Patent ID: 6161619
Filing Date: 2000-12-19
Classification: E21B

Abstract:
An offshore oil or gas well intervention riser system comprising:a floating surface vessel adapted to be positioned above a well head;a riser extending downwardly from said vessel to said well head;a reel on said vessel for accommodating at least an upper portion of said riser;means including a multiplicity of interconnected segments along at least said upper portion of said riser for enabling at least said upper portion of said riser to bend, said segments being formed with means defining two bending states for said upper portion including a first state in which said upper portion can bend sufficiently to enable winding of said reel and a second state in which said upper portion has a curvature limited to a lesser extent that the curvature of said upper portion in said first state;a compensating deck on said vessel movable vertically thereon to compensate for sea changes and to which said upper portion of said riser is connectable; anda winch on said vessel connected by a winch line to said riser for exerting an upward tension on said riser.