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: 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 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.