Abstract: A drilling assembly includes a drill string configured to be disposed within a wellbore. The drilling assembly also includes a sub fluidically coupled to the drill string. The sub includes a mandrel fixed to the drill string and defines an external helically undulated surface and a bore configured to flow drilling fluid received from the drill string. The sub includes a sleeve rotationally coupled to and disposed outside the mandrel. The sleeve has an internal helically undulated surface corresponding with the external helically undulated surface of the mandrel to form, with the mandrel, a progressive cavity. The progressive cavity receives fluid from the bore of the mandrel to rotate the sleeve as the drilling fluid flows along the cavity. The sub also includes a valve configured to regulate a flow of the drilling fluid along the bore to direct fluid toward or away from the progressive cavity.

Abstract: Forming an anchored plug in a wellbore utilizing grain-like solids to transfer an axial force to a radial force to dissipate the axial force within an effective screening length.

Abstract: An assembly is used for chemical injection through a wellhead to a capillary line in a well. A capillary hanger installs in the wellhead to support the capillary line. A no-return valve of the capillary hanger prevents fluid communication uphole from the supported capillary line. An injection module mounts above a gate valve on the wellhead and includes a movable mandrel disposed therein. Hydraulic pressure applied to a piston chamber in the module extends the mandrel through the open gate valve so that a distal end of the mandrel can open the no-return valve. At this point, chemical injection introduced into the module can communicate through a flow bore of the extended mandrel, through the open non-return valve, and on through the supported capillary line in the well.

Abstract: A circular cutting torch includes a thermal igniter assembly; a compressed grain magazine, the compressed grain magazine coupled to the thermal igniter; and a severing head assembly. The severing head assembly includes a one-piece severing head and a progressive compression deflector. The one-piece severing head and progressive compression deflector define a radial gap therebetween used to expel a jet of molten combustible material for cutting a downhole tubular member such as pipe or casing.

Abstract: Apparatus and method for securing and sealing a tubular portion to another tubular to provide a liner hanger in oil and gas wells. At the top of the liner string, a sleeve is arranged on the liner to create a chamber therebetween. A port provides fluid access through the liner to the chamber. When fluid is introduced into the chamber the sleeve is morphed to secure it to the cemented casing. A lower fluid pressure is required to morph the sleeve than if the liner itself was to be morphed. Embodiments are provided for securing and sealing arrangements to increase the metal to metal seal and the load capability between the liner string and casing.

Abstract: A hanger running tool configured to set a hanger assembly within a wellhead includes a rotatable tool configured to couple to the hanger assembly via a first threaded interface having a first orientation. The hanger running tool also includes an outer sleeve coupled to the rotatable tool, and the outer sleeve includes one or more slots configured to engage a drive ring coupled to the hanger assembly via a second threaded interface having a second orientation opposite the first orientation. Rotation of the rotatable tool in a first direction is configured to loosen the rotatable tool from the hanger assembly while causing the one or more slots of the outer sleeve to drive the drive ring in the first direction, thereby tightening the drive ring about the hanger assembly and causing the drive ring to drive a lock ring radially-outwardly to engage a corresponding recess of the wellhead.

Abstract: An inwardly biased tubing hanger is provided that allows for continued turns in the same direction to both lock the tubing hanger in place within the well as well as release the running tool from the tubing hanger. An energizing sleeve and running tool each having left hand threads is provided where a torque ring between the energizing sleeve and running tool allows the running tool to be turn in the right hand direction until sufficient torque is provided to the torque sleeve to release the running tool from the energizing sleeve. With the running tool attached to the energizing sleeve the energizing sleeve provides sufficient force, provided the torque limit of the torque sleeve is not been reached, to drive the inwardly biased torque ring radially outward.

Abstract: A plug assembly includes an expandable assembly and a locking ring. The expandable assembly is adapted to be deformed radially over the locking ring. The plug assembly is used with an untethered object, which is adapted to contact an inside surface of the plug assembly and, using well fluid pressure, to apply forces to the plug assembly. The forces cause further radial deformation of the expandable assembly, and penetration of an internal surface of the tubing string at least at one point with a gripping portion of the expandable assembly.

Abstract: The invention relates to a maintenance device (1) for determining the position of a blockage point (2) of a tubular member (3), characterized in that it includes a fiber-optic cable (40) and a plurality of holding guides (20), each holding guide (20) being attached to the fiber-optic cable (40) and including a means (21) for attaching to the tubular member (3). The invention also relates to a method and a system for determining the position of a blockage point of a tubular member.

