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Publication numberUS2815930 A
Publication typeGrant
Publication dateDec 10, 1957
Filing dateFeb 23, 1954
Priority dateFeb 23, 1954
Publication numberUS 2815930 A, US 2815930A, US-A-2815930, US2815930 A, US2815930A
InventorsStorm Lynn W
Original AssigneeStorm Lynn W
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Drill pipe stabilizer and guide bushing
US 2815930 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Dec. l0, 1957 l xl L. W.. STORM DRILL PIPE STABILIZER AND GUIDE BUSHING 3 Sheets-Sheet 1 v INVENTOR.

ATTORNEY Dec. 10, 1957 l.. w. STORM DRILL PIPE STABILIZER AND GUIDE BUSHING Filed Feb. 23, 1954 5 Sheets-Sheet 2 ATTORNEY Bgm m; v1957- F'iled Feb. 2:5, -19

L. W. STORM DRILL PIPE STABILIZER AND GUIDE BUSHING 3 Sheets-Sheet 3 l A TTU/PNE Y nited States Patent O DRILL PIPE STABILIZER AND GUIDE BUSHING Lynn W. Storm, Austin, Tex.

Application February 23, 1954, Serial No. 411,918

6 Claims; (Cl. Z55-27) This invention relates to adrillpipe stabilizer and guide bushing, andk more particularly to a device for application tol arotary drill stem and which is engageable with theh interior of the bore of a well to guide and center the drill:v stemY therein.

In the rotary method of well drilling the downward progre-ss of the drill bit. isf opposed by tremendous forces depending on. the type of. bit, hardness or toughness of ormatiomdepth of the well,` and many other factors. The drill pipe employed in rotaryv drilling is the sole physical connection betweeny the bit and thev prime mover at the wellt surface, so. thatV all the hammering, beating, twisting, and turning thatfthebit endures-mustrstbe borne by the drilli pipe. lnk addition to the abuse that the bit suffers the drillpipe is exposed` to various other stresses.` One of the most severe stresses imposed on the pipe is the accumulatedx torque asfa result` of friction` duetoV the rotation of the drill. collars and pipezinoontact with the` interior of the welL bore. rlhis factor` is influencedby the. relation of, hole size topipersize, crookedness: of the hole, cosef.- ficientof friction betweenfpipe. and formation andmany othen factors. Another form of stress. suieredl by the drillpipe, and` oftenV acause of pipevv failures is the unayoidablewobblin'ggin,therstringas it` rotates. The wobble ortransverse flexingtis. more=pronounced ini-portions of the hole.l in which`V thep course of, drift. changes, in` direction where aijoint of. pipe has aislightlkink or bend, and at theflower end: ofv thestringwhere, they pipe is,in neither tensionnorL compression;the flexing point-beingdependent on the amount;-ofweightbearng onthe bit.

Another difficulty frequentlyencountered'in.the drilling ofwellsrby.) ithenotary process isfthe formation of key. seats in thewell bore due tothe curvaturefofithe bore., and the engagement ofthe;` jgints of the drill` stemswith-the wall of-thegboresatithe locationof suchcurves', such-.joints-being ofgsrnallen-dianieter thanthe,drill.2bit, sok thatsuch. key seats are of substantially smaller diameter'` than the Vdiameterg'of thet bore- ,ffr..l: eyAfv seat. may be formedfina-hole hy',r the, breaching action, of, the, drill `pipesjoints` asw they passlaround curves., o r. crooked spots: ontrips#` in and. out of;r the hole, In removingthefdrillpipe from, the hole thereaisl a tendency:for.l the pineto, beffpulledf in aastraight line since the pipe is in tensionyand anyfpoint-infthe hole not; on r,this straightdine will -eventuallyfbe ,wornr `backby theTlv dragging; ovv therjoints, The tresultant broachedportion ,of thjehole is,.of the,approxim'atecdiameterr of the jointswhich isrsubstantially less than-,thediameter of the drill :bin Thus, a keyfseatfconstitutestanundesirable,hole condition -likely .toI cause sticking of the drillvrpipe on-trips Out-10i the helel Ther present invention has for-z ant-,important Lobjectthe provision got.;meansadaptedrto-.be` connected-,into `a drill pipe.Z or stringi, whereby the.abovediiculties in carrying out well drilling operations by` therotary drilling process mayw b'ehovercome land by which a., substantial reduction may' bepaccomplishedfin th'e stress and strainjimposed `on the j drill pipe due to' friction andwobbling of the drill pipe in'the wellxbore:

