Patent Description:
Packer assemblies are used in bores, such as wellbores or pipelines, to create temporary or permanent seals within the bores. A packer assembly may include one or more packing element. Typically, a packing element may be made out of a deformable material, such as an elastomer, to a prescribed initial length and initial outer diameter. The packing element may be set in a bore by the application of axial compression, thereby reducing the length of the packing element, and causing the packing element to deform radially outward into sealing contact with the surrounding bore.

For ease of installation in a bore, it may be desirable to run a packing element having an initial outer diameter significantly smaller than the inner diameter of the bore. In some instances, the packing element may have to fit through a restriction in the bore while being installed to the desired location in the bore. Such a situation may compromise the eventual utility of the packing element because generally, the greater the ratio of bore diameter to the initial outer diameter of the packing element, the lower the pressure sealing capability of the packing element when set in the bore. Hysteresis of deformable materials, such as elastomers, may adversely affect retrieval of a packing element from a bore, especially if retrieval involves passing the used packing element through a restriction.

Many operations conducted within a bore, such as a wellbore or a pipeline, require an anchor to be established within the bore, for example to secure tubing and equipment within a wellbore and to establish a force reaction point for other wellbore operations, such as setting packers, bridge plugs, anchoring other tools, and the like. Many anchors include slip systems that typically include a number of slip members having gripping teeth. Setting such an anchor involves moving the slip members radially outward into engagement with a bore wall. Cone based slip systems may include a cone that is moved axially relative to one or more slip members to radially move and support the slips in engagement with a bore wall. Conventional slip systems are limited in how far the slip members can move between the retracted and extended positions. Other slip systems have poor load ratings when the slip members are fully extended from a relatively small diameter to a relatively large diameter.

There is a need for some tools, such as packers and bridge plugs, to have packing elements and slip systems to be capable of undergoing transitions from a relatively small diameter to a relatively large diameter without compromising sealing or anchoring capabilities.

<CIT> discloses a downhole tool held in a wellbore with a unidirectional slip and a bidirectional slip. The bi-directional slip has a slip frame and at least two slip banks. The slip frame comprises a center ring and a plurality of slats extending longitudinally uphole and downhole from the center ring and spaced radially about the center ring so as to define at least two pairs of slots. Each pair of slots has a first slot extending longitudinally uphole from the center ring and a second slot extending longitudinally downhole from the center ring. The slip banks have a first gripping bank, a second gripping bank and a groove between the first gripping bank and second gripping bank. <CIT> discloses a retrievable well lock for use within a subterranean tubular member that has a packing assembly having a substantially elastomeric sleeve which may be axially compressed into an expanded diameter condition against the interior surface of a surrounding tubing string. <CIT> discloses an expandable packer or anchor featuring a gripping device integral to or mounted in a sleeve over the mandrel.

The present invention is defined herein in accordance with the appended claims.

In one embodiment, a slip assembly includes a slip mandrel and a first cone assembly coupled to the slip mandrel. The first cone assembly includes a first base cone and a first extension ramp coupled to the first base cone. The first extension ramp is movable between a radially retracted position and a radially extended position, and is biased toward the radially retracted position by a first biasing member. The slip assembly further includes a slip member disposed adjacent the first base cone. The slip member is configured to slide between retracted and extended positions along an outer surface of the first base cone and along an outer surface of the first extension ramp.

A downhole tool may include a central mandrel, a packer assembly disposed about the central mandrel, and the slip assembly referred to above disposed about the central mandrel.

In another embodiment, a method of operating a slip assembly includes moving a first support cone of a first cone assembly relative to a first extension ramp of the first cone assembly, thereby causing the first extension ramp to pivot from a radially retracted position to a radially extended position. The method further includes moving a second support cone of a second cone assembly relative to a second extension ramp of the second cone assembly, thereby causing the second extension ramp to pivot from a radially retracted position to a radially extended position. The method further includes moving the first cone assembly towards the second cone assembly, thereby moving a slip member disposed between the first and second cone assemblies from a radially retracted position to a radially extended position by sliding a first end of the slip member along an outer surface of the first extension ramp and sliding a second end of the slip member along an outer surface of the second extension ramp.

The present disclosure concerns packer assemblies and slip assemblies that may be incorporated into tools for use in a bore, such as a wellbore, a pipeline, and the like. Tools incorporating the packer and/or slip assemblies of the present disclosure may include wellbore packers, hangers, whipstock anchors, and the like. Another example tool is a bridge plug.

<FIG> is a general external view of a bridge plug incorporating a packer assembly and a slip assembly of the present disclosure. The bridge plug <NUM> may be configured to transition from a running configuration, in which the bridge plug <NUM> may be installed in a bore, to a set configuration, in which the bridge plug <NUM> may be fixed in place within the bore. In some embodiments, the bridge plug <NUM> may be configured to transition from the set configuration to a released configuration, in which the bridge plug <NUM> may be freed from the location in the bore in which the bridge plug <NUM> had been fixed. The bridge plug <NUM> may be in a configuration suitable for retrieval from the bore when in the running and in the released configurations.

The bridge plug <NUM> may have a setting tool adaptor <NUM>. The setting tool adaptor <NUM> may be sized such that a sleeve <NUM> (shown as dashed lines) of a setting tool may fit around the setting tool adaptor <NUM> and may bear against an upper end of a setting sleeve <NUM>.

The bridge plug <NUM> may have a packer assembly <NUM>. The packer assembly <NUM> may have a packing element <NUM> that may create a seal in the bore. The packing element <NUM> may create the seal when the packer assembly <NUM> is transitioned from a running configuration, in which the packing element <NUM> is not in <NUM> degree circumferential contact with an inner wall of the bore, to a set configuration in which the packing element <NUM> is at least substantially in <NUM> degree circumferential contact with the inner wall of the bore. In some embodiments, the packer assembly <NUM> may be transitioned from the set configuration to a released configuration, in which the packing element <NUM> is not in <NUM> degree circumferential contact with the inner wall of the bore. In some embodiments, the packing element <NUM> may have a first maximum outer diameter when in the running configuration, a second larger maximum outer diameter when in the set configuration, and a third maximum outer diameter when in the released configuration. In some embodiments, the third maximum outer diameter is substantially the same as the first maximum outer diameter. The packer assembly <NUM> may be incorporated into a tool such as a wellbore packer or a bridge plug <NUM>.

The bridge plug <NUM> may have a slip assembly <NUM>. The slip assembly <NUM> may be configured to transition from a running configuration, in which the slip assembly <NUM> may be installed in the bore, to a set configuration, in which the slip assembly <NUM> may be fixed in place within the bore. The slip assembly <NUM> may be configured to transition from the set configuration to a released configuration, in which the slip assembly <NUM> may be freed from the location in the bore in which the slip assembly <NUM> had been fixed. The slip assembly <NUM> may be in a configuration suitable for retrieval from the bore when in the running and in the released configurations.

<FIG>show the bridge plug <NUM> of <FIG> in further detail when the bridge plug <NUM> is in the running configuration. The bridge plug <NUM> is shown having a setting tool adaptor <NUM> that may be configured to couple to, and to be manipulated by, a setting tool. The setting tool adaptor <NUM> may have a fishing neck <NUM> that is sized and shaped to facilitate attachment of a fishing tool, retrieval tool, or the like. The fishing neck <NUM> may be coupled to a release sleeve <NUM> by one or more fastener <NUM>, such as a latch, locking dog, collet, snap ring, shear ring, shear screw, shear pin, or the like. In some embodiments, the fastener <NUM> may temporarily inhibit relative axial movement between the fishing neck <NUM> and the release sleeve <NUM>. The release sleeve <NUM> may be coupled to an adaptor body <NUM> that has one or more side port <NUM>. The adaptor body <NUM> may be coupled to a central mandrel <NUM> that may extend through the bridge plug <NUM>. The fishing neck <NUM> may be coupled to an equalization mandrel <NUM> that may extend through the central mandrel <NUM>. The equalization mandrel <NUM> may have one or more side port <NUM>.

Below the setting tool adaptor <NUM>, the central mandrel <NUM> may extend through a setting sleeve <NUM>, and be coupled to the setting sleeve <NUM> by a lock ring <NUM>. The lock ring <NUM> may include ratchet teeth <NUM> that are configured to engage with corresponding ratchet teeth <NUM> on the central mandrel <NUM>. The lock ring <NUM> may be configured to permit the setting sleeve <NUM> to move downwards with respect to the central mandrel <NUM>, but prevent the setting sleeve <NUM> from moving upwards with respect to the central mandrel <NUM>. Additionally, the central mandrel <NUM> may be coupled to the setting sleeve <NUM> by one or more fastener <NUM>, such as a latch, locking dog, collet, snap ring, shear ring, shear screw, shear pin, or the like. In some embodiments, the fastener <NUM> may temporarily inhibit relative axial movement between the central mandrel <NUM> and the setting sleeve <NUM>. In some embodiments, the fastener <NUM> may be engaged with a stop ring <NUM> on the central mandrel <NUM>.

