CA2025653A1 - Orientatable adjustable bent housing - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

An orientatable adjustable bent housing consisting of a tubular inner housing which is telescopically received within a tubular outer housing. A sleeve is provided which has an angular offset end face. The sleeve is axially slidable along the inner housing between a coupled position wherein spline non-rotatably couple the sleeve with the inner housing and an orientatable position wherein the sleeve is disengaged from the spline permitting respective rotational positioning of the sleeve and the inner housing. In the coupled position the sleeve is further slidable between an inoperative position wherein the sleeve is spaced from the outer housing and an operative position. In the operative position the angularly offset end face of the sleeve is brought in fare to face relation with an angularly offset end face of the outer housing thereby creating a bend the magnitude of which is dependent upon the relative rotational positioning of the outer housing and the inner housing. An overlapping splined engagement couples the inner housing to the outer housing when the sleeve is in the operative position. A locking nut maintains the sleeve in the operative position.

Description

The presell-t inverl-tion relates -to an or:ienta-table adjustable herlt housing.

~AC~GROUND OF THE INVENTIO~
Over -the last few year~ adj-ustable bent ho-usings have become we l 1 known in the oil industry in connection with the use of down}lole drill.ing mo-tors. Fo~ downhole drilling a number Qf components are u~ed in conjunc-tion with the downhole drilling motor. These componerl-t6 are 10 a drill bi-t a bearing a~sembly a drive shaft and a housing i~ whic}l the drive ~haft is housed. The downhole drilling mo-tor produces an eccer~tric mo-tio~.
The bearing as~embly absoIbs -the radial and thrust loadiny from the drill bit and drives the drill bit in a 15 CollCentric motion. The drive shaft is construe-ted with a universal joint type of connection to convert the eccentric mot:iorl of the drilling mo-tor into concerltric motion required by the bearing assembly. The drive shaft pa65e~ throuyh the housing which is secured at one 20 end to the drilling motor and at the other end to the bearing a~sembly.

In direGtional drilliny a bend i6 placed in the drill string in order to cause the borehole created by 25 the drilling process to deviate at an angle from the vertical. It is desirable to get this "bend" as close as possible to the drill bit this is accomplished by using a bent housing. It is however inconvenierlt to disas~emble the bearillg a6sembly drive shaf-t and 30 drilling motor in order to replace the bent housing with a different bent housing with a bend of a differeTlt magnitude. For this reason adju~table bent housings were developed. The magnitude of the bend in an 35 adju~-table bent hou~ing i8 adju~table by relative ro-tation of two ma-t.ing components. T~e curre~t ~tat'e of -the ar-t i5 reflected in Uni-ted States Patent 4,813,497 which isswed to ~enrleth H. ~enzel. !r 't) ~;
As the art of directional drillir1g progre~es, the prac-tice has developed of usirly an adju~table bent 8ub, in comb:ination with another bent sub positioned above the drilling motor. U~in~ two bent ~ub~ in this manner allows the borehole to be drilled at an greater angle in less time than would be pos~ible when using only one 0 bent 5Ub. A problem has arisen, however, .in ge-tting the bends in the two bent sub~ to alig~. A separate tool has beel1 developed which addresses this problem which i5 referred to as an orientation s~b. The U9~ of an orientatiorl sub add~ one more component to the dxilling 15 motor assembly which is viewed as undesirable.

S~MMA~Y OF_T~ IN~R~TION
What i5 required is an orientatable adjustable bent housing which will render the use of an orientation sub redundant.