Mice

Another object of the invention is to provide a drill pipe stabilizer and guide bushing by which the drill collars and pipe may be maintained in a centered position in the well bore to aid in the drilling of avstraight as welll as a vertical hole, and which may also serve to, guide the' drill collar' and bit past a key seat or to wipe or ream: the key seat in the event that it becomes necessary to do so. r

A further object of the invention is the provision of a drill collar stabilizer and guide bushing which is con? structed to rotate freely relative to thev drill stern to4 which it is applied, and which may also be operated to cause` the device to rotate with the drill stem for use as a key seat wiper or reamer when desired. y Y

Another object of the invention is to provide a drill collar stabilizer and guide bushing device, which may also be operated `as a keyv seat reamer andin which the operating parts of the device are protected against abrasion or other injury due toexposure t-o well fluid or contact with other foreign matter,

A further object of the invention is the provision of a drill stem stabilizer and guide bushing which is capable of operation' to perform a jarring action in the event of sticking of they device in the well' bore, to eifect the release of the device or to facilitate its action in wiping or reaming out a key seat. A

A stilll further objectl of the invention is the provision of a drill collar stabilizer and guide bushing which is of simple design and rugged construction, capable of withstanding the extreme conditions of wear and hard usage towhich such equipment is customarily subjected.

The aboveand other'important objects and advantages of the. invention, will best beunderstood from the followingdetail'ed description,constituting aspecification of the same, when considered in conjunction with the annexed drawings,y wherein- Figure l isf a vertical; central,.crossgsectional-view of a preferred form of the inventionshowingthe same as applied tofl a drilling string. and illustrating the manner in which-thesame operates in awell boreas astabilizer;A

Figurezlis cross-sectionalrview, taken alongthe line 2 2: of. Figure 1flookin'g in the direction indicated by theV arrows; j

Figure 3 isarview similar to thatl of Figure 2fillustrating one.way inl which the invention may be operated to enlarge a-y key seat in a well bore; p

Figure: 4fis a-,viewsirnilar` to that of Figure-1, Yillustrating-{amodified-` formy of the invention;

Figure 5 ist` a cross-sectionalview, ltaken` alongf the line S-S of Figure 4, looking in the direction indicated by the arrows;

Figure 6 is a side velevationalV view, partly'broken-y away and partly in crosssectiong/of theformY` of theinvention illustrated insFigure-` 4, showing the relationship'of the parts whenthe device is-in condition to 'perform'areaming operation; and

Figure .7.Ais a view similarto'that caf-FigureV lillustrating a= different formof the invention.

Referring; now to-the drawings in' greater detail, the invention; as illustrated in `Figures -1, 2,V and 3, comprises anrouter tubular casingl, through which an inner tubular mandrel 12r extends, the mandrel, being providedV atY its upper 1 end =with aninternally threaded' rbox portion'. 14, lfor the-connection thereto of the lowersendlofan upper secti-oni16,lof a drilling string, and ybeingv externallythreaded atsits lowerl end,as indicatedzat` 18,A for the connection thereto` ofa-,couplingfelement 29, by whichthemandrel may be connected to the upper end ofalowersection'ZZ, ofthe drilling string, or toa drill collar orv other device locatedbelow the mandrel.

The mandrel. may be.' provided'l with` longitudinally' spaced sets of `"radially extending Vexternal te'e'thor splines, 24 and 26, and the casing 10 has internalradilly extending teeth or splines 28, located mediate its ends, which-are adapted to be intermeshed with either of the sets of external teeth 24 and 26, or whichmay occupy a position between the sets of teeth and out of Aengagement therewith.

The mandrel 12 is of substantially smaller external 'diameter than the internal diameter of the casing 10, whereby the mandrel will be spaced radially inwardly from the casing, and the casing is preferably provided at its ends with internal counterbores 30, forming packing glands, within which suitable packing, such as that indicated at 32 is disposed, to form a uid tight seal between the interior of the casing and the exterior of the mandrel. The ends of the casing are also internally threaded, as indicated at 34, for the reception of suitable screw plugs 36, which are engageable with thev packing 32 to maintain the same in sealing engagement with the mandrel and casing.