One or more key <NUM> may couple the setting sleeve <NUM> and the central mandrel <NUM>. Each key <NUM> may protrude into a corresponding slot <NUM> on the central mandrel <NUM>. The interaction between each key <NUM> and corresponding slot <NUM> may inhibit relative rotation between the setting sleeve <NUM> and the central mandrel <NUM>. Thus, a remedial milling operation to disintegrate the lock ring <NUM> may be facilitated, if required, without incurring relative rotation between the setting sleeve <NUM> and the central mandrel <NUM>.

The bridge plug <NUM> may include a packer assembly <NUM>, such as that shown in <FIG> and in <FIG>. The setting sleeve <NUM> may be coupled to the packer assembly <NUM>. The packer assembly <NUM> may include a packer mandrel <NUM> and a packing element <NUM> disposed about the packer mandrel <NUM>. The setting sleeve <NUM> may be coupled to the packer mandrel <NUM>. The packer mandrel <NUM> may be disposed about the central mandrel <NUM>. A seal member <NUM> may provide a seal between the central mandrel <NUM> and the packer mandrel <NUM>. The packer assembly <NUM> may include an upper recovery sleeve <NUM> disposed about the packer mandrel <NUM> and extending between the packer mandrel <NUM> and an upper end <NUM> of the packing element <NUM>. The upper recovery sleeve <NUM> may have an upper recovery profile <NUM> embedded within the packing element <NUM>. The upper recovery profile <NUM> may include an annular projection <NUM> within the packing element <NUM>. The annular projection <NUM> may be bonded to the packing element <NUM>.

The packer assembly <NUM> may include a lower recovery sleeve <NUM> disposed about the packer mandrel <NUM> and extending between the packer mandrel <NUM> and a lower end <NUM> of the packing element <NUM>. The lower recovery sleeve <NUM> may have a lower recovery profile <NUM> embedded within the packing element <NUM>. The lower recovery profile <NUM> may include an annular projection <NUM> within the packing element <NUM>. The annular projection <NUM> may be bonded to the packing element <NUM>.

The packer assembly <NUM> may include an upper backup assembly <NUM> and a lower backup assembly <NUM>. The upper backup assembly <NUM> may be disposed about the upper recovery sleeve <NUM>. The upper backup assembly <NUM> may be configured to limit upward axial extension of the packing element <NUM>. The lower backup assembly <NUM> may be disposed about the lower recovery sleeve <NUM>. The lower backup assembly <NUM> may be configured to limit downward axial extension of the packing element <NUM>.

The upper backup assembly <NUM> may include an upper inner backup sleeve <NUM>. The upper inner backup sleeve <NUM> may have an annular shoulder <NUM>, and may be movable with respect to the upper recovery sleeve <NUM>. The upper backup assembly <NUM> may include an upper outer backup sleeve <NUM> disposed about the upper inner backup sleeve <NUM>. The upper outer backup sleeve <NUM> may have an annular shoulder <NUM>, and may be movable with respect to the upper inner backup sleeve <NUM>. A biasing member <NUM>, such as a spring or a mass of resilient deformable material, such as an elastomer, may be disposed between the annular shoulder <NUM> of the upper inner backup sleeve <NUM> and the annular shoulder <NUM> of the upper outer backup sleeve <NUM>.

The upper backup assembly <NUM> may include an upper backup ring assembly <NUM>. The upper backup ring assembly <NUM> may be coupled to an upper backup support <NUM>. The upper backup support <NUM> may be coupled to the upper inner backup sleeve <NUM> and disposed at least partially inside the upper outer backup sleeve <NUM>. The upper backup support <NUM> and the upper backup ring assembly <NUM> may move with the upper inner backup sleeve <NUM> relative to the upper outer backup sleeve <NUM>. A key <NUM> may be coupled to the upper backup support <NUM>, and may protrude into a keyway <NUM> of the upper outer backup sleeve <NUM>. Relative movement between the upper backup support <NUM> and the upper outer backup sleeve <NUM> may be constrained by the interaction between the key <NUM> and the keyway <NUM>.

The upper backup ring assembly <NUM> may be configured to enclose an outer surface <NUM> of the upper end <NUM> of the packing element <NUM>. The upper backup ring assembly <NUM> may include an inner backup ring <NUM> and an outer backup ring <NUM> adjacent the inner backup ring <NUM>. The inner backup ring <NUM> may have fingers <NUM> separated by slots <NUM>, and the fingers <NUM> may be disposed adjacent the outer surface <NUM> of the upper end <NUM> of the packing element <NUM>. The outer backup ring <NUM> may have fingers <NUM> separated by slots <NUM>, and the fingers <NUM> may be disposed such that each finger <NUM> of the outer backup ring overlaps with a corresponding slot <NUM> of the inner backup ring <NUM>.

The lower backup assembly <NUM> may include a lower inner backup sleeve <NUM>. The lower inner backup sleeve <NUM> may have an annular shoulder <NUM>, and may be movable with respect to the lower recovery sleeve <NUM>. The lower backup assembly <NUM> may include a lower outer backup sleeve <NUM> disposed about the lower inner backup sleeve <NUM>. The lower outer backup sleeve <NUM> may have an annular shoulder <NUM>, and may be movable with respect to the lower inner backup sleeve <NUM>. A biasing member <NUM>, such as a spring or a mass of resilient deformable material, such as an elastomer, may be disposed between the annular shoulder <NUM> of the lower inner backup sleeve <NUM> and the annular shoulder <NUM> of the lower outer backup sleeve <NUM>.

The lower backup assembly <NUM> may include a lower backup ring assembly <NUM>. The lower backup ring assembly <NUM> may be coupled to a lower backup support <NUM>. The lower backup support <NUM> may be coupled to the lower inner backup sleeve <NUM> and disposed at least partially inside the lower outer backup sleeve <NUM>. The lower backup support <NUM> and the lower backup ring assembly <NUM> may move with the lower inner backup sleeve <NUM> relative to the lower outer backup sleeve <NUM>. A key <NUM> may be coupled to the lower backup support <NUM>, and may protrude into a keyway <NUM> of the lower outer backup sleeve <NUM>. Relative movement between the lower backup support <NUM> and the lower outer backup sleeve <NUM> may be constrained by the interaction between the key <NUM> and the keyway <NUM>.

The lower backup ring assembly <NUM> may be configured to enclose an outer surface <NUM> of the lower end <NUM> of the packing element <NUM>. The lower backup ring assembly <NUM> may include an inner backup ring <NUM> and an outer backup ring <NUM> adjacent the inner backup ring <NUM>. The inner backup ring <NUM> may have fingers <NUM> separated by slots <NUM>, and the fingers <NUM> may be disposed adjacent the outer surface <NUM> of the lower end <NUM> of the packing element <NUM>. The outer backup ring <NUM> may have fingers <NUM> separated by slots <NUM>, and the fingers <NUM> may be disposed such that each finger <NUM> of the outer backup ring <NUM> overlaps with a corresponding slot <NUM> of the inner backup ring <NUM>.

As shown in <FIG> and <FIG>, the packing element <NUM> may be manufactured as a single piece of packing material, such as an elastomer. The single piece may be referred to as a unitary structure. During manufacture, the elastomer may be built up in layers, such as by wrapping one or more sheet around a form, and then cured to form the unitary structure. In some embodiments, the packing element <NUM> may incorporate more than one grade of elastomeric material in the unitary structure. For example, the packing element may include elastomeric material of <NUM> durometer and elastomeric material of <NUM> durometer. In some embodiments, the packing element <NUM> may incorporate non-elastomeric materials in the unitary structure. For example, the unitary structure of the packing element <NUM> may include resilient fibers, such as aramid fibers. In some embodiments, the packing element <NUM> may include one or more garter spring embedded in the unitary structure. Thus, in embodiments in which the packing element <NUM> is a unitary structure, the unitary structure need not be homogenous. Furthermore, the unitary structure may include different types of materials, as described above.

In some embodiments, one or more filler ring <NUM> may be disposed around the packer mandrel <NUM>, between the packer mandrel <NUM> and the packing element <NUM>. The one or more filler ring <NUM> may be bonded to the packing element <NUM>. The one or more filler ring <NUM> may be movable on the packer mandrel <NUM>. In some embodiments, the one or more filler ring <NUM> may be made out of a rigid material, such as steel.

The packer assembly <NUM> may have a lower boost mechanism. The lower boost mechanism may be configured to act on the lower backup assembly <NUM> after the packing element <NUM> has been set in a bore. The lower boost mechanism may apply an upwardly-directed force on the lower backup assembly <NUM> when a pressure in the bore below the packing element <NUM> exceeds a pressure in the bore above the packing element <NUM>.

The lower boost mechanism may include a boost housing <NUM> coupled to a boost housing extension <NUM>. One end of the boost housing extension <NUM> may be coupled to the lower inner backup sleeve <NUM>. The other end of the boost housing <NUM> may be coupled to a boost mandrel <NUM>, which may also be coupled to another component of the bridge plug <NUM>, such as a slip assembly <NUM>. As illustrated in <FIG>, and for the benefit of further description, in some embodiments, the boost mandrel <NUM> may be coupled to a slip assembly skirt <NUM>. The coupling between the boost mandrel <NUM> and the slip assembly skirt <NUM> may include a lock ring <NUM>. The lock ring <NUM> may include ratchet teeth <NUM> that are configured to engage with corresponding ratchet teeth <NUM> on the boost mandrel <NUM>. The lock ring <NUM> may be configured to permit the boost mandrel <NUM> to move upwards with respect to the slip assembly skirt <NUM>, but prevent the boost mandrel <NUM> from moving downwards with respect to the slip assembly skirt <NUM>.

