Patent ID: 9