US2506799A

US2506799A - Casing whipstock

Info

Publication number: US2506799A
Application number: US573865A
Authority: US
Inventors: Herman G Livingston
Original assignee: Eastman Oil Well Survey Co
Current assignee: Eastman Oil Well Survey Co
Priority date: 1945-01-22
Filing date: 1945-01-22
Publication date: 1950-05-09
Anticipated expiration: 1967-05-09

Description

May 9, 1950 H. G. LIVINGSTON 2,506,799

CASING WHIPSTOCK Filed Jan. 22, 1945 2 Sheets-Sheet 1 Herma/2 fri/@Stom lv INVENTOR.

Patented May 9, 1950 UNITED STATESy PATENT (l-FFICIEIr CASING WHIPSTOCK Herman G. Livingston; Houston, Tex.,v assignor, v by direct and mesne; assignments, to Eastman Oil Well Survey Company, Dallas, Tex., and', Denvfer, Colo., acorporation of Delaware.

Application J anuaryZZ, 1945,SerialNo. 573,865V

12 Claims. (Cl. Z55-1.6)

1V, This invention relates tonew and'I useful' improvements in casing Whipstocksl.

As is well known` acasingwhipstock is adaptedto be set within a. wellv casing .or pipe and is uti lized to. deflect or guidea drill-'bit outwardly into the formation at. an angle from-the main vwell bore. Prior to any offset. drillingoperation from a cased well/bore it is first.- necessary to out or mill. a window or opening in the` casing immediately. opposite thewhipstock face. to provide an open..

ing through which the. drill. maysubsequently. pass outwardly into therformation.. Milling tools.v

for performing-this milling operation are ingen eral use andisuccessfully cut the rst half or upper portion of the window; however, when ther center: line oi the milling tool reaches the center line of,

the wall oi the casing, there is a tendency for thek milling tool to jump out'intorthe formation beyond the oasingsince-said tool will naturallyV follow the line of least resistance. In-'other words.

as soon as the opening in the casing is-sufciently large to permit passage-oi themillingitool therethrough, said tool will move outfintorthe forma. tion instead `of continuing the milling oi said` window. This results in kthewindowf-or opening,l being incomplete, that is,` said window does not extend the full length of the longitudinal deflect-w ing face of `the whipstock, whereby' subsequent. attempts to properly drill off of the-whipstock.

are interfered with.

It is one object offthisinvention toV provide an improved casing Whipstock whiohis so constructed that a lsatisfactory elongatel windowl or.'` opening may be cut in the well casing after said'.

v/hipstock has been ysettherein.

An important object of the inventionxis to provide an improved casingwhipstock adapted to be set within a, welllcasing and havingits de-y lil fleeting surface movable longitudinally withinV said casing after the device is. ina set position,

manipulated to assure milling of a window which extends substantially throughout the lengthen.

the deflecting surface ofV said, whipstock.

Another object of the'inventionis tor provide an improved casing whipstock havinga .body

portion arrangedto be set' withinthe well cas.

-40 whereby said deflecting-surface .may be properly'.

ing and havingv a deilectingfelement attached` to and movable relative to saidloody,` whereby .when

the device is in a set position,1the delecting .ele' ment may oe in a loweredposition anda .window-f or opening; opposite the-,upper half'o the'defleeting. element may be milled; the construction; permitting raising of .the deecting. element after z' said. opening is milled, whereby saidyelement .is

moved into apposition locating the lower poI-,A tion of said deecting element oppositesad` previously formedfopening to permit a subsequentv milling Loperation to be .successfully-v carried out to complete a window or opening extending throughout thev entire length of the deflecting element.

Still another object -of the inventionl is to provide an improved casing Whipstock, of the character described, lwherein the dei'lectingelement is-,arrangedato ,be locked in a, raised or lifted posi.- l

tion; Wherebyzafter. the; milling; operation fis -complete, saidgdeflecting elementgprovides a rigid surface for guiding the ,subsequent drilling operation.