The central mandrel <NUM> may extend through the lower boost mechanism, and may have one or more side port <NUM> that fluidically couples an interior of the central mandrel <NUM> with an exterior of the central mandrel <NUM>. Seal members <NUM>, <NUM> either side of the port may provide a seal between the central mandrel <NUM> and the boost housing <NUM> and the boost mandrel <NUM>, respectively. Pressure in the bore above the packing element <NUM> when the packing element <NUM> is set in the bore may be communicated through the one or more side port <NUM> in the adaptor body <NUM>, between the equalization mandrel <NUM> and the central mandrel <NUM>, and through the one or more side port <NUM> of the central mandrel <NUM> into the interior of the boost housing <NUM>. Pressure in the bore below the packing element <NUM> may be communicated around the lock ring <NUM> between the boost mandrel <NUM> and the slip assembly skirt <NUM> and into the interior of the boost mandrel <NUM>.

Thus, a pressure differential may exist across the seal member <NUM> between the central mandrel <NUM> and the boost mandrel <NUM>. If the pressure in the bore below the packing element <NUM> is greater than the pressure in the bore above the packing element <NUM>, the pressure differential across the seal member <NUM> will result in a net upward force on the boost mandrel <NUM>. The net upward force may be transmitted through the boost housing <NUM> and boost housing extension <NUM> to the lower backup assembly <NUM>, and may result in the lower backup assembly <NUM> applying an upward boost force on the packing element <NUM> that is additional to the force applied during an initial setting of the packing element <NUM>. A corresponding upward movement of the lower backup assembly <NUM>, boost housing extension <NUM>, boost housing <NUM>, and boost mandrel <NUM> may be accommodated by the ratchet teeth <NUM> of the lock ring <NUM> and the ratchet teeth <NUM> of the boost mandrel <NUM>, and hence the boost mandrel <NUM> may move upward with respect to the slip assembly <NUM>. Since the ratchet teeth <NUM> of the lock ring <NUM> and the ratchet teeth <NUM> of the boost mandrel <NUM> inhibit the boost mandrel <NUM> from moving downwards with respect to the slip assembly <NUM>, the boost force applied to the packing element <NUM> may be sustained even if the pressure differential that caused the exertion of the boost force is subsequently reduced, or eliminated, or reversed.

The packer assembly <NUM> may have an upper boost mechanism. The upper boost mechanism may be configured to act on the upper backup assembly <NUM> after the packing element <NUM> has been set in a bore. The upper boost mechanism may apply a downwardly-directed force on the upper backup assembly <NUM> when a pressure in the bore above the packing element <NUM> exceeds a pressure in the bore below the packing element <NUM>.

The upper boost mechanism may include the packer mandrel <NUM>, setting sleeve <NUM>, and the lock ring <NUM> coupling the setting sleeve <NUM> to the central mandrel <NUM>. Pressure in the bore above the packing element <NUM> when the packing element <NUM> is set in the bore may be communicated around the lock ring <NUM> coupling the setting sleeve <NUM> to the central mandrel <NUM>, and into the interior of the setting sleeve <NUM> and against the seal member <NUM> that provides a seal between the packer mandrel <NUM> and the central mandrel <NUM>. Pressure in the bore below the packing element <NUM> may be communicated around the lower backup assembly <NUM>, into the interior of the boost housing extension <NUM>, and between the central mandrel <NUM> and the packer mandrel <NUM> up to the seal member <NUM> that provides a seal between the packer mandrel <NUM> and the central mandrel <NUM>.

Thus, a pressure differential may exist across the seal member <NUM> between the central mandrel <NUM> and the packer mandrel <NUM>. If the pressure in the bore above the packing element <NUM> is greater than the pressure in the bore below the packing element <NUM>, the pressure differential across the seal member <NUM> will result in a net downward force on the packer mandrel <NUM>. The net downward force may be transmitted through the upper backup assembly <NUM>, and may result in the upper backup assembly <NUM> applying a downward boost force on the packing element <NUM> that is additional to the force applied during an initial setting of the packing element <NUM>. A corresponding downward movement of the upper backup assembly <NUM>, packer mandrel <NUM>, and setting sleeve <NUM> may be accommodated by the ratchet teeth <NUM> of the lock ring <NUM> and the ratchet teeth <NUM> of the central mandrel <NUM>, and hence the setting sleeve <NUM> may move downward with respect to the central mandrel <NUM>. Since the ratchet teeth <NUM> of the lock ring <NUM> and the ratchet teeth <NUM> of the central mandrel <NUM> inhibit the setting sleeve <NUM> from moving upwards with respect to the central mandrel <NUM>, the boost force applied to the packing element <NUM> may be sustained even if the pressure differential that caused the exertion of the boost force is subsequently reduced, or eliminated, or reversed.

The bridge plug <NUM> may include a slip assembly <NUM>, such as that shown in <FIG> and in <FIG>. A slip setting ring <NUM> may be disposed around the central mandrel <NUM> within the boost housing extension <NUM>. The slip setting ring <NUM> may be movable on the central mandrel <NUM>, but temporarily coupled to the boost housing extension <NUM> by one or more fastener <NUM>, such as a latch, locking dog, collet, snap ring, shear ring, shear screw, shear pin, or the like. As described below, the slip setting ring <NUM> and the one or more fastener <NUM> may enable an axial force from the packer mandrel <NUM> to be transmitted through the boost housing extension <NUM> and boost mandrel <NUM> in order to set slip member(s) <NUM> of the slip assembly <NUM>. The slip member(s) <NUM> may be actuated into contact with a surrounding bore by interaction with an upper cone assembly <NUM> and a lower cone assembly <NUM>.

As described above, <FIG> show the boost mandrel <NUM> coupled to a slip assembly skirt <NUM> of the upper cone assembly <NUM>. The slip assembly skirt <NUM> may be coupled to an upper support cone <NUM>. In some embodiments, the slip assembly skirt <NUM> may be formed as part of the upper support cone <NUM>. The upper support cone <NUM> may be disposed around an upper cone sleeve <NUM>. The upper cone sleeve <NUM> may be coupled to an upper base cone <NUM>. In some embodiments, the upper cone sleeve <NUM> may be formed as part of the upper base cone <NUM>. The upper support cone <NUM> may be coupled to the upper cone sleeve <NUM> by a fastener <NUM>, such as a latch, locking dog, collet, snap ring, shear ring, shear screw, shear pin, or the like. One or more key <NUM> may couple the upper support cone <NUM> with the upper cone sleeve <NUM>. Each key <NUM> may protrude into a corresponding slot <NUM> in the upper cone sleeve <NUM>.

The upper support cone <NUM> may have a cone face <NUM>. The upper base cone <NUM> may have a cone face <NUM> and a cone rear <NUM>. One or more upper extension ramp <NUM> may be disposed between the cone face <NUM> of the upper support cone <NUM> and cone rear <NUM> of the upper base cone <NUM>. As shown in <FIG>, the sloped outer surface of the cone face <NUM> of the upper support cone <NUM> may include a concave portion at an interface with each extension ramp <NUM>. The upper extension ramp <NUM> may be pivotably coupled to the upper base cone <NUM> by a pin or hinge <NUM>, and movable between a retracted position (as shown in <FIG>) and an extended position (as shown and described hereinafter). When in the extended position, the upper extension ramp <NUM> may have a ramp surface <NUM> substantially aligned with the cone face <NUM> of the upper base cone <NUM>. The upper extension ramp <NUM> is biased toward the retracted position by a biasing member <NUM>, such as a spring or a mass of resilient deformable material, such as an elastomer. The biasing member <NUM> may be disposed in a slot in an underside of the upper extension ramp <NUM>.

In some embodiments, a maximum outer diameter of the upper support cone <NUM> and a maximum outer diameter of the upper base cone <NUM> do not change when the slip assembly <NUM> transitions between the running, set, and released configurations.

The upper base cone <NUM> may be coupled to a slip mandrel <NUM>. In some embodiments, the slip mandrel <NUM> and upper base cone <NUM> may be formed as a single piece. The slip mandrel <NUM> may extend through the slip assembly <NUM>. The central mandrel <NUM> may extend through the slip mandrel <NUM> and through the slip assembly <NUM>.

