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Publication numberUS20020070018 A1
Publication typeApplication
Application numberUS 09/732,289
Publication dateJun 13, 2002
Filing dateDec 7, 2000
Priority dateDec 7, 2000
Also published asWO2002046569A1
Publication number09732289, 732289, US 2002/0070018 A1, US 2002/070018 A1, US 20020070018 A1, US 20020070018A1, US 2002070018 A1, US 2002070018A1, US-A1-20020070018, US-A1-2002070018, US2002/0070018A1, US2002/070018A1, US20020070018 A1, US20020070018A1, US2002070018 A1, US2002070018A1
InventorsJean Buyaert
Original AssigneeBuyaert Jean P.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Whipstock orientation system and method
US 20020070018 A1
Abstract
A whipstock assembly and method of operation is disclosed that automatically orients itself within a wellbore to a known first rotational position. The whipstock assembly is mounted on bearings that permit free rotation of the whipstock assembly within the wellbore. Due to gravitational forces, the eccentric weight load of the whipstock will automatically orient itself on the low side of the wellbore. Most wellbores are angled and the angle, azimuth, depth and other information about the wellbore is known so that the operator will know what position the whipstock assembly will automatically assume. A lower orientation section of the whipstock assembly is clamped into that first rotational position such as by a lower packer and/or slips. The whipstock is then rotated to the desired orientation by reciprocating the wellbore string. The whipstock is then clamped into the desired rotational position by activating an upper packer and/or slips. The running tool is removed and drilling or milling can be initiated. After the new wellbore is completed, the whipstock assembly can be retrieved from the wellbore or relocated to a different borehole depth to be used to drill or mill another new borehole section.
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Claims(32)
What is claimed is:
1. A method for orientating a whipstock in a selectable direction, said method comprising:
utilizing a wellbore string for positioning a whipstock assembly containing said whipstock at a depth within a borehole section that is angled in a known direction;
providing that said whipstock assembly is initially free to rotate within said borehole such that a weighted portion of said whipstock assembly is automatically oriented by gravitational forces in a first rotational position.
2. The method of claim 1, further comprising:
affixing an orientation section of said whipstock assembly with respect to said borehole; and
rotating said whipstock with respect to said orientation section to a second rotational position.
3. The method of claim 2, further comprising:
affixing said whipstock with respect to said borehole in said second rotational position.
4. The method of claim 3, wherein said step of affixing said whipstock comprises setting a packer.
5. The method of claim 1, further comprising
engaging a radially moveable member with respect to said borehole to thereby affix an orientation section of said whipstock assembly in said first rotational position.
6. The method of claim 1, further comprising:
providing that said whipstock assembly is rotatable independently from said wellbore string.
7. The method of claim 1, further comprising:
releasing said whipstock assembly from said wellbore string,
initiating drilling of a first new borehole section using said whipstock assembly,
reattaching said wellbore string to whipstock assembly, and
repositioning said whipstock assembly at a second desired depth for drilling a second new borehole section.
8. The method of claim 1, further comprising:
affixing an orientation section of said whipstock assembly by setting a packer.
9. A method for orientating a whipstock in a selectable direction, said method comprising:
positioning a whipstock assembly containing said whipstock at a depth within a borehole;
affixing an orientation section of said whipstock assembly with respect to said borehole in a first rotational position; and
rotating said whipstock with respect to said orientation section to a second rotational position.
10. The method of claim 9, further comprising:
affixing said whipstock with respect to said borehole in said second rotational position responsive to receiving a signal with at least one transducer in said whipstock assembly.
11. The method of claim 9, wherein said step of rotating further comprises:
reciprocally moving a wellbore tubular string a selected number of reciprocal strokes.
12. The method of claim 11, wherein each said reciprocal stroke is translated into a specific amount of rotation of said whipstock.
13. The method of claim 11, wherein each of said steps of affixing comprise setting a packer.
14. A method for orientating a whipstock in a selectable direction, said method comprising:
