LATERAL JUNCTION ASSEMBLY
The present invention relates to a lateral junction assembly (1) for providing a lateral junction in a wellbore by being inserted into a casing (60) having an opening (61) and defining a longitudinal axis (52), the lateral junction assembly (1) having a longitudinal direction (50) which is substantially parallel to the longitudinal axis (52) and comprising a pipe module (10) comprising a pipe section (12) for being inserted through the opening (61) in the casing and a flange (11), wherein the lateral junction assembly further comprises a fixation element (25) adapted for being connected with the flange (11) to fixate the pipe module (10) in a predetermined location with the pipe section extending through the opening (61) in the casing (60).
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The present invention relates to a lateral junction assembly for providing a lateral junction in a wellbore by being inserted into a casing having an opening and defining a longitudinal axis. Furthermore, the invention relates to a lateral junction system for providing a lateral junction in a wellbore. Moreover, the invention relates to a wireline tool for transporting, positioning and assembling a lateral junction assembly in a casing. Finally, the present invention relates to a method of installing a lateral junction assembly in a wellbore.
BACKGROUND ARTA lateral wellbore is a branch of a primary wellbore and is often referred to as a lateral or side track. If a well has a plurality of laterals, it is referred to as a multi-lateral.
Designing wells with laterals is a way of increasing the yield of an oil or gas field and may contribute to reducing the costs associated with drilling operations. Laterals may be created before the well is completed or at a later stage after the well has been cased. When making a lateral after the well has been cased, the junction between the primary casing and the lateral has to be installed at the location downhole. It is very difficult to perform a welding operation downhole, and the sealing between the lateral junction and the casing often fails.
U.S. Pat. No. 5,388,648 discloses different solutions wherein deformable devices are utilised for sealing the junction between vertical and lateral wells. Different types of deformable devices are lowered into a well prior to or after the well has been cased. Subsequently, the devices are deformed to obtain the intended shape of the lateral junction and cemented in place. A disadvantage in this respect is the use of cement or other curable liquid in the design of a lateral junction between a primary well and a lateral well. Furthermore, to deform the device subsequently induces the risk of leaks.
Laterals are created downhole, and the precision of such operation may therefore be difficult to control, constituting a limiting feature. At the same time, it is important that the lateral junction is properly sealed to avoid outflow from the casing back into the formation.
SUMMARY OF THE INVENTIONIt is an object of the present invention to wholly or partly overcome the above disadvantages and drawbacks of the prior art. More specifically, it is an object to provide an improved assembly which is easy to implement in an existing casing and still provides the necessary sealing effect.
The above objects, together with numerous other objects, advantages, and features, which will become evident from the below description, are accomplished by a solution in accordance with the present invention by a lateral junction assembly for providing a lateral junction in a wellbore by being inserted into a casing having an opening (61) and defining a longitudinal axis, the lateral junction assembly having a longitudinal direction which is substantially parallel to the longitudinal axis and comprising:
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- a pipe module comprising a pipe section for being inserted through the opening in the casing and a flange,
wherein the lateral junction assembly further comprises a fixation element adapted for being connected with the flange to fixate the pipe module in a predetermined location with the pipe section extending through the opening in the casing.
- a pipe module comprising a pipe section for being inserted through the opening in the casing and a flange,
An advantage in this respect is that a lateral junction can be provided by simply assembling standard modules downhole. By connecting the fixation element to the flange, the pipe module is pushed against the inner surface of the casing and thereby secured in the predetermined position. The lateral junction provided does not require precision welding, cementing or other types of casting or custom operations to ensure a liquid-tight lateral junction.
In one embodiment, the pipe section may extend from a first surface of the flange, and the fixation element, when connected to the flange, may extend from a second surface of the flange opposite the first surface of the flange.
The lateral junction assembly may further comprise a sealing element arranged at the first surface of the flange.
Moreover, the assembly may comprise two or more fixation elements.
The side edges of the fixation elements and the side edges of the flange may be provided with indentations or grooves or serrations to improve the bonding properties between the side edges of the fixation elements and between the side edges of the flange and the side edges of the fixation elements.
Further, the one or more fixation elements may be sections of a hollow cylinder.
Moreover, the one or more fixation elements may be sections of a circular ring.
Also, a cross-section of the flange may constitute a first part of a circular ring and the one or more fixation elements may constitute a second and remaining part of the circular ring.