A lower cone assembly <NUM> may be disposed on the slip mandrel <NUM>. The lower cone assembly <NUM> may include a lower support cone <NUM> and a lower base cone <NUM>. A lower cone sleeve <NUM> may be coupled to the lower base cone <NUM>. In some embodiments, the lower cone sleeve <NUM> may be formed as part of the lower base cone <NUM>. The lower base cone <NUM> may be coupled to the slip mandrel <NUM> by a fastener <NUM>, such as a latch, locking dog, collet, snap ring, shear ring, shear screw, shear pin, or the like. The lower support cone <NUM> may be disposed around the lower cone sleeve <NUM>. The lower support cone <NUM> may be coupled to the lower cone sleeve <NUM> by a fastener <NUM>, such as a latch, locking dog, collet, snap ring, shear ring, shear screw, shear pin, or the like. One or more key <NUM> may couple the lower support cone <NUM> with the lower cone sleeve <NUM>. Each key <NUM> may protrude into a corresponding slot <NUM> in the lower cone sleeve <NUM>.

The lower support cone <NUM> may have a cone face <NUM>. The lower base cone <NUM> may have a cone face <NUM> and a cone rear <NUM>. One or more lower extension ramp <NUM> may be disposed between the cone face <NUM> of the lower support cone <NUM> and cone rear <NUM> of the lower base cone <NUM>. As shown in <FIG>, the sloped outer surface of the cone face <NUM> of the lower support cone <NUM> may include a concave portion at an interface with each extension ramp <NUM>. The lower extension ramp <NUM> may be pivotably coupled to the lower base cone <NUM> by a pin or hinge <NUM>, and movable between a retracted position (as shown in <FIG>) and an extended position (as shown and described hereinafter). When in the extended position, the lower extension ramp <NUM> may have a ramp surface <NUM> substantially aligned with the cone face <NUM> of the lower base cone <NUM>. The lower extension ramp <NUM> may be biased toward the retracted position by a biasing member <NUM>, such as a spring or a mass of resilient deformable material, such as an elastomer. The biasing member <NUM> may be disposed in a slot in an underside of the lower extension ramp <NUM>.

In some embodiments, a maximum outer diameter of the lower support cone <NUM> and a maximum outer diameter of the lower base cone <NUM> do not change when the slip assembly <NUM> transitions between the running, set, and released configurations.

The slip assembly <NUM> may also include one or more slip member <NUM> disposed between the upper cone assembly <NUM> and the lower cone assembly <NUM>. Each slip member <NUM> may be movable between retracted and extended positions. Each slip member <NUM> may have an upper gripper <NUM> and a lower gripper <NUM>. The upper and lower grippers <NUM>, <NUM> may have outwardly projecting teeth <NUM>. The teeth <NUM> may be configured to penetrate an inner surface of a bore, such as an inner surface of a tubular. Each upper and lower gripper <NUM>, <NUM> may have a sloped inner surface <NUM>, <NUM>. The sloped inner surface <NUM> of the upper gripper <NUM> may be configured to engage and slide against the cone face <NUM> of the upper base cone <NUM>. The sloped inner surface <NUM> of the upper gripper <NUM> is configured to engage and slide against the ramp surface <NUM> of the upper extension ramp <NUM> when the upper extension ramp <NUM> is in the extended position. The sloped inner surface <NUM> of the lower gripper <NUM> may be configured to engage and slide against the cone face <NUM> of the lower base cone <NUM>. The sloped inner surface <NUM> of the lower gripper <NUM> may be configured to engage and slide against the ramp surface <NUM> of the lower extension ramp <NUM> when the lower extension ramp <NUM> is in the extended position.

As shown in <FIG>, <FIG>, <FIG>, and <FIG>, rotational alignment between the upper cone assembly <NUM> and the lower cone assembly <NUM> may be maintained by a key <NUM> in the lower support cone <NUM> that rides within a keyway <NUM> in the lower cone sleeve <NUM> and a keyway <NUM> in the slip mandrel <NUM>.

Each slip member <NUM> may have a shank <NUM> between the upper gripper <NUM> and the lower gripper <NUM>. The shank <NUM> may be at least partially contained within a slip cage <NUM>. The slip cage <NUM> may include a slip cage body <NUM>. One or more retainer <NUM> may be disposed in a radial opening in the slip cage body <NUM>. Each retainer <NUM> may be movable with respect to the slip cage body <NUM> between retracted and extended positions. As best seen in <FIG> and <FIG>, each retainer <NUM> may have a generally "U" shaped profile with one or more flange <NUM> at the ends of the "U" profile. Each retainer <NUM> may have a flange <NUM> at each end of the "U" profile. Each flange <NUM> may be disposed within the slip cage body <NUM>, and may be configured to interact with a corresponding shoulder <NUM> in the slip cage body <NUM>. A biasing member <NUM>, such as a spring or a mass of resilient deformable material, such as an elastomer, may be disposed between each flange <NUM> and each corresponding shoulder <NUM>. Each retainer <NUM> may be biased towards the retracted position by the biasing member(s) <NUM>. The shank <NUM> of each slip member <NUM> may be disposed between the slip cage body <NUM> and a corresponding retainer <NUM>. For example, the shank <NUM> of each slip member <NUM> may be disposed within the "U" profile of a corresponding retainer <NUM>. A biasing member <NUM>, such as a spring or a mass of resilient deformable material, such as an elastomer, may be disposed between each shank <NUM> and the base of each "U" profile of a corresponding retainer <NUM>. Each shank <NUM>, and therefore each slip member <NUM>, may be biased towards the retracted position by each biasing member <NUM>.

When the bridge plug <NUM> transitions from the running configuration to the set configuration, each slip member <NUM> may move from the retracted position to the extended position and each retainer <NUM> may move from the retracted position to the extended position. When the bridge plug <NUM> transitions from the set configuration to the released configuration, each slip member <NUM> may move from the extended position to the retracted position and each retainer <NUM> may move from the extended position to the retracted position.

As shown in <FIG>, <FIG>, and <FIG>, one or more key <NUM> may couple the slip cage <NUM> with the slip mandrel <NUM>. Each key <NUM> may protrude into a corresponding slot <NUM> in the slip mandrel <NUM>. The interaction between each key <NUM> and corresponding slot <NUM> may inhibit relative rotation between the slip cage <NUM> and the slip mandrel <NUM>. Thus, rotational alignment between each slip member <NUM> and each of the upper and lower base cone faces <NUM>, <NUM> plus the upper and lower extension ramps <NUM>, <NUM> may be maintained.

The slip assembly <NUM> may be coupled to one or more mechanism, such as a setting mechanism and/or a release mechanism. The one or more mechanism may be actuated during transition of the bridge plug <NUM> from the running configuration to the set configuration. The one or more mechanism may be actuated during the transition of the bridge plug <NUM> from the set configuration to the released configuration.

The slip assembly <NUM> may be coupled to a release housing <NUM>. The coupling may be between a slip assembly connector <NUM> and the release housing <NUM>. In some embodiments, the slip assembly connector <NUM> may be part of the lower support cone <NUM>. In some embodiments, the slip assembly connector <NUM> may be coupled to the lower support cone <NUM>. With reference to <FIG>, the coupling between the release housing <NUM> and the slip assembly connector <NUM> may include a lock ring <NUM>. The lock ring <NUM> may include ratchet teeth <NUM> that are configured to engage with corresponding ratchet teeth <NUM> on the slip assembly connector <NUM>. The lock ring <NUM> may be configured to permit the slip assembly connector <NUM> to move upwards with respect to the release housing <NUM>, but prevent the slip assembly connector <NUM> from moving downwards with respect to the release housing <NUM>.

Still referring to <FIG>, the slip assembly connector <NUM> may be disposed about a shear sub <NUM>. The shear sub <NUM> may be configured to be a secondary release mechanism that maintains the slip assembly <NUM> in the set configuration until the packer assembly <NUM> has transitioned to the released configuration. The shear sub <NUM> may be coupled to the slip assembly connector <NUM> by a fastener <NUM>, such as a latch, locking dog, collet, snap ring, shear ring, shear screw, shear pin, or the like. The shear sub <NUM> may be disposed about the central mandrel <NUM> such that sufficient space exists for an end of the slip mandrel <NUM> to move into a position between the shear sub <NUM> and the central mandrel <NUM>. The shear sub <NUM> may be configured to couple to the slip mandrel <NUM> during operation of the bridge plug <NUM>. The coupling between the shear sub <NUM> and the slip mandrel <NUM> may include a lock ring <NUM>. The lock ring <NUM> may include ratchet teeth <NUM> that are configured to engage with corresponding ratchet teeth <NUM> on the slip mandrel <NUM>. The lock ring <NUM> may be configured to permit the slip mandrel <NUM> to move downwards with respect to the shear sub <NUM>, but prevent the slip mandrel <NUM> from moving upwards with respect to the shear sub <NUM>.

Continuing with <FIG>, the slip assembly connector <NUM> may be coupled to a lower cone retainer <NUM>. The lower cone retainer <NUM> may be disposed within the release housing <NUM> and about the central mandrel <NUM>. The lower cone retainer <NUM> may be configured to couple to the central mandrel <NUM> during operation of the bridge plug <NUM>. The coupling between the lower cone retainer <NUM> and the central mandrel <NUM> may include a lock ring <NUM>. The lock ring <NUM> may include ratchet teeth <NUM> that are configured to engage with corresponding ratchet teeth <NUM> on the central mandrel <NUM>. The lock ring <NUM> may be configured to permit the central mandrel <NUM> to move upwards with respect to the lower cone retainer <NUM>, but prevent the central mandrel <NUM> from moving downwards with respect to the lower cone retainer <NUM>.

