is seated in said conduit.

5. A circulating sleeve for seating and orienting an instrument housing within the bore of a drill pipe during a drilling operation and arranged to permit the flow of fluids through the drill pipe when an instrument housing is positioned therein, comprising: a sleeve for reception within the bore of the pipe, and having a cylindrical portion with longitudinal ribs formed thereon for engaging the bore of the pipe and maintain said cylindrical portion in a spaced position from said bore; a shoulder formed on said sleeve for engaging a seat in the pipe; key means extending from the wall of said cylindrical portion into its bore for engaging a portion of the instrument housing to orient the housing with respect to said sleeve; and means on said sleeve for receiving a member extending from the wall of the pipe for holding said sleeve against rotation relative to the pipe.

Images