According to the present invention there i5 provided an orientatable adjustable bent housing which is comprised of a tubular outer housing having a first 25 end, a second endj and an interior surface. The qecond end of the outer hollsing has an angularly offset end face. A tubular inner housiny is provided having a first end, a second end and an exterior surface. The irst end is telescopically rece;ved within the secorld 30 end of the outer housiny. A sleeve is provided having a Eirst end, a second end, an inter.ior surface and an exterior surface. The first end o-E the sleeve has an angularly ofEset end face. Surface engagement means are 35 provided for noIl-rot~tably coupling the interior surface of the sleeve with the exterior ~urface of the inner , ~:
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housirlg. The ~leeve is a~ially ~lidable alorlg the exterior ~urface of the inrler housing betweerl a coupled pVSi tiOIl wherein the ~leeve i5 no~ ro-tatably coupled by the surface engagemen-t means to -the inner housirlg and an orien-ta-table posi-tion whe~ein -the sleev~ i5 disengayed frQm the surface engagement means thereby permitting respec-tive rota-tioIIal posi-tionirlg of the sleeve and the inner housirlg. Irl the coupled posi-tion the ~leeve is further ~lidable between arl adju~table pos.itio~l wherein the first end of the sleeve i~ spaced from the second ~end of the outer hou~iny arld an operative position. In the operative position, the angularly offset end face a-t the firs-t elld of the sleeve i~ brought in face to ~ace relation with -the angularly offse-t end ~ace at the 15 s~cond end of the ou-ter housing thereby aliyning the inner housing and the outer housing in a bent position the maynitude of which is dependerlt upon -the relative rotational positioning of the outer housirlg and the inner hou~in0. The bend i5 orierrta-table by sliding the 20 sleeve to -the orientatable position. A first annular member projects from the exterior surface at the first end of the inner hou~ing. The firs-t annular member has a concave radiused contact surface. A second annular member projects from the interior surface at the secorld 25 end of the outer hou5iny. The second armular member has a convex radiused contact surface. The convex contact surface of the second anrlular member engages the concave contact surface of the first annular member thereby preventing axial separation of the inner housiny and the 30 outer housing while accommodating the bend created when the sleeve is in the o~erative position. An overlappiny splined engagemen-t between the e~terior surface at the first end of the sleeve and -the interior surEace at the 35 second end of the outer housing non-rotatably couples the inner housing with the outer housing when -the ~leeve ~ ~
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is in -the op~rative po~i-tlon. A locking n-u-t thr~eadedly engages th~ exterior surface of the inner--housirlg -to ~ecure the sleeve in the opera-tiv~ posit:ion.

B EF DESCRIPTION OF THE DRAWINBS
These and other feature~ of the inventiorl will become more apparen-t ~rom the followiny descrip-tion in which ref~rence is made to the appended drawings, whereirl:
FIGUR~S la a~d lb together corlstitute a longitudinal sectiorl view of a preferred embodiment of the inven-tion.
FIGURE 2 is a -transverse ~ection view taken along section lines 2-2 of FIGURE 1.
FIGUR~ 3 is a tran~verse section vi0w -taken along section lines 3-3 of FIGURE 1.
FIGUR~ 4 is a -transvers~ section view taken alony section lines 4-4 of FIGURE 1.

20 D~TAIL~D D~SCRIPTIO~ OF THE PR~RED ~BODIM~T
The preferred embodiment i~ an orientatable adjustable bent housing, generally referred to by reference numeral 10, which will now be described with reference -to FIGUR~ 1. The primary components of 25 orientatable adju~table bent housing 10 are a tubular outer housing 12, a tubular inner housing 14, a slee~e 16, and a locking nut 18.

Tubular outer housing 12 has a fir~t end 20, a 30 second end 22, an interior surface 24 and an exterior surface 26. First erld 20 has a -threaded conrlection, for connection to other tubular comporlents u~ed with a drilling motor. Second end 22 of outer housing 12 ha~
35 an angularly offse-t end face 28, the purpose of which will be hereinafter described.

~ 0 ~ 3 Twbular inrler housiny 14 has a f;rst end 30, ~econd end 32, and an e~terior sur~ace 3~. First end 30 of inner housing 14 i5 -tele~copically received within ~econd end 22 of outer housirlg 12. Second end 32 ha~ a th~eaded comlection, for connectiorl to other tubular components used with a drilling motor.

