Tubular actuator and method

A tubular actuator includes, a tubular, a support member disposed at the tubular, and a restrictor configured to pass a runnable member when unsupported by the support member and to prevent passage of the runnable member when supported by the support member. The restrictor is movable relative to the support member from an unsupported position to a supported position in response to pressure applied against the runnable member engaged with the restrictor according to a pressure versus time profile.

BACKGROUND

In industries concerned with earth formation boreholes, such as hydrocarbon recovery and gas sequestration, for example, it is not uncommon for various operations to utilize a temporary or permanent plugging device. Sometimes plugging is desirable at a first location, and subsequently at a second location. Moreover, additional plugging locations may also be desired and the plugging can be sequential for the locations or otherwise. Systems employing droppable members, such as balls, for example, are typically used for just such a purpose. The ball is dropped to a ball seat positioned at the desired location within the borehole thereby creating the desired plug.

In applications where the first location is further from surface than the second location, it is common to employ seats with sequentially smaller diameters at locations further from the surface. Dropping balls having sequentially larger diameters allows the ball seat furthest from surface to be plugged first (by a ball whose diameter is complementary to that seat), followed by the ball seat second furthest from surface (by a ball whose diameter is complementary to that seat) and so on.

The foregoing system, however, creates increasingly restrictive dimensions within the borehole that can negatively impact flow therethrough as well as limit the size of tools that can be run into the borehole. Systems and methods that allow operators to plug boreholes at multiple locations without the drawbacks mentioned would be well received in the art.

BRIEF DESCRIPTION

Disclosed herein is a tubular actuator. The tubular actuator includes, a tubular, a support member disposed at the tubular, and a restrictor configured to pass a runnable member when unsupported by the support member and to prevent passage of the runnable member when supported by the support member. The restrictor is movable relative to the support member from an unsupported position to a supported position in response to pressure applied against the runnable member engaged with the restrictor according to a pressure versus time profile.

Further disclosed herein is a method of selectively actuating a tubular actuator. The method includes, running a runnable member within a tubular, engaging a restrictor disposed at the tubular with the runnable member, and doing one of the following. Pressuring up against the engaged runnable member to pressure exceeding a threshold pressure before expiration of a selected period of time and passing the runnable member past the restrictor. Or pressuring up against the engaged runnable member to pressure equal to or less than the threshold pressure for at least the selected period of time thereby moving the restrictor to a supported position and preventing passage of the runnable member.

Further disclosed herein is a tubular actuator. The tubular actuator includes, a restrictor positionable within a tubular relative to a support member between an unsupported position where passage of a runnable member is facilitated, and a supported position where passage of the runnable member is prevented.

DETAILED DESCRIPTION

Embodiments of a tubular actuator disclosed herein allow an operator to selectively actuate or selectively pass each of one or more of the tubular actuators disposed within a tubular. The operator runs a runnable member to engage with the tubular actuator(s) and then either pressures up to above a latch pressure to perform an actuation process or to below the latch pressure to allow the runnable member to pass through the tubular actuator thereby avoiding performance of an actuation.

Referring toFIG. 1, an embodiment of the tubular actuator disclosed herein is illustrated generally at10. The tubular actuator10includes, a restrictor14having a body18, which is movable within a tubular22during actuation, and a seat26that is sealingly engagably receptive of a runnable member28, illustrated herein as a ball. The seat26is selectively defeatable such that the ball28is able to pass as will be explained in detail below. The seat26in this embodiment is attached to an end30of a sleeve34. The sleeve34is slidably sealingly engaged with the body18by seals38, illustrated herein as o-rings, at both the end30and an opposing end42thereby creating a chamber46, defined by the annular space between the body18and the sleeve34and bound at the ends30,42by the two o-rings38, that is fluidically isolated. The chamber46is divided into two sub-chambers46A and46B by a shoulder50extending from the body18and slidably sealingly engaged with the sleeve34. One or more ports54in the shoulder50fluidically connect the sub-chambers46A and46B to one another. As such, movement of the sleeve34relative to the body18causes fluid, such as hydraulic oil, for example, housed within the chamber46to be pumped from one of the sub-chambers46A,46B to the other of the sub-chambers46A,46B through the port(s)54. The foregoing structure allows an operator to control a time for the sleeve34to move through a full stroke by adjustment of the size and number of the port(s)54used. Regardless of whether the sleeve34has been fully stroked, a reduction in pressure can allow the sleeve34to move back to its original position under the influence of a biasing member56, illustrated herein as a compression spring, compressingly engaged between the sleeve34and the body18.