The mandrel 12 is of substantially greater length than i the casing 10, so that the mandrel may be moved upwardly or downwardly in the casing to engage or disengage the external teeth 24 or 26 with the internal teeth 28 of the casing. Within the casing, surrounding the mandrel 12, resilient elements 38 and 40, such as coiled springs, may be provided, which bear 'at their inner ends on suitable bearings, such as the ball bearings indicated at 42 and 44, respectively, and whose outer ends bear against suitable spring plates 46, seated in the counterbores 30, whereby the casing 10 is normally maintained with its internal teeth 28 out of engagement with the external teeth 24 and 26 of the mandrel. The bearings 42 and 44 are of conventional construction and of a size to provide clearance for the passage of liquid within the casing past the bearings, whereby when the interior of the casing is filled with liquid the inner and outer parts of the structure may be moved longitudinally yrelative to each other, without substantial resistance by with one or more openings 50, in which balls 52 are positioned, for engagement in an annular raceway 54 in theouter surface of the mandrel, the balls being urged inwardly toward the mandrel by coil springs 56, which are retained in position by screw plugs 58 closing the openings.

The interior of the casing betweenv the packing elements 32 within the counterbores 30 is adapted to be completely lled with a suitable liquid, such as oil, whereby the entrance of foreign material from the well bore into the interior of the casing is prevented.

In making use of the invention, constructed as described above, the mandrel 12 is connected into the drilling string, in the manner illustrated in Figure l, with the casing 10 located substantially centrally longitudinally of the mandrel, in which position the teeth 24 and 26 of the mandrel will be out of engagement with the internal teeth of the casing. The device is then lowered into the well bore, indicated at W, whereupon the drilling string will be guided in the well bore, and held out of contact with the wall of the bore by the engagement of the cutters 48 with the wall of the bore. In this condition of the apparatus it will be evident that the casing and mandrel may rotate freely relative to each other, so that the device operates as a guide and stabilizer to promote the drilling of the well in a straight line, y

well bore,such as that indicated -at K in Figure 3, of the drawings, the drill collar will be guided past the key seat and prevented from entering the same by the engagement of the cutters 48 with the wall of the key seat, whereby the drill collar will be prevented from becoming stuck in the key seat.

Under some circumstances, it may be desirable to rotate the casing with the mandrel to perform a reaming operation, as when the device becomes stuck in a key seat, or encounters some other yobstruction in the well bore. In this event, upon engagement of the cutters 48 in the key seat, or with the obstruction, the casing will be held against longitudinal movement in the well bore, and by raising or lowering the drilling string the mandrel 12 may be moved longitudinally relative to the casing to bring the teeth 24 or 26 of the mandrel into meshing engagement with the internal teeth 28 of the casing, whereupon the casing will be caused to rotate with the mandrel to ream out the key seat or obstruction. By suitably regulating the length of the mandrel 12 the relative longitudinal movement between the mandrel and the casing may be limited, so that the casing will be in engagement with the box portion 14 of the mandrel when the teeth 26 are in meshing engagement with the teeth 28, and the casing will be in engagement with the coupling element 20 when the teeth 24 are in meshing engagement with the teeth 28.

It will be apparent that the mandrel 12 may be moved either upwardly or downwardly relative to the casing to couple the casing to the mandrel for rotation therewith, so that the device may be employed for reaming upwardly or downwardly, as may be necessary or desirable.

Should the casing 10 become stuck in the well bore the drilling string may be operated to perform la jarring action thereon. This may be accomplished by moving the string upwardly with the external teeth 26 of the mandrel, and the internal teeth 28 of the casing positioned for endwise abutting engagement. When the teeth 26 and 28 are thus engaged, an upward pull may be exerted on the string to place the string under tension and the string may then be rotated in either direction until the teeth 26 ride off of the teeth 28, whereupon the mandrel will move upwardly relative to the casing to engage the coupling element 20 with the lower end of the casing to produce an upward jar on the casing. Similarly, the string may be moved downwardly with the teeth 24 of the mandrel and teeth 28 of the'casing positioned for endwise abutment until the string has been placed under compression, whereupon the string may be rotated to cause the teeth 24 to ride oi of teeth 28, and the mandrel will then move downwardly to engage box 14 with the upper end of the casing to produce a downward jarring action on the casing.

