TRIP SUB ASSEMBLY WITH CHECK VALVE

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of U.S. Provisional Patent Application No. 63/661,722, entitled TRIP SUB ASSEMBLY WITH DUAL CHECK VALVES, filed on Jun. 19, 2024, the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention generally relates to an improved trip sub assembly for use with a packer and bridge plug.

BACKGROUND

Retrievable bridge plugs are used in thermal well operations to isolate the reservoir or wellbore. Circulating plugs can hold pressure from below and allow flow from above, and may be used to plug formation pressure in the tubing string while providing flow area for pumping into the formation. Plugs with equalizing standing valves allow flow through the plug from below while holding pressure from above.

A dual purpose packer and bridge plug allows circulation through the liner during deployment and setting of a liner top packer anchor. The dual purpose packer and bridge plug may be redeployed and set as a bridge plug or a liner hanger packer inside a slotted liner. A trip sub is installed in the tool string and run in hole in an open position allowing fluid to be circulated down the work string and into the liner.

SUMMARY OF THE INVENTION

In one aspect, disclosed is a trip sub device comprising:

• • a top sub and a bottom housing together defining an internal bore;
  • a piston housing positioned within and sealed to the bottom housing, defining an internal passage and defining a primary flowpath port and a bypass flowpath, both flowpaths permitting fluid communication from the internal bore through the piston housing;
  • a piston slidingly disposed and sealed within the piston housing, the piston defining a flowpath through the piston and at least one lateral port, wherein in a running position the lateral port is aligned with the primary flowpath port, and in an activated position the lateral port is closed by an internal surface of the piston housing, wherein the piston is moveable in response to pressure within the piston housing to slide downwards within the piston housing; and
  • at least one check valve within the bypass flowpath, to prevent upward flow of fluid in the bypass flowpath, while permitting downward flow.

In a preferred embodiment, the device further comprises a burst disc sealing an entrance to the bypass flowpath.

In use, once a completion string comprising the liner top packer/hanger and liner are at a correct depth, a ball is dropped from surface and displaced to the trip sub seat. Once the ball lands in the seat, fluid pressure shifts the sub into the closed position. This allows for the circulation path to be blanked off and to pressure up, which allows for completion equipment to be hydraulically set.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate some, but not the only or exclusive, examples of embodiments and/or features.

FIG. 1 shows a schematic depiction of one embodiment of a trip sub device as described herein, in one example of use, installed downhole from a dual purpose packer and bridge plug in position in a wellbore.

FIG. 2 shows a cut-away cross-sectional view of one embodiment of the device, in a running-in-hole (RIH) configuration. FIG. 2A includes detailed view of inset A.

FIG. 3A shows an axial cross-sectional view of the embodiment of FIG. 2, in RIH configuration. FIG. 3B shows the same device activated with a ball, shifted to a closed configuration.

FIG. 4 shows the same view as FIG. 3A, with the device in a retrieval configuration.

DETAILED DESCRIPTION

The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are exemplified. Indeed, this invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. It is to be understood that this invention is not limited to the particular methodology and protocols described, as such may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which the invention pertains having the benefit of the teachings presented in the foregoing description and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

In this description, the directional prepositions of up, upwardly, down, downwardly, front, back, top, upper, bottom, lower, left, right and other such terms refer to the device as it is oriented and appears in the drawings and are used for convenience only; they are not intended to be limiting or to imply that the device has to be used or positioned in any particular orientation. The drawings are shown with the device displayed horizontally, with the uphole end on the left. Conventional components of the invention are elements that are well-known in the prior art and will not be discussed in detail for this disclosure.

FIG. 1 shows a schematic depiction of a wellbore which has been conventionally completed with a production casing PC which extends through the build section, and a slotted liner positioned in the horizontal section. A liner top packer anchor/packer 100 has been utilized to deploy a production liner within the slotted liner. The liner top packer anchor 100 has been installed together with a thermal anchor 110, and a dual purpose packer lock assembly, profile sub including a trip sub assembly 10. This portion of the downhole assembly is described in detail in U.S. patent application Ser. No. 18/610,500, filed Mar. 20, 2024, entitled Thermal Liner Top Anchor Packer, the entire contents of which are incorporated herein by reference, where permitted.

The trip sub assembly 10 comprises a top sub 1 and a bottom housing 2, which are attached together to form a cylindrical housing and which define an internal bore. O-ring seals are provided to prevent fluid ingress or egress. A cylindrical ported piston housing 3 fits within and seals off the bottom housing 2. The ported piston housing 3 has an upper shoulder which bears on an internal shoulder within the bottom housing which prevents downward movement of the ported piston housing 3 within the bottom housing 2. The piston housing 3 defines at least one lateral port 3a, and in one preferred embodiment, has 4 lateral ports which are aligned and spaced equidistantly around the perimeter of the piston housing 3. The lateral ports 3a provide fluid communication through the piston housing from below the device 10 to the internal bore.

A bypass channel B is defined within an upper portion of the ported piston housing 3, which channel provides bypass fluid communication between the internal bore and the annular space between the piston housing 3 and the bottom housing 2, which is open to fluids below the device 10. This annular space between the ported piston housing 3 and the bottom housing 2 is sealed closed with an annular check valve collar 19, which houses at least one check valve 18 in fluid communication with the bypass channel B, as described below. Preferably, there are two check valves, installed in series in the check valve collar 19.

