In a variety of multilateral well systems, diverters are used to facilitate reentry into either the main or lateral wellbores. During construction of the junction between the main wellbore and a lateral wellbore, a diverter may be installed as a torque tube for running the junction equipment. Subsequently, the diverter is pulled and a drilling diverter is installed to facilitate a drilling operation. Drilling diverters generally are designed to snap into engagement with downhole equipment, e.g. completion equipment, positioned in the well. Upon completion of the drilling operation, the drilling diverter is disengaged by applying a tensile snap out force. To avoid unwanted disengagement, however, drilling diverters are designed such that a substantial snap out force is used to disengage the drilling diverter.
In general, the present disclosure provides a system and method for employing a diverter latch assembly in cooperation with a lateral wellbore. The diverter latch assembly comprises an upper latch assembly coupled with a lower latch assembly via a swivel. The upper latch assembly also comprises a releasable latch positioned to engage a tieback receptacle located in the well. The swivel and the releasable latch are designed to enable rotation of the releasable latch relative to a tubing of the lower latch assembly during release of the diverter latch assembly from the tieback receptacle. The rotational release system facilitates controlled release and withdrawal of the diverter latch assembly with a reduced risk of damage to the diverter latch assembly or other downhole components.
However, many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.
Certain embodiments of the disclosure will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements. It should be understood, however, that the accompanying figures illustrate the various implementations described herein and are not meant to limit the scope of various technologies described herein, and:
In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
The present disclosure generally involves a system and methodology that relate to facilitating operations in a lateral wellbore. The system and methodology utilize a diverter latch assembly which may be sealed across a lateral junction and comprises an upper latch assembly coupled with a lower latch assembly via a swivel. The upper latch assembly also comprises a releasable latch positioned to engage a tieback receptacle located in the well. The swivel and the releasable latch are designed to enable rotation of the releasable latch relative to tubing (e.g. relative to a latch assembly casing) of the lower latch assembly during release of the diverter latch assembly from the tieback receptacle. The rotational release system facilitates controlled release and withdrawal of the diverter latch assembly while reducing risk of damage to the diverter latch assembly or other downhole components. In many applications, the diverter latch assembly may be used to facilitate a drilling operation while providing a sealed connection across a junction with a lateral wellbore. However, the diverter latch assembly also may be used to facilitate a variety of other types of operations, e.g injection operations or well preparation operations.
By way of example, during the construction of a TAML level 3-5 multilateral junction, the length of a lateral wellbore may be increased by drilling further into the formation. This drilling operation can be accomplished by running a drilling string through a lateral wellbore section and drilling into an open hole to increase the length of the lateral leg of the well. The present system and methodology provides an assembly which enables formation of a junction between the main wellbore and the lateral wellbore which has hydraulic integrity while also facilitating easy removal of the assembly upon completion of the drilling operation and/or other operation.
In preparing for the drilling operation, various types of equipment may be deployed downhole. For example, completion equipment may be deployed downhole and may comprise a plurality of tieback receptacles designed to receive a diverter system which enables the drill string to be diverted into the desired lateral wellbore. As described herein, the diverter system comprises a drilling diverter latch assembly that may be deployed with a standard running tool, e.g. a standard liner hanger running tool with a standard profile. The drilling diverter latch assembly also may be constructed to provide a large inner diameter to facilitate running of drill bits with large outer diameters. The drilling diverter latch assembly also may comprise anti pre-release features which prevent the drilling diverter latch assembly from being released accidentally while tripping the drill string through the diverter system. Additionally, the drilling diverter latch assembly may comprise a rotational release/latch system having a rotational release bearing which allows controlled release of the assembly from a tieback receptacle via rotation of an upper portion of the assembly. The assembly also may comprise built-in seals and debris barriers to isolate the junction while protecting the assembly from debris which could otherwise interfere with the releasable latch system.
Referring generally to
In the example of
In the example illustrated, the downhole well equipment 32 may comprise a lateral bore assembly 34 having a lower tieback receptacle 36 deployed in the lateral wellbore 26. Additionally, well equipment 32 may comprise various components located in main wellbore 24, including a main bore assembly 38 used in cooperation with a polished bore receptacle 40. In the example illustrated, a main bore liner 42 is located below the polished bore receptacle 40 and above both a production latch assembly 44 and a lower main wellbore tieback receptacle 46. Other components, such as a packer 48 and a liner hanger 50 also may be positioned below junction 28. Above junction 28, the well equipment 32 may comprise a variety of components, such as a lateral packer 52, a lateral packer alignment sub 54, and an upper tieback receptacle 56.
Similarly, the diverter latch assembly 30 also may comprise a variety of components and arrangements of components. In the specific example illustrated, diverter latch assembly 30 is constructed as a drilling diverter latch assembly and comprises a lower latch assembly portion 58 of the overall drilling diverter latch assembly 30 coupled with an upper latch assembly portion 60 of the overall drilling diverter latch assembly 30. In this example, the upper portion 60 is selectively engaged with and latched into the upper tieback receptacle 56. In at least some applications, the lower portion 58 may comprise a relatively long section of tubing 62, e.g. diverter casing, that bends into lateral wellbore 26 through junction 28 below upper portion 60.
In
Referring generally to
The top sub 74 may be coupled with an alignment mule 78, e.g. a mule sleeve, via an engagement feature 80, such as a plurality of castellations 82 (see
In the example illustrated, the torque sub 84 is coupled to a body 94, e.g. a tubular body/seal mandrel, by a releasable member 96, such as a collet 98. The releasable member 96 and the engagement feature 80 cooperate to form a diverter latch 100, e.g. a drilling diverter latch, which can be used to selectively release the diverter latch assembly 30 from the upper tieback receptacle 56 for removal of the diverter latch assembly 30. In the example illustrated, collet 98 is a threaded collet having a plurality of flexible fingers 102 with threaded regions 104 (see
Flexible fingers 102 allow the diverter latch assembly 30 to be linearly moved, e.g. stabbed, into engagement with threaded region 106 of upper tieback receptacle 56. However, release of collet 98 from the upper tieback receptacle 56 involves rotation of torque sub 84 and collet 98 to unthread threaded regions 104 from corresponding threaded region 106. Thus, release of diverter latch assembly 30 involves axial movement of top sub 74 to release top sub 74 from alignment mule 78 via disengagement of castellations 82 followed by rotation of top sub 74, torque sub 84, and collet 98 to release collet 98 from the upper tieback receptacle 56. In some applications, the threaded regions 104 are designed so that the collet 98 is rotated several times prior to release, e.g. 10-30 rotations or in some applications 20-25 rotations. A cone feature 108 may be positioned on body 94 proximate collet fingers 102 such that an axial, tensile force applied to diverter latch assembly 30 prior to release of collet 98 effectively forces the flexible fingers 102 in a radially outward direction and into more secure engagement with the surrounding threaded region 106 of upper tieback receptacle 56.
The upper portion 60 of diverter latch assembly 30 may be coupled to the lower portion 58 of diverter latch assembly 30 across a swivel 110. Rotation of collet 98 is facilitated by swivel 110, which effectively allows the upper portion 60 to rotate relative to the lower portion 58 of diverter latch assembly 30. In the example illustrated, swivel 110 comprises a swivel housing 112 connected between body 94 and a crossover tubing 114. The crossover tubing 114, in turn, is connected to tubing 62 of the lower portion 58 of diverter latch assembly 30. The swivel housing 112 may be connected to body 94 by a suitable fastener 116, such as at least one setscrew. Accordingly, swivel 110 allows the joined top sub 74, torque sub 84, and body 94 to rotate relative to crossover tubing 112 and the lower portion 58 of diverter latch assembly 30.
By way of example, swivel 110 may comprise a ball bearing style swivel. With added reference to
The upper portion 60 of diverter latch assembly 30 also may comprise a variety of other or additional features. For example, a bearing 132 may be positioned between the torque sub 84 and the surrounding alignment mule 78, as further illustrated in
Additionally, a plurality of the seals 68 may be positioned along body 94 to provide sealing engagement with the interior surface of upper tieback receptacle 56. Although a variety of seals 68 may be employed, an example is illustrated in
In some applications, a shear member 152, such as a shear screw, also may be positioned between top sub 74 and alignment mule 78 to avoid inadvertent disengagement of engagement feature 80. For example, the shear member 152 can be used to block separation of castellations 82 until an axial pulling force above a predetermined threshold is applied to the top sub 74. Additionally, top sub 74 or another suitable component, may comprise a running tool engagement feature 154, such as the internal annular recess illustrated in
Referring generally to
In an operational example, drilling diverter latch assembly 30 is run in hole led by stinger 64 and a relatively long section of tubing 62, e.g. drilling diverter casing, that may extend 60-90 feet (18-28 m) in length. Jointed pipe and a liner hanger style running tool may be used to convey the drilling diverter latch assembly into the well 22. Once the latch 100 of the drilling diverter latch assembly 30 reaches the upper, lateral packer tieback receptacle 56, the latch 100 engages the mating threaded profile 106 to lock the drilling diverter latch assembly 30 in place.