A still furtherxobjectoftheinvention is to.

provide an. improved casing whipstock, of the character described, having an improved4 lifting tool whichisarrangedto co-act withsaid whipstocl; to. eiectfliitingior raising Aoi the deflecting element' of said 'Whipstocki after theinitial millingoperation isvcompleted;` said, lifting tool permitting manipulation of thedeecting element with-v out removal. .ofv the whipstock from its set position.

The constructionfdesigned to carry out the invention will be l hereinafter described together with other.y features of the. invention.

The invention willv bemorereadily understood ironia reading of the following specification and by reference tov the. accompanying drawing, wherein an example-oiA the inventionV isv shown, and wherein:

Figurer-.1 is "a View partly insection and partly VVin. elevation. and illustrating a casing whipstock,

constructed in accordanoefwith the invention and set within. awell casing,V

Figure 2is a similarfview showing the rst millt img operation'Whichiiforms aV portion of the window in the well casing,v

Figuref-is anenlarged, horizontal, sectional. `view takenonthe lineii--tlA of.V Figure 5,

Figure 9 is a partial isometric view of the latching means for locking the deecting element of the whipstock in a raised position,

Figure 10 is a longitudinal, sectional View of the lifting tool which is utilized to raise the deflecting element of the whipstock,

Figure 11 is an enlarged, horizontal, cross-sectional view taken on the line I I I of Figure 10,

Figure 12 is a sectional detail illustrating the lifting arm of the lifting tool in a retracted or disengaged position, and,

Figure 13 is an isometric view of the lifting arm and its connection with the operating rod.

In the drawings the numeral I designates a well casing which extends through a well bore in the usual manner. A casing whipstock A is arranged to be lowered through the well casing and set at a desired position therein and when so set will serve to guide tools which are moved downwardly through the bore into engagement with the whipstock outwardly at an angle from the main well bore in the usual manner. The whipstock includes a body II which may be of any desired construction. The particular body illustrated is one now in general use and said body includes outwardly movable locking pins l2 which are arranged to be forced into engagement with the casing to lock the body in position therein. Outward movement of the pins is effected by a tapered mandrel I3 which has its upper end secured to a pressure-actuated piston I4, the latter being actuated by pumping pressure fluid downwardly through the casing. As noted, this type of casing whipstock body together with the particular locking arrangement forms no part of the present invention and any suitable body having means for locking the whipstock within the casing may be employed.

It has been the usual practice to attach a deecting element which is merely a wedge shaped member to the whipstock body II by a pivotal connection and in such case the deecting member and body portion comprise a single unit with said deecting element capable of a limited swinging movement with respect to the body.

In carrying out the present invention an elongate shank or extension I has its lower end threaded or otherwise fastened to the upper end of the body II and this shank is in axial alignment with said body and projects upwardly therefrom. The shank is provided with an axial bore I6 to permit fluid pressure to pass downwardly to the whipstock body to actuate the locking pins. If pressure-actuated locking pins are not employed, the shank could be solid in cross-section. An enlarged circular head |'I is made integral with the upper end of said shank, as is clearly shown in Figures 5 and 6 and the provision of said head I'I forms an annular shoulder I8 at the intersection of the shank and head.

A wedge shaped deflecting element I9, having an inclined guide surface 20 which tapers to substantially a point at its upper end, is provided with an elongate tubular body or sleeve 2| which is connected thereto by a pivotal connection I9a. As is clearly shown in Figures 5 and 6 the sleeve 2| has a bore 22 within which the head I'I of the shank I5 is slidable. The extreme lower end of the bore 22 of the sleeve is reduced as shown at 23, whereby an internal annular shoulder 24 is formed within said sleeve and the reduced portion 23 of the bore 22 is square in cross-section so as to substantially lit the square external surface of the shank I5. As explained, the head I'l has a sliding nt within the bore 22 of the sleeve 2| and said head is provided with an annular packing ring 25 which is located near its upper end, said packing sealing off between the head and the bore 22. The upper end of the sleeve bore 22 is closed except for a port or opening 26 which registers with the axial bore I6 of the shank.