Abstract: A system that includes a drillstring with a bottomhole assembly (BHA). The system also includes at least one stabilizer or reamer integrated with the BHA, wherein each of the at least one stabilizer or reamer includes a position adjustment assembly. The system also includes a processing unit that provides control signals to each position adjustment assembly, wherein the control signals are based on a cost function.

Abstract: A tie-back string and a method of coupling the tie-back string to a casing is disclosed. The tie-back string is disposed within the casing. The tie-back string includes an anchor and an actuator section. The actuator section including a sleeve that forms a first chamber and a setting piston that forms a second chamber. A pressure differential is created between the first chamber and the second chamber to move the setting piston to engage the anchor of the tie-back string.

Abstract: There is provided a rotating split tubing hanger, including: a mandrel having a bore therein and a mandrel exterior surface, the mandrel attachable to a tubing string; a housing sleeve mountable on the exterior surface of the mandrel, the mandrel being rotatable relative to the housing sleeve, and the housing sleeve comprising a housing sleeve exterior surface; and an outer sleeve removably mountable on the housing sleeve exterior surface, the outer sleeve comprising an outer sleeve exterior support surface engageable with a tubing head.

Abstract: An expandable liner hanger includes an anchoring element having multiple circumferential ridges that include flow relief grooves which prevent buildup of hydrostatic pressure between the liner hanger and well casing during expansion of the liner hanger. Upon liner hanger expansion the ridges come in high interference with wellbore casing and couple the liner hanger to the wellbore casing. According to another embodiment of the invention, the ridges are formed by a spiral ridge extending along an outer periphery of the hanger thus providing a pressure relief passage for the fluid.

Abstract: Blowout preventers having bodies with internal choke and kill line pass-through conduits are provided. In one embodiment, a blowout preventer body (42) includes a drill-through bore (44) extending through the blowout preventer body and a ram cavity (58) transverse to the drill-through bore. The blowout preventer body can also include choke and kill line conduits (136, 138) extending through the blowout preventer body, as well as choke and kill line access branch conduits (148, 150) extending between the choke and kill line conduits and the drill-through bore. Additional systems, devices, and methods are also disclosed.

Abstract: Sealing element system for a downhole bridge plug assembly may include a packer mandrel. At least one sealing element may be carried by the packer mandrel. A first completion ring may be carried by the packer mandrel on a first side of the at least one sealing element. The first completion ring may have a first beveled outer completion ring surface. A second completion ring may be carried by the packer mandrel on a second side of the at least one sealing element. The second completion ring may have a second beveled outer completion ring surface. A first backup ring support may be carried by the packer mandrel proximate the first completion ring. A second backup ring support may be carried by the packer mandrel proximate the second completion ring. A first backup ring may be carried by the first backup ring support. The first backup ring may include a circumferentially-expandable first backup ring body. A first ring sleeve may extend from the first backup ring body.

Abstract: A bottom hole assembly (BHA) comprising: a first component of a wet latch assembly, the first component configured for coupling, when extended into the interior flow bore of the BHA, with a second component of the wet latch assembly to provide an assembled wet latch assembly, such that an electrical connection can be made between the first component and the second component; and a formation tester operable for performing a formation test, the formation tester electrically connected with the first component of the wet latch assembly, such that power and/or telemetry can be provided to the formation tester via the assembled wet latch assembly during the formation test.

Abstract: A wellbore isolation device, comprising: a mandrel 24 having a cylindrical body, a sealing element 38 disposed about the mandrel 24 and radially expandable from a first run-in diameter to sealing engagement with the an inner surface 50 of the wellbore 6; a metal backup ring 60 disposed on the mandrel 24 contacting one side of the sealing element system 38 with an initial height H and radially expandable and axially deformable to abut the inner surface 50 of the wellbore 6; wherein the metal backup ring 60 is a concave cross-section about the mandrel 24 with an uphole leg and a downhole leg; and wherein an applied compressive force expands the sealing element system 38 into sealing engagement with the wellbore 6 and the metal backup ring 60 radially expands while axially deforming to abut the inner surface 50 of the wellbore 6 with no contact pressure.

