Float Valve Systems

Abstract

A system and method for controlling fluid flow inside a tubular in a wellbore includes a tubular comprising an internal bore and a latch profile on an inner surface of the tubular. A receiver is positioned within the internal bore of the tubular at the latch profile so that the tubular and the receiver form a unit for insertion into the wellbore. An interior of the receiver defines a fluid flow channel, and the fluid flow channel includes an internal taper. A float valve is provided for dropping into the wellbore and the receiver. The float valve includes an external taper at an external surface of the float valve, and the external taper abuts against the internal taper of the receiver so that the float valve in the receiver blocks the fluid flow channel.

Description

FIELD

The present disclosure generally relates to a system and method for controlling fluid flow inside a tubular in a wellbore. More particularly, the disclosure relates to a float valve which can be lowered into a wellbore subsequent to a casing or other tubular, latching within said tubular, and providing a selectively actuated fluid barrier.

BACKGROUND

Conventionally, the oil and gas industry has utilized one-way float valves for a variety of applications, including oil and gas wellbore operations. One such application is the use of float shoes and float collars, which are designed to prevent backflow of cement slurry into the annulus of a casing or other tubular string, and thereby enable the casing to “float” in the wellbore. Typically, these float shoes and float collars are attached to the end of a casing string and lowered into the wellbore during casing operations.

Such a process, however, renders the float equipment vulnerable to a variety of problems, such as obstruction or deformation due to debris which is introduced to the float valve during circulation of mud or other drilling fluids. Additionally, unforeseen complications in downhole conditions may render other float equipment with, e.g., higher-strength materials or different designs, more suited to cementing operations after the fact.

There is thus a need for systems and methods in which a float valve can be dropped or lowered into the wellbore subsequent to the running of casing strings or drill strings.

Embodiments of the float valve system and method of use, disclosed herein, achieve these needs.

SUMMARY

The present disclosure is directed to a system and method of using float valves, including float collars and float shoes, suitable for use in subterranean drilling. In an embodiment, the system comprises a float valve receiver which is inserted into a tubular, such as float housing. The float housing may comprise a casing coupling joint. The float valve receiver may comprise a drillable material defining a receptacle within the inner diameter, the receptacle comprising tapered sides to receive a suitable float valve. The float valve receiver can be fixed in place in the tubular or float housing with a sealing ring and locking ring located around grooves on the outer diameter of the float valve receiver.

The float valve receiver can be positioned within the float housing with the receptacle empty, and lowered within the wellbore along with the casing. Subsequent to the casing being positioned within the wellbore, a float valve can be dropped down the wellbore, where it falls towards the receptacle. The outer diameter of the float valve can be sized and contoured to match the inner diameter receptacle of the float housing, and the float valve can also comprise a sealing ring and locking ring positioned around grooves in the outer diameter of the float valve. Once the float valve meets the receptacle, the momentum from the drop fixes the locking ring into place within the groove of float valve and/or an indentation in the float valve receiver.

An embodiment of the present invention includes a system for controlling fluid flow inside a tubular in a wellbore, wherein the system comprises: a tubular, including an internal bore and a latch profile on an inner surface of the tubular, and a receiver that can be positioned in the internal bore of the tubular at the latch profile, so that the tubular and the receiver form a unit for insertion into the wellbore, wherein an interior of the receiver defines a fluid flow channel, and the fluid flow channel includes an internal taper. The system can further include a float valve for dropping into the wellbore and the receiver, wherein the float valve can include an external taper at an external surface of the float valve, the external taper for abutting against the internal taper of the receiver, so that the float valve in the receiver blocks the fluid flow channel.

In an embodiment, the tubular is a coupling between two segments of a casing string or a drill string. In an embodiment, the float valve is a ball-and-flapper valve. In an embodiment of the system, an external surface of the float valve can include a first recess and a second recess, and the first recess can include a seal for sealing the float valve with the receiver, and the second recess can include a latch ring for locking float valve in a position within the receiver. In an embodiment, an inner surface of the receiver can include an indentation for receiving a portion of the latch ring.