Normally the delecting element I3 has its sleeve 2| are in a lowered position with respect to the body portion I I of the whipstock, as shown in Figure 5 and the parts are held in this position by means of a shear pin 21 which extends through the lower portion of the sleeve and which has its inner end connected to the shank i5. When upward pull is exerted upon the deecting member I9, upward movement of the body portion of the whipstock I I is prevented by the locking pins I2 which are engaged with the casing l0, whereby such upward pull will shear the pin 2'I. When this occurs a continued lifting of the deilecting member |9 will cause the sleeve to slide upwardly on the shank I5 until the internal shoulder 24 within the lower end of the sleeve strikes the external shoulder I8 formed by the underside of the enlarged head I1 (Figure 6).

For latching the sleeve 2| and the deilecting element connected therewith in a raised or lifted position with respect to the body of the whipstock, the head Il has a spring-pressed latch member 28 pivotally mounted on a, pin 29. As is clearly shown in Figures 7 to 9 the latch 28 is arcuate in shape and is normally disposed within an arcuate recess 3E] formed in the head I1. A flat spring 3| constantly urges the latch member outwardly so that said latch member engages the wall of the bore 22 of the sleeve 2 I. As the sleeve 2| is lifted after shearing of the pin 27 and said sleeve moves into the position shown in Figure 6, an arcuate slot 2 Ia which extends through the wall of the sleeve 2| near its lower end moves opposite the spring-pressed latch 28 so that said latch swings outwardly into this slot (Figure 7) It is apparent that when the latch is engaged within the slot 2 |a that further movement of the sleeve 2| with respect to the shank I5 is prevented. Thus, the deecting element |9 and its sleeve 2| will be locked or latched in a raised position with respect to the body portion II of the whipstock, as is clearly shown in Figures 3, 4 and 6.

For effecting a lifting or raising of the deilccting element I9 to its upper position, a suitable lifting tool which is shown in Figures l0 to 13 is provided. This tool includes an elongate body 32 which is generally tapered so that it may be lowered into the Well casing I in a position opposite the inclined guide surface 20 of the deflecting element I9. The body has a longitudinally extending surface 32a which conforms to the contour of the inclined surface 2B of the deecting element I9 so as to fit against said surface (Figure 1l) and it is these complementary surfaces which co-act to orient the body with respect to the deflecting element when said body is lowered into position adjacent said element. The body 32 has its upper end connected by a sub 33 to a tubular drill pipe 34 which is utilized to lower said body into position. The upper portion of the body 32 is drilled out to form a cylinder 35 and the diameter of this cylinder is substantially the same as the diameter of the boi'e of the sub 33 and is slightly larger than the bore of the drill pipe 34. Below the cylinder 35 an axial reduced bore 36 is provided and this bore extends from the lower end of the cylinder to a transversely extending slot 31. which. as. shown, ingFigure; 1Q is:l cut transversely through the mais: body- 3.2.-

Aff piston 38- isl .Slidablewithiu the Cylinder 35 andhas a piston rod 39. projecting. downwardly therefrom and through the reduced; bore S6 of the body 32 and the lower end of saidorodextends into thetransv-erse slot 3fIIj.v A.c o.il springvil nor-.- mollyuijges the piston 3 3v to a. raised position. within itscylinder. 3.5J The.j lower end; of therod 3.9 isr arranged. to actuate a lifting arlmJI whichl arm has one end pivote@ n e. Pin.- 42 which iS mountedin the body.. 'Ifhe lower endI ot. therod 3,9 is pivoted to the. upper end of a link 4.3. by a pin 4E. rlhe lower portionofjthelink.. extends into aflongitudinal slot 45 formed in the upper end of the, actuatingarmAI. (Figur-cl3.) Afcongnesting pin 46. extends.. transversely through. the lower end` of theconnecting., link 43. and hasits ends engaged. in longtudinalislots aIlg'provided in the` side` wallsl of. the. lifting arm LI. With this arrangement it will'. be apparent that vertical. 0.1'. longitudinal reciprocation. offthe, rod YSi 9 .will-.result in aswingingof thelitingarm Il I` orritspivot 42.