Sleeve :16 ha~ a first erld 36, a second end 38, an interior surface 40 and an exterior surface 42. Fir~t 10 end 36 of sleeve 16 has an angularly of fset end face 44.
Sleeve 16 iB longitudinally ~lidable on exterior surface 34 of inner housing 14 as will be hereinafter described.
In the embodiment illustrated, sleeve 16 has two co~nponents 16a and 16b. These componen-ts overlap and 16 are linked by a plurali-ty of ball bearings 46, as illustrated in FIGUR~ 4. Interior surface 40 of sleeve 16 has a ci~cumferential groove 41 adjacent second elld 38. Locking nut 18 has an excerior surface 43 with a circumferential g~oove 45 adjacent an end 47 opposite 2~ second end 38 of ~leeve 16. End 47 of lockiny nut 18 i~
tele~copically received by second ~nd 38 of sleeve 16.
In -this tele~copically engaged position circumferential groove 41 is opposite circumferential groove 45 forming a ball bearing race 49. Ball bearing~ 46 disposed in 25 the ball bearing race couple sleeve 16 and locking nut lB. A passage 48 e~tends throuyh sleeve 16 -to permit ball bearings 46 to be in erted. Passage 48 is closed af-ter insertiorl of ball bearing 46 by a plug 50.

Locking nut 18 ha~ a first end 52 and a second end 54. Locking nut 18 is threadedly engageable with exterior ~urface 34 of inner housing 14 as will be hereinafter described. Second end 52 of locking nw-t 18 35 i~ overlapped by ~econd end 38 of sleeve 16, ~nd ~leeve .
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2 ~ 3 16 i5 linked to locki.ng nu-t 18 by a plurality of ball bearings 46. A5 previously de~cribed, a pa~sage 48 extend~ through sleeve 16 to permit ball bearinys 46 to be inserted. Passage 48 is closed after inser-tiorl of ball bearing3 46 by a plug 50.

Referring to FICUR~ 3, surface enyagemeIlt means in th~ form of mating ~pline 56 and 58 non-rotatably couple 10 sleeve 16 with inner ho-using 14. Spline 56 depends from interior ~urface 40 of sleeve 16 and mating spline 58 iY
on exterior sur~ace 34 of inner housing 14. When splines 66 are engaged with splines 58, sleeve 16 is non-rotatably coupled with inner hou~ing 14.

There i5 also a splined engagement b~tween second end 22 of outer housing 12 and ~irst end 36 of sleeve 16. Second end 22 of outer hou~i~g 12 has a protruding collar portion 60 which overlaps a protruding tapered 20 neck portion 62 at first end 36 of sleeve 16. Referrirlg to FIGURE 2, on protru~ing collar ~ortion 60 int~rior surface 24 of outer housirlg 12 has deperlding spline 64 which engage mating spline 66 on ex-terior ~urface 42 of protruding neck portion 62 of sleeve 16.

The axia~ withdrawal of inner housing 14 from outer housing 12 i5 prevented by annular members ~8 and ~0.
First annular member 68 is secured to exterior surface 34 at first end 30 of inner housing 14. Second annular 30 wedge 70 i5 secured to in-terior surface 24 a-t second end 22 of outer housing 12. Second annular member 70 engages first annular member 68 to preverl-t axial movement of inner housing 14 ln relation to outer 3~ housiny 12. First annular member 68 and second annular : member 70 have mating radiused contact surfaces 72 and .;

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2 ~ 3 ~4, respec-tively. Corltac-t surface ~2 i~ concave, while co~tact surfa~ 74 is convex. First annular member 68 is part of an end cap 76 secured -to first end 30 of inner housing 14. Second an}lular member ~0 .is posi-tioned against a s~loulder 78 wh:ich protrud~s from interior ~urface 24 at .~econd end 22 of outer housing 12.

The use and operation of orien-tatable adjustable 10 bent housirlg will now be de~cribed with reference to FIG~RE 1. When orierltatable adjustable bent housing 10 is placed in position between the bearing assembly (not showll) and drilling motor (not ~howrl) a drive shaft 80 extends through orien-tatable acljustable bent housing 10.
15 Sleeve 16 is axially slidable along ex-terior surface 34 of inner housing 1~ between a coupled position and an orien-tatable posi-tion. In cthe Goupled positiorl sleeve 16 i~ non-rotatably coupled by the mating of spline 56 and 58 to inner housing 14. In the oriencatable 20 position Ypline 5~ of sle~ve 16 are disengaged from spline 58 of inner housirl~ 14 permitting respective rotational positioning of sleeve 16 and innQr housiny 14. In the coupled position sleeve 16 i8 further .~lidable between an adjustable position and an operative 25 position. In the adjustable position fir~t erld 36 of sleeve 16 is spaced from second end 22 of outer housing 12. In the adJustable position respective rotatiorlal adjustment can taken place between inner housing 14 and outer housing 12. In the operative posi-tion, anyularly 30 offset end face 44 at first end 36 of sleeve 16 is brought in face -to face relation with angularly offset end face 28 at secorld end 22 of oute~ hou~irlg 12 thereby creating a bend the magnitude of which is dependent upon 35 the relative rotational positioning of outer housing 12 and inner housing 14, .