Now referring to <FIG>, the central mandrel <NUM> may extend into the release housing <NUM> and be coupled to a release sub <NUM>. The release sub <NUM> may be contained within the release housing <NUM>. One or more seal member <NUM> may provide a seal between the central mandrel <NUM> and the release sub <NUM>. One or more seal member <NUM> may provide a seal between the release sub <NUM> and the release housing <NUM>. One or more release lug <NUM> may be disposed within one or more corresponding slot <NUM> in the release sub <NUM>. Each release lug <NUM> may have an external profile <NUM> that is configured to engage a corresponding internal profile <NUM> of the release housing <NUM>. The engagement between each release lug <NUM> and the release housing <NUM> may inhibit axial movement of the release sub <NUM> with respect to the release housing <NUM>. The one or more release lug <NUM> may be maintained in engagement with the release housing <NUM> by a support ring <NUM> disposed within the release sub <NUM>. The one or more release lug <NUM> and the support ring <NUM> may be configured as a primary release mechanism that maintains the packer assembly <NUM> in the set configuration until after pressure equalization across the packing element <NUM> has been facilitated.

The equalization mandrel <NUM> may extend through the central mandrel <NUM> into the release sub <NUM>, and may be coupled to a release mandrel <NUM>. The release mandrel <NUM> may extend through the support ring <NUM>. The support ring <NUM> may be configured to couple to the release mandrel <NUM> during operation of the bridge plug <NUM>. The coupling between the support ring <NUM> and the release mandrel <NUM> may include a lock ring <NUM>. The lock ring <NUM> may include ratchet teeth <NUM> that are configured to engage with corresponding ratchet teeth <NUM> on the release mandrel <NUM>. The lock ring <NUM> may be configured to permit the release mandrel <NUM> to move downwards with respect to the support ring <NUM>, but prevent the release mandrel <NUM> from moving upwards with respect to the support ring <NUM>.

The lower end of the release housing <NUM> may be coupled to a ported sub <NUM>. The release mandrel <NUM> may extend into the ported sub <NUM>, and may have one or more side port <NUM> at a lower end. The ported sub <NUM> may have one or more side port <NUM>. As shown in <FIG>, when the bridge plug <NUM> is in the running configuration, the one or more side port <NUM> of the ported sub <NUM> may be obscured by an equalizing sleeve <NUM>. One or more seal member <NUM> may inhibit fluidic communication through the one or more side port <NUM> of the ported sub <NUM> when the equalizing sleeve <NUM> is in the position as shown in <FIG>. As shown in <FIG>, the equalizing sleeve <NUM> may be temporarily held in the position shown in <FIG> by a fastener <NUM>, such as a latch, locking dog, collet, snap ring, shear ring, shear screw, shear pin, or the like.

The ported sub <NUM> may be coupled to a bull nose <NUM>. The bull nose <NUM> may be without any fluid communication ports. One or more seal member <NUM> may inhibit fluidic communication between the ported sub <NUM> and the bull nose <NUM>. In some embodiments, instead of a bull nose <NUM>, the ported sub <NUM> may be coupled to an alternative item of equipment, such as a tubular, a gauge carrier, a logging tool, a perforating gun, etc. As shown in <FIG>, the bull nose <NUM> may be coupled to a debris mandrel <NUM> within the ported sub <NUM>. The debris mandrel <NUM> may extend from the bull nose <NUM> and into the equalizing sleeve <NUM>. To facilitate axial movement of the equalizing sleeve <NUM> so as to uncover the one or more side port <NUM> of the ported sub <NUM>, the equalizing sleeve <NUM> may have one or more relief bore <NUM>. The relief bore <NUM> may prevent the occurrence of a pressure lock as the equalizing sleeve <NUM> moves axially over the debris mandrel <NUM> toward the bull nose <NUM>.

<FIG> show the bridge plug <NUM> in different stages of operation. <FIG> shows the bridge plug <NUM> in a running configuration. <FIG> shows the bridge plug <NUM> during transition to a set configuration in which the slip assembly <NUM> has been set but the packer assembly <NUM> is yet to be set. <FIG> shows the bridge plug <NUM> in the set configuration in which both the slip assembly <NUM> and the packer assembly <NUM> have been set. <FIG> shows the bridge plug <NUM> while still in the set configuration, but actuated to equalize pressure across the packing element <NUM> of the packer assembly <NUM>. <FIG> shows the bridge plug <NUM> during releasing of the packing element <NUM>. <FIG> shows the bridge plug <NUM> having released the packing element <NUM> and commencing release of the slip assembly <NUM>. <FIG> shows the bridge plug <NUM> after having released the slip assembly <NUM> and fully transitioned to a released configuration.

In the following descriptions, any recital of item A moving towards item B is to be interpreted to encompass item A moving towards item B that is itself moving in the same direction as item A, item A moving towards a stationary item B, item B moving towards item A that is itself moving in the same direction as item B, item B moving towards a stationary item A, and both items A and B moving towards each other. Similarly, any recital of item A moving away from item B is to be interpreted to encompass item A moving away from item B that is itself moving in the same direction as item A, item A moving away from a stationary item B, item B moving away from item A that is itself moving in the same direction as item B, item B moving away from a stationary item A, and both items A and B moving away from each other.

Details of the bridge plug <NUM> in the running configuration are shown in <FIG>, and are described above. In an exemplary method, a setting tool (not shown) having a setting tool sleeve <NUM> (<FIG>) may be coupled to the bridge plug <NUM>. The bridge plug <NUM> may be inserted into a bore, such as a wellbore <NUM> (see <FIG> and <FIG>), a pipeline, or the like. Activation of the setting tool may involve applying a tensile axial force (that may be considered as a pull force) to the fishing neck <NUM> while applying a compressive axial force (that may be considered as a push force) to the setting sleeve <NUM>. Activation of the setting tool may result in the bridge plug <NUM> transitioning from the configuration as shown in <FIG> to that shown in <FIG>. Activation of the setting tool may result also in the bridge plug <NUM> transitioning from the configuration as shown in <FIG> to that shown in <FIG>.

Details of the bridge plug <NUM> corresponding to the status shown in <FIG> are shown in <FIG>. The following description highlights at least some of the changes to occur in transitioning from the configuration shown in <FIG>. As illustrated, the setting sleeve <NUM> has moved axially away from the setting tool adaptor <NUM>. Each key <NUM> has slid within a corresponding slot <NUM>, and the ratchet teeth <NUM> of the lock ring <NUM> have moved along, and remain engaged with, the ratchet teeth <NUM> on the central mandrel <NUM>. The one or more fastener <NUM> coupling the central mandrel <NUM> to the setting sleeve <NUM> has been defeated, such as by shearing.

Axial movement of the setting sleeve <NUM> has resulted in axial movement of the packer mandrel <NUM>. The lower end of the packer mandrel <NUM> has engaged the slip setting ring <NUM>. Because the one or more fastener <NUM> coupling the slip setting ring <NUM> to the boost housing extension <NUM> has not been defeated, axial force exerted by the packer mandrel <NUM> on the slip setting ring <NUM> has been transferred to the boost housing extension <NUM> and to the boost housing <NUM>.

The axial force on the boost housing <NUM> has caused the slip assembly <NUM> to transition into the set configuration. The one or more fastener <NUM> coupling the upper support cone <NUM> to the upper cone sleeve <NUM> has been defeated, such as by shearing, and the upper support cone <NUM> has moved towards the upper base cone <NUM>. Each upper extension ramp <NUM> has ridden along the cone face <NUM> of the upper support cone <NUM> from a retracted position to an extended position; each upper extension ramp <NUM> having pivoted about a respective pin or hinge <NUM>. The one or more fastener <NUM> coupling the lower support cone <NUM> to the lower cone sleeve <NUM> has been defeated, such as by shearing, and the lower support cone <NUM> has moved towards the lower base cone <NUM>. Each lower extension ramp <NUM> has ridden along the cone face <NUM> of the lower support cone <NUM> from a retracted position to an extended position; each lower extension ramp <NUM> having pivoted about a respective pin or hinge <NUM>.

Additionally, the one or more fastener <NUM> coupling the lower base cone <NUM> to the slip mandrel <NUM> has been defeated, such as by shearing, and the upper cone assembly <NUM> has moved towards the lower cone assembly <NUM>. The sloped inner surface <NUM> of the upper gripper <NUM> of each slip member <NUM> has ridden along the cone face <NUM> of the upper base cone <NUM> and along a respective upper extension ramp <NUM>. The sloped inner surface <NUM> of the lower gripper <NUM> of each slip member <NUM> has ridden along the cone face <NUM> of the lower base cone <NUM> and along a respective lower extension ramp <NUM>. Hence, each slip member <NUM> has moved radially outwards and into a set position. As illustrated, each retainer <NUM> has also moved radially outwards to an extended position as a result of each slip member <NUM> moving radially outwards. Thus, in embodiments in which the bridge plug <NUM> had been installed in a bore (such as a wellbore or pipeline), the slip assembly <NUM> is now in a set configuration in the bore, and may provide an anchor against further axial movement of the bridge plug <NUM>.