In an embodiment of the system, an external surface of the receiver can include a first groove and a second groove, and the first groove can include a seal for sealing the receiver with the tubular, and the second groove can include a locking ring for locking the receiver in a position within the tubular.

In an embodiment, an inner surface of the latch profile can include an indentation for receiving a portion of the locking ring. In an embodiment, an inner surface of the latch profile includes a no-go shoulder for preventing the receiver from moving past the no-go shoulder.

An embodiment of the present invention includes a method of controlling fluid flow inside a tubular in a wellbore, wherein the method comprises: positioning a receiver within an internal bore of a tubular at a latch profile on an inner surface of the tubular, an interior of the receiver defining a fluid flow channel, and the fluid flow channel including an internal taper. The method can continue with coupling the tubular, with the receiver positioned therein, to a segment of a casing string or a drill string, and inserting the tubular, coupled to the segment of the casing string or the drill string, into the wellbore. The steps of the method can further include subsequently dropping a float valve into the wellbore and the receiver, the float valve including an external taper at an external surface of the float valve, so that the external taper can abut against the internal taper of the receiver, and the float valve in the receiver can block the fluid flow channel.

In an embodiment, the tubular is a coupling between two segments of the casing string or the drill string. In an embodiment, the receiver can be positioned within the internal bore of the tubular via a locking ring on an external surface of the receiver, wherein the locking ring can engage with an indentation at the latch profile of the tubular.

An embodiment of the method can further comprise sealing the receiver within the tubular via a seal between the receiver and the tubular. In an embodiment, the method can comprise sealing the float valve within the receiver via a seal between the float valve and the receiver. An embodiment of the method can further include locking the float valve within the receiver via a latch ring on the float valve, wherein a portion of the latch ring can be received in an indentation on an inner surface of the receiver. In an embodiment, the float valve can be a ball-and-flapper valve. Embodiments of the method can include retrieving the float valve 20 after the float valve 20 is dropped into the receiver 12, and retrieving the float valve 20 via a retrieving tool on a wireline.

The foregoing is intended to give a general idea of the invention, and is not intended to fully define nor limit the invention. The invention will be more fully understood and better appreciated by reference to the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the detailed description of various embodiments usable within the scope of the present disclosure, presented below, reference is made to the accompanying drawings, in which:

FIG. 1A depicts a cross-sectional exploded view of the float valve system.

FIG. 1B depicts the float valve system in exploded view.

FIG. 2 depicts an unexploded side view of a float valve receiver inside float valve housing.

FIG. 3A depicts a cross-sectional view of the float valve as it is lowered by a tool towards the float valve housing.

FIG. 3B depicts an unexploded view of the float valve system as it is lowered by a tool towards the float valve housing.

FIG. 4 depicts a detailed cross-sectional view of the float valve system in which the float valve is seated within the float valve receiver.

One or more embodiments are described below with reference to the listed Figures.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Before describing selected embodiments of the present disclosure in detail, it is to be understood that the present invention is not limited to the particular embodiments described herein. The disclosure and description herein is illustrative and explanatory of one or more presently preferred embodiments and variations thereof, and it will be appreciated by those skilled in the art that various changes in the design, organization, means of operation, structures and location, methodology, and use of mechanical equivalents may be made without departing from the spirit of the invention.

As well, it should be understood that the drawings are intended to illustrate and plainly disclose presently preferred embodiments to one of skill in the art, but are not intended to be manufacturing level drawings or renditions of final products and may include simplified conceptual views to facilitate understanding or explanation. As well, the relative size and arrangement of the components may differ from that shown and still operate within the spirit of the invention.

Moreover, it will be understood that various directions such as “upper”, “lower”, “bottom”, “top”, “left”, “right”, “first”, “second” and so forth are made only with respect to explanation in conjunction with the drawings, and that components may be oriented differently, for instance, during transportation and manufacturing as well as operation. Because many varying and different embodiments may be made within the scope of the concept(s) herein taught, and because many modifications may be made in the embodiments described herein, it is to be understood that the details herein are to be interpreted as illustrative and non-limiting.