positioning a whipstock assembly containing said whipstock at a depth within a borehole section with a wellbore string; and
reciprocally moving a wellbore string a selected number of reciprocal strokes such that each said reciprocal stroke is translated into a known amount of rotation of said whipstock.
15. The method of claim 14, further comprising:
providing that said whipstock assembly is initially freely rotatable within said borehole section such that gravitational forces move said whipstock assembly to a first rotational position.
16. The method of claim 15, further comprising:
affixing an orientation section of said whipstock assembly in said first rotational position.
17. The method of claim 16, further comprising:
detecting a signal with said whipstock assembly to initiate said step of affixing.
18. The method of claim 16, further comprising:
utilizing compressed gas for said step of affixing.
19. The system of claim 17, further comprising:
affixing said whipstock with respect to said borehole at a second rotational position.
20. A whipstock assembly for use in a wellbore, comprising:
a whipstock with a guide surface;
an orientation section;
a rotational connection between said whipstock and said orientation section; and
one or more radially moveable members secured to said orientation section, said one or more radially moveable members being radially moveable from a nonengaged position with respect to said wellbore to an engaged position with respect to said wellbore for affixing said orientation section in a first rotational position.
21. The assembly of claim 20, further comprising:
one or more second radially moveable members secured to said whipstock, said said one or more second radially moveable members being radially moveable from a nonengaged position with respect to said wellbore to an engaged position with respect to said wellbore for affixing said whipstock in a second selectable rotational position.
22. The assembly of claim 20, further comprising:
a mechanical motion translator for translating reciprocal movement of said wellbore string into rotational movement of said whipstock with respect to said orientation section.
23. The assembly of claim 20, further comprising:
a transducer attached to said whipstock assembly for receiving a signal.
24. The assembly of claim 20, further comprising
a container for compressed gas.
25. A whipstock assembly for use in a wellbore, said whipstock assembly being moveable to a selectable depth with a wellbore string, said whipstock assembly comprising:
a whipstock with a guide surface;
one or more bearings mounted with respect to said whipstock assembly such that said whipstock assembly is rotatable with respect to said wellbore,
a heavy side of said whipstock assembly, said heavy side being automatically positioned by gravity in a first rotational position.
26. The whipstock assembly of claim 25, further comprising:
one or more radially moveable members secured to said whipstock assembly, said one or more radially moveable members being radially moveable from a nonengaged position with respect to said wellbore to an engaged position with respect to said wellbore.
27. The whipstock assembly of claim 26, further comprising:
one or more transducers for receiving a signal, said one or more radially moveable members being radially moveable in response to said signal.
28. The whipstock assembly of claim 25, further comprising:
an orientation section, and
a selectably rotational connection between said whipstock and said orientation section.
29. The whipstock assembly of claim 25, further comprising:
a compressed gas chamber.
30. A whipstock assembly for use in a wellbore, said whipstock assembly being moveable to a selectable depth with a wellbore string, said whipstock assembly comprising:
a whipstock with a guide surface;
a first set of one or more radially moveable members secured to said whipstock assembly, said one or more radially moveable members being radially moveable from a nonengaged position with respect to said wellbore to an engaged position with respect to said wellbore; and
a second set of one or more second radially moveable members secured to said whipstock assembly, said one or more second radially moveable members being radially moveable from a nonengaged position with respect to said wellbore to an engaged position with respect to said wellbore, said first set of one or more radially member and said second set of one or more second radially moveable members being independently operable for moving from said nonengaged position to said engaged position.
31. The assembly of claim 30, further comprising:
one or more transducers for receiving one or more signals, said first set of one or more radially moveable members and said second set of one or more second radially moveable members each being operable responsively to receiving said one or more signals.
32. The assembly of claim 30, further comprising:
one or more compressed gas chambers.
Description
BACKGROUND OF THE INVENTION