Abstract: A method for disposing a completion assembly within a wellbore in a single trip. The completion assembly includes a mechanical formation isolation valve in an open position, a production sealing element, and a production sealing element setting tool. An acid wash is performed using the completion assembly within the wellbore. After performing the acid wash, the production sealing element is activated with the production sealing element setting tool, fluidically sealing a wellbore upper section uphole of the completion assembly from a wellbore lower section downhole of the completion assembly. The production sealing element setting tool is decoupled from the production sealing element. The mechanical formation isolation valve is maintained in the open position. The production sealing element setting tool is pulled out of the wellbore.

Abstract: A rotating control device includes a bowl housing with an inner aperture to receive a seal and bearing assembly. A plurality of hydraulically-actuated fail-last-position latching assemblies are disposed about an outer surface of the bowl housing to controllably extend a plurality of piston-driven dogs radially into a groove of the seal and bearing assembly. The seal and bearing assembly includes a housing, a mandrel disposed within an inner aperture of the housing, a first interference-fit sealing element attached to a bottom distal end of the mandrel, a plurality of tapered-thrust bearings indirectly mounted to the housing, a preload spacer disposed between top and bottom tapered-thrust bearings, a plurality of jam nuts to adjust a preload of the tapered-thrust bearings and a lower seal carrier attached to the seal and bearing housing comprising a plurality of dynamic sealing elements that contact the mandrel.

Abstract: A system is disclosed as including an enclosed space within a seal for sealing an area between a hanger and a housing of a wellhead. The enclosed space traverses a first section of the seal, a middle section of the seal, and an opening at a second section of the seal. A port is provided as accessible from the housing. A tool positions the seal within the hanger and the housing so that the port is able to access the enclosed space from the housing to the hanger. A pressure applicator applies fluid into the port at a pressure, which is monitored to determine integrity of the seal. In a monitoring mode, a pressure is monitored at the port. A change in the pressure from an ambient pressure at the port may indicate an on-going issue with the seal. Methods applied to the system are also disclosed.

Abstract: A system for subterranean deployment in a wellbore includes an expandable tubular having an outer surface supporting at least one anchor slip and an inner surface including a running tool engagement element, and a running tool for deploying the expandable tubular into the wellbore. The running tool includes an inner surface portion defining a passage and an outer surface portion supporting a forcing cone for expanding at least a portion of the expandable tubular, and a tubular support system selectively engaging with the running tool engagement element.

Abstract: A downhole tool includes a tool body and an anchoring device integrated with the tool body. The anchoring device includes a contact pad that is at least partially external to the tool body, the contact pad having multiple stages with different thicknesses. The anchoring tool also includes a first linear actuator and a second linear actuator. The first linear actuator is configured to move the contact pad axially with respect to the tool body to align one of the multiple stages with the second linear actuator. The second linear actuator is configured to apply a radial force to the contact pad.

Abstract: An energizing ring for setting a downhole sealing element includes a passage extending through a width of the energizing ring and a wing extending radially outward from a body of the energizing ring, the wing includes a sealing arm coupled to the body at a joint and a slot arranged between at least a portion of the sealing arm and the body, wherein the sealing arm is configured to pivot relative to the joint in response to a fluid pressure within the cavity.

Abstract: The present disclosure relates to a vise arrangement for a directional drilling machine. The vise arrangement can include a translatable and pivotal vise. The vise arrangement can also include up-hole and down-hole rod guides/supports. The vise arrangement can further include a lubrication dispenser.

Abstract: A packer includes a sealing element positioned at least partially around a tubular, the sealing element having an axial end, a gage ring positioned at least partially around the tubular and adjacent to the axial end of the sealing element, and a plurality of petals pivotally coupled to the gage ring, extending at least partially axially therefrom toward the sealing element, and positioned radially outwards of the axial end of the sealing element. The gage ring is movable axially along the tubular, towards the sealing element, such that the gage ring applies an axial force to the sealing element to expand the sealing element radially outwards, and the plurality of petals are configured to pivot radially outwards when the sealing element radially expands.

Abstract: An assembly adapted to be disposed within an oil or gas wellbore and including first and second completion joints, each including a base pipe, a shunt tube disposed along the base pipe, and a tubular outer shroud disposed about respective portions of the shunt tube and the base pipe; a jumper tube coupling the shunt tube of the first completion joint to the shunt tube of the second completion joint; and a tubular sliding shroud disposed about at least one of the first and second completion joints and adapted to slide longitudinally to a run-in position, in which the tubular sliding shroud is disposed about the jumper tube and respective portions of the first and second completion joints, thereby covering the jumper tube. A method and apparatus are also provided.