Referring toFIG. 2, the seat26becomes defeatable once the sleeve34has fully stroked relative to the body18. In this embodiment the seat26includes a plurality of seat sections58that are radially expandable to allow passage of the ball28when the seat sections58are not supported by an inner radial surface62of the body18. Since the seat sections58are radially supported by the inner radial surface62at all relative locations of the sleeve34and body18other than the fully stroked position (wherein the seat sections58are able to move into an inner recess66), it is only when the sleeve34is in the fully stroked position, as illustrated inFIG. 2, that the ball28is allowed to pass. Moving the sleeve34to the fully stroked position can be done by applying pressure to a ball28seated against the seat26, thereby urging the sleeve34to move.

Movement of the sleeve34relative to the body18, however, is prevented if pressure applied to the seated ball28exceeds a latch pressure defined as the pressure at which latching occurs between the sleeve34, (or the seat26itself) and the body18. This latching can be through an increase in frictional engagement between the sleeve34, the seat26, or both, and the inner radial surface62of the body18for example. Alternate latching engagement mechanisms are contemplated but not disclosed in further detail herein.

Referring toFIG. 3, when pressure exceeding the latch pressure is supplied prior to the sleeve34completing a full stroke, the sleeve34becomes longitudinally fixed relative to the body18. Once the sleeve34is latched to the body18, all of the forces generated by pressure against the seated ball28are transferred through the body18to the tubular22. This force can be used to move the body18relative to the tubular22in an actuating event. For example, the body18may block one or more ports70in the tubular22while in its original position (FIGS. 1 and 2), and then effectively open the port(s)70by aligning them with one or more ports74in the body18after the body18has moved (FIGS. 3 and 4). Such an actuation can be used to provide selective access to a formation outside the tubular22for fracturing, for example, in a downhole hydrocarbon or sequestration application. Additionally, one or more releasable members78, shown herein as shear screws, may longitudinally attach the body18to the tubular22until a selectable load, such as by a threshold pressure, is applied therebetween, to prevent inadvertent actuation of the tubular actuator10.

Referring toFIG. 4, the ball28may still be allowed to pass after the tubular actuator10has been actuated. To do so, one would simply reduce the pressure after the actuation is completed to pressure below the latch pressure. In so doing the sleeve34becomes unlatched from the body18and permits the sleeve34to move relative to the body18. After full stroking of the sleeve34has occurred the seat sections58can expand radially into the inner recess66and allow the ball28to pass therethrough, as is illustrated inFIG. 4. After passage of the ball28the biasing member56can return the sleeve34to its original position with respect to the body18, thereby being reset to a position engagable by another of the balls28.

Positioning a plurality of the tubular actuators10along the tubular22allows an operator to selectively actuate any one of the plurality of actuators10regardless of the number of actuators10between it and the origin of entry for the balls28.

Referring toFIGS. 5-9, an alternate embodiment of a tubular actuator disclosed herein is illustrated generally at110. The tubular actuator110includes, a restrictor114having a body118, which is movable within a tubular122, and at least one support member130, with multiple support members130being illustrated in this embodiment. The restrictor114also has a seat126that is sealingly engagably receptive to a runnable member128, illustrated herein as an extrudable ball. The seat126is attached to an end of a sleeve134and is movable within the body118. The actuator110is similar to the actuator10in that chambers46A and46B are fluidically connected to each other by port(s)54that control a rate at which fluid is able to flow between the two chambers46A and46B. This rate of fluid flow controls a rate of movement of the sleeve134with respect to the body118. Unlike the actuator10, however, wherein passage of the runnable member28was prevented until the sleeve34had been fully stroked, in the actuator110the runnable member128is only allowed to pass the restrictor114prior to full stroking of the sleeve34. This passage is due to extrusion of the runnable member128by the seat126if pressure exceeding a threshold pressure is applied thereagainst prior to repositioning of the support members130.

