Abstract: A tubular connector connects two tubulars of a string of tubular members. The tubular connector has a pin end tubular member having an axis and a pin end. A pin end flange is positioned on an outer diameter of the pin end and has an undercut adjacent the union of the pin end flange with the pin end. The tubular connector also has a box end tubular member having a box end. A box end shoulder is adjacent the union of the box end with the box end tubular member. The box end shoulder has an undercut thereon. The pin end is secured to the box end so that the pin end tubular member and the box end tubular member are joined, stresses applied to the pin end tubular member and the box end tubular member are distributed through the undercuts.

Abstract: A pipe connection includes a tubular box having an internal threaded section extending from a rim, and a nose receptacle area joining the threaded section. A box seal surface is formed on the nose receptacle area. A tubular pin has a nose area extending from a pin end, and an external threaded section joining the nose area, the external threaded section mating with the internal threaded section. An annular groove is formed on the nose area between the pin end and the external threaded section. A pin seal surface is located at least partially in the groove for engaging the box seal surface to form a metal to metal sealing engagement.

Abstract: A coupler having two degrees of axial freedom couples a hydro-pneumatic cylinder to a tensioner ring of a riser tensioner mounted to a platform. A post extends along an axis of the cylinder and an intermediate sleeve is disposed around the post to form a post annulus. An outer sleeve is secured to the tensioner ring and defines a cavity into which the post and intermediate sleeve are inserted so that an annulus is formed between the sleeve and the outer sleeve. The Outer sleeve is coupled to the intermediate sleeve so that the outer sleeve may pivot on the coupling between the outer sleeve and the intermediate sleeve relative to the intermediate sleeve. The intermediate sleeve is coupled to the post so that the intermediate sleeve may pivot on the coupling between the intermediate sleeve and the post relative to the post.

Abstract: A subsea riser assembly connects two tubular members with axial movement of an outer sleeve. The assembly includes a first tubular member having an end, and a second tubular member having an end with a plurality of box end fingers separated by slots, the second tubular member coaxial with the first tubular member. The end of the first tubular member is inserted into the end of the second tubular member. An outer sleeve having an inner diameter that engages an outer diameter of each box end finger. Axial movement of the outer sleeve relative to the box end fingers causes the inner diameter of the outer sleeve to interact with the outer diameter of the box end fingers, thereby causing the box end fingers to contract radially. The radial contraction of the box end fingers secures the first tubular member to the second tubular member in a made-up position.

Abstract: An anti-rotation system for use in retaining a threaded connection between a pin and a box. The anti-rotation system includes a key that sets in a recess formed in one of the box or pin. The key is selectively in contact with one of the other of the box or pin, and is activated when the threaded connection begins to decouple. The key is profiled and operates in a cam like fashion to wedge itself between the box and pin when these members begin to decouple and prevents further relative rotation.

Abstract: A tubular connector secures two coaxial tubulars using a box and pin connection. A pin end tubular member having an axis and a pin end inserts into a box end tubular member having a box end. A pin end flange formed on an outer diameter of the pin end tubular member receives an end of the box end of the box end tubular member. An inwardly depending flange is disposed on the inner diameter of the box end portion. The inwardly depending flange is spaced apart from the box end planar surface and has a box end shoulder formed at an angle to the axis facing a same direction as the box end planar surface of the box end tubular member. An end of the pin end of the pin end tubular member engages with the inwardly depending flange for compressive load transfer.

Abstract: A pipe connection includes a tubular box having an internal threaded section extending from a rim, and a nose receptacle area joining the threaded section. A box seal surface is formed on the nose receptacle area. A tubular pin has a nose area extending from a pin end, and an external threaded section joining the nose area, the external threaded section mating with the internal threaded section. An annular groove is formed. on the nose area between the pin end and the external threaded section. A pin seal surface is located at least partially in the groove for engaging the box seal surface to form a metal to metal sealing engagement.

Abstract: A tubular connector connects two tubulars of a string of tubular members. The tubular connector has a pin end tubular member having an axis and a pin end. A pin end flange is positioned on an outer diameter of the pin end and has an undercut adjacent the union of the pin end flange with the pin end. The tubular connector also has a box end tubular member having a box end. A box end shoulder is adjacent the union of the box end with the box end tubular member. The box end shoulder has an undercut thereon. The pin end is secured to the box end so that the pin end tubular member and the box end tubular member are joined, stresses applied to the pin end tubular member and the box end tubular member are distributed through the undercuts.

Abstract: A tubular connector secures two coaxial tubulars using a box and pin connection. A pin end tubular member having an axis and a pin end inserts into a box end tubular member having a box end. A pin end flange formed on an outer diameter of the pin end tubular member receives an end of the box end of the box end tubular member. An inwardly depending flange is disposed on the inner diameter of the box end portion. The inwardly depending flange is spaced apart from the box end planar surface and has a box end shoulder formed at an angle to the axis facing a same direction as the box end planar surface of the box end tubular member. An end of the pin end of the pin end tubular member engages with the inwardly depending flange for compressive load transfer.