~` 2~2~3 I-t will be seerl from the abuve descliptiorl o the positions o~ ~leeve 16, -that in the adju~table position ~leeve 16 i8 nofl-rota-tably coupled to insler housing 14 so that a respective rotation of inner housing 14 in rela-tion tu ou-te:r housirlg 12 will charlye the mating of angularly offset esld faces 28 and 44. IE the bent created by the ma-ting of arlgularly offse-t end faces 28 and 44 re~uires or:ientation, thi~ i8 accomplished by moving 61eeve 16 to the orienta-table position p~rllli-ttirlg 10 re~pec-tive rotation oE sleeve 16 and inner hou~ing 14 until the bend is orientated in the desired di:rec-tion.
Sleeve 16 can then be placed in the operative position Wi th the bend at the desired anyle and in the right direction. Sleeve 16 is main-tained in -the operative 5 po5ition by locking nut lB which engages exterior surface 34 of inner housirlg 14. In the operative posi-tion, inner housing 14 i5 non-rotatably coupled via sleeve 16 with outer housing 12~ to maintain the desired rota-tional posi-tioniny of inner housing 14 and outer 20 housing 12. The norl-rotational coupling i~ accomplished by a combination of mating spline 56 and 58 which non-rotationally couple sleeve 16 to inner housin~ 14; and mating spline 64 and 66 which non-rotationally couple sleeve 16 to outer housing 12.

It takes a ~pecial form of stop mean~ to accommodate the alteriny of the respective angular positioning of the ou-ter hou~iny 12 and the inner housing 14. However, with the mating annular members 68 30 and 70, whatever bent is created when slee~e 16 i5 secured in the operative po~ition can be accommodated by the radiused contact surEaces ~2 and 74 which can mate regardless of the angular po~ition a~sumed. Convex 3~ contact surface of secoIId amlular member enyages concave 2~2~

contact surface of first anrlulclr mer~l~er. T,~3e ac-tual poin-t of contact varies with -the bend creatcd. The radiu~ of the contac-t ~urfaces 72 and ~4 are prefer~bly takerl E.rom a centerp,int po~itiorled alorlg the mating o~
anyularly off~e-t erld aces 28 and 44.

In order to effect an angular adjust~ent of orientatable adju~table ben-t housing 10, lock:iny nut 18 must be "backed off" to perl~it sleeve 16 to be moved axially ~long in~er hou~ing 14. The presence of ball bearings 46 results in locking nut 18 being lin~ed with sleeve 16 such that ~5 locking nut 18 is loosened first end 36 of sleeve 16 is drawn away from second end 22 of outer hou5iny 12. Once sleeve 16 ha~ been drawn back 16 approximately 3/4 of an inch spline 64 dissngage ~pline 66 permittiny relative rotation between outer housing 12 and inrler housing 14. This relative rota-tion results in angularly offset end face 44 at first end 36 of sleeve 16 changing its position in relation to angular off~et 20 end ~ace 23 at second end ~2 c,f outer housiny 12 thereoy alterir,g the ~a~nitude to the bend in orientatable adjustable bent housing 10.

If it appears that it is ~ecess~ry to "orient" the 25 bend to correspond with a bent sub pcsitic,ned above -the drilling mo-tor, this i5 accomplished by sliding sleeve 16 further along e~terior surface 34 toward secorld end 32 of inner housing 14. As sleeve 16 moves toward second end 32 of inner housing 1~ it reaches a position 30 where it i~ no longer in the coupled positio~ as spline 56 disengage Mpline 58 permitting relative rotation o~
sleeve 16 and inner housing 14. Sleeve 1~ is then considered to be in an "orientatable" posi-tîon, 35 permitting the bend i~ orientated in a de~ired direction.