In another embodiment, the lateral junction assembly may comprise one or more fixation elements distributed in the longitudinal direction of the lateral junction assembly.
The lateral junction assembly may comprise one or more fixation elements positioned adjacent to a first edge of the flange and one or more fixation elements positioned adjacent to a second edge of the flange.
Further, the lateral junction assembly may comprise one or more fixation elements positioned substantially in a middle part of the flange in the longitudinal direction.
Additionally, the lateral junction assembly may comprise two or more pipe modules.
Also, the pipe module may comprise two or more pipe sections extending from the flange.
An advantage in this respect is that the distance between two laterals may be controlled by the distance between the pipe sections extending from the flange. Thus, the distance between two laterals does not have to be measured out.
The present invention furthermore relates to a lateral junction system for providing a lateral junction in a wellbore, the lateral junction system comprising:
-
- a primary casing having an inner surface and at least one opening, the primary casing defining a longitudinal axis, and
- a lateral junction assembly as described above,
wherein the pipe module is positioned such that the pipe section extends through the opening of the casing and the one or more fixation elements pushes the first surface of the flange towards the inner surface of the casing, whereby the pipe module is secured in a predetermined location.
Hereby, a modular system is provided having modules that can be transported to a desired location downhole and assembled to create a lateral junction. The modular system can be retrofitted to old wells or used in the completion of new wells. The modular system does not require precision welding to provide a liquid-tight lateral junction. The modules can be welded together to increase the strength of the system, but the welding does not affect the quality of the seals.
Furthermore, the lateral junction may comprise a lateral casing adapted to be connected to the pipe section of the pipe module.
In addition, the pipe module may have an extension in a transverse plane perpendicular to the longitudinal axis, the extension being smaller than an inner diameter of the casing.
Moreover, each of the fixation elements may have an extension in a transverse plane which is perpendicular to the longitudinal axis, the extension being smaller than an inner diameter of the casing.
Also, a cross-section of the flange may constitute a first part of a circular ring, and the one or more fixation elements may constitute a second and remaining part of the circular ring, an outer periphery of the ring being substantially equal to or slightly larger than an inner periphery of the casing.
The present invention further relates a wireline tool for transporting, positioning and assembling a lateral junction assembly as described above, the wireline tool comprising:
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- an electronic unit for powering to the wireline tool,
- a motor unit,
- a pump unit,
- a driving unit moving the wireline tool downhole,
- a logging unit for determining the position in a casing downhole,
- a transportation unit for transporting and positioning the pipe module and the one or more fixation elements, and
- an assembly unit for assembling the lateral junction assembly downhole.
Moreover, the present invention relates to a method of installing a lateral junction assembly in a wellbore having a casing with at least one opening, the method comprising the steps of:
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- lowering a pipe module comprising a pipe section and a flange into a wellbore,
- lowering one or more fixation elements adapted for being connected with the flange into a wellbore,
- positioning the pipe module in the casing with the pipe section extending through the opening of the casing,
- joining the flange of the pipe module with the one or more fixation elements, thereby fixating the lateral junction assembly in a predetermined location.
In said method, the side edges of the flange of the pipe module and side edges of the one or more fixation elements may be joined by cold welding caused by the side edges being pressed against each other.
In the lateral junction assembly as described above, the fixation element may be a flexible member for pushing the pipe section through an opening in the flange.
Also, the flexible member may be a sheet of spring steel.
In an embodiment, the flexible member may be formed as strands and made of spring steel.
Moreover, the fixation element may comprise multiple spring members for pushing the pipe section through an opening in the flange.
The lateral junction assembly as described above may further comprise one or more locking devices extending from the pipe section and being adapted to fixate the pipe section in an activated position wherein the pipe section extends through the opening in the flange.
Said one or more locking devices may be springs, such as leaf springs, extending from the pipe section towards the flexible member.
Further, the lateral junction assembly as described above may further comprise one or more activation members adapted to prevent the pipe section from being pushed through the opening in the casing by the fixation element.
The present invention also relates to a lateral junction system for providing a lateral junction in a wellbore, comprising:
-
- a primary casing having an inner surface and at least one opening, the primary casing defining a longitudinal axis, and
- a lateral junction assembly as described above,
wherein the pipe module is positioned such that the pipe section extends through the opening in the flange and the opening of the casing, whereby the lateral junction assembly is secured in a predetermined location.