Abstract: A push-up tensioner for maintaining a tensile force in a riser having an axis couples to a floating platform and maintains the tensile force while the riser tilts variably from the vertical. The tensioner includes a plurality of cylinders having a lower end pivotally coupled to the deck. The cylinders are substantially perpendicular to the deck in the running position and at an angle to the deck in the tensioning position. After running of the riser, a placement assembly moves the cylinders from the running position to the tensioning position. A tensioner ring is run on the riser proximate to an upper end of the cylinders, and the cylinders are then automatically coupled to the tensioner ring.

Abstract: A subsea riser assembly connects two tubular members with axial movement of an outer sleeve. The assembly includes a first tubular member having an end, and a second tubular member having an end with a plurality of box end fingers separated by slots, the second tubular member coaxial with the first tubular member. The end of the first tubular member is inserted into the end of the second tubular member. An outer sleeve having an inner diameter that engages an outer diameter of each box end finger. Axial movement of the outer sleeve relative to the box end fingers causes the inner diameter of the outer sleeve to interact with the outer diameter of the box end fingers, thereby causing the box end fingers to contract radially. The radial contraction of the box end fingers secures the first tubular member to the second tubular member in a made-up position.

Abstract: A coupler having two degrees of axial freedom couples a hydro-pneumatic cylinder to a tensioner ring of a riser tensioner mounted to a platform. A post extends along an axis of the cylinder and an intermediate sleeve is disposed around the post to form a post annulus. An outer sleeve is secured to the tensioner ring and defines a cavity into which the post and intermediate sleeve are inserted so that an annulus is formed between the sleeve and the outer sleeve. The Outer sleeve is coupled to the intermediate sleeve so that the outer sleeve may pivot on the coupling between the outer sleeve and the intermediate sleeve relative to the intermediate sleeve. The intermediate sleeve is coupled to the post so that the intermediate sleeve may pivot on the coupling between the intermediate sleeve and the post relative to the post.

Abstract: A collet assembly connects two tubular members with a rotation of an outer sleeve. The collet assembly includes a first tubular member with a grooved outer diameter end. The end is inserted into a collet having grooved inner and outer diameter surfaces, and an outer annular sleeve is threaded onto the collet. A grooved outer diameter end of a second tubular member is inserted into the collet. The outer annular sleeve is rotated relative to the collet. The rotation causes the collet to partially disengage from the outer annular sleeve and fully engage the grooves of the ends of the first tubular member and the second tubular member, thereby securing the first tubular member to the second tubular member.

Abstract: A push-up tensioner for maintaining a tensile force in a riser having an axis couples to a floating platform and maintains the tensile force while the riser tilts variably from the vertical. The tensioner includes a plurality of cylinders having a lower end pivotally coupled to the deck. The cylinders are substantially perpendicular to the deck in the running position and at an angle to the deck in the tensioning position. After running of the riser, a placement assembly moves the cylinders from the running position to the tensioning position. A tensioner ring is run on the riser proximate to an upper end of the cylinders, and the cylinders are then automatically coupled to the tensioner ring.

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: A hydro-pneumatic tensioner includes a barrel having an inner bore and a pressurized fluid contained within to form at least part of a primary accumulator having a preset volume of gas at a nominal pressure. A piston having a piston rod extending from an aperture in the barrel is slidably carried in the bore of the barrel and is in communication with the pressurized fluid and positioned to increase the fluid pressure when the piston strokes in the direction of the pressurized fluid. A secondary accumulator also has a preset volume of gas at a preselected pressure. A fluid separator maintains functional separation of the fluid volumes of the primary and secondary accumulators when the primary accumulator pressure is less than the preselected secondary accumulator pressure. The fluid separator allows functional combining of the fluid volumes of the primary and secondary accumulators when the primary accumulator pressure equals or is greater than the preselected secondary accumulator pressure.

Abstract: An attachment extends between an outer sleeve and an inner riser pipe where the pipe penetrates the keel of a platform. In one version, the attachment is a conically-shaped with a small diameter ring that engages the riser pipe and a large diameter ring that engages the outer sleeve. This attachment has elements that are very flexible in bending but relatively stiff and strong in axial load. Other versions include flat rings where lateral load is taken directly into tension and compression in the beams, allowing for relatively high lateral load transfer. Both the conically-shaped attachment and the flat ring have a number of variations that provide low bending stiffness but high axial stiffness of the elements. Depending on whether resistance to axial loads, lateral loads, or resistance to combination of both loads is desired, the attachment and the flat ring may be used alone or in combination.

Abstract: An internal tieback connector for connecting a riser from a platform to a subsea wellhead having internal grooves and a casing hanger therein. The connector has an inner body which carries a lower housing adapted to land on the wellhead. A plurality of dogs abut the lower housing and are adapted to engage and lift the inner body relative to the lower housing. An upper housing is carried on the inner body and adapted to force the dogs inward into engagement with the inner body. A plurality of latch members are carried on the inner body and are adapted to engage the internal grooves when the internal is moved upward relative to the lower housing.