[0001] (1) Field of the Invention

[0002] The present invention relates generally to whipstock orientation and, more particularly, to a whipstock assembly that when positioned downhole automatically orients to a known reference position from which selectable whipstock orientation adjustments can be effected.

[0003] (2) Description of the Prior Art

[0004] It is often desirable, in both cased and open hole, to branch off one or more times from an existing wellbore or to sidetrack away from an object such as a fish or toward an object such as a revised geological target. A whipstock may be used as a guide for the drill bit or mill in creating the new borehole sections, casing windows, and the like, so that the new borehole section is oriented in the desired direction. The whipstock is anchored in the wellbore at the desired depth at which the new well is to be kicked off. The bit or mill engages the generally metallic whipstock face or surface that is typically angled so as to urge the bit or mill in a desired direction. In this manner, it is well known that the mill or drill bit is thereby directed to mill or drill in the direction intended for the new wellbore section.

[0005] However, orienting the whipstock to direct the drill bit or mill, as may typically be desirable for drilling the new wellbore through a particular formation of interest, has been a problem. For the new wellbore to be drilled in the desired direction, the whipstock face must be oriented in the wellbore such that the whipstock face is positioned to guide the bit or mill in that direction. While the whipstock may be lowered on a wellbore string such as a tubular string, the wellbore string will often be quite flexible due to the length thereof so that the direction in which the whipstock is pointing cannot be determined based on the orientation of the wellbore string at the surface. Various methods have been used in the past for orienting the whipstock but these methods generally require running additional tools into the wellbore thus requiring additional valuable rig time for such purposes. For instance, to determine the initial position of the whipstock an orientation survey tool may be run into the well. In cased hole, a non-magnetic orientation survey tool such as a gyroscopic survey tool may be used. In open hole, either a gyroscopic survey tool or a magnetic compass tool may be used. Once the initial position is known, then the pipe is rotated and the orientation survey tool takes another survey to determine if the whipstock is properly oriented. This process is continued until orientation is complete. This is because that due to doglegs, deep depths, crooked hole sections, and the like, it may not be possible to know how much the whipstock has been rotated without use of the subsequent surveys. If the survey tool is a wireline tool, then the survey tool may be rigged up such that it can stay in the pipe during rotation and send the information to the surface. However, this may require a special rig up for the sheave wheels such that the pipe can be manipulated while the wireline remains in the pipe. If the survey tool is operated by slickline, or is a single shot tool such as a battery operated tool, then a separate trip into and out of the hole must be made for each survey because the tool must be retrieved to determine the result. The wireline rig up takes longer and the wireline survey tends to be more expensive than a slickline survey. However, slickline operation requires multiple trips.

[0006] Consequently, it would be desirable to provide a self-orienting whipstock assembly and method that is designed to orient itself in a known rotational orientation within the borehole and, where adjustment from the known rotational orientation is necessary, permits rotation of the whipstock from the known rotational orientation to the desired rotational position without the use of additional tools that require additional trips into the wellbore. Those skilled in the art will appreciate the present invention that addresses the above and other needs and problems.

SUMMARY OF THE INVENTION

[0007] Accordingly, it is an object of the present invention to provide an improved whipstock assembly and method.

[0008] It is yet another object of the present invention to provide a more efficient assembly and method for orienting the whipstock assembly downhole in a desired direction.

[0009] These and other objects, features, and advantages of the present invention will become apparent from the drawings, the descriptions given herein, and the appended claims.

[0010] In accordance with the present invention, a method is provided for orientating a whipstock in a desired direction which may comprise method steps such as the step of utilizing a wellbore string for positioning a whipstock assembly containing the whipstock at a desired depth within a borehole section that is angled in a known direction. An additional step of the method may comprise providing that the whipstock is initially free to rotate within the borehole such that a weighted portion of the whipstock assembly is automatically oriented by gravitational forces in a first rotational position.

[0011] The method may further comprise affixing an orientation section of the whipstock assembly with respect to the borehole in the first rotational position and rotating the whipstock with respect to the orientation section to a second rotational position. Additional steps may comprise affixing the whipstock with respect to the borehole in the second rotational position.