Referring toFIG. 6, the sleeve134as illustrated is in a fully stroked position. As such, ends138of seat126have contacted cams142on each of the support members130causing the support members130to rotate to the support position shown inFIG. 7thereby presenting support surfaces146to the runnable member128. Consequently, further increases in pressure against the engaged runnable member128will urge the body118to move relative to the tubular122(to the position shown inFIG. 8), instead of extruding the runnable member128past the restrictor114. The foregoing structure allows an operator, by selectively controlling a pressure versus time profile, to selectively pass the runnable member128beyond the restrictor114or to selectively move the restrictor114to a supported position to thereby allow actuational movement of the body118relative to the tubular122.

The actuator110is further configured to allow passage of the runnable member128even after the support members130have rotated and supported the runnable member128. To do so requires the pressure against the runnable member128to be decreased to a level below a biasing force of the biasing member56that, as described with reference toFIG. 4, biases the sleeve134to return to its original position with respect to the body118. Doing so in this embodiment positions the restrictor114in a position to be passable or actuatable through engagement with another of the runnable members128.

The embodiment ofFIGS. 5-9is also configured to open ports150in the tubular122by aligning ports154in the body118, thereby providing fluidic communication between an inside and an outside of the tubular122. Such fluidic communication is useful for production of hydrocarbons, for example, in an application directed to hydrocarbon recovery. Additionally, such fluidic communication allows for fracturing of a downhole formation through pressurization of the formation through the open ports150,154.

Referring toFIGS. 10-12, an alternate embodiment of a tubular actuator is illustrated generally at210. The actuator210is similar to the actuator110in that a runnable member228is passable thereby in response to a threshold pressure being provided against the runnable member228prior to expiration of a time delay, and whereas, increases in pressure beyond the threshold pressure only after the time delay has expired will not result in passage of the runnable member228thereby. The actuator210differs from the actuator110in that the runnable member228does not deform and extrude through a restrictor214, as does the runnable member128by the restrictor114. Instead, a seat226of the restrictor214repositions, or deforms as is illustrated in this embodiment, to allow passage of the runnable member228(the runnable member228remaining in a nondeformed condition).

Structurally, the seat226of the restrictor214is cantilevered on fingers232that can flex radially outwardly when loads due to pressure exceeding a threshold pressure are applied against the runnable member228. Additionally, the seat226can be mounted on a sleeve with fluidic chambers to control movement of the seat226relative to a tubular222as is done in the above embodiments, additionally, other means of damping movement can be employed. A support member230positioned downstream of the restrictor214, as defined by the direction of pressure supplied against the runnable member228, is configured to support the fingers232from outward radial expansion if the restrictor214moves into overlapping engagement with the support member230prior to passage of the runnable member228by the restrictor214. Support of the fingers232by the support member230prevent radial outward deflection of the fingers232that is necessary to pass the runnable member228by the restrictor214. As such, an operator can selectively pass the runnable member228by the restrictor214or have the runnable member228actuationally engage with the restrictor214by selectively controlling a pressure versus time profile of the pressure applied to the runnable member228once seated on the seat226.

Actuation of the actuator210can be accomplished by pressuring up to pressure greater than the threshold pressure against the runnable member228seated against the seat226after the restrictor214has moved into supporting engagement with the support member230. One or more releasable members236, illustrated herein as shear screws, can releasable attach the actuator210to the tubular222until a sufficient load is applied to release the releasable members236, thereby allowing the actuator210to actuate relative to the tubular222.