Because the upper cone assembly <NUM> has moved towards the lower cone assembly <NUM>, the lower end of the slip mandrel <NUM> is now engaged with the lock ring <NUM> of the shear sub <NUM>. The relative movement between the upper cone assembly <NUM> and the lower cone assembly <NUM> has been achieved because of the opposing axial tensile and compressive forces applied by the setting tool. The axial tensile force applied to the central mandrel <NUM> has transferred through the release sub <NUM>, the one or more release lug <NUM>, the release housing <NUM>, the slip assembly connector <NUM>, and to the lower support cone <NUM>. The axial compressive force applied to the setting sleeve <NUM> has transferred through the packer mandrel <NUM>, the boost housing extension <NUM>, the boost housing <NUM>, and to the upper support cone <NUM>.

Details of the bridge plug <NUM> corresponding to the status shown in <FIG> are shown in <FIG>. The following description highlights at least some of the changes to occur in transitioning from the configuration shown in <FIG>. As illustrated, the setting sleeve <NUM> has moved further axially away from the setting tool adaptor <NUM>. Each key <NUM> has slid within a corresponding slot <NUM>, and the ratchet teeth <NUM> of the lock ring <NUM> have moved along, and remain engaged with, the ratchet teeth <NUM> on the central mandrel <NUM>.

The lower end of the packer mandrel <NUM> that had engaged the slip setting ring <NUM> applied an axial force in one direction, whereas the boost housing extension <NUM> and boost housing <NUM> were unable to move in the direction of the axial force because the slip assembly <NUM> had been set, thereby providing an anchor resisting movement. Thus, the boost housing extension <NUM> resisted the force applied by the packer mandrel <NUM> through the slip setting ring <NUM>, resulting in the one or more fastener <NUM> coupling the slip setting ring <NUM> to the boost housing extension <NUM> being defeated, such as by shearing. Hence, the upper backup assembly <NUM> has moved towards the lower backup assembly <NUM>, resulting in the packing element <NUM> becoming axially compressed.

As shown in <FIG>, axial compression of the packing element <NUM> has caused the packing element <NUM> to extend radially outwardly. This has caused the inner and outer backup rings <NUM>, <NUM> of the upper backup assembly <NUM> and the inner and outer backup rings <NUM>, <NUM> of the lower backup assembly <NUM> to splay outwards. The upper backup support <NUM> may bear against the outer backup ring <NUM>. The lower backup support <NUM> may bear against the outer backup ring <NUM>. In some embodiments, particularly those in which the one or more filler ring <NUM> is bonded to the packing element <NUM>, the packing element <NUM> may develop one or more external fold <NUM>, as illustrated. In embodiments in which the bridge plug <NUM> had been installed in a bore (such as a wellbore or pipeline), the packer assembly <NUM> is now in a set configuration in the bore, and may provide a seal against an internal wall of the bore.

Details of the bridge plug <NUM> corresponding to the status shown in <FIG> are shown in <FIG>. The following description highlights at least some of the changes to occur in transitioning from the configuration shown in <FIG>. In order to actuate the pressure equalization feature of the bridge plug <NUM>, the fishing neck <NUM> of the setting tool adaptor <NUM> may be engaged by a suitable tool (not shown), such as a setting tool or a retrieval tool. The tool that engages the fishing neck <NUM> may apply an axial compressive force on the fishing neck <NUM>. The axial compressive force may be sufficient to defeat, such as by shearing, the one or more fastener <NUM> coupling the fishing neck <NUM> to the release sleeve <NUM>. As illustrated, the fishing neck <NUM> has moved down towards the adaptor body <NUM>, which has caused the equalization mandrel <NUM> to move downwards with respect to the packer assembly <NUM> and the slip assembly <NUM>.

As illustrated, downward movement of the equalization mandrel <NUM> has caused downward movement of the release mandrel <NUM> with respect to the support ring <NUM>. Ratchet teeth <NUM> on the release mandrel <NUM> have become engaged with corresponding ratchet teeth <NUM> of the lock ring <NUM> in the support ring <NUM>. Additionally, downward axial force applied through the release mandrel <NUM> has caused the fastener <NUM> coupling the equalizing sleeve <NUM> to the ported sub <NUM> to be defeated, such as by shearing. Subsequent downward movement of the equalization mandrel <NUM> has caused downward movement of the equalizing sleeve <NUM> with respect to the ported sub <NUM>, thereby opening fluid communication through the one or more side port <NUM>.

Thus, fluid in the bore below the packing element <NUM> may communicate with fluid in the bore above the packing element <NUM> via the one or more side port <NUM> in the ported sub <NUM>, the one or more side port <NUM> in the release mandrel <NUM>, the release mandrel <NUM>, the equalization mandrel <NUM>, the one or more side port <NUM> in the equalization mandrel <NUM>, and the one or more side port <NUM> in the adaptor body <NUM>. Hence, pressures in the bore above and below the packing element <NUM> may become substantially equalized.

Details of the bridge plug <NUM> corresponding to the status shown in <FIG> are shown in <FIG>. The following description highlights at least some of the changes to occur in transitioning from the configuration shown in <FIG>. In order to commence release of the bridge plug <NUM>, a suitable tool (not shown), such as a setting tool or a retrieval tool, may apply an axial tensile force on the fishing neck <NUM> of the setting tool adaptor <NUM>. As illustrated, the fishing neck <NUM> has moved upwards away from the adaptor body <NUM>, which has caused the equalization mandrel <NUM> to move upwards with respect to the packer assembly <NUM> and the slip assembly <NUM>. A further axial tensile force exerted on the fishing neck <NUM> has transferred through the release sleeve <NUM> and the adaptor body <NUM> to the central mandrel <NUM>.

As illustrated, the central mandrel <NUM> has moved upwards with respect to the setting sleeve <NUM>. The stop ring <NUM> on the central mandrel <NUM> has engaged an inner shoulder <NUM> of the setting sleeve <NUM>, and further upward movement of the central mandrel <NUM> has caused the setting sleeve <NUM> to move upwards. Upward movement of the setting sleeve <NUM> has caused upward movement of the upper inner backup sleeve <NUM>, and that has caused the upper backup assembly <NUM> to become disengaged from the packing element <NUM>. As illustrated, the inner and outer backup rings <NUM>, <NUM> of the upper backup assembly <NUM> may retract at least partially from their splayed outward position.

Upward movement of the upper inner backup sleeve <NUM> also has caused upward movement of the upper recovery sleeve <NUM> via engagement with a stop ring <NUM> on the upper recovery sleeve <NUM>. As illustrated, interaction between the upper recovery profile <NUM> of the upper recovery sleeve <NUM> and the packing element <NUM> may cause the packing element <NUM> to begin to elongate axially and shrink radially. Additionally, or alternatively, interaction between the upper recovery profile <NUM> of the upper recovery sleeve <NUM> and the packing element <NUM> may cause the packing element <NUM> to begin to move axially upward and away from the lower backup assembly <NUM>. <FIG>show the packing element <NUM> to have elongated axially, shrank radially, and moved axially upward, resulting in the inner and outer backup rings <NUM>, <NUM> of the lower backup assembly <NUM> retracting at least partially from their splayed outward positions.

Upward movement of the packing element <NUM> may also cause upward movement of the lower recovery sleeve <NUM> due to interaction between the lower recovery profile <NUM> of the lower recovery sleeve <NUM> and the packing element <NUM>. As illustrated, a stop ring <NUM> on the lower recovery sleeve <NUM> may transfer an upward force, and upward movement, to the lower inner backup sleeve <NUM>. Upward movement of the lower inner backup sleeve <NUM> may be transferred through the boost housing extension <NUM>, the boost housing <NUM>, and the boost mandrel <NUM> to the slip assembly skirt <NUM> via a stop ring <NUM> on the boost mandrel <NUM>.

Upward movement of the slip assembly skirt <NUM> may cause upward movement of the upper support cone <NUM> away from the upper base cone <NUM>. Hence, the upper support cone <NUM> may move away from each upper extension ramp <NUM>. As illustrated, each upper extension ramp <NUM> may pivot from the extended position towards the retracted position under the influence of each corresponding biasing member <NUM>.

Additionally, as illustrated, upward movement of the equalization mandrel <NUM> has caused upward movement of the release mandrel <NUM>, and upward movement of the support ring <NUM> because of the engagement between the ratchet teeth <NUM> on the release mandrel <NUM> with the ratchet teeth <NUM> of the lock ring <NUM> in the support ring <NUM>. Consequently, the radial support for the one or more release lug <NUM> to be in engagement with the release housing <NUM> had been removed, and thus upward movement of the central mandrel <NUM> may cause, as illustrated, upward movement of the release sub <NUM> such that each release lug <NUM> becomes disengaged from the release housing <NUM>.