[0012] In one presently preferred embodiment, the step of affixing the whipstock may comprise setting a packer. The method may also comprise affixing an orientation section of the whipstock assembly by setting an inflatable packer. More generally, the method comprises engaging a radially moveable member which may be characterized by an expandable and/or inflatable element and/or may include one or more packers, slips, slips and packers, or any other suitable gripping means with respect to the borehole to thereby affix an orientation section of the whipstock assembly in the first rotational position. In one preferred embodiment, the method includes utilizing compressed gas for the step of affixing such as setting the packer or other affixing means such as slips and the like.

[0013] In one preferred embodiment of the invention, the method includes a step of providing that the whipstock assembly is rotatable independently from the wellbore string. Additional branches from the wellbore can be produced by the steps of releasing the whipstock assembly from the wellbore string, initiating drilling of a first new borehole section using the whipstock assembly, reattaching the wellbore string to whipstock assembly, and repositioning the whipstock assembly at a second desired depth for drilling a second new borehole section.

[0014] In another description, the method may comprise steps such as positioning a whipstock assembly containing the whipstock at a desired depth within a borehole, affixing an orientation section of the whipstock assembly with respect to the borehole in a first rotational position, and rotating the whipstock with respect to the orientation section to a second rotational position. In one preferred embodiment, the step of affixing the whipstock with respect to the borehole in the second rotational position is responsive to receiving a signal, such a signal generated at the surface by mudpumps, with at least one transducer, such as a pressure transducer, in the whipstock assembly. The step of rotating may further comprise reciprocally moving a wellbore tubular string a selected number of reciprocal strokes. Preferably, each reciprocal stroke is translated into a specific amount of rotation of the whipstock. A preferred feature of the present invention includes the step of providing that the whipstock assembly is initially freely rotatable within the borehole section such that gravitational forces move the whipstock assembly to the first rotational position.

[0015] The invention also comprises a whipstock assembly for use in a wellbore that may comprise a whipstock with a guide surface, an orientation section, a rotational connection between the whipstock and the orientation section; and one or more radially moveable members secured to the orientation section. The one or more radially moveable members may be radially moveable from a nonengaged position with respect to the wellbore to an engaged position with respect to the wellbore for affixing the orientation section in the first rotational position.

[0016] As well, one or more second radially moveable members may be secured to the whipstock. Likewise the one or more second radially moveable members secured to the whipstock may be radially moveable from a nonengaged position with respect to the wellbore to an engaged position with respect to the wellbore for affixing the whipstock in the second selectable rotational position.

[0017] A mechanical motion translator may be provided for translating reciprocal movement of the wellbore string into rotational movement between whipstock and the orientation section. A transducer such as a pressure transducer may be attached to the whipstock assembly for receiving a signal and a container may be provided for compressed gas.

[0018] In a preferred embodiment, one or more bearings are preferably mounted with respect to the whipstock assembly such that the whipstock assembly is rotatable with respect to the wellbore. One side of the whipstock assembly comprises a heavy side. Due the bearings, the heavy side may be automatically positioned by gravity in the first rotational position.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] A more complete understanding of the invention and many of the attendant advantages thereto will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein corresponding reference characters indicate corresponding parts throughout the drawing and wherein:

[0020]FIG. 1 is an elevational view, partially in section, of an embodiment of a self orienting whipstock assembly in accord with the present invention;

[0021]FIG. 2 is a cross-sectional view, partially in section, along lines 2-2 of FIG. 1 showing how the whipstock is automatically oriented in an angled borehole;

[0022]FIG. 3 is an elevational view, partially in section, of the self orienting whipstock assembly of FIG. 1 with the lower packer or slips expanded to anchor the assembly in a first rotational position;

[0023]FIG. 4 is an elevational view, partially in section, with a spring of a mechanical translation mechanism compressed to thereby change reciprocal movement of the wellbore string into rotational movement of the whipstock;

[0024]FIG. 5 is an elevational view, partially in section, with the upper packer or slips expanded to anchor the whipstock in the desired rotational position;

[0025]FIG. 6 is an elevational view, partially in section, of the running tool being removed such as by shearing retaining pins;

