Abstract:
A tieback connector connects a tieback conduit from an offshore platform to a subsea wellhead assembly. The tieback connector has a mandrel that is connected to a string of tieback conduit and a sleeve and load ring that are carried by the mandrel. The load ring is radially expansible and has a conical portion with internal threads. The load ring has an external grooved profile that engages an internal grooved profile in the subsea assembly. The mandrel is rotatable relative to the sleeve while in its lower position, causing the load ring to further expand outward into engagement with the internal profile. A locking member is carried below the load ring on an exterior cam surface of the mandrel. The cam surface moves the locking member outward when the mandrel moves downward into engagement with an internal profile in the subsea assembly.
Abstract:
A tieback connector connects a tieback conduit from an offshore platform to a subsea wellhead assembly. The tieback connector has a mandrel that is connected to a string of tieback conduit and a sleeve and load ring that are carried by the mandrel. The load ring is radially expansible and has a conical portion with internal threads. The load ring has an external grooved profile that engages an internal grooved profile in the subsea assembly. The mandrel is rotatable relative to the sleeve while in its lower position, causing the load ring to further expand outward into engagement with the internal profile. A locking member is carried below the load ring on an exterior cam surface of the mandrel. The cam surface moves the locking member outward when the mandrel moves downward into engagement with an internal profile in the subsea assembly.
Abstract:
A self-inserting seal assembly that sets a seal at a well component to allow for pressure testing of the well component. The seal assembly can be landed on a well component with an ROV. A seal is located on the lower portion of a lower body in the assembly. A set of outer dogs lock with a grooved mating profile formed on the well component to lock the outer housing to provide a reaction point for setting the seal, which may require several thousand pounds of force. A set of inner dogs lock with a grooved mating profile formed on the inner diameter of the outer housing. This locks the lower body to the outer housing to ensure the seal remains set in place. After the well component is pressure tested, the seal assembly can be unlocked and retrieved from the well via an ROV.
Abstract:
A connector for tying back a riser from a subsea wellhead to a platform, wherein the wellhead has an internal wellhead housing with external grooves thereon. The connector having a plurality of dog members carried within a cavity which engage the external grooves. The dog members are actuated by axial movement of a piston linked to a cam ring. The connector has a plurality of transfer members located within the cavity to support the dog members and transfer upward loading to the wellhead housing during tension on one side due to bending. Further, the connector has a release ring which forces the dog members out of engagement with the external grooves when the connector is released.
Abstract:
A connector for tying back a riser from a subsea wellhead to a platform, wherein the wellhead has an internal wellhead housing with external grooves thereon. The connector having a plurality of dog members carried within a cavity which engage the external grooves. The dog members are actuated by axial movement of a piston linked to a cam ring. The connector has a plurality of transfer members located within the cavity to support the dog members and transfer upward loading to the wellhead housing during tension on one side due to bending. Further, the connector has a release ring which forces the dog members out of engagement with the external grooves when the connector is released.
Abstract:
A seal assembly includes a tubular member having a longitudinal axis and a tubular member seal profile. A metal seal ring having a proximal base and a distal end has a seal ring seal profile between the proximal base and distal end that contacts the tubular member seal profile. A distal annular recess is in one of the seal profiles, the distal annular recess being spaced axially from the distal end of the seal ring, defining a seal surface between the distal end of the seal ring and the distal annular recess that engages a seal surface of the tubular member seal profile. The contacting portions of the seal surfaces form a metal-to-metal seal area. A proximal annular recess in one of the seal profiles is spaced axially from the distal annular recess, defining a support area axially spaced from the metal-to-metal seal area.
Abstract:
A high pressure seal assembly configured for sealing contact with an opposing surface. The seal assembly comprises an annular seal body with a sealing surface on one side of the seal body. An end of the sealing surface includes a sealing face for sealing contact with the opposing surface. The sealing surface also includes at least one support point that contacts the opposing surface when the seal is placed in sealing contact. Strategically positioning the support point on the sealing surface selectively adjusts the sealing contact stress between the sealing face and the opposing surface.
Abstract:
A riser connector uses a box and upset pin connector threadform design having S-shaped load flanks that provide a variable load angles depending on the radial position along the engaged teeth. This design promotes a load path that changes with position along the axial length of the engaged thread, as well as increasing or decreasing external loads on the connector. The connector also varies radial distention of the pin from the box in a manner that is different from one thread to the next. The threadform uses a combination of thread cuts that vary in shape, pitch, and/or thread cone angle to provide load and stab flanks, as well as a load path, that vary from one axial end of the engaged thread to the other.
Abstract:
An offshore riser includes a plurality of tubular elements, each having a pin member on one end and a box member on the other end for connection with adjacent tubular elements. The pin member has an external thread which engages an internal thread on the box member of the adjacent tubular element. A dual angle torque shoulder locks the box end securely into place against the pin, preventing radial distention of the box end and maintaining bearing pressure between the external sealing surfaces. Also, stress relief grooves are located on the box member and on the pin member, to reduce the incidence of stress fractures, thereby improving the fatigue life of the connection.
Abstract:
A tensioner assembly for applying tension to a tubular member, such as a riser, can include an upper latch connected to the tubular member, a platform with a bore, and a plurality of lower latch segments, each having a base that is pivotally connected to the platform. After applying tension to the tubular member, the segments pivot inward to form an annular lower latch ring having an inner diameter less than an outer diameter of the upper latch. The assembly can include a locking mechanism that prevents axial movement of the upper latch, relative to the lower latch ring, after engagement. The upper latch can self-center on the lower latch as it is moved into the latching position.