As explainedv theL pstonf38j is normally in. a raised position. being heldfsoby thespring 110 and in this positionthe lifting armfil isin a retracted positionas sho'wn'in. Figure 1 2. The liftingtool, assembly. is. loweredinto the...vell casing I0 with the parts in such position and thebody 32 of said. assembly willmoveinto. apcsitionwiththe transversejslot. 3l alignedwitha transverse slot, or opening 48 which is formed in the. deflecting member I9, Proper orientationror positioning of the slot 31, in the body 32 with theslot d8 in the element iseffectediby the co-actingsurfaces 32d of the. body and thev surface 2S ofthe element. As illustrated in, Figure l0, the upper wallie of thesl'ot or opening d8. is substantially flat. When the lifting toolf assembly moves into. a position aligning the slot 3,1 in the body32. with. the slot or openingV 48' in the deflecting member,A a pressure fluid is pumpedv downwardly through the drill pipe 34 and this pressure is exerted against the piston` 38 to move said' piston tov ar loweredj position; such downward movement will',4 of course, be against theV tension vof the coi-l spring 40. As the piston 38 .moves'downwardly therod 39 is also moved downwardly wherebythelink 4.3; because of its particular connection with the lifting arm tI willcause a swinging of said arm to an extended or lowered position. rhis causes the end of the arm to swing inwardly into the slot oropening Sfof the deflecting; element le. It will be obviousthat subsequent liftingrof the assemblyv and body 32o while maintaining theY piston 38 in its loweredY position' Will-result inv the lifting arm @l engaging the flatv upper Wall- 119 of the slot llt and thereby lift' the deflecting member` I9. It is through the use of the lifting tool assemblythat anupward force is vexerted on the deilecting element IS sufficient to shear theV connecting pin 21 after the in issheared it is apparent that the lifting tool assembly will raise the sleeve 2 I} and the element I9 to its raised positionA so that the spring pressed latch Y2- 8`j may lock saidv sleeve in such raised position.

In the operation of the apparatus it has-been pointed out that difficulty is at present encountered in attempting to mill a window'or opening within a well casing when an angular drilling operationis tobe carried-outin a casedwellbore. The particular apparatus hereinbefore described is arranged to make possible themilling of a win.- dow or opening in the. well casing which extends substantially throughout the, length oftheqguido surface ofthe. deecting member t9...

11nusnathe essere/tus). the whip.Steele which iionsietf:l Ot thebedy sofi/ico Hy andthedeeiine element. t9.; with. its; Pivotally le12tfi11 ii Sleeved! is. lowered Withinthe wel1` casing. and. Set therein .by moving the-locking pins l-Zeutwardlr into. eIles/sermentI with; the casing; through.. the application. of` fluid` pressure. Atthis time the deecting elementy L9. and its sleeveis in. a ylowered position. with respect to the. body H.. beine; se.- curedin; such position byithe-shear-pin 2 1. After thetdevice issetjwithin'the well casing IllaI suitable milling toolgf is lowered withinv the casing on a rotatable drill. pipe. 5I. The milling tool strikes the,z incline/df guide surface 2U. of the de: fleeting. element and .guided outwardly into contact .with the. wall; ofthe well casina the drill pipe is rotated to rotate;r the mill'. an.l open?.-l ing-, indicated at B in FigureI 2, will be formedzby the milling tool. Asn explained themilling toolwill.v operate satisfactorily until the center line of said tool moves past the. center of the wallthickness ofV thewell. casing and when this occurs the millwill tendto move. out into the forma.-v tion because vsaid formation will form less resistance to itsmovement than will the metallic wall of the casing. Thusit has been-found; that-when the mill 50 reaches the-position shown in dotted; lines inFieure 2 ,further milling.- Of en. Opening'- cannot be accomplished. It is apparent that an opening of the size indicated at B` in Figure. 2 would not besulcient to;A permit y free` movement of aA drill bit outwardly into the formation be.-