Abstract: A system for controlling a downhole component within a borehole, the system including a transfer assembly coupled between a rotatable component and the downhole component, the transfer assembly including a swash plate assembly configured to control the downhole component and a member configured to engage the swash plate assembly. The member is configured to move radially based upon a rotational speed of the rotatable component to selectively engage the swash plate assembly.

Abstract: A downhole tool, configured to receive a milling tool or other forcing tool, includes: a tubular mandrel; an adapter housing coupled to the mandrel; a guide sleeve disposed within the adapter housing; a movable sleeve configured for sliding movement within the guide sleeve; and a retainer positioned uphole of the movable sleeve. The retainer includes an upper annular portion, a lower annular portion, an annular void between the upper and lower annular portions, and a bridge portion extending between the upper and lower annular portions. The upper annular portion is initially fixed to the guide sleeve. The lower annular portion is configured such that downward movement of the lower annular portion causes the movable sleeve to move downward within the guide sleeve. The bridge portion comprises a through-passage and a thin walled segment adjacent to the void. Milling or otherwise disconnecting the bridge portion permits the lower annular portion to move the moveable sleeve.

Abstract: A sealing device for a well plug includes a mandrel device, a sealing element, a first supporting device provided on a first side of the sealing element and a second supporting device provided on a second side of the sealing element. Each supporting device includes proximal supporting elements provided proximal to the sealing element and distal supporting elements, where first ends of the respective proximal and distal supporting elements are pivotably connected to each other. The second ends of the proximal supporting elements are pivotably connected to a connector of a proximal supporting ring. The sealing device is brought from a run state to a first set state by relative axial movement of the distal supporting rings towards each other and relative axial movement of the proximal supporting rings towards each other.

Abstract: A downhole wellbore system is provided, comprising one or more downhole sleeves run on a liner; and an intervention tool deployable into the liner. The intervention tool is reciprocateable within the line and one or more downhole sleeves between any one or more positions selected from the group consisting of: downhole sleeve opening position, downhole sleeve closing position, pull uphole position, push downhole position, and setting in a blank section of the liner position. A method is further provided for manipulating an intervention tool in a liner comprising one or more downhole sleeves. The method comprises the steps of deploying an intervention tool into the liner and reciprocating the intervention tool between one or more positions selected from the group consisting of: downhole sleeve opening position, downhole sleeve closing position, pull uphole position, push downhole position, and setting in a blank section of the liner position.

Abstract: A frac plug that is energized by a ball member, the frac plug comprising an upper mandrel having a tapered outer surface, a seal member coupled to the upper mandrel, and a lower mandrel coupled to the upper mandrel. A button ring having one or more buttons is disposed about the upper mandrel. The lower mandrel is movable relative to the upper mandrel to move the button ring along the tapered outer surface and force the buttons into gripping contact with a surrounding wellbore. The seal member is movable into sealing contact with the surrounding wellbore by the ball member.

Abstract: A frac plug is provided. The frac plug includes a plug body, a sealing element, and a slip. The plug body includes a first sub and a second sub. The first sub includes a first composite material outer sleeve, and a first metal inner core engaged with and structurally supporting the first composite material outer sleeve. The second sub includes a second composite material outer sleeve, and a second metal inner core engaged with and structurally supporting the second composite material outer sleeve. The sealing element is circumferentially disposed about the first sub and, when actuated, seals an annulus between the frac plug and a tubular section. The slip is disposed between the first sub and the second sub and, when actuated, engages the tubular section.

Abstract: A system that includes a wellhead. The wellhead defines a bore. A hanger system is positioned within the wellhead. The hanger system includes a piston angled relative to a longitudinal axis of the bore. A first spring biases the piston in a first direction. The piston contacts a slip segment to couple the slip segment to a casing string.

Abstract: A method for completing a well includes extending coiled tubing into the well through a wellhead assembly, the coiled tubing having a lower end within the well and an upper end outside of the well. A tool is releasably attached to a central portion of the coiled tubing between the lower and upper ends. The tool has a tool body has an inner diameter surface sized to circumscribe the coiled tubing. A gripping feature is located on the inner diameter surface for limiting relative axial movement between the tool and the coiled tubing when the inner diameter of the tool circumscribes the coiled tubing. A tool feature extends from the tool body and is shaped to engage a well member. The tool is lowered into the well with the coiled tubing and the tool feature engages the well member. The tool is removed from the well with the coiled tubing.