The embodiments discussed herein describe a system and method for controlling fluid flow inside well tubulars that are within a wellbore. In these embodiments, a float valve is installed subsequent to and separately from a float housing, which comprises a preexisting receptacle, or receiver, installed within a tubular (e.g., a joint or coupling) of casing. The float housing receptacle is held within the tubular, or casing joint, by a locking ring and seal. The float valve is then dropped into the wellbore and lands on top of the float housing receptacle, enabling a latch ring and seal to fasten around the float valve and seal it within the tubular.

FIG. 1A illustrates a cross-sectional exploded view of a float valve system according to one embodiment, which shows the positional relationships between the system components. The system controls fluid flow inside a tubular 10 in a wellbore 30. The tubular 10 may be a casing coupling that forms a hollow joint between two segments of casing (not shown). The tubular 10, or casing coupling, can act as a float housing for a float valve receiver 12. In this regard, the tubular 10 can include an internal bore 31 into which the float valve receiver 12 can be inserted. The float valve receiver 12 can be inserted into the internal bore 31 of the tubular 10 at the surface (i.e., above-ground), and prior to the casing operations, so that the tubular 10 and the float valve receiver 12 form a unit for insertion into the wellbore 30. As shown, the inner surface of the tubular 10 comprises a latch profile 19, which can aid in holding the float valve receiver 12 in place within the tubular 10, as discussed below.

The float valve receiver 12 may be comprised of a drillable material, which may be selected from any suitable material known in the art. Such materials may include, but are not limited to, ductile metals and non-metallic composites. The float valve receiver 12 comprises an outer diameter 11 and an inner diameter 13. The inner diameter 13 of the float valve receiver 12 defines a fluid flow channel 23 that allows fluid to flow through the tubular 10, and thus the casing string or the drill string. The inner diameter 13 of the float valve receiver 12 can further comprise one or more internal tapers 18 intended to match the contour of one or more external tapers 29 on a float valve 20, as discussed below. The outer diameter 11 of the float valve receiver 12 may comprise a first groove 15 and a second groove 17, which may be sized to accept therein a seal 14 and a locking ring 16, respectively. The seal 14 may be a sealing ring around a circumference of the outer diameter 11. The seal 14 may be formed of an elastic material that compresses upon the insertion of float valve receiver 12 into the tubular 10, thus ensuring a fluid-tight fit. The locking ring 16 may also be formed of an elastic material that compresses upon the insertion of float valve receiver 12 into the tubular 10, to lock the float valve receiver 12 in a position within the tubular 10.

The float valve receiver 12 can be positioned in the internal bore 31 of the tubular 10 at the latch profile 19. For instance, an inner surface of the latch profile 19 can include an indentation for receiving a portion of the locking ring 16 on the float valve receiver 12. When the locking ring 16 expands into the indentation of the latch profile 19, the float valve receiver 12 is held in place within the tubular 10 at a fixed position. Further, the inner surface of the latch profile 19 may include a no-go shoulder 35 that prevents the float valve receiver 12 from moving past the no-go shoulder 35 while in the tubular 10.

As shown, the system includes a float valve 20 that is dropped into the wellbore 30 and the float valve receiver 12. The float valve 20 depicted in FIG. 1A is a ball-and-flapper valve, for example, as described in U.S. patent application Ser. Nos. 14/880,929 and 15/291,788, the contents of which are incorporated herein by reference. However, the float valve 20 is not limited to a ball-and-flapper valve, and it can be appreciated that any suitable float valve may be used with the float valve system. As shown, float valve 20 comprises an outer diameter 21, which matches the contours of the inner diameter 13 of float valve receiver 12, enabling a freely dropped float valve 20 to be guided to the float valve receiver 12. In addition, the external surface 33 of the float valve 20 may comprise a first recess 25 and a second recess 27. The first recess 25 may include a latch ring 24 for locking float valve 20 in a position within the float valve receiver 12. In this regard, the inner diameter 13 of the float valve receiver 12 may include an indentation 37 for receiving a portion of the latch ring 24. The second recess 27 may include a seal 26 for sealing the float valve 20 with the float valve receiver 12. The seal 26 may be a sealing ring around a circumference of the external surface 33.