- cause-theA lower edge B ofi said; open-ingle a considerable distance above the, base or` lower end of the guide4 surface,y 20- ofv the, deflecting; element. It is obviousthat the.- drilljbit would hang on the lipioimedl by that portion` ofthe casingextend ngfupwardly abovethe basei of the` guide, surface.

After vthe initial opening Bois formed, the millsuena the @mi 'pipe 57| are removed from the Well casing I0 and the lifting tool assembly shown in Figure 10. isf-lowered through the casing. This assembly ismoved downwardly with the lifting arm 4I in aretracted position (Figure. 12v) until theslot 311 in the body 32 is. alignedwith theslot 43y in the deflecting member I9. Whenthis position is reached a pressurefluid is` pumped downs wardly through the pipe-34; on which the body 32 is lowered and a pressure is applied to the piston 38 to move-saidl pistondownwardly. As has been described the` downward movement of` the piston 3.8 will swing the lifting arm III outwardly into the opening or slot 48v in the deflecting member. Theolifting tool assembly is then. raised so asftor engagefthe. arm 4I withtheilat upper wall 4.9. of

V thenslot 48 and continuedupward movement of the lifting tool assembly will result inexertingan upward pull on the deecting member I9 and its sleeve 2|. Suchfupward pull will shear the pin 21 whereby continued upward movement will slide the sleeve upwardly onthe shank I5 which. isattached to thebodyportion II of the whipstock..

As-.the sleeve-.2| moves to its raised. position the springy pressed latch 28 will engage or swing out,- wardly intothe arcuate slot. 3l formed in the. wall of the sleeve whereby'the, sleeve-2 Iv and deecting member I9 are. locked ina raised position. The length. of upward travel of the sleeve. 2l is determined byy the length. of the shank I5 and is suchras to locate the lowerv end of the, guidev surfacek 20 of .the deflecting member oppositethe lowerfend of the-openingB which was previously. formed by the rst milling operation. Thisposi tion o,f .the.device is clearlyillustratedinlligure 3.

After the deecting element is Y moved to a raised position the mill 50 is again lowered into the well casing l and as it strikes the upper end of the deilecting member it is moved outwardly into engagement with the casing to mill out an additional portion of said casing. It will be obvious that by means of the two milling operations an enlarged window or opening C which extends throughout the major portion of the guide surface is formed. This window will permit the free passage of a drill bit upon a subsequent drilling operation. The particular advantage of the opening or window C is that its lower end is in alignment with or slightly below the base of the guide surface 20 whereby there is no obstruction to the passage of the bit from said guide surface into the formation.

The apparatus is relatively simple in construction and involves the use of a deflecting member which is capable of an axial movement with respect to the body of the whipstock so that said element may undergo movement after the body is in a set or locked position within the well casing. By use of the movable deecting element it is possible to mill a portion of the window and then raise the element into a position so that its base is aligned with the bottom of that portion of the window which is milled on the first milling operation. The window is then completed by a second milling operation which cuts out an additional portion of the casing. As has been stated no diniculty is encountered in milling a section from the well casing provided that the center line of the mill may be held inside of the center line of the wall of the well casing. Thus, it might be said that under normal and usual practices the upper portion of a window, that is, a window opposite the upper portion of a wliipstock can be readily formed and through the use of the present apparatus the milling all takes place opposite such upper portion of the deecting member. The particular lifting tool which is illustrated has been found satisfactory but it is apparent that other types of lifting devices could be employed to raise the denecting member to its locked position after the initial milling operation. Therefore, the invention is not to be limited to the specic construction of the lifting tool which has been shown.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

1. A casing whipstock for use with a milling tool to permit said tool to make two contiguous openings in the casing including, a support having means for anchoring the same within a well casing, a deilecting element having an inclined guide surface mounted on the support and movable axially thereof to an extremerlower position for one milling operation and an extreme upper position relative to said support for a second milling operation, said element being normally in its lower position on said support, and co-acting means on said element and said support assuming operable engageable condition when the element is moved upwardly to its upper position to secure said element in such upper position to positively prevent subsequent lowering of said element with respect to the support.