Details of the bridge plug <NUM> corresponding to the status shown in <FIG> are shown in <FIG>. The following description highlights at least some of the changes to occur in transitioning from the configuration shown in <FIG>. A further axial tensile force applied to the fishing neck <NUM> of the setting tool adaptor <NUM> is transferred, as described above, via the central mandrel <NUM> to the upper recovery sleeve <NUM>, thereby causing the packing element <NUM> to elongate axially and shrink radially. The central mandrel <NUM> and the release sub <NUM> have moved further upwards with respect to the slip assembly <NUM>.

Details of the bridge plug <NUM> corresponding to the status shown in <FIG> are shown in <FIG>. The following description highlights at least some of the changes to occur in transitioning from the configuration shown in <FIG>. A further axial tensile force applied to the fishing neck <NUM> of the setting tool adaptor <NUM> is transferred via the central mandrel <NUM> and the stop ring <NUM> on the boost mandrel <NUM> to the slip assembly skirt <NUM> and the upper support cone <NUM>. Upward movement of the upper support cone <NUM> with respect to the upper cone sleeve <NUM> ceased when at least one key <NUM> in the upper support cone <NUM> reached the end of the corresponding slot <NUM> in the upper cone sleeve <NUM>. Thereafter, further axial tensile force has in turn been transferred to the slip mandrel <NUM>.

Because the slip mandrel <NUM> is coupled to the shear sub <NUM> via the lock ring <NUM>, the shear sub <NUM> has experienced an upward force which, upon reaching a threshold value, has defeated (such as by shearing) the one or more fastener <NUM> coupling the shear sub <NUM> to the slip assembly connector <NUM>, thereby releasing the shear sub <NUM> and permitting the slip mandrel <NUM> and shear sub <NUM> to move upwards with respect to the lower cone assembly <NUM> and to the slip member(s) <NUM>. Further upward movement of the central mandrel <NUM> has resulted in the upper cone sleeve <NUM>, upper base cone <NUM>, and the slip mandrel <NUM> moving upwards with respect to the slip member(s) <NUM>. Hence, the upper base cone <NUM> has moved away from the upper gripper <NUM> of each slip member <NUM>, and the biasing members <NUM>, <NUM> were able to commence retracting the slip member(s) <NUM>.

During the transition between <FIG> and <FIG>, a lower end of the slot <NUM> in the slip mandrel <NUM> encountered the key <NUM> of the slip cage <NUM>, and further upward movement of the slip mandrel <NUM> caused the slip cage <NUM> to move upwards with respect to the lower cone assembly <NUM>. Thus, the lower gripper <NUM> of each slip member <NUM> became axially separated from the lower cone assembly <NUM>, and the biasing members <NUM>, <NUM> caused the slip member(s) <NUM> to retract. Additional upward movement of the slip mandrel <NUM> with respect to the lower cone assembly <NUM> caused the shear sub <NUM> to contact and raise the lower cone sleeve <NUM> with respect to the lower support cone <NUM>, thereby axially separating the lower base cone <NUM> from the lower support cone <NUM>. As illustrated, each lower extension ramp <NUM> has pivoted towards the retracted position under the influence of each corresponding biasing member <NUM>.

In some embodiments, the magnitude of axial separation between the lower base cone <NUM> and the lower support cone <NUM> may be governed by the interaction between the one or more key <NUM> that couples the lower support cone <NUM> with the lower cone sleeve <NUM> and the corresponding slot <NUM> in the lower cone sleeve <NUM>. When the end of the corresponding slot <NUM> in the lower cone sleeve <NUM> reaches the one or more key <NUM> in the lower support cone <NUM>, the lower support cone <NUM>, the release housing <NUM>, and the ported sub <NUM> may be carried by the one or more key <NUM> in the lower support cone <NUM>.

In some embodiments, the magnitude of axial separation between the lower base cone <NUM> and the lower support cone <NUM> may be governed by the shear sub <NUM> encountering an internal shoulder <NUM> of the lower support cone <NUM>. The lower support cone <NUM>, the release housing <NUM>, and the ported sub <NUM> may be carried by the shear sub <NUM>.

Upon the retraction of the slip member(s) <NUM>, the bridge plug <NUM> is no longer anchored to the bore in which the bridge plug <NUM> had been installed, and therefore the bridge plug <NUM> may be retrieved.

In summary, a bridge plug of the present disclosure incorporating a packer assembly of the present disclosure and a slip assembly of the present disclosure may be run into a bore, including being run through a restriction in the bore. The bridge plug may be actuated to a set configuration in which the slip assembly is anchored to a wall of the bore within a portion of the bore that is greater than the size of the restriction and a packing element of the packer assembly seals against the wall of the bore. The bridge plug may be further actuated to disengage from the wall of the portion of the bore, and to transition to a size that may fit through the restriction to enable retrieval from the bore. The bridge plug may be retrieved from the bore, including being retrieved through the restriction in the bore.

In some embodiments of the packer assembly <NUM>, the packing element <NUM> may include multiple pieces of packing material, such that the packing element <NUM> is not considered as a unitary structure. For example, the packing element <NUM> may include a plurality of individual sections of deformable material, such as individual elastomeric sections. The plurality of individual sections may be positioned adjacent to one another on the packer mandrel <NUM>. In some embodiments, the plurality of individual deformable sections may be separated by annular rings.

In some embodiments, one or more spacer ring may be disposed within and/or about the packing element <NUM>. <FIG> show an example packer assembly <NUM> in which the filler rings <NUM> have been replaced by spacer rings <NUM> disposed about packing element <NUM>. <FIG> show the packer assembly in an unset configuration, such as a deployment configuration. <FIG> show the packer assembly <NUM> of <FIG>, respectively, in a set configuration in which the packing element <NUM> has undergone axial compression resulting in a corresponding radial enlargement. In <FIG> the packing element <NUM> has deformed around the spacer rings <NUM>, thereby forming folds <NUM>.

In embodiments in which the packing element <NUM> is not considered as a unitary structure, the one or more spacer ring <NUM> may be disposed about one, some, or all of the plurality of sections of the packing element <NUM>. In some embodiments, a spacer ring <NUM> may be bonded to the packing element <NUM>. In some embodiments, a spacer ring <NUM> may not be bonded to the packing element <NUM>. A spacer ring <NUM> may be made out of a rigid material, such as steel.

In some embodiments, a spacer ring <NUM> may not undergo a substantial change in shape or size when the packer assembly <NUM> is transitioned from the running configuration to the set configuration. In some embodiments, a spacer ring <NUM> may not undergo a substantial change in shape or size when the packer assembly <NUM> is transitioned from the set configuration to a released configuration. In some embodiments, a spacer ring <NUM> may have a first maximum outer diameter before the packer assembly <NUM> is transitioned from a running configuration to the set configuration, a second maximum outer diameter after the packer assembly <NUM> is transitioned from the running configuration to the set configuration, and the second maximum outer diameter may be substantially the same as the first maximum outer diameter. In some embodiments, a spacer ring <NUM> may have a third maximum outer diameter after the packer assembly <NUM> is transitioned from the set configuration to the released configuration, and the third maximum outer diameter may be substantially the same as the first maximum outer diameter.

In some embodiments of the slip assembly <NUM>, the extension ramps <NUM>, <NUM> may transition between retracted and extended configurations by sliding laterally with respect to the corresponding base cone <NUM>, <NUM>. <FIG> show an embodiment of a slip cone assembly <NUM> that may be used in place of upper cone assembly <NUM> and/or lower cone assembly <NUM> in slip assembly <NUM>. <FIG> show the slip cone assembly <NUM> in an unset configuration; <FIG> show the slip cone assembly <NUM> in a set configuration. One or more extension ramp <NUM> may be disposed between a support cone <NUM> and a rear face <NUM> of a base cone <NUM>, and may be coupled to the base cone <NUM> using a key <NUM>. Each extension ramp <NUM> may have a sloped outer surface <NUM> and a sloped inner surface <NUM>. The sloped inner surface <NUM> may be configured to interact with a sloped outer surface <NUM> of the support cone <NUM>. As shown in <FIG>, the sloped outer surface <NUM> of each support cone <NUM> may include a concave portion at an interface with the sloped inner surface <NUM> of each extension ramp <NUM>.

When transitioning from the running configuration to the set configuration, at least one of the support cone <NUM> and the base cone <NUM> may be moved toward the other of the base cone <NUM> and the support cone <NUM>. The sloped outer surface <NUM> of the support cone <NUM> interacts with the sloped inner surface <NUM> of each extension ramp <NUM>, thereby causing each extension ramp <NUM> to move from a retracted position to an extended position. For each extension ramp <NUM>, the key <NUM> may travel within a keyway <NUM>, and the interaction between the key <NUM> and the keyway <NUM> may limit the maximum extent of travel of the extension ramp <NUM>. Additionally, or alternatively, the maximum extent of travel of each extension ramp <NUM> may be limited by an interaction between a shoulder <NUM> on the support cone <NUM> and a corresponding shoulder <NUM> on each extension ramp <NUM>. When an extension ramp <NUM> is in the extended position, the sloped outer surface <NUM> may be substantially aligned with a sloped outer surface <NUM> of the base cone <NUM>. A sloped inner surface <NUM>, <NUM> of a gripper <NUM>, <NUM> of a slip member <NUM> may slide along the sloped outer surface <NUM> of the base cone <NUM> and the sloped outer surface <NUM> of the extension ramp <NUM>.