By upward or downward movement of the drilling string the casing may also be engaged with the coupling element 20 or with the box portion 14 to produce a jarring action on the casing to release the same in the event of sticking of the casing in a key seat or other obstruction in the well bore.

It will thus be seen that the invention, as described above, combines a drill pipe stabilizer and guide bushing, which is simple in construction, and wherein the parts of the mechanism are entirely enclosed and protected against abrasion or other injury, and which is also operable when desired, by manipulation of the drilling string to perform both teaming and jarring operations.

A modied form of the invention is illustrated in Figures 4, 5, and 6, wherein the mandrel 12' has only one set of external teeth 26' arranged for meshing engagement with the internal teeth 28' of the casing 10', and only a single coil vspring 38 is provided, which is located to coact with the mandrel and casing to yieldingly urge the casing upwardly on the mandrel to a position in which the teeth 26' and 28' are out of engagement, as

seen in Figure 4. The spring 38' bears at its upper end against the spring plate 40 and at its lower end against an external enlargement 6G formed on the mandrel. Bearing means, such as the b`all bearings indicated at 62 may also be provided, which are positioned on the lower plate 46'. In other respects the parts of this form of the invention are similar to those previously described in connection with the form of the invention illustrated in Figure l.

This form of the invention is used in a manner similar to that previously described, -the mandrel l2 being connected to the lower end of an upper section 16 of the `drilling string and to the upper end of a dlower section of'the same.

During the drilling operation, the parts will be in -the 4posit-ions indicated in Figure 4, Vthe teeth 26' and 28' being out of engagement and the casing 10 being freely rotatable on the mandrel to A'act as a stabilizer. Upon upward 0movement of the string, as when the drill is being `withdrawn from the well bore, should a key seat lor yother obstruction be encountered bythe casing 10', the

string maybe moved upwardly relative to the casing, compressing spring y3S' and bringing the teeth 26' and .28l into yintermeshing engagement, asshown in Figure 6,

whereupon the casing may be rotated with the string to effect a reaming action.

If desired a jarring action may be carried out with this 'form of the invention by moving the string longitudinally relative kto the-casingwith the teeth `2`6-and `28 in position for endwise abutment, whereupon the string may lbe placed under tension land upon rotation of the string the teeth 26 may be caused to ride olf of the teeth -28' so that the mandrel will be moved relative to the `casing Ito effect a jarring action thereon. l

A still diterent form-ofthe invention is illustrated lin Figure 7, which is somewhat similar in construction to that il-lustrated in Figures 4, 5, and 6, but wherein the pressure of iluid in the drilling string is utilized to operate the device. In this form of the invention the man* drel 12" has an upper portion 66 which is of smaller diameter than the lower portion 68 thereof, and an opening 7i) is provided, which leads from the interior of the mandrel and opens into the interior of the casing 10." By this means it will be evident that the cross-sectional area of the space Within the casing 10 at its upper end will be greater than the cross-sectional area within the casing at its lower end, and by the introduction of iiuid under pressure into the casing from the string through the opening 7d, the casing will be caused to move upward-ly on the mandrel to a position in which the teeth 26 and 28" are disengaged.

In making use of the form of the invention illustrated in Figure 7, the device is connected into the string in the same manner as the forms of the invention previously described and the pressure of fluid in the string during normal drilling operation will enter the casing 10 through opening 70 and maintain the parts in the condition shown in Figure 7, whereby the mandrel may rotate freely in the casing.

In the event of sticking of the casing in the well bore, it be desired to couple the casing to the mandrel for rotation therewith to perform a reaming operation, the pressure of iiuid in the string may be reduced, whereupon the mandrel may be moved upwardly relative to the lcasing to bring the teeth 26" into intermeshing engagement with the teeth 28 to cause the casing to be rotated with the mandrel. This form of the invention may also be operated in the manner previously described to etect va jarring action on the casing when desired.