A piston 4 is slidingly disposed within the ported piston housing 3, and comprises a ball seat 5, elastomeric retaining ring 6 and lateral ports 4A, and comprises a piston stem 4B. In a run-in-hole (RIH) position, the ports 4A are aligned with the piston housing ports 3A, as is shown in FIG. 2. Shear screws 7 retains the piston 4 in the RIH position within the ported piston housing 3, until activation is initiated. The piston 4 has an internal bore open through the top of the piston and which opens to the lateral ports 4A.

The trip sub assembly 10 may be pumped down as part of the work string described above until landed and installed in a profile sub. Flow through is provided because the piston ports 4A and the piston housing ports 3A are aligned.

Activation of the trip sub 10 may be accomplished by seating a ball 8 in the ball seat 5 of the piston, which ball has a diameter greater than the ball seat 5, and slightly greater than the elastomeric retaining ring 6 inner diameter. The ball is pushed past the retaining ring 6 by the pump down pressure and is then maintained in position by the retaining ring 6. Seating the ball allows fluid pressure in the production casing PC to build above the device, until sufficient pressure builds to exceed the shear strength of shear screws 7. Once the shear screws are sheared, the piston 4 then shifts downwards to close off the lateral ports 4A, as is shown in FIG. 3. No fluid may flow through the piston, and the device 10 is now blanked off. The operator may then pressure up to set uphole equipment such as an anchor and/or a liner top packer.

The bypass opening 40 is defined in an upper surface of the piston housing 3, and is preferably closed by an optional burst disc 9 which has a design pressure at which it yields to open the flow path of the bypass B. The check valve collar 19 includes at least one check valve 18, positioned within the bypass flow path to block fluid from flowing upwards while allowing fluid to pass downwards through the trip sub 10. As the width of the check valve collar limits the size of the check valve 18, it is preferable to include two or more check valves 18, configured in series as shown, or in parallel through the check valve collar 19.

Preferably, the piston housing 3 and piston 4 comprise a ratchet mechanism 30 formed by ratchet teeth 30a formed on the inner surface of piston housing 3 and corresponding ratchet teeth 30b on the surface of the piston stem 4B. The ratchet mechanism 30 allows downward movement of the piston 4 within the piston housing 3, but prevents upward movement once engaged, as may be seen in FIG. 3. Thus, once the device is blanked off, the piston will remain in the closed position.

Preferably, the trip sub assembly 10 comprises an equalizing sleeve 50 which is slidingly disposed within the top sub 1, to facilitate retrieval. The equalizing sleeve is sealed to the inner diameter of the top sub 1, and covers ports 1A, but may be shifted into an open position, where the ports 1A are open. A lock body (not shown) pushes down onto the equalizing sleeve 50 during the retrieval process and shifts the equalizing sleeve 50 into the open position, where it does not cover ports 1A, as may be seen in FIG. 4. When opened, fluid/pressure is allowed to communicate above and below the device, facilitating its retrieval.

In one exemplary use case, the trip sub may be installed below a thermal liner top packer and a thermal anchor, in a thermal producing well. A standard wireline retrieval plug WRP, or a plug having a check valve such as that described in co-pending U.S. patent application Ser. No. 19/036,310, the entire contents of which are incorporated herein by reference, may be installed in an uphole position. The volume between the WRP and the trip sub 10 may a sealed volume when the trip sub 10 has been blanked off. If the fluids in this volume undergo significant thermal expansion, structural damage could occur. In such a scenario, the at least one check valve 18 in the trip sub 10 permits pressure relief by allowing pressure to escape downwards into the production liner below the trip sub 18, once the pressure exceeds the burst disc pressure rating.

Interpretation.

The forgoing description supplies specific details in order to provide a thorough understanding. Nevertheless, the skilled artisan would understand that the apparatuses, systems, and associated methods of using the apparatuses and systems can be implemented and used without employing these specific details. Indeed, the apparatuses, systems, and associated methods can be placed into practice by modifying the illustrated apparatus and associated methods and can be used in conjunction with any other apparatus and techniques conventionally used in the industry.

The corresponding structures, materials, acts, and equivalents of all means or steps plus function elements in the claims appended to this specification are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed.

References in the specification to “one embodiment”, “an embodiment”, etc., indicate that the embodiment described may include a particular aspect, feature, structure, or characteristic, but not every embodiment necessarily includes that aspect, feature, structure, or characteristic. Moreover, such phrases may, but do not necessarily, refer to the same embodiment referred to in other portions of the specification. Further, when a particular aspect, feature, structure, or characteristic is described in connection with an embodiment, it is within the knowledge of one skilled in the art to affect or connect such module, aspect, feature, structure, or characteristic with other embodiments, whether or not explicitly described. In other words, any module, element or feature may be combined with any other element or feature in different embodiments, unless there is an obvious or inherent incompatibility, or it is specifically excluded.

It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for the use of exclusive terminology, such as “solely,” “only,” and the like, in connection with the recitation of claim elements or use of a “negative” limitation. The terms “preferably,” “preferred,” “prefer,” “optionally,” “may,” and similar terms are used to indicate that an item, condition or step being referred to is an optional (not required) feature of the invention.

The singular forms “a,” “an,” and “the” include the plural reference unless the context clearly dictates otherwise. The term “and/or” means any one of the items, any combination of the items, or all of the items with which this term is associated. The phrase “one or more” is readily understood by one of skill in the art, particularly when read in context of its usage.

As will also be understood by one skilled in the art, all language such as “up to”, “at least”, “greater than”, “less than”, “more than”, “or more”, and the like, include the number recited and such terms refer to ranges that can be subsequently broken down into sub-ranges as discussed above. In the same manner, all ratios recited herein also include all sub-ratios falling within the broader ratio.