Abstract: A well tubular is expanded using an expandable segmented cone (301-303) which is at a large diameter bottom or gauge section of the cone (301-303) provided with a robust sealing assembly (300A-C) comprising a sealing ring or sealing lips that engage(s) an expanded section of the tubular (307).

Abstract: A liner assembly tool includes a base tubular that includes a bore therethrough; a wellbore liner that includes a liner top and is coupled to the base tubular; a pack-off element radially positioned between the base tubular and the wellbore liner to ride on the base tubular; and a wedge positioned to ride on the base tubular and expand the pack-off element to at least partially seal the liner top to a wellbore wall based on a particular fluid pressure supplied through the bore.

Abstract: A stackable support system and method are disclosed to increase the final contact area of an expanding lock component by stacking one ring on top of another such that one ring acts as an actuator for the one beneath it. As a body lands inside a receptacle, e.g. a narrow cylinder lands inside a larger cylinder, the components or rings expand in a domino effect, resulting in a greater contact between the body and receptacle than would occur if there was only one component or ring. The stackable support system includes a number of expandable lock rings which stack on top of each other. These rings, when expanded, steadily increase in diameter, resulting in an overall larger surface on the bottom of the support system than could have been achieved with one ring.

Abstract: A valve that allows control of each of one or more flow paths using one actuator is presented. Rotary motion of a motor is transformed into linear motion using a roller screw mechanism. The travel of the roller screw nut is predefined between front and back hard stops that prevent the roller screw from rotating when the stops are reached. A poppet is attached to the nut using a flexible connection. The nut drives a sleeve with inclined surfaces that moves relative to a locking flexure. When the sleeve is driven, it deforms flanges of the locking flexure causing a cantilever end finger of the flexure to move radially and prevent the poppet from being pushed back. If the sleeve is moved farther, a groove on the sleeve engages notches on the fingers creating a detent that prevents the spring to push the sleeve back.

Abstract: An apparatus for use in forming a plug during hydraulic fracturing of a subterranean soil formation comprising a top tubular retaining body extending between top and bottom ends and having a frustoconical outer surface extending from the bottom end thereof. The apparatus further includes a plurality of slip arms located around the outer surface of the retaining body, each slip arm extending between top and bottom ends and having an inner surface extending from the top end corresponding to the outer surface of the retaining body and an exterior surface adapted to frictionally engage a wellbore; and a seal element located around the outer surface of the retaining body above the plurality of slip arms adapted to be displaced towards the top end of the retaining body by the plurality of slip arms so as to seal an annulus between the retaining body and the wellbore.

Abstract: An annular sealing assembly and method are disclosed. The assembly includes a mandrel and an expandable element disposed around the mandrel which expands to seal against the inner diameter of a tubing or casing string. The expandable element seals the mandrel from the annulus between the mandrel and the tubing string. The assembly includes at least one back¬up element having a plurality of pivoting blades circumferentially secured in a ring around the mandrel. The back-up element is capable of radially expanding and contracting upon longitudinal movement along, and engagement with, a generally ring-shaped ramp. A guide ring guides the back-up element along the guide ramp. The method is directed to expanding the expandable element to seal the annulus and the back-up element so the blades come in contact with the inner diameter of the tubing string preventing the expandable element from extruding outward into the annulus beyond the back-up element.

Abstract: A downhole plug having a plug body which includes (i) a base cylinder with a first outward facing locking surface and a central bore formed there through, (ii) a single set of circumferentially spaced slip ramps formed on the base cylinder, and (iii) slip guides positioned between the slip ramps, the slip guides having a second inward facing locking surface. The plug includes a single set of slips which a plurality of slip wedges with each slip wedge engaging a slip ramp. A slip compression cap is configured to urge the slip wedges along the slip ramps and the slip compression cap includes a locking ring having a third outward facing locking surface. A compression shoulder is configured to move a ratchet ring into contact with the first locking surface on the base cylinder and the ratchet ring includes a fourth inward facing locking surface.

Abstract: A method of hanging an inner tubular string from an outer tubular string cemented in a wellbore includes running the inner tubular string and a deployment assembly into the wellbore using a deployment string, wherein a running tool of the deployment assembly longitudinally and torsionally fastens the liner string to the deployment string; plugging a bore of the deployment assembly; hanging the inner tubular string from the outer tubular string by pressurizing the plugged bore; and after hanging the inner tubular string, sending a command signal to the running tool, thereby unlocking or releasing the running tool.