The invention has been described herein in connection with a specific embodiment of the same, but it will be understood that this is intended by way of illustration only, and that numerous changes can be made in the l construction and arrangement of the various parts, with- 6 out departing from the spirit of the invention, or the scope of the appended claims. i

Having thus clearly shown and described 'the invention, what is claimed as new and desired to secure by Letters Patent is:

l. A device of the character described comprising inner and outer tubular parts movable longitudinally relative to each other, means for connecting the inne'rpart to an operating string, means positioned between and engageable with the parts to hold the inner part in radially inwardly spaced relation to the outerpart to form an annular chamber between the parts, sealing means between the parts at the ends of said chamber, abutment means on the inner part located exteriorly of the `outer part in position for `engagement with the ends ofthe outer part upon relative longitudinal lmovement of the `parts in either direction to limit such movement, yieldable means in said chamber positioned to coact with the parts to yieldingly hold the outer part in a centralized position between said abutment means, interengageable means on 'the parts in the chamberpositioned to be out of engagement when said outer part is in said centralized position to permit relative rotation of the Vparts and to bein engagement when said outer lpart is out of said centralized position in either direction to hold the parts vagainst relative rotation and means-on said youter part shaped to en- -gage the surrounding w'all of a well bore to hold said kpart to an `operating string, means positioned between and -engageable with the parts to holdthe inner part .in radially inwardly spaced relation to the outer part to form an 'annular chamber between the parts, sealing means between the parts at the ends of said chamber, abutment means on the inner part located exteriorly of the outer part in position for engagement with the ends of the outer part upon relative longitudinal movement of the parts in either direction to limit such movement, yieldable means positioned for engagement with the parts in said chamber to yieldingly hold the parts in a central position longitudinally relative to each other, interengageable means on the parts in the chamber positioned for engagement upon relative longitudinal movement of the parts in either direction from said central position to hold the parts against relative rotation and for disengagement when the parts are in said central position to permit such relative rotation and external means on said outer part positioned to engage the surrounding wall of a Well bore to hold the outer part centralized in said bore.

3. A device of the character described comprising inner and outer tubular parts movable longitudinally relative to each other, means positioned between and engageable with the parts to hold the inner part in radially inwardly spaced relation to the outer part to form an annular chamber between the parts, sealing means between the parts at the ends of said chamber, interengageable means on the parts in the chamber positioned for disengagement upon relative longitudinal movement of the parts to one position to permit relative rotation of the parts and for engagement upon relative longitudinal movement of the parts to another position to hold the parts against such relative rotation, yieldable means in the chamber positioned to coact with the parts to yieldingly hold the parts against relative longitudinal movement from said one to said other of said positions and radially extending external cutting means on said outer part whose outer ends are shaped to engage the surrounding wall of a well bore to hold said outer part centralized in said bore, said cutting means being shaped to enter a keyseat in said bore and to perform a cutting action on the wall of the bore in said keyseat upon rotation of said outer part in said keyseat.

4. A device of the character described comprising inner and outer tubular parts movable longitudinally relative to each other, means positioned between and engageable with the parts to hold the inner part in radially inwardly spaced relation to the outer part to form an annular chamber between the parts, sealing means between the parts at the ends of said chamber, interengageable means on the parts in the chamber positioned for movement to a disengaged position upon relative longitudinal movement of the parts to one position to permit relative rotation of the parts and to an engaged position upon relative longitudinal movement of the parts to another position to hold the parts against relative rotation, yieldable means in the chamber positioned to coact with the parts to yieldingly hold the parts against relative longitudinal movement in a direction to move said interengageable means from said disengaged position to said engaged position and external means on said outer part positioned to engage the surrounding wall of a well bore to hold said outer part centralized in said bore.

5. A device of the character described comprising inner and outer tubular parts movable longitudinally relative to each other, means positioned between and engageable with the parts to hold the inner part in radially inwardly spaced relation to the outer part to form an annular chamber between the parts, sealing means between the parts at the ends of the chamber, interengageable means on the parts in the chamber positioned for movement to an engaged position upon relative longitudinal movement of the parts to one position to hold the parts against relative rotation and to a disengaged position upon relative longitudinal movement of the parts to another position to permit relative rotation of the parts, yieldable means in the chamber positioned to coact with the parts to yieldingly hold the parts against relative longitudinal movement in a direction to move said interengageable means from said disengaged to said engaged position and external radially extending cutter means on said outer part positioned to engage the surrounding wall of a well bore to hold said outer part centralized in the bore and shaped to enter a keyseat in said bore and to perform a cutting action on the wall of the bore in the keyseat upon rotation of the outer part in the keyseat.

