Multilateral reference point
A multilateral reference point sleeve includes a tubular member configured to be received in a tubing string of a wellbore. The tubular member has an uphole end and a downhole end. The uphole end is angled to define an orientation profile, and the orientation profile has an orientation slot extending therefrom. A method for orienting a tool in a wellbore includes running the multilateral reference point sleeve into the casing in the wellbore, anchoring the sleeve to an inner surface of the casing, running the tool into the tubing string, causing a pin on the tool to engage the orientation profile on the sleeve, and causing the pin on the tool to engage the orientation slot on the orientation profile.
This application claims the benefit of an earlier filing date from U.S. Ser. No. 09/898,795, filed Jul. 3, 2001, which itself claims an earlier filing date from U.S. Ser. No. 60/216,807, filed Jul. 7, 2000, respectively, the entire contents of both of which are incorporated herein by reference.
BACKGROUNDIn existing oil and gas wells where a multilateral junction is employed to effect lateral drilling into oil and gas formations not accessed by the primary wellbore, re-entry can be a difficult proposition. Several tools currently exist for locating a window for re-entry but each has disadvantages in either operation or cost.
SUMMARYA multilateral reference point sleeve and a method for orienting a tool in a wellbore to facilitate the installation of a multilateral junction or re-entry to a lateral borehole are disclosed. An advantage to the disclosed device and method is that the sleeve of the device has a relatively thin wall thickness, which allows for a minimum amount of reduction in cross sectional area of the wellbore in the vicinity of the installed device. The device comprises a sleeve configured to be received in a casing of a wellbore. The sleeve has an uphole end and a downhole end. The uphole end includes an edge that defines an orientation profile.
At the downhole most section of the orientation profile, an orientation slot extends therefrom in a downhole direction. The orientation slot is configured to receive a pin on a tool run in the hole to engage the device causing the tool to orient to a particular direction as calculated by the placement of the pin at the surface.
The sleeve is anchorable within the casing through the radial expansion of the downhole end of the sleeve against an inner surface of the casing. In one embodiment, the wall thickness of the sleeve proximate the downhole end of thereof is reduced as compared to the thickness of the wall proximate the uphole end of the sleeve resulting in easier expansion of the sleeve by methods such as swaging and inflatables which do not require specific discussion.
The method for orienting a tool in the wellbore includes running the multilateral reference point sleeve in the hole, anchoring the sleeve to the inner surface of the casing, and running a tool into the sleeve. Once the tool engages the sleeve, a pin on the tool engages the orientation profile and causes the rotation of the tool. Rotation stops when the pin drops into the slot. When properly oriented, the pin drops into the orientation slot, thereby causing the tool to maintain its proper orientation, which allows for control over direction for lateral drilling.
BRIEF DESCRIPTION OF THE DRAWINGS
The multilateral reference point sleeve is a tubular member that is positionable within the casing of a wellbore to define a reference point for the installation of a multilateral junction or to facilitate re-entry to a lateral borehole at a later operation. The sleeve has an orientation profile along an uphole edge and an orientation slot cut or formed therein to lock a tool into its proper orientation, thereby ensuring proper rotational alignment of the tool with respect to the wellbore.
Referring to
Tubular member 12 is of a cross sectional shape that substantially conforms to the cross sectional shape of the casing of a wellbore (shown below with reference to
Referring now to
Uphole end 14 of tubular member 12 is configured to form an angle 28 relative to the surface of wall 24. Therefore, the overall length of sleeve 10 from uphole end 14 to downhole end 16 is variable and has a value dependent upon the point on wall 24 at which the length is measured. Angle 28 defines orientation profile 20 of sleeve 10 having thickness LU. Angle 28 may be of any common orientation profile angle known to the art. Referring to
Referring back to
It should be appreciated that the reference point disclosed may be installed before or after the creation of a multilateral junction. Where such is installed before the junction, it may be used to assist in locating tools to create the junction. In the event it is installed after the completion of the junction it is useful in assisting re-entry operations.
Referring now to
Referring to
As a pin located on the tool engages orientation profile 20, the pin follows along orientation profile 20 until it reaches the most downhole point of orientation profile 20 where it moves into orientation slot 18. As the pin follows orientation profile 20, the tool to which the pin is connected rotates and is oriented within sleeve 10 and is properly situated for the desired operation. The exact rotational position of sleeve 10 can be determined using standard tools and methods either before installing sleeve 10 at the proper depth in casing 36 or thereafter.
If desired in some applications, a collet groove (not shown) may be added to tubular member 12 for use in securing tools to the sleeve. A collet mechanism on the tool can be used to secure the tool in the sleeve 10.
From this position, sleeve 10 can also provide a depth register. Sleeve 10 is intended to be positioned below the point at which the installation of the multilateral junction is desired or has been created. By the engagement of the tool with orientation profile 20, an operator at the surface can direct the drilling of a lateral wellbore into a gas and oil formation or re-entry thereto with great precision.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.
Claims
1. An orientation device comprising:
- a single piece unitary sleeve, at least partially circumferentially closed, having at least a portion thereof configured to be expandable such that the single piece unitary sleeve exhibits a first circumference prior to being expanded and a second circumference subsequent to the sleeve being expanded; and
- an orientation profile disposed at the sleeve configured to orient tools passing at least partially through the device.
2. The orientation device as claimed in claim 1 wherein the portion configured to be expandable is sufficiently expandable in outside dimension to create a supportive interference fit with a tubular structure in which said device is installable.
3. The orientation device as claimed in claim 1 wherein the orientation profile includes an apex.
4. The orientation device as claimed in claim 1 wherein the orientation profile causes automatic orientation of another tool passing at least partially through the device, the automatic orientation occurring in one of two rotational directions.
5. The orientation device as claimed in claim 4 wherein the two rotational directions are determined based upon on which side of an apex of the orientation profile the other tool contacts the orientation profile.
6. The orientation device as claimed in claim 1 wherein a downhole end of the sleeve has a lesser thickness than an uphole end of the sleeve.
7. The orientation device as claimed in claim 1 wherein the orientation profile further includes an orientation opening extending therefrom.
8. The orientation device as claimed in claim 7 wherein the slot is positioned about 180° from an apex of the profile.
9. The orientation device as claimed in claim 7 wherein the orientation opening extends along a wall of the sleeve and is configured to receive a pin on a separate tool and to maintain the oriented position of the separate tool.
10. The orientation device as claimed in claim 9 wherein the pin on the separate tool engages the orientation profile and rotates the tool into a desired orientation.
Type: Application
Filed: Apr 28, 2006
Publication Date: Aug 31, 2006
Inventor: Douglas Murray (Humble, TX)
Application Number: 11/413,467
International Classification: E21B 43/00 (20060101); E21B 43/04 (20060101);