[0026]FIG. 7 is an elevational view, partially in section, with the whipstock directing a bit or mill in the desired direction to form a new borehole;

[0027]FIG. 8 is an elevational view, partially in section, showing the whipstock assembly adjacent a newly drilled wellbore after the drilling or milling wellbore string has been removed;

[0028]FIG. 9 is an elevational view, partially in section, showing the whipstock assembly being retrieved for removal or for repositioning to drill another borehole; and

[0029]FIG. 10 is an elevational view, showing a slotted sleeve used for mechanical translation of reciprocal movement of the wellbore string into rotational movement of the whipstock.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] Referring now to the drawings and, more particularly, to FIG. 1 there is shown a self orienting whipstock assembly 10 in accord with the present invention. Whipstock assembly 10 is mounted to be free for rotation within wellbore 12. Wellbore 12 may be a cased hole or also an open hole, i.e., casing may have been set at the depth of interest or not. To provide free rotation, whipstock assembly 10 may, for instance, be mounted on bearings such as upper bearing 14, middle bearings 16 and 18, and lower bearing 20. The bearing design variations may include a different number of bearings, different locations, types of bearing, and the like as may be changed as desired to effect free rotation of whipstock assembly 10 within wellbore 12.

[0031] Because whipstock assembly 10 is free to rotate within borehole 12, and because very few boreholes are perfectly vertical, assembly 10 will automatically rotate due to gravitational forces as shown in FIG. 2. In the present design, whipstock 22 provides a shape that has considerable extra weight on one side so that whipstock 22 will cause the whipstock assembly 10 to rotate so that whipstock 22 is at bottom most or low side 24 of borehole 12. Thus, whipstock 22 will move away from high side 26 of borehole 12. Whipstock face 28 is seen to be shaped to form a concave guide surface for guiding the mill or bit. Other face configurations could also be used as desired for guiding the desired type of drilling/milling device.

[0032] While the present invention is ideal for use where it is desirable to conveniently determine the initial rotational position of the whipstock assembly without the need for orientation surveys such as in a deep, deviated wellbores, in some cases knowing the initial position of the whipstock may be unnecessary. Even in a purely vertical borehole 12, it may be desirable to be able to rotate the whipstock from an unknown position by a known amount. To give one example, multiple branches may be made for forming an “umbrella” configuration of boreholes where the initial orientation is not necessary but it is highly desirable to have the multiple boreholes oriented by a known spaced rotational amount. The present invention is also ideal for providing this service without the need for additional orientation surveys by means discussed in detail subsequently. Thus, although the present invention is highly suited to use in deviated wellbores to thereby save time and cost, the present invention is not intended to be limited to use only in deviated wellbores. Moreover, it will be understood that such terms as “up,” “down,” “vertical,” and the like, are made with reference to the drawings and/or the earth and that the devices may not be arranged in such positions at all times depending on variations in operation, transportation, and the like. It will also be understood that the drawings are intended to describe the concepts of the invention so that the presently preferred embodiments of the invention will be plainly disclosed to one of skill in the art but are not intended to be manufacturing level drawings or renditions of final products and may include simplified conceptual views as desired for easier and quicker understanding or explanation of the invention. As well, the relative size of the components may be greatly different from that shown. Moreover, while an angled borehole 12, with respect to the vertical, is shown in FIG. 1 for purposes of explanation, it will be understood that the remainder of views which are shown to be vertically oriented may or may not involve angled boreholes, i.e., deviated boreholes.

[0033] Referring back to FIG. 1, whipstock assembly 10 comprises an upper section referred to herein as whipstock 22 and a lower section referred to as orientation section 30. In this embodiment of the invention, whipstock 22 is connected to orientation section 30 by mandrel 32. Mandrel 32 is interconnected as discussed subsequently, so that at least initially, whipstock 22 and orientation section 30 are locked so as to rotate together.