As shown, the float valve 20 can include one or more external tapers 29 at an external surface 33 of the float valve 20. The one or more external tapers 29 are designed to abut against the internal taper 18 of the float valve receiver 12 when the float valve 20 is latched into place in the float valve receiver 12. In this position within the float valve receiver 12, the float valve 20 blocks the fluid flow channel 23 so that no fluid passes through the float valve receiver 12 and the tubular 10. The float valve 20 may be wireline retrievable. That is, the float valve 20 may be constructed so that it is retrievable from the receiver 12 after the float valve 20 is dropped into the receiver 12. For instance, an internal part of the float valve 20 may include a portion for connecting with a retrieving tool that is attached to a wireline. In an embodiment, the retrieving tool may include one or more clips for snapping onto the internal part of the float valve 20.

FIG. 1B shows an exploded view of the components in the float valve system described in FIG. 1A.

FIG. 2 shows a non-exploded external view of an embodiment of the tubular 10 with the float valve receiver 12 integrally attached therein. The float valve receiver 12 is aligned with the tubular 10 via the latch profile 19, which can align with the locking ring 16 (not visible in FIG. 2) to seat the float valve receiver 12 in place. This represents the only portion of the system which is lowered simultaneously with the casing; everything above the float valve receiver 12 is inserted as part of a separate operation.

Turning now to FIGS. 3A and 3B, an embodiment of the float valve 20 is shown attached to a float valve coupling or tool 40. The float valve 20 and float valve coupling or tool 40 can be connected through a top sub 32 and lowered into the float valve receiver 12 subsequent to casing operations. The sectional side view of FIG. 3A shows the first recess 25 and the second recess 27 within the external surface 33 of the float valve 20. As discussed above, the first recess 25 and the second recess 27 may be sized to retain the latch ring 24 and the seal 26, respectively. The latch ring 24 and the seal 26 are shown in the external side view of FIG. 3B.

In an embodiment of the present invention that includes a method usable for controlling fluid flow inside a tubular 10 in a wellbore 30, the method steps can include positioning the float valve receiver 12 within the internal bore 31 of the tubular 10 at the latch profile 19. The tubular 10, with the float valve receiver 12 positioned therein, can then be coupled to a segment of a casing string or a drill string. Next, the tubular 10, coupled to the segment of the casing string or the drill string, can be inserted into the wellbore 30. Subsequently, the float valve 20 is dropped into the wellbore 30 and the float valve receiver 12, so that the one or more external tapers 29 of the float valve 20 can abut against the internal taper 18 of the float valve receiver 12, and the float valve 20 in the float valve receiver 12 can block the fluid flow channel 23 of the float valve receiver 12. When the float valve 20 is dropped into the wellbore 30 towards the float valve receiver 12, the downward momentum of the float valve 20, when it impacts the float valve receiver 12, compresses the seal 14 between the float valve receiver 12 and the tubular 10, as well as the seal 26 between the float valve 20 and the float valve receiver 12. In this way, the float valve 20 is fixed within float valve receiver 12 (and thus within tubular 10).

The steps of the method can include coupling the tubular 10, with the float valve receiver 12 positioned therein, between two segments of the casing string or the drill string. In addition, the valve receiver 12 can be positioned within the internal bore 31 of the tubular 10 via a locking ring 16 on the external surface 11 of the float valve receiver 12, so that the locking ring 16 can engage with the indentation at the latch profile 19 of the tubular 10. The steps of the method can include locking the float valve 20 within the float valve receiver 12 via the latch ring 24 on the float valve 20, so that a portion of the latch ring 24 is received in the indentation on an inner surface of the float valve receiver 12.

The steps of the method can further comprise retrieving the float valve 20 after the float valve 20 is dropped into the receiver 12. In one embodiment, the float valve 20 is retrieved via a retrieving tool attached on a wireline.