:: -- ~ , ,3~3 The necessary adjus-tllle~lt havir~g beerl sleeve 16 i~
slid along irlner housi~lg 14 until i-t is firstly in a coupled position, and therl upon further sl:idirlg of sleeve 16 is placed in an operative positio~. Loc~ing nut 18 is then tighterled unt:il sleeve 16 is tiyhtly secured in place with first erld 35 engaged by second end 22 of ou-ter housiny 12 and second end 38 engayed by first end 52 of locking IIUt 18.

It can be seen from arl e~amination of FIGURES 2 arld 3, that the splined engagemellt~ used have 48 tee-th which permit adjustment in 1/8 of a degree increments. This is a more refined adju6tment tharl is possible with marly prior art tools. Indicia i~ placed on the exterior of 15 orienta-table adjustable herlt hou~ g 10 to serve as a guide in making adjustments of the angle of the bend and the orientation.

It will be apparent to one skilled in the art that 20 the mating engagement of splines 64 and 66 at the overlapping of fir~t end 36 of sleeve 16 and second end 22 of inner housing 14 preclude~ the entry of clrilling fluid be-tween annularly o~se-t end faces 28 and 44, which over time can adversely effec-t the operatio~ of ~ 25 the tool.
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It will also be app~ren-t to one Ykilled in the art that the use of ball bearings ~6 to couple sleeve 16 and ; lockislg nut 18 resolves a problem in the art wi-th 30 respect to the use of sleeves. In the prior art the sleeves used were diEficul-t to move due to dried drilling fluids or corrosion. ~ften a hammer and chisel had to be us~d to de-tach sleeve 16 from inner housing 35 1~.

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2~25~3 It wi11 fina11y be apparent to une ~ki11ed in the art that modificatiorl~ can be made to the preferred embodimerl-t withou-t departing ~rom t~le pirit ~nd ~cupe of the inverl-tion.

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Claims (2)

1. An orientatable adjustable bent housing, comprising:
a. a tubular outer housing having a first end, a second end, and an interior surface, the second end of the outer housing having an angularly offset end face;
b. a tubular inner housing having a first end, a second end and an exterior surface, the first end being telescopically received within the second end of the outer housing;
c. a sleeve having a first end and a second end, an interior surface and an exterior surface, the first end of the sleeve having an angularly offset end face;
d. surface engagement means for non-rotatably coupling the interior surface of the sleeve with the exterior surface of the inner housing, the sleeve being axially slidable along the exterior surface of the inner housing between a coupled position wherein the sleeve is non-rotatably coupled by the surface engagement means to the inner housing and an orientatable position wherein the sleeve is disengaged from the surface engagement means thereby permitting respective rotational positioning of the sleeve and the inner housing, in the coupled position the sleeve being further slidable between an inoperative position wherein the first end of the sleeve is spaced from the second end of the outer housing and an operative position wherein the angularly offset end face at the first end of the sleeve is brought in face to face relation with the angularly offset end face at the second end of the outer housing thereby aligning the inner housing and the outer housing in a bent position the magnitude of which is dependent upon the relative rotational positioning of the outer housing and the inner housing, the bend being orientatable by sliding the sleeve to the orientatable position;

e. a first annular member projecting from the exterior surface at the first end of the inner housing, the first annular member having a concave radiused contact surface;
f. a second annular member projecting from the interior surface at the second end of the outer housing, the second annular member having a convex radiused contact surface, the convex contact surface of the second annular member engaging the concave contact surface of the first annular member thereby preventing axial separation of the inner housing and the outer housing while accommodating the bend created when the sleeve is in the operative position;
g. an overlapping splined engagement between the exterior surface at the first end of the sleeve and the interior surface at the second end of the outer housing thereby non-rotatably coupling the inner housing with the outer housing when the sleeve is in the operative position;
and h. a locking nut threadedly engageable with the exterior surface of the inner housing, 'he locking nut being adapted to secure the sleeve in the operative position.

2. The orientatable adjustable bent housing, one of the locking nut or sleeve having an interior surface with a circumferential groove, the other of the locking nut or sleeve having an exterior surface with a circumferential groove, the one with the circumferential groove on the exterior surface being telescopically received in the other having the circumferential groove on the interior surface such that the circumferential grooves are placed in opposed relation thereby forming a ball bearing race, a plurality of ball bearings being disposed in the ball bearing race thereby coupling the sleeve and the locking nut.