[0034] Therefore, referring now to FIG. 3, whipstock assembly 10 is positioned at the desired depth and the tool has automatically rotated so that whipstock 22 is in a first rotational position on the bottom side of the wellbore as shown in FIG. 2. The orientation of the wellbore is normally tracked during drilling so that the angle and azimuth of the borehole at any depth are known thereby permitting the operator to determine the orientation that whipstock 22 will automatically assume at the depth where the kickoff of the new borehole is to be. Thus after positioning whipstock assembly 10 at this depth, lower clamping member 34 is activated as shown so as to expand radially outwardly to grip or engage borehole 12. Lower clamping member 34 may be a packer, slips, or a combination of slips and packer. Clamping member 34 may be one or more elements that expand or move radially outwardly to grippingly engage borehole 12 and affix orientation section 30 in a known first rotational position. In a presently preferred embodiment, clamping member 34 is an inflatable packer.

[0035] It may happen that in the first rotational position, whipstock 22 is already at the desired rotational position which will guide the bit or mill in the desired direction intended for the new borehole. However, normally this may not be the case. It will therefore typically be necessary to rotate whipstock 22 with respect to orientation section 30 by an amount which the operator will know because he already knows the desired direction of the new borehole and he knows the first rotational position at which whipstock 22 will be automatically oriented in wellbore 12 prior to and just after activating clamping member 34.

[0036]FIG. 4 illustrates how whipstock 22 is rotated with respect to orientation section 30. In a presently preferred embodiment, this action is accomplished by using a mechanical motion translator to translate reciprocal movement of wellbore string 55 (see FIG. 1 and FIG. 3) as indicated by arrow 36 in a downward direction. This action compresses spring 39 as indicated in FIG. 4. Referring back to FIG. 3, it is seen that spring 39 is uncompressed. This reciprocal compressing—uncompressing action moves mandrel 32 downwardly as indicated in FIG. 4 from the position of mandrel 32 as shown in FIG. 3. Attached to mandrel 32 is key 38. Key 38 moves through slotted sleeve 40. A projection of slotted cylindrical sleeve 40 is shown in FIG. 10 as a plane surface 42 with grooves 44 and cam surfaces 46. Key 38 then moves as indicated by arrows and numbers in FIG. 10. Reciprocal movement of wellstring 55 as indicated by arrow 36 causes key 38 to follow grooves 44 and cam surfaces 46 thereby cause key 38 and, therefore, mandrel 32 to rotate. Mandrel 32 is attached to whipstock 22 so that whipstock 22 therefore rotates with respect to orientation section 30. Depending on the spacing of the grooves, the amount and direction of rotation for each reciprocal stroke is known. For instance, if it desired to rotate ninety degrees in the direction of rotation, and each reciprocal stroke produces thirty degrees of rotation of whipstock 22, then the operator strokes the whipstock assembly three times. Generally, if the whipstock is within about thirty degrees of the desired orientation for the new wellbore section, then that is sufficiently accurate for most applications. However, greater accuracy could be obtained with grooves having smaller spacings therebetween. As well, a specific slotted sleeve 40 could be tailor made for a specific application if even more accuracy was desired.

[0037] It will be seen that mandrel 32 also rotationally locks whipstock 22 and orientation section 30 together due to the position of mandrel key 38 in grooves 44 which are biased to remain in position within grooves 44 by spring 39. After lower clamping member 34 is activated, spring 39 can be compressed due to the affixed position of orientation section 30 to thereby select the desired orientation of whipstock 22. Thus, with orientation section 30 affixed wellbore 12, relative reciprocal or longitudinal movement between whipstock 22 and orientation section 30 is possible by reciprocal movement of wellbore string 55 to thereby also rotate whipstock 22 with respect to orientation section 30.

[0038] In FIG. 5, whipstock 22 has been oriented to the desired position such as by one or more reciprocal strokes as discussed above. At this time, upper clamping member 48 is activated to thereby lock whipstock 22 into a second desired rotational orientation. Upper clamping member 48 may be a packer, slips, or a combination of slips and packer. Upper clamping member 48 may be one or more elements that expand or move radially outwardly to grippingly engage wellbore 12 and affix orientation section whipstock 22 in the second rotational position, which is the desired position. Due to engagement of upper clamping member 48, pressure applied to whipstock 22 will no longer move whipstock 22 downwardly so that further rotation of whipstock 22 is prevented. In a presently preferred embodiment, upper clamping member 48 is an inflatable packer.