Turning now to FIG. 4, the completed system is shown in cross-section within the tubular 10. The float valve receiver 12, as shown, can surround the entire float valve 20. The latch ring 24 and the seal 26 are shown between the float valve 20 and the float valve receiver 12, and the seal 14 and the locking ring 16 are shown between the float valve receiver 12 and the tubular 10, to provide multiple barriers to fluid flow through the annulus around the float valve 20.

While various embodiments usable within the scope of the present disclosure have been described with emphasis, it should be understood that within the scope of the appended claims, the present invention may be practiced other than as specifically described herein.

Claims

1. A system for controlling fluid flow inside a tubular in a wellbore comprising: a tubular having an internal bore, wherein the tubular comprises a latch profile on an inner surface of the tubular;a receiver comprising a proximal end and a distal end, and positioned in the internal bore of the tubular at the latch profile, wherein the tubular and the receiver form a unit for insertion into the wellbore, wherein an interior of the receiver defines a fluid flow channel, and wherein the fluid flow channel comprises an internal taper at the distal end of the receiver; anda float valve for dropping into the wellbore and the receiver, wherein the float valve comprises a proximal end and a distal end, wherein the float valve comprises an external taper at an external surface on the distal end of the float valve, and wherein the external taper abuts the internal taper of the receiver so that the float valve in the receiver blocks the fluid flow channel.

2. The system according to claim 1, wherein the tubular is a coupling between two segments of a casing string or a drill string.

3. The system according to claim 1, wherein the float valve is a ball-and-flapper valve.

4. The system according to claim 1, wherein an external surface of the receiver comprises a first groove and a second groove, wherein the first groove comprises a seal for sealing the receiver with the tubular, and wherein the second groove comprises a locking ring for locking the receiver in a position within the tubular.

5. The system according to claim 4, wherein an inner surface of the latch profile comprises an indentation for receiving a portion of the locking ring.

6. The system according to claim 1, wherein an inner surface of the latch profile comprises a no-go shoulder for preventing the receiver from moving past the no-go shoulder.

7. The system according to claim 1, wherein the external surface of the float valve comprises a first recess and a second recess, wherein the first recess comprises a seal for sealing the float valve with the receiver, and wherein the second recess comprises a latch ring for locking float valve in a position within the receiver 12.

8. The system according to claim 7, wherein an inner surface of the receiver comprises an indentation for receiving a portion of the latch ring.

9. A method of controlling fluid flow inside a tubular in a wellbore, comprising: positioning a receiver within an internal bore of a tubular at a latch profile on an inner surface of the tubular, wherein the receiver comprises a proximal end and a distal end, wherein an interior of the receiver defines a fluid flow channel, and wherein the fluid flow channel comprises an internal taper at the distal end of the receiver;coupling the tubular, with the receiver positioned therein, to a segment of a casing string or a drill string;inserting the tubular, coupled to the segment of the casing string or the drill string, into the wellbore; andsubsequently dropping a float valve into the wellbore and the receiver, wherein the float valve comprises a proximal end and a distal end, and an external taper at an external surface on the distal end of the float valve, and wherein the external taper abuts the internal taper of the receiver and the float valve in the receiver blocks the fluid flow channel.

10. The method according to claim 9, wherein the tubular is a coupling between two segments of the casing string or the drill string.

11. The method according to claim 9, wherein the receiver is positioned within the internal bore of the tubular via a locking ring on an external surface of the receiver, wherein the locking ring engages with an indentation at the latch profile of the tubular.

12. The method according to claim 9, further comprising sealing the receiver within the tubular via a seal between the receiver and the tubular.

13. The method according to claim 9, further comprising sealing the float valve within the receiver via a seal between the float valve and the receiver.

14. The method according to claim 9, further comprising locking the float valve within the receiver via a latch ring on the float valve, wherein a portion of the latch ring is received in an indentation on an inner surface of the receiver.

15. The method according to claim 9, wherein the float valve is a ball-and-flapper valve.

16. The method according to claim 9, further comprising retrieving the float valve after the float valve is dropped into the receiver.

17. The method according to claim 16, wherein the float valve is retrieved via a retrieving tool on a wireline.