2. A casing whipstock as set forth in claim 1,

8 together with additional co-acting stop means on the support and on said element for limiting movement of said element with respect to said support to locate the upper and lower positions of said element on the support.

3. A casing whipstocl: as set forth in claim 1, together with frangible means connecting the deecting element to the support in its normally lower position, said frangible means being adapted to be fractured by an upward pull on the deflecting element to permit movement of the element to its upper position, and also wherein the coacting means on said element and said support is a spring-actuated latch mechanism.

4. A casing whipstock including, a support, means for anchoring the support within a well casing, an upstanding shank extending axially from the support, a dei'lecting element having its lower portion slidable on the shank, said element being normally in a lowered position on said shank and being movable to a raised position whereby said element is spaced from the support.

5. A casing whipstock as set forth in claim 4, together with frangible means for fastening the element in a lowered position, said means being fractured by an upward pull on the element to permit raising of said element, and means for locking said element in its raised position.

6. A casing whipstock including, a body portion having means for anchoring the same within a well pipe, a deflecting member above the body and having a telescoping connection with said body portion, said member being normally in a lowered position supported on said body portion, whereby a deecting operation off of the deecting member may be accomplished with said member in its lowered position, the telescoping connection permitting the deflecting member to be raised with respect to the body portion to locate said member at a higher elevation and co-acting means carried by the body and member and capable of being brought into co-acting relationship when the member is raised to its higher elevation and thereby secure the member to the body and hold it in said higher elevation, whereby a subsequent deflecting operation may be carried out at said higher elevation.

'7. A casing whipstock as set forth in claim 6, together with a frangible means for connecting.' the deflecting member to the body portion with said member in its lowered position, fracturing of said frangible means being necessary to allow movement of the member to its raised position.

8. A casing whipstock as set forth in claim 6, wherein the co-acting means is a spring-pressed latch means for locking the deecting member in its raised position with respect to the body p0rtion.

9. A casing whipstock including, a body having means for anchoring the same within a well pipe, an upstanding shank on said body, a delecting member, a tubular extension on the lower portion of said member engaging over and being slidable on the shank, the member being normally in a lowered position with the lower end of the extension being supported on the upper end of the body, and latching means on the upper end of the shank adapted to co-act with means on said extension for latching the extension and deflecting member in a raised position when said extension and member are moved upwardly with respect to the body.

10. A casing whipstock as set forth in claim 9, wherein the co-acting latching means on said shank and said extension is a pivoted latch on 9 one element and an opening for receiving said latch on the other element.

11. A casing whipstock as set forth in claim 9, together with frangible means connecting the eX- tension and shank when said extension and deecting member are in their lowered position on the body, said frangible means being fractured by an upward pull lon said defiecting member to allow subsequent upward movement of the member with relation to the body.

12. A casing Whipstock including, a body having means for anchoring the same Within a Well pipe, an upstanding shank on said body, a deflecting member, a tubular extension on the lower portion of said member engaging over and being slidable on the shank, the member being normally in a lowered position with the lower end of the extension being supported on the upper end of the body, a pivoted latch member mounted in the upper end of the shank and movable outwardly thereof, resilient means engaging the latch member and constantly urging said member into contact with the inner wall of the extension, the lower end of the extension having an opening therein which opening moves into alignment with and receives the latching member when the extension is moved upwardly on the shank, whereby said extension is latched to the shank in its raised position.

HERMAN G. LIVINGSTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS