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Publication numberUS3095039 A
Publication typeGrant
Publication dateJun 25, 1963
Filing dateOct 7, 1960
Priority dateOct 7, 1960
Publication numberUS 3095039 A, US 3095039A, US-A-3095039, US3095039 A, US3095039A
InventorsKinzbach Robert B
Original AssigneeBowen Itco Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Whipstock and anchoring mechanism therefor
US 3095039 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

June 25, 1963 R. B. KlNzBAcH 3,095,039

wHIPsTocx AND ANcHoRING MECHANISM THEREFOR Filed Oct. 7, 1960 2 Sheets-Sheet 1 Foef/ /f/zaf INVENTOR.

ATTORNEY R. B. KxNzBAcH 3,095,039

2 sheets-sheet'z June 25, 1963 WHIPSTOCK AND ANCHORING MECHANISM THEREFOR Filed Oct. 7, 1960 y Ii-w`5 Vabove the casing seat.

3,095,039 STCK 'AND ANCHORING MECHANISM TIEREFR Robert B. Kinzbach, Houston, Tex., assigner to Bowen- Itco, Inc., Houston, Tex., a corporation of rIexas Filed Oct. 7, 1960, Ser. No. 61,111 5 Claims. (Cl. 166--117.6)

This invention relates to the drilling of wells and more particularly to drilling operations in which it is desired .to deflect the well bore.

The invention is capable of -application in connection with a variety of well drilling operations, such as sidetracking, straightening crooked holes, establishing new drilling courses, work-over operations and directional drilling, and .inds particular utility in cased wells where it is necessary for a whipstock to be initially inserted without actuating the whipstock anchoring mechanism.

In the operation of oil and gas wells, the well bore is often provided with a casing which extends downwardly in the bore and terminates above the level of the producing lformation and .an inner liner of smaller diameter is positioned in 4the bore which extends downwardly below the casing seat or lower end ofthe casing to the desired depth, such inner liner sometimes terminating at its upper end Should it become necessary to cha-nge the angle of the bore, such as in a sidetracking operation, at some location along the length of the inner liner -in a well thus equipped, ya section of the liner may be cut .away to provide a space between the lower end of theupper portion of the liner and `the upper end of the lower portion thereof, thus provided, =at the desired dept-h, and a whipstock may be inserted into the lower portion of the liner with the upper end thereof extending upwardly in the bore in position to deflect the drilling bit.

The anchoring of a whipstock which is to be used in this manner is usually accomplished by means of slip mechanism which is designed to be actuated or placed in condition to be set .by means positioned for engagement with the upper end of the liner when the lower end -of the whipstock has entered the same.

When the liner is cut or milled away at the location where the whipstock is to be located, however, the posi- 'tioning and anchoring of a whipstock provided with `anchoring mechanism of the usual type becomes very diicult if not iin-possible due to the tendency of the slips to become set upon entry into the upper portion of the liner or casing.

In the present practice it is sometimes customary to use rope strand wound around the whipstock iat a location to temporarily hold the slip actuating mechanism in inactive position, the whipstock being .then lowered into the A liner or casing and Vthe rope being rubbed off by contact with the inner surface of the liner or casing so that when 4the whipstock passes out of the liner or casing at the location where a section has .been cut, .the slip .actuating mechanism will be in condition for actuation to anchor the whipstock in the upper end of the portion of the liner below.

The present invention has for an important object the provision of a whipstock having mechanism for anchoring the same in a well tubing and embodying means tor preventing actuation of the anchoring mechanism before the whipstock reaches the desired location.

Another object of the invention is to provide whipstock anchoring mechanism embodying means whereby such mechanism may be held in an inactive condition during the lowering of the whipstock through an upper section of a liner in a well .and thereafter released to allow the anchoring mechanism to assume a conditionto anchor the whipstock in a lower section of the liner when the whipstock enters the same.

3,695,639 Patented June 25, 1963 A lfurther object of-the invention is the provision in whipstock anchoring mechanism of the type having slips and actuating means therefor which is movable'into and out of an .active position for `engagement with the upper end of a lower section of a liner in a well to actu-ate the slips when the whipstock enters said lower section to anchor the whipstock therein, and including means for holding the actuating means out of said active position `and means for releasing said holding means when the whipstock enters an upper section of the liner whereby the lactuating means may move into such active position when the whipstock has passed through said upper section.

Another object of the invention is the provision in whipstock anchoring mechanism including slips and means for actuating the slips into gripping engagement with -a surrounding liner in a well upon downward movement of the whipstock relative to the slips, of movable meanson the mechanism connected to the slips :and movable into and out of a position for engagement with the upper end of a lower section of the liner .to hold the slips |against downward movement to. `allow the whipstock to move downwardly relative to the slips to expand the slips, releasable means ttor holding the actuating means out of said position to allow the whipstock to move through an upper section ofthe liner without becoming anchored therein, and means positioned `for engagement with said upper section to release said holding means to allow the actuating means to move into said position when the whipstock moves out of said upper section to position the actuating means for engagement with the upper end of said lower section to expand the slips upon -downward movement of the whipstock in said lower section.

The above and other important objects and advantages of the invention may best be understood from .the following detailed description of a preferred embodiment of the same, when considered in `conjunction with the annexed drawings, wherein- FIGURE 1 is a fragmentary, vertical, central, crosssectional view, on a reduced scale, illustrating somewhat diagrammatically a preferred embodiment of the invention .and .showing the same during one stage of the positioning of the whipstock mechanism in a well;

FIGURE 2 is a view similar to that of FIGURE 1, showing th-e whipstock in a more Iadvanced stage of the positioning of the same in the well;

FIGURE 3 is a View similar to that of FIGURE l, showing the whipstock in its anchored position in the well preliminary to the beginning of -a new drilling operation;

FIGURE 4 is a fragmentary, side elevational view of the whipstock of the invention .showing details of structure of the anchoring mechanism of the same, the anchoring mechanism being shown in its retracted condition;

FIGURE 5 is -a cross-sectional view, :taken along the line 5 5 of FIGURE 4, looking in the direction indicated by the arrows; and

FIGURE 6 is a cross-sectional view, taken along the line 6 6 of FIGURE 4, look-ing in the direction indicated by ythe arrows and rotated from the position of FIGURE 4.

Referring now to the drawings in greater detail, the whipstock of the invention is illustrated in connection with its use in a well -having a bore B in which a casing L is positioned and which may be .provided with a downward extension B of somewhat smaller diameter than the upper portion B `and into which a smaller liner L is extended downwardly from the lower end of the casing L.

The liner L may be connected to the casing L in any conventional manner and suitable packing, such as that indicated at P may be provided to form a iiuid tight seal between the liners whereby fluid may be produced from the Iwell through the casing L and liner L may be of langl 3 suitable size and that the liner L may be cemented in place in the well bore or otherwise supported therein, or that the well bore B may be provided with a casing within which the liners are positioned or which forms a part of the production string of the well.

The liner L may be cut a-nd milled 4away at the `desired location to provide the spaced portions L and L for the positioning of the whipstock in the well.

In positioning :a whipstock in a well equipped in this manner and provided with Ianchoring mechanism of usual construction, adapted to be actuated upon insertion of the whipstock into the upper end of the liner L', the whipstock anchoring mechanism would be actuated to anchor the whipstock in the portion L above the opening provided 'between .the liner portions L and L", Iand it is for the purpose of permitting the whipstock to be passed through the portion L' of the liner and inserted into the upper end of the portion L that the anchoring mechanism of the present invention is provided.

The whipstock of the present invention comprises a lower cylindrically shaped body` portion 10, of a size to be conveniently passed through the liner L', a-nd to whose lower end lthere is attached :the guide portion 12, by which the whipstock is readily inserted into the liner. At its upper end, the body portion is connected to an upper portion 14, by means of a hinged connection having a hinge pin 16, the lower end of the portion 14 and the upper end of the portion 10 being shaped for interengagement and to limit the hinging movement of the parts relative to each other, as best shown in FIGURES 4 and 5, for

v a purpose to be more particularly explained hereinafter.

The upper body portion 14 of the whipstock is elongated and tapers upwardly to form a relatively thin upper end portion 18, which is attached to the lower end of a tubular operating `string 20, as by means of a bolt 22, which may be sheared t-o free the whipstock from the tubing string when the whipstock has been anchored in the liner at the ydesired location. For lthe purpose of Iattaching the tubing string 2t) to the upper end of the whipstock, the lower end of the tubing string may be somewhat flattened, as shown at 24. The upwardly tapering portion of the whipstock is preferably formed with a longitudinally extending concave guiding face 26.

The anchoring mechanism of the invention includes the body portion 10 which is formed with an outwardly opening longitudinal groove, having an upper portion 30 providing -at its lower end an upwardly facing shoulder 32 and a lower portion 34 providing at its lower end an upwardly facing shoulder 36. The bottom walls of the groove portions 30 and 34 slope upwardly `and outwardly longitudinal-ly of the body portion 10. An elongated wedge shaped, externally toothed slip 38 is slidably positioned in the lower portion 34 of the groove, which slip in its lowermost retracted position rests at its lower end on the shoulder 36 and extends upwardly above the shoulder 32. The slip 38 is preferably of T or other suitable shape in lateral cross-section, and the Igroove portion 34 is preferably also similarly shaped in cross-section, so that the head portion of the T of the slip may be slidably intertted with the head portion 35 of the groove 34, as seen in FIGURE 4, to allow the slip to move longitudinally of the body 10 while holding the slip against lateral tilting or swinging movement relative to the body.

The slip 38 has attached thereto at its upper end a pivotally mounted catch 40, as by means `of a pin 42, extending through an inwardly projecting lug 39 on and suitably attached to the slip in any convenient manner as by welding, or the like, which catch extends upwardly above the upper end of the slip in the groove portion 30 for sliding movement therein, land is formed with an outwardly directed hook portion 44 at its upper end. 'Ithe lower end of the catch 4i) extends below the pin 42 and is provided with a downwardly extending leaf spring 46 positioned for engagement with the inner face of the slip 38 to yieldingly ur-ge the upper end of the catch outwardly of the Vof bow or leaf springs 66, whose lower ends are secured v to the body in the grooves, as by means of screws 68, the

groove portion 30. The slip 38 is held in its retracted position by a shear screw 39 carried by -the |body and with which the upper end of the slip is engaged to hold the slip in its downmost position on the body during insertion of the whipstock int-o the well. The lower end portion of the catch 40 is preferably `somewhat tapered to provide a sloping face 48 positioned to engage Ithe bottom of the groove portion 30 to limit outward swinging movement of the catch.

The catch is releasably held in its retracted or inoperative condition by `a wire or pin 50, attached at one end to the upper end of the catch and extending through a di- -ametrical opening 52 in lthe body portion 10, and connected at `its other end to a retainer plate 54, positioned in an outwardly opening counterbore 56 of the opening 52.

The body portion 10 also has a diametrical bore 58 therethrough which is at right angles to -and intersects the diametrical opening 52 and within ywhich shearing element-s 60 and 62 are slidably positioned. The shearing elements 60 and 62 are preferably of cylindrical shape,

and formed at their inner ends for -intertting, sliding engagement, the end portions of the elements having openings therethrough through which the wire or pin 50 may 'y ends of the elements extending outwardly beyond the external surface of the body portion 10.

The body portion 10 is also formed with opposite, outwardly opening longitudinal grooves 64, for the reception upper ends of the springs being free to move in the grooves, and the springs extending mediate their ends over the outer ends of the shearing elements 60 and 62 in position for engagement therewith upon inward flexing of the springs to move the shearing elements inwardly to shear the retaining wire 50.

In the positioning of the whipstock at the desired location in the well, the whipstock is inserted in the casing L, connected t-o the lower end of :the tubing string 20, in the manner illustrated in FIGURE 1, with the slip 38 held in retracted position, as shown in FIGURES 4 and 5 by the shear screw 39, while the catch 40 is held in retracted posit-ion within the groove 30 by the retaining wire 5t), the bow springs 66 being in their :extended positions and the shearing elements 60 and 62 being positioned with their outer ends extendi-ng outwardly beyond the grooves 64 in position to be engaged by the springs 66 upon depression of the springs to move the shearing elements inwardly 4to shear the retaining wire 50. The whipstock in this condition is lowered through the casing L and moved downwardly through the upper portion of the liner L', to position the whipstock with its lower end extending into the lower liner portion L". During downward movement of the whipstock through the liner portion L', the bow springs 66 will be engaged with the liner portion L' to depress the springs into engagement with the outer ends of the shearing elements 6d and 62 to move the shearing elements inwardly to shear the retainer wire 50, whereupon the catch 40 will -be moved to its extended position under the influence of the leaf spring 46, to position the hook portion 44 of the catch for engagement with the upper end of the liner portion L", as shown in FIGURE 3, upon `downward movement of the whipstock in the liner portion L, so that the slip 38 will be held against downward movement with the Iwhipstock to cause the slip to shear the screw 39 to allow the slip to move outwardly into gripping engagement with the liner portion L" upon further downward movement of the whipstock, whereby the whipstock will then be securely anchored in the liner portion L", with the upper tapered portion 14 of the whipstock located in the well bore between the liner portions L and L.

The catch 40 is shaped to prevent the catch from engaging in irregularities at coupling points so that the mechanism will not be accidentally actuated during insertion of the whipstock' in the well.

When the whipstock has thus been anchored at the desired location, a downward force may be exerted by the operating string 20 .to shear the holt 22, whereupon the operating string may be withdrawn from the well :and a suitable drilling bit introduced, attached to the lower end of -an operating string for engagement with the elongated, concave face of the upper portion 14 of the whipstock, whereby the drilling bit will be deected to carry out the drilling operation desired.

It will be apparent that during the insertion of the whipstock in the well, the catch 40 will be held in an inactive position to prevent fthe catch from engaging the upper end of the liner portion L', which would result in premature anchoring of the whipsto-ck in the upper liner portion, but upon downward movement of the whipstock through the upper liner portion L', the bow springs 66 will be depressed to iactuate the shearing elements 60- Iand 62 to release the catch, so that the catch may then move t-o its active position, as seen in FIGURE 2, ready for engagement with the upper end of the lower liner portion L" when the whipstock is lowered therein, to cause the slip 38 to be moved into anchoring position.

It will thus be seen that the invention, constructed and operated as described above, provides whipstock anchoring mechanism which is of simple design and rugged construction, which is positive in operation, and -by the use of which premature anchoring of the whipstock before the whipstock reaches the desired location in the well may be effectively prevented.

The invention is dis-closed herein :in connection with a preferred embodiment of the same, but it will be understood that this is intended by way of example only and that v-arious changes can be made in .the construction and arrangement of the parts within the spirit of the invention and lthe scope of the appended claims.

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

1. In a whipstock for use in a well having upper fand lower vertically spaced well pipe sections therein, a cylindrical body adapted to be lowered into the well pipe, a slip movably mounted on the body for longitudinal movement relative thereto, means on the slip and body positioned for coaction to move the slip to Ya position in wedging engagement with the body and pipe `to Ianchor the body `against longitudinal movement in the pipe upon downward movement 4of the body relative yto the slip, means movably connected to `the slip for movement into and out of :a position for engagement with the upper :end of the lower section of the well pipe to hold the slip against downward movement, yieldable means positioned for coaction with the body and said holding means :to yieldingly urge 'the holding means toward said position, releasable means connected to the body and holding means to hold the holding means out of said position and means mov'ably carried by the body in position for coaction with said releasable means and the upper section :of the pipe to release the holding means upon insertion of the body in said upper section.

2. In a whipstock for use in a well having upper and lower vertically spaced well pipe sections therein, `a cylindrical body adapted to be lowered into the well pipe and having an external, longitudinal groove whose bottom wall slopes longitudinally, a slip slidably disposed in the groove and shaped for coaction with said bottom wall to move the slip outwardly of the body into gripping engagement with the surrounding Wall of the well pipe to anchor the whipstock in the pipe upon longitudinal movement of the body in one direction relative to the slip and to allow the slip .to move out of such gripping engagement upon longitudinal movement of the body in the other direction rela-tive to the slip, means connected to the slip and movable relative .thereto into and out of a position for engagement with the upper end of the lower section of the well pipe to hold the slip against movement in said one direction, releasable means connected to the body #and holding means for holding said holding means out of said posit-ion, means movably carried on lthe body in position for coaction with said releasable means and the upper section of the well pipe upon insertion of the whipstock in said upper section to release said holding means yand yieldable means positioned for coaction with the slip and holding means to yieldingly urge the holding means in said one direction.

3. In a whipstock for use in a well having upper and lower vertically spaced well pipe sections therein, a cylindrical body adapted to be lowered into the well pipe and having an external longitudinal groove whose bottom wall slopes longitudinally, a slip slidably disposed in the groove and shaped for coaction with said bottom wall to move the slip outwardly of the body into gripping engagement with the surrounding wall of the well pipe to anchor the whipstock in the pipe upon longitudinal movement of the body in one direction relative to the slip and to allow the slip to move out of such gripping engagement upon longitudinal movement of the body in the other direction relative to the slip, means connected to the slip and movable relative thereto into and out of a position for engagement with the upper end of the lower section of the well pipe to hold the slip against movement in said one direction, yieldable means positioned for coaction with the body and said holding means to urge the holding means toward said position, releasable means connected to the body and holding means for releasably holding said holding means against movement toward said position and means movably carried on the body in position for coaction with said releasable means and the upper section of said well pipe upon insertion of the whipstock in said upper section -to release said holding means.

4. In a whipstock for use in a well having upper and lower vertically spaced well pipe sections .-therein, a cylindrical body adapted to be lowered into the well pipe and having an external longitudinal groove -whose bottom wall slopes longitudinally, a slip slidably disposed in the groove and having a face disposed for engagement with said bottom .wall to move the slip outwardly of the body into gripping engagement with the surrounding wall of the well pipe upon downward movement of the body relative to the slip, a catch pivotally connected to the slip for swinging movement to an active position extending outwardly from the body for engagement with the upper end of the lower section of the well pipe to hold the slip against downward movement and to an inactive position within said groove, yieldable means positioned for coaction with lthe body and catch to urge the catch toward active position, releasable means connected to the body and catch for releasably holding the catch in said inactive position and means movably carried on the body in position for coaction with the releasable means and the upper section of said well pipe to release said catch upon insertion of the body in said upper section.

5. In a whipstock for use in a well having upper and lower vertically spaced well pipe sections therein, a cylindrical body adapted to be lowered into the well pipe and having an external longitudinal groove whose bottom wall slopes longitudinally, a slip slidably disposed in the groove and having a face disposed for engagement with said bottom wall to move the slip outwardly of the body into gripping engagement with the surrounding wall of the well pipe upon downward movement of the body relative to the slip, a catch pivotally connected to the slip for swinging movement to an active position extending outwardly from the body for engagement with the upper end of the lower section of the well pipe to hold the slip against downward movement and to an inactive position within said groove, yieldable means positioned for coac- References Cited in the file of this patent UNITED STATES PATENTS Kinzbach et a1. Aug. 4, 1931 Kinzbach Jan. 31, 1939 Matlock Apr. 16, 1940 Hester Oct. 9, 1956

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1816856 *Oct 27, 1928Aug 4, 1931Frank KinzbachWhipstock
US2145422 *Jul 25, 1936Jan 31, 1939Kinzbach Robert BWhip stock anchor
US2197344 *Feb 25, 1939Apr 16, 1940Matlock Percy FSetting tool
US2766010 *Mar 6, 1953Oct 9, 1956Gibbs Hester MildredCasing whipstocks
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US3397746 *Dec 30, 1965Aug 20, 1968Directional Service Co Of PeruCirculating mill guide
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Classifications
U.S. Classification166/117.6, 166/216, 175/81
International ClassificationE21B7/04, E21B7/08, E21B7/06
Cooperative ClassificationE21B7/061
European ClassificationE21B7/06B