[0039] In FIG. 6, running tool 50 is removed by pulling upwardly on the wellbore string 55 to shear pins, bolts or disks 52. Other connections and means for releasing the whipstock may be used such as connections which are used to release other types of downhole tools in the wellbore. Thus, shear pins, disks, or bolts are provided as an example only of one method of releasing the wellbore string and whipstock assembly 12. Running tool 50 may preferably include bearings or rotatable connection 53 so as to permit whipstock assembly 10 to rotate freely with respect to wellbore string 55. Shear pins, bolts, or disks 52 could also be connect to a rotational connection to effect this purpose. In any case, whipstock assembly 10 is preferably freely rotatable with respect to wellbore string 55 and may be released therefrom when desired.

[0040] In FIG. 7, a new wellbore string 54 is run into wellbore 12 with bit or mill 56 to open a window in the casing or initiate drilling as the situation may call for. Whipstock 22 guides bit or mill 56 in the desired direction for the new borehole or casing window.

[0041] In FIG. 8, new lateral borehole 58 has been drilled and wellbore string 54 is removed. Upper connector 60, which may be of numerous types, is available for connection to remove or relocate whipstock assembly 10 once upper and lower clamping members 48 and 34, respectively, have been released. In FIG. 9, pulling tool 62 engages upper connector 60 for retrieving whipstock assembly 10. As will be noted upper and lower clamping member 48 and 34 have been released prior to retrieval. If pulling tool 62 is used for relocating whipstock assembly 10 elsewhere to produce another new wellbore, then pulling tool 62 will be designed to release from whipstock assembly 10 as discussed above and may use shear pins, bolts, or other means such as tension responsive bolts and sleeves, actuators that respond to a pressure switch as do the valves discussed hereinafter, or other suitable means for connecting to and/or releasing whipstock assembly 10.

[0042] Various means may be used for engaging and releasing upper and lower clamping members 48 and 34. In one embodiment, a liquid nitrogen reservoir 64 may be used with associated valves 66 and 68 for applying pressure from liquid nitrogen reservoir 64 to the respective upper and lower clamping members 48 and 34. One or more pressure transducers and controls, such as transducers 70 and 72 may be used for controlling the valves. For instance each transducer 70 may include a logic circuit that responds to a particular signal to open or close the respective valve in response to a particular code of pressure pulses that may be produced, for example only, by cycling the surface mud pumps. High temperature lithium batteries may be encapsulated for powering the logic circuit, such as a microprocessor and for controlling the valves. For example, once the pressure signal for activating the lower clamping member is received and recognized by transducers such as 70 and 72, which transducer packages may also include a microprocessor and batteries, then valve 66 may be opened for a given period of time so that enough nitrogen is taken from reservoir 64 into lower clamping member 34 which may be an inflatable/expandable packer. A different signal could be used for upper clamping member 48. Various methods could be provided for deflation as well. For instance, a different signal could be used and valves 66 and 68 could be three way valves to bleed off pressure into wellbore 12 and/or annulus 74. Mechanical means such as internal sliding sleeves could be used to shear pins. The sliding sleeves would shear the pins when a selected tension is applied to the whipstock assembly 10 by means of pulling tool 62, to allow the nitrogen to bleed off through sleeve ports into wellbore 12 and/or annulus 74. The above discussion related to activating upper and lower clamping members 34 and 48 is given as an example only because numerous different methods are available for activating clamping members such as packers, plugs, and slips including mechanical, explosive, electrical means.