Abstract: A frac plug is provided. The frac plug may include a first sub, a second sub, a slip, a sealing element, a lock ring, a back-up ring, and a compression ring. The first sub may be threadably engaged with the lock ring. The lock ring may be threadably engaged with the second sub. The slip and the back-up ring may be positioned between the first sub and the second sub, and circumferentially disposed about a tapered outer surface of the first sub. The slip and the back-up ring may include a tapered inner surface. The slip may also include a left-hand thread profile defined by the outer surface. The sealing element and compression ring may be circumferentially disposed about the first sub, and the compression ring may be threadably engaged with the first sub.

Abstract: A bridge plug for deployment in a well defined by casing has a stackable tubular body having a front portion, a middle portion, a back portion, and an internal bore extending therethrough with the front portion having a first opening in fluid communication with the internal bore and the back portion having a second opening in fluid communication with the internal bore. The stackable tubular body has an outer configuration shaped to receive another adjacent bridge plug when the adjacent bridge plug is stacked within the well. The middle portion includes an expandable component that can frictionally engage the casing to hold the bridge plug in a fixed position within the well. The expandable component can be destroyed, at least partially, to facilitate movement of the bridge plug within the well while maintaining fluid communication between the first opening and the second opening.

Abstract: A technique includes deploying an untethered object through a passageway of a string in a well to cause the untethered object to travel along the passageway. The technique includes operating the untethered object as the object travels in the passageway to expand a metal sealing device of the untethered object to cause the object to become caught at a downhole location.

Abstract: A system includes a hanger running tool that has a tool body configured to couple to a hanger via a first set of threads, a first sleeve coupled to configured to couple to the tool body via a second set of threads, where the first set of threads and the second set of threads are oriented in opposite directions, such that the first sleeve rotates in a first circumferential direction when the tool body rotates in a second circumferential direction, opposite the first circumferential direction, and a second sleeve coupled to the first sleeve, wherein the second sleeve is configured to engage a push ring of the hanger to drive a lock ring of the hanger into a recess of a casing spool.

Abstract: A downhole tool includes an upper wedge member and a lower wedge member. The upper and lower wedge members each have a circumferential width that decreases proceeding from an outer axial end thereof to an inner axial end thereof. As the downhole tool actuates from a first state to a second state, the upper and lower wedge members move axially with respect to a central longitudinal axis through the downhole tool, the upper and lower wedge members move radially-outward with respect to the central longitudinal axis, and the upper and lower wedge members remain coupled to one another as the upper and lower wedge members move.

Abstract: A centralizer assembly and method for manufacturing a centralizer assembly. The centralizer assembly includes a mandrel including a first raised region having a first diameter, and a turned-down region having a second diameter, the second diameter being smaller than the first diameter. The centralizer assembly also includes a first stop segment extending at least partially around the mandrel in the turned-down region, and a centralizer disposed at least partially in the turned-down region. The first stop segment is received between axial extents of the centralizer, to limit a range of motion of the centralizer relative to the mandrel.

Abstract: A system and method for locking together a running tool and a tubular member to rotate the tubular member. The system includes a tubular member and a running tool adapted to engage in a mechanical connection such that the running tool and the tubular member are arranged concentrically and moveable longitudinally together. The system includes a locking assembly adapted to lock the tubular member and the running tool together once the tubular member and the running tool are engaged in the mechanical connection, so that torque applied to the running tool is applied to the tubular member through the locking assembly to rotate the running tool and the tubular member synchronously. The locking assembly is adapted to unlock the tubular member and the running tool when the tubular member is landed on a shoulder of an outer tubular member so that the mechanical connection can then be disengaged.

Abstract: A wellhead housing has a bore with a landing shoulder aid an annular retaining groove spaced above the landing shoulder. A casing hanger connects to a string of easing and lands on the landing shoulder. A seal assembly between the hanger and an interior side wall of the wellhead housing below the retaining groove has an energizing ring that moves axially downward relative to the seal member to a set position that causes the seal member to sealingly engage the hanger and the interior side wall. A lockdown member has an outer lower end portion that bears against an upper end of the energizing ring and an inner lower end portion that hears against an upper end of the hanger. A lockdown ring mounted to the lockdown member engages the retaining groove to prevent upward movement of the lockdown member.