In addition, the present invention relates to a wireline tool for transporting, positioning and activating a lateral junction assembly as described above in a casing, the wireline tool comprising:
-
- an electronic unit for powering to the wireline tool,
- a motor unit,
- a pump unit,
- a driving unit moving the wireline tool downhole,
- a logging unit for determining the position in a casing downhole,
- a transportation unit for transporting and positioning the lateral junction assembly, and
- an activation unit for activating the lateral junction assembly downhole by removing one or more activation members of the lateral junction assembly.
Also, the wireline tool as described above may further comprise an expander cone for pushing the pipe section of the lateral junction assembly through the opening in the flange and the opening in the casing.
Finally, the present invention relates to a method of installing a lateral junction assembly in a wellbore having a casing with at least one opening, the method comprising the steps of:
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- lowering a lateral junction assembly as described above into a wellbore,
- positioning the lateral junction assembly in the casing with the pipe section aligned with the opening of the casing,
- activating the lateral junction assembly downhole by removing one or more activation members, so that the pipe section extends through the opening in the casing, and
- fixating the lateral junction assembly in a predetermined location by means of the one or more locking devices.
This method may further comprise the step of pulling or pushing an expander cone past the lateral junction assembly downhole, whereby the pipe section is pushed through the opening in the flange and the opening in the casing.
The invention and its many advantages will be described in more detail below with reference to the accompanying schematic drawings, which for the purpose of illustration show some non-limiting embodiments and in which
All the figures are highly schematic and not necessarily to scale, and they show only those parts which are necessary in order to elucidate the invention, other parts being omitted or merely suggested.
DETAILED DESCRIPTION OF THE INVENTIONThe pipe module 10 comprises a flange 11 extending in the longitudinal direction 50 from a bottom edge 15a to a top edge 16a. The flange is curved in a direction transverse to the longitudinal direction 50. A pipe section 12 extends from an outer surface 13 of the flange 11 and a sealing material 14 is positioned on the outer surface 13 extending around the pipe section 12. The sealing material 14 has the shape of a strip but may be shaped and positioned in various manners that will be evident for a person skilled in the art. The pipe module further comprises a passage 18 extending from an inner surface 19 of the flange, through the flange 11 and through the pipe section 12.
Referring to
The lateral junction assembly 1 may comprise more than one fixation element 25 to fixate the pipe module 10. One fixation element 25 may be positioned adjacent to the top end 16a of the lateral junction assembly 1, and another fixation element 25 may be positioned adjacent to the bottom end 15a.
The pipe section 10 and the fixation element 25 are assembled by positioning the end pieces 26 of fixation element 25 in the recesses 20 in the flange 11. Hereby, the fixation element 25, in combination with the flange 11, creates a cylindrical ring having an outer periphery when seen in a cross-sectional view of
In use the lateral junction assembly 1 according to
The fixation element 25 has a diameter equal to or slightly larger than the inner diameter of the casing 60. To be able to lower the fixation element 25 down into the casing 60, the fixation element 25 has to be slightly compressed compared to its original size. When the pipe module 10 has been positioned with the pipe section 12 extending through the opening 61 in the casing 60 and the end pieces 26 of a fixation element have been inserted in the recesses 20, the fixation element 25 is returned to its original size. Hereby, a radial pressure is provided on the flange 11 towards the casing 60.
The pipe module 10 comprises a flange 11 extending in the longitudinal direction 50 from a bottom edge 15a to a top edge 16a and being curved in a direction transverse to the longitudinal direction 50. A pipe section 12 extends from an outer surface 13 of the flange 11. On an outer surface 13 of the flange a sealing material 14 is positioned around the extending pipe section 12. The sealing material 14 has the shape of a strip but may be shaped and positioned in various manners that will be evident for a person skilled in the art. The pipe module further comprises a passage 18 extending in a direction parallel to a lateral axis 51 from an inner surface 19 of the flange, through the flange 11 and through the pipe section 12.
The first fixation part 21 and the second fixation part 22 each has two side edges 23, a top edge 16b and a bottom edge 15b. The fixation parts 21, 22 are curved having a radius of curvature which is substantially equal to the radius of curvature of the flange 11.
In use the lateral junction assembly 1 according to
To secure the lateral junction assembly 1 in the casing and create the necessary pressure on the flange, a certain amount of tension is needed in the lateral junction assembly 1. Hereby a sealing effect is provided between the flange and the inner surface 62 of the casing.
The lateral junction assembly 1 is assembled by positioning the fixation parts 21, 22 and the pipe module 10 substantially as shown in
Now referring to
On the side edges 17, 23 small indentations or grooves forming peaks (not shown) may be provided for improving the mutual bonding properties between the fixation parts 21, 22 and the bonding properties between the fixation parts 21, 22 and the flange 11. When the fixation parts 21, 22 and the flange 11 are assembled inside the casing 60 as shown in
Referring to
The side edges 23 of the fixation parts 24a, 24b, 24c, 24d are provided with indentations or grooves forming peaks (not shown) for improving the bonding properties as described earlier.
In
The flange 11 may be configured in a number of different ways such as, but not limited to, as a circle, an oval, a rectangle, a square, a trapezium, etc. The fixation elements may also de shaped differently from what is shown in the drawing. The flange 11 of the pipe module 10 and the fixation elements 21, 22 may be shaped like wedges or trapeziums and together constitute a hollow cylinder. The fixation elements and flange 11 may then be joined by sliding the fixation elements in a longitudinal direction 50 relative to the flange from a position either above or below. As the top edge 16b of the fixation elements reaches the top edge 16a of the flange 11, side edges 17, 23 come into abutment against each other. When the top edges 16a, 16b are aligned, a hollow cylinder is created, and the pipe module 10 has been wedged into the casing.
Referring to
Next, a pipe module 10 and a set of the fixation elements 21, 22, 24a, 24b, 24c, 24d, 25 are lowered into a cased wellbore, e.g. transported by a downhole tractor or well tool suspended from a wireline as described later. Arriving at a predetermined location inside the casing wherein an opening 61 has been provided, the pipe module 10 is positioned with the pipe section 12 extending through the opening 61 as shown in
When the lateral junction assembly 1 has been installed, the inner diameter of the primary casing comprising the lateral junction is smaller than the inner diameter of other sections of the casing.
On an outer surface of the pipe section 112, one or more locking devices 115 are provided for fixating the pipe section 112 when it has been pushed through the opening 117 as shown in
In use the lateral junction assembly 100 is lowered into a cased wellbore and positioned in the same way as the embodiments shown in
By fluid or well fluid is meant any kind of fluid that may be present in oil or gas wells downhole, such as natural gas, oil, oil mud, crude oil, water, etc. By gas is meant any kind of gas composition present in a well, completion, or open hole, and by oil is meant any kind of oil composition, such as crude oil, an oil-containing fluid, etc. Gas, oil, and water fluids may thus all comprise other elements or substances than gas, oil, and/or water, respectively.
By a casing is meant any kind of pipe, tubing, tubular, liner, string etc. used downhole in relation to oil or natural gas production.
In the event that the tools are not submergible all the way into the casing, a downhole tractor can be used to push the tools all the way into position in the well. A downhole tractor is any kind of driving tool capable of pushing or pulling tools in a well downhole, such as a Well Tractor®.
Although the invention has been described in the above in connection with preferred embodiments of the invention, it will be evident for a person skilled in the art that several modifications are conceivable without departing from the invention as defined by the following claims.
Claims
1-26. (canceled)
27. A lateral junction assembly (1) for providing a lateral junction in a wellbore by being inserted into a casing having an opening (61) and defining a longitudinal axis (52), the lateral junction assembly having a longitudinal direction (50) which is substantially parallel to the longitudinal axis and comprising:
- a pipe module (10) comprising a pipe section (12) for being inserted through the opening in the casing and a flange (11, 111),
- wherein the lateral junction assembly further comprises a fixation element (25, 125) adapted for being connected with the flange to fixate the pipe module in a predetermined location with the pipe section extending through the opening in the casing.
28. A lateral junction assembly according to claim 27, wherein the pipe section extends from a first surface (13) of the flange, and the fixation element, when connected to the flange, extends from a second surface (19) of the flange opposite the first surface of the flange.
29. A lateral junction assembly according to claim 27, further comprising a sealing element (14) arranged at the first surface of the flange.
30. A lateral junction assembly according to claim 27, wherein the assembly comprises two or more fixation elements (21, 22, 24a, 24b, 24c, 24d, 25).