In some embodiments, as shown in <FIG>, the base cone <NUM> may be omitted from slip cone assembly <NUM>. <FIG> show a slip assembly <NUM> incorporating two slip cone assemblies <NUM> in an unset configuration; <FIG> show the slip assembly <NUM> in a set configuration. Slip cone assembly <NUM> may be utilized in place of slip cone assembly <NUM> or upper cone assembly <NUM> or lower cone assembly <NUM> in slip assembly <NUM>. In each slip cone assembly <NUM>, each extension ramp <NUM> may have a sloped outer surface <NUM> coupled to a sloped inner surface <NUM>, <NUM> of a gripper <NUM>, <NUM> of a slip member <NUM>. Each extension ramp <NUM> may have a tang <NUM> that is configured to slide within a corresponding slot <NUM> of each gripper <NUM>, <NUM> of each slip member <NUM>. The tang <NUM> may cooperate with the slot <NUM> such that relative axial movement between each extension ramp <NUM> and each slip member <NUM> may result in radial movement of each slip member <NUM> between extended and retracted positions. The sloped outer surface <NUM> of each support cone <NUM> may include a concave portion at an interface with the sloped inner surface <NUM> of each extension ramp <NUM>.

When transitioning from the running configuration to the set configuration, each support cone <NUM> of each slip cone assembly <NUM> may be moved towards the slip cage <NUM> of the slip assembly <NUM>. Movement of each support cone <NUM> towards the slip cage <NUM> may cause movement of each extension ramp <NUM> towards the slip cage <NUM>. The sloped inner surface <NUM>, <NUM> of each gripper <NUM>, <NUM> of each slip member <NUM> may slide along the sloped outer surface <NUM> of each extension ramp <NUM> when each extension ramp <NUM> is being moved toward the slip cage <NUM>. Thus, each slip member <NUM> may move radially towards an extended position. In some embodiments, each extension ramp <NUM> may contact the slip cage <NUM>. Continued movement of each support cone <NUM> towards the slip cage <NUM> may cause the sloped outer surface <NUM> of each support cone <NUM> to interact with the sloped inner surface <NUM> of each extension ramp <NUM>, thereby causing each extension ramp <NUM> to move from a radially retracted position to a radially extended position. Such movement of each extension ramp <NUM> may cause each slip member <NUM> to move further towards the extended position. Thus, each slip member <NUM> may be moved from the retracted position to the extended by each extension ramp <NUM> first moving predominately in an axial direction, and then moving predominately in a radial direction.

In some embodiments, a biasing member <NUM>, such as a spring or a mass of resilient deformable material, such as an elastomer, may be located between each support cone <NUM> and each extension ramp <NUM>. In some embodiments, the biasing member <NUM> may be located between corresponding shoulders <NUM>, <NUM> on each support cone <NUM> and on each extension ramp <NUM>, respectively. The biasing member <NUM> may urge each extension ramp <NUM> toward the retracted position.

In some embodiments, as shown in <FIG>, the slip cage <NUM> may include one or more retainer <NUM> that is not radially movable with respect to the slip cage body <NUM>. In some embodiments, as shown in <FIG>, a garter spring <NUM> may be located around the slip members <NUM>. The garter spring <NUM> may be located within a recess <NUM> of each slip member <NUM>. The garter spring <NUM> may bias the slip members <NUM> toward the retracted position. The garter spring <NUM> may be used in addition to or instead of the biasing member <NUM> located between each slip member <NUM> and each corresponding retainer <NUM>.

In some embodiments, the bridge plug <NUM> may be configured to be transitioned from the set configuration to the released configuration, but the method of use may not involve releasing the bridge plug <NUM>. In such embodiments, the steps that would be performed to achieve release of the bridge plug <NUM> may be omitted.

In some embodiments, the bridge plug <NUM> may not be configured to be transitioned from the set configuration to the released configuration. In such embodiments, the components that facilitate the release of the bridge plug <NUM> may be modified or omitted in order to avoid an inadvertent release of the bridge plug <NUM>.

The various embodiments of the packer assembly <NUM>, <NUM> of the present disclosure may be utilized with other tools and systems apart from the bridge plug <NUM>. For example, the packer assembly <NUM>, <NUM> may be used as a sealing system for a downhole/pipeline packer, a liner hanger, a straddle assembly, a whipstock, a pressure test tool, a production test tool (such as a drill stem test tool), a storm packer tool, a casing hanger, or any other downhole or pipeline service tool.

In some embodiments, the various embodiments of the packer assembly <NUM>, <NUM> of the present disclosure may be configured to be transitioned from the set configuration to the released configuration, but the method of use may not involve releasing the packer assembly <NUM>, <NUM>. In such embodiments, the steps that would be performed to achieve release of the packer assembly <NUM>, <NUM> may be omitted.

In some embodiments, the packer assembly <NUM>, <NUM> may not be configured to be transitioned from the set configuration to the released configuration. In such embodiments, the components that facilitate the release of the packer assembly <NUM>, <NUM> may be modified or omitted in order to avoid an inadvertent release of the packer assembly <NUM>, <NUM>.

The various embodiments of the slip assembly <NUM>, <NUM> of the present disclosure may be utilized with other tools and systems apart from the bridge plug <NUM>. For example, the slip assembly <NUM>, <NUM> may be used as an anchoring system for a downhole/pipeline packer, a liner hanger, a straddle assembly, a whipstock, a pressure test tool, a production test tool (such as a drill stem test tool), a storm packer tool, a casing hanger, or any other downhole or pipeline service tool.

In some embodiments, the various embodiments of the slip assembly <NUM>, <NUM> of the present disclosure may be configured to be transitioned from the set configuration to the released configuration, but the method of use may not involve releasing the slip assembly <NUM>, <NUM>. In such embodiments, the steps that would be performed to achieve release of the slip assembly <NUM>, <NUM> may be omitted.

In some embodiments, the slip assembly <NUM>, <NUM> may not be configured to be transitioned from the set configuration to the released configuration. In such embodiments, the components that facilitate the release of the slip assembly <NUM>, <NUM> may be modified or omitted in order to avoid an inadvertent release of the slip assembly <NUM>, <NUM>.

In some embodiments of the present disclosure, a slip assembly includes a first support cone configured to move a first extension ramp between retracted and extended positions. The first extension ramp is biased towards the retracted position by a first biasing member. The slip assembly further includes a second support cone configured to move a second extension ramp between retracted and extended positions. The second extension ramp is biased towards the retracted position by a second biasing member. The slip assembly further includes a slip member disposed between the first extension ramp and the second extension ramp. The slip member is configured to slide between retracted and extended positions along an outer surface of the first extension ramp and along an outer surface of the second extension ramp.

In some embodiments of the present disclosure, a slip assembly includes a slip cage body having a radial opening. A retainer disposed in the radial opening is movable between a retracted position and an extended position. A slip member has a shank between first and second gripping elements, and the shank is disposed between the slip cage body and the retainer. A first biasing member is disposed between the retainer and the slip cage body, and a second biasing member is disposed between the shank and the retainer.

In some embodiments of the present disclosure, a slip assembly includes a slip cage body having a radial opening. A retainer disposed in the radial opening is movable between a retracted position and an extended position. A slip member has a shank between first and second gripping elements, and the shank is disposed between the slip cage body and the retainer. A first biasing member is disposed between the retainer and the slip cage body, and a second biasing member is disposed between the shank and the retainer. The slip member is movable between a retracted position and an extended position. When the slip member moves towards the extended position, the retainer moves towards the extended position.

In some embodiments of the present disclosure, a slip assembly includes a slip cage body having a radial opening. A retainer disposed in the radial opening is movable between a retracted position and an extended position. A slip member has a shank between first and second gripping elements, and the shank is disposed between the slip cage body and the retainer. A first biasing member is disposed between the retainer and the slip cage body, and a second biasing member is disposed between the shank and the retainer. A first cone assembly is configured to bear against the first gripping element, and a second cone assembly is configured to bear against the second gripping element. The first and second cone assemblies are configured to move the slip member from a retracted position to an extended position. When the slip member moves towards the extended position, the retainer moves towards the extended position.

Claim 1:
A slip assembly comprising:
a slip mandrel (<NUM>);
a first cone assembly (<NUM>, <NUM>) coupled to the slip mandrel (<NUM>), the first cone assembly (<NUM>) comprising:
a first base cone (<NUM>, <NUM>), and
a first extension ramp (<NUM>, <NUM>) coupled to the first base cone (<NUM>, <NUM>), the first extension ramp (<NUM>, <NUM>):
movable between a radially retracted position and a radially extended position, and
biased toward the radially retracted position by a first biasing member (<NUM>, <NUM>); and
a slip member (<NUM>) disposed adjacent the first base cone (<NUM>, <NUM>), the slip member (<NUM>) configured to slide between retracted and extended positions along an outer surface of the first base cone (<NUM>, <NUM>) and along an outer surface of the first extension ramp (<NUM>, <NUM>), when the extension ramp is in the extended position.