6. A device of the character described comprising inner and outer tubular parts movable longitudinally relative to each other, means positioned between and engageable with the parts to hold the inner part in radially inwardly spaced relation to the outer part to form an annular chamber between the parts, sealing means between the parts at the ends of the chamber, yieldable means in the chamber positioned to coact with the parts to yieldingly urge the parts toward a predetermined longitudinal position relative to each other, interengageable means on the parts in the chamber positioned to be engaged upon relative longitudinal movement of the parts away from said predetermined position to hold the parts against relative rotation and to be disengaged upon relative longitudinal movement of the parts into said predetermined position to permit relative rotation of the parts and external means on said outer part positioned to engage the surrounding wall of a well bore to hold the outer part centralized in said bore.

References Cited in the le of this patent UNITED STATES PATENTS 1,889,283 Francis Nov. 29, 1932 2,072,320 Thomas Mar. 2, 1937 2,538,690 Johnston Jan. 16, 1951 2,620,164 Burris Dec. 2, 1952

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1889283 *Apr 23, 1931Nov 29, 1932Arthur Francis JohnRotary jar
US2072320 *Dec 19, 1934Mar 2, 1937Thomas Charles EBit guide
US2538690 *May 24, 1948Jan 16, 1951Johnston James LCombination safety joint, bumper sub, and equalizing valve
US2620164 *May 15, 1948Dec 2, 1952Burris Joseph JKey seat wiper
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2994389 *Jun 7, 1957Aug 1, 1961Le Bus Royalty CompanyCombined drilling and reaming apparatus
US3136377 *Oct 9, 1961Jun 9, 1964Sandvikens Jernverks AbGuiding device for percussion drills
US3151690 *Mar 17, 1961Oct 6, 1964Gas Drilling Service CoWell drilling apparatus
US3316987 *Dec 10, 1964May 2, 1967Mcmanus Jr James HSelf-cleaning drill string tool
US3431990 *Feb 2, 1967Mar 11, 1969Houston Eng IncKeyseat wiper
US3472326 *Feb 5, 1968Oct 14, 1969Downen Jim LFishing tool energizer
US3999618 *Jan 22, 1975Dec 28, 1976Smith International, Inc.Hammer stabilizer
US4253531 *Oct 17, 1979Mar 3, 1981Boros Ladislav JSelf-balancing vibratory drill apparatus
US4452313 *Apr 21, 1982Jun 5, 1984Halliburton CompanyCirculation valve
US4476943 *Dec 29, 1981Oct 16, 1984Coal Industry (Patents) LimitedDrilling equipment with adaptor for steering long boreholes
US4727944 *Nov 26, 1986Mar 1, 1988Bottoms Clifford CPercussion drill string assembly
US5261498 *Jun 29, 1990Nov 16, 1993The Red Baron (Oil Tools Rental) LimitedDrill string component
US7234544Jun 28, 2004Jun 26, 2007Halliburton Energy Services, Inc.Drill tool shaft-to-housing locking device
DE1169387B *Dec 2, 1960May 6, 1964Wladimir TiraspolskyVorrichtung zum Fuehren eines Bohrwerkzeuges
EP0323772A1 *Dec 8, 1988Jul 12, 1989Institut Francais Du PetroleDrill string stabilizer with a clutch for rotation
EP1162344A1 *Mar 16, 2001Dec 12, 2001Offshore Rentals LimitedFriction reducing drillstring component
WO1991000411A1 *Jun 29, 1990Dec 30, 1990Red Baron Oil Tools RentalDrill string component
Classifications
U.S. Classification175/295, 175/300, 175/299, 175/321, 175/325.3
International ClassificationE21B17/10, E21B7/08, E21B7/04, E21B17/00
Cooperative ClassificationE21B17/1064
European ClassificationE21B17/10R3