31. A lateral junction assembly according to claim 30, wherein the one or more fixation elements are sections of a hollow cylinder.
32. A lateral junction assembly according to claim 27, wherein a cross-section of the flange constitutes a first part of a circular ring and the one or more fixation elements constitute a second and remaining part of the circular ring.
33. A lateral junction assembly according to claim 27, comprising one or more fixation elements distributed in the longitudinal direction of the lateral junction assembly.
34. Lateral junction assembly according to claim 27, wherein the fixation element is a flexible member for pushing the pipe section through an opening (117) in the flange.
35. A lateral junction assembly according to claim 34, wherein the flexible member is a sheet of spring steel.
36. A lateral junction assembly according to claim 27, wherein the fixation element comprises multiple spring members for pushing the pipe section through an opening (117) in the flange.
37. A lateral junction assembly according to claim 27, further comprising one or more locking devices (115) extending from the pipe section and being adapted to fixate the pipe section in an activated position wherein the pipe section extends through the opening in the flange.
38. A lateral junction system for providing a lateral junction in a wellbore, the lateral junction system comprising:
- a primary casing (60) having an inner surface (62) and at least one opening (61), the primary casing defining a longitudinal axis (52), and
- a lateral junction assembly (1) according to claim 27,
- wherein the pipe module is positioned such that the pipe section extends through the opening of the casing and the one or more fixation elements pushes the first surface of the flange towards the inner surface of the casing, whereby the pipe module is secured in a predetermined location.
39. A lateral junction system according to claim 38, wherein the pipe module has an extension in a transverse plane perpendicular to the longitudinal axis, the extension being smaller than an inner diameter of the casing.
40. A lateral junction system according to claim 38, wherein a cross-section of the flange constitutes a first part of a circular ring, and the one or more fixation elements constitute a second and remaining part of the circular ring, an outer periphery of the ring being substantially equal to or slightly larger than an inner periphery of the casing.
41. A wireline tool for transporting, positioning and assembling a lateral junction assembly according to claim 27 in a casing, the wireline tool comprising:
- an electronic unit for powering to the wireline tool,
- a motor unit,
- a pump unit,
- a driving unit moving the wireline tool downhole,
- a logging unit for determining the position in a casing downhole,
- a transportation unit for transporting and positioning the pipe module and the one or more fixation elements, and
- an assembly unit for assembling the lateral junction assembly downhole.
42. A method of installing a lateral junction assembly in a wellbore having a casing with at least one opening, the method comprising the steps of:
- lowering a pipe module comprising a pipe section and a flange into a wellbore,
- lowering one or more fixation elements adapted for being connected with the flange into a wellbore,
- positioning the pipe module in the casing with the pipe section extending through the opening of the casing,
- joining the flange of the pipe module with the one or more fixation elements, thereby fixating the lateral junction assembly in a predetermined location.
43. A method according to claim 42, wherein side edges of the flange of the pipe module and side edges of the one or more fixation elements are joined by cold welding caused by the side edges being pressed against each other.
44. A wireline tool for transporting, positioning and activating a lateral junction assembly according to claim 34 in a casing, the wireline tool comprising:
- an electronic unit for powering to the wireline tool,
- a motor unit,
- a pump unit,
- a driving unit moving the wireline tool downhole,
- a logging unit for determining the position in a casing downhole,
- a transportation unit for transporting and positioning the lateral junction assembly, and
- an activation unit for activating the lateral junction assembly downhole by removing one or more activation members (116) of the lateral junction assembly.
45. A wireline tool according to claim 44, further comprising an expander cone (88) for pushing the pipe section of the lateral junction assembly through the opening in the flange and the opening in the casing.
46. A method of installing a lateral junction assembly in a wellbore having a casing with at least one opening, the method comprising the steps of:
- lowering a lateral junction assembly according to claim 34 into a wellbore,
- positioning the lateral junction assembly in the casing with the pipe section aligned with the opening of the casing,
- activating the lateral junction assembly downhole by removing one or more activation members, so that the pipe section extends through the opening in the casing, and
- fixating the lateral junction assembly in a predetermined location by means of the one or more locking devices.
Type: Application
Filed: Dec 21, 2011
Publication Date: Oct 31, 2013
Applicant: WELLTEC A/S (Allerod)
Inventor: Jørgen Hallundbæk (Graested)
Application Number: 13/996,871
International Classification: E21B 41/00 (20060101);