Trip Sub Assembly with Check Valve

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.

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

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.

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

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.

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.

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/packerhas been utilized to deploy a production liner within the slotted liner. The liner top packer anchorhas been installed together with a thermal anchor, and a dual purpose packer lock assembly, profile sub including a trip sub assembly. 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 assemblycomprises a top suband a bottom housing, 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 housingfits within and seals off the bottom housing. The ported piston housinghas an upper shoulder which bears on an internal shoulder within the bottom housing which prevents downward movement of the ported piston housingwithin the bottom housing. The piston housingdefines at least one lateral port, and in one preferred embodiment, has 4 lateral ports which are aligned and spaced equidistantly around the perimeter of the piston housing. The lateral portsprovide fluid communication through the piston housing from below the deviceto the internal bore.

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

A pistonis slidingly disposed within the ported piston housing, and comprises a ball seat, elastomeric retaining ringand lateral portsA, and comprises a piston stemB. In a run-in-hole (RIH) position, the portsA are aligned with the piston housing portsA, as is shown in. Shear screwsretains the pistonin the RIH position within the ported piston housing, until activation is initiated. The pistonhas an internal bore open through the top of the piston and which opens to the lateral portsA.

The trip sub assemblymay 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 portsA and the piston housing portsA are aligned.

Activation of the trip submay be accomplished by seating a ballin the ball seatof the piston, which ball has a diameter greater than the ball seat, and slightly greater than the elastomeric retaining ringinner diameter. The ball is pushed past the retaining ringby the pump down pressure and is then maintained in position by the retaining ring. 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. Once the shear screws are sheared, the pistonthen shifts downwards to close off the lateral portsA, as is shown in. No fluid may flow through the piston, and the deviceis 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 openingis defined in an upper surface of the piston housing, and is preferably closed by an optional burst discwhich has a design pressure at which it yields to open the flow path of the bypass B. The check valve collarincludes at least one check valve, positioned within the bypass flow path to block fluid from flowing upwards while allowing fluid to pass downwards through the trip sub. As the width of the check valve collar limits the size of the check valve, it is preferable to include two or more check valves, configured in series as shown, or in parallel through the check valve collar.

Preferably, the piston housingand pistoncomprise a ratchet mechanismformed by ratchet teethformed on the inner surface of piston housingand corresponding ratchet teethon the surface of the piston stemB. The ratchet mechanismallows downward movement of the pistonwithin the piston housing, but prevents upward movement once engaged, as may be seen in. Thus, once the device is blanked off, the piston will remain in the closed position.

Preferably, the trip sub assemblycomprises an equalizing sleevewhich is slidingly disposed within the top sub, to facilitate retrieval. The equalizing sleeve is sealed to the inner diameter of the top sub, and covers portsA, but may be shifted into an open position, where the portsA are open. A lock body (not shown) pushes down onto the equalizing sleeveduring the retrieval process and shifts the equalizing sleeveinto the open position, where it does not cover portsA, as may be seen in. 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 submay a sealed volume when the trip subhas 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 valvein the trip subpermits pressure relief by allowing pressure to escape downwards into the production liner below the trip sub, once the pressure exceeds the burst disc pressure rating.

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.