Patent ID: 8496409

Claim:
A tensioner for maintaining a tensile force in a riser having an axis and extending from a subsea wellhead assembly through an opening in a floating platform deck, the tensioner comprising: a tensioner ring adapted to be coupled to the riser and having an axis; a plurality of hydro-pneumatic cylinders, each having flexible joints on upper and lower ends for coupling the hydro-pneumatic cylinders between the deck and the tensioner ring; the hydro-pneumatic cylinders being pivotal between a running position, wherein the upper ends of the hydro-pneumatic cylinders are pivoted outward from the axis while the riser is lowered through the opening, and a tensioning position wherein the hydro-pneumatic cylinders are pivoted inward toward the axis and coupled to the tensioner ring; and a plurality of mechanical stops for limiting the outward pivotal movement of the hydro-pneumatic cylinders, each of the mechanical stops adapted to be coupled to the deck outboard from a corresponding one of the hydro-penumatic cylinders.