The mated mule shoe shaped surfaces of alignment mule 78 and corresponding alignment mule 156 properly align the assembly 30 and prevent unwanted rotation of the drilling diverter latch assembly 30. The cone feature 108 on the body 94 ensures that any upward force created by the drilling pressure transfers into the diverter latch 100, e.g. collet 98, and prevents premature release. Additionally, the seals 68 on the body 94 provide a hydraulic seal within the tieback receptacle 56. In this example, lower hydraulic isolation is provided by seals 66 on stinger 64 which seal against a lower tieback receptacle 36 which may be in the form of a lateral liner.
At this stage, a drilling operation may be performed and drilling of the lateral lining can occur once the running tool string is removed and the drill string is run in hole. The drilling diverter latch assembly 30 is not removable without an upward stroke of the top sub 74 and a subsequent rotation of collet 98 to disengage the threaded regions 104 from the corresponding threads 106 of the tieback receptacle 56. Downward forces on the drilling diverter latch assembly are transferred into the latch 100 and subsequently into the upper tieback receptacle 100. However, once removal of the drilling diverter latch assembly 30 is desired, the running tool string is again run to depth and latched into the top sub 74 via running tool engagement feature 154. Tension is then applied the top sub 74 in an axial, uphole direction to create a space between the top sub 74 and the alignment mule 78. This axial shifting disengages the castellated splines 82 and allows the latch 100, and specifically collet 98, to be rotated via the running tool without rotating the alignment mule 78.
The bearing feature 132 located within the alignment mule 78 facilitates free rotation of the top sub 74, torque sub 84, and body 94 without rotating the alignment mule 78. The system may be designed to accommodate rotation in either direction. In an example, however, the threaded regions 104 engaged with corresponding threads 106 of tieback receptacle 56 have a left-hand thread feature such that a right-hand rotation begins to disengage the drilling diverter latch assembly 30 from the upper tieback receptacle 56. After a predetermined number of turns, e.g. 20-25 turns, the drilling diverter latch assembly 30 is freed without rotating the lower portion 58 of the drilling diverter latch assembly 30. Once free, the drilling diverter latch assembly 30 can be pulled out of hole.
Shear members 124 may be used in swivel 110 so the torque applied to release drilling diverter latch assembly 30 is greater than a predetermined amount of resistance provided by the shear members 124. Once the shear members 124 are sheared, the collet 98 may be freely rotated (without rotating the relatively long section of drilling diverter casing 62) until the drilling diverter latch assembly 30 is released. The shear members 124, e.g. shear pins, protect against inadvertent release of the latch 100 due to various smaller level torques that may be applied during running in hole and/or during engagement of the drilling diverter latch assembly 30 with the downhole equipment 32. It should be noted the various debris barrier features described above are designed to prevent the accumulation of large amounts of debris proximate the diverter latch 100 which could inhibit retrieval of the drilling diverter latch assembly 30.
Depending on the parameters of a given application, the diverter latch assembly 30 may be used to facilitate movement of various tubing strings from main wellbore 24 into lateral wellbore 26. In drilling applications, the design of the diverter latch assembly 30 facilitates movement of drill strings and drill bits having relatively large diameters into the lateral wellbore. During the drilling or other operation in lateral wellbore 26, the lower seals 66 and the upper seals 68, 150 provide hydraulic isolation with respect to junction 28. However, various types of seals and sealing systems may be employed along the diverter latch assembly 30 to provide a desired hydraulic isolation.
Additionally, the diverter latch assembly 30 may be designed in various configurations with selected lengths suitable to span junction 28. The diverter latch assembly 30 also may comprise various other and/or additional components designed to facilitate aspects of a given operation in the lateral wellbore. Similarly, the diverter latch 100 may comprise many types of components designed to facilitate selective engagement as well as disengagement via the sequential longitudinal and rotational movements that control disengagement and separation of the diverter latch assembly from the downhole equipment.
By way of further example, the overall system may utilize many types of downhole well equipment 32. The downhole well equipment 32 may comprise a variety of completion components in both the main wellbore and the lateral wellbore to facilitate desired production operations or other types of operations. The equipment also may comprise various components and arrangements of components to address parameters of a given environment and/or well structure.
Although a few embodiments of the disclosure have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.