[0043] In summary, whipstock assembly 10 is run into wellbore 12 to the desired depth at which the new wellbore is to be kicked off from wellbore 12. Whipstock 10 automatically orients itself to the low side 24 of wellbore 12 as shown in FIG. 2 which position is known beforehand to the operator as discussed above. Lower clamping member 34 affixes orientation section 30 with respect to wellbore 12 in the first rotational position. The wellbore string including running tool 50 is reciprocated to thereby rotate whipstock 22 to the desired second rotational postion. Upper clamping member 48 is then activated to affix whipstock 22 in position. Running tool 50 is removed and the milling or drilling assembly is then used to kickoff new wellbore 58. Once completed, whipstock assembly 10 can be retrieved by releasing upper and lower clamping members 48 and 34 after reconnecting with whipstock assembly 10 using retrieving tool 62. Retrieving tool 62 may be used to remove whipstock assembly 10 from wellbore 12 or relocate whipstock assembly 10 elsewhere in borehole 12 or new wellbore 58 to kick off another wellbore.

[0044] While the discussion above relates to using a wellbore string for running whipstock assembly 10 into wellbore 12 such as a pipe, drilling, or tubing string, other types of wellbore strings such as sucker rods, wireline, or slickline could also be used. Different adaptations could then be made as appropriate. For instance with wireline, electrical power is generally available and could be used, for instance to activate the clamping members, rotate the whipstock such as with an electric motor, and the like. Alternatively wireline or slickline jars or weight sections could be used to produce a reciprocal movement for rotating whipstock 22 as discussed above. As stated above, other types of connectors for running tool and pulling tool 62 could be used.

[0045] Thus, numerous variations of the above method are possible, some of which have already been described. Therefore, it will be understood that many additional changes in the details, materials, steps and arrangement of parts, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US6786282 *Jun 24, 2002Sep 7, 2004Schlumberger Technology CorporationMilling apparatus and method for a well
US6935422 *Jan 27, 2004Aug 30, 2005Halliburton Energy Services, Inc.Expanding wellbore junction
US6968903 *Sep 23, 2003Nov 29, 2005Tiw CorporationOrientable whipstock tool and method
US7353867 *Apr 14, 2003Apr 8, 2008Weatherford/Lamb. Inc.Whipstock assembly and method of manufacture
US7467672May 5, 2006Dec 23, 2008Smith International, Inc.Orientation tool
US7669672 *Oct 23, 2006Mar 2, 2010Charles BrunetApparatus, system and method for installing boreholes from a main wellbore
US7971645Apr 3, 2009Jul 5, 2011Baker Hughes IncorporatedFour mill bottom hole assembly
US7997336 *Aug 1, 2008Aug 16, 2011Weatherford/Lamb, Inc.Method and apparatus for retrieving an assembly from a wellbore
US8245774 *Apr 8, 2008Aug 21, 2012Weatherford/Lamb, Inc.Whipstock assembly for forming a window within a wellbore casing
US8286708May 20, 2009Oct 16, 2012Schlumberger Technology CorporationMethods and apparatuses for installing lateral wells
US8763685Nov 8, 2011Jul 1, 2014Baker Hughes IncorporatedWhipstock assembly and method for low side exit
US8813856Apr 15, 2011Aug 26, 2014Charles BrunetDownhole tubing shift tool and method
WO2006071832A1 *Dec 22, 2005Jul 6, 2006Cdx Gas LlcAdjustable window liner
WO2010135376A1 *May 18, 2010Nov 25, 2010Schlumberger Canada LimitedMethods and apparatuses for installing lateral wells
WO2013015967A2 *Jul 6, 2012Jan 31, 2013Baker Hughes IncorporatedWhipstock assembly and method for low side exit
Classifications
U.S. Classification166/255.3, 175/61, 166/117.6, 175/80, 166/50
International ClassificationE21B7/06, E21B23/00, E21B7/08, E21B23/01
Cooperative ClassificationE21B23/006, E21B7/061, E21B23/01
European ClassificationE21B23/01, E21B7/06B, E21B23/00M2
Legal Events
DateCodeEventDescription
Apr 12, 2001ASAssignment
Owner name: FRANK S INTERNATIONAL, TEXAS
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:BUYTAERT, JEAN P.;REEL/FRAME:011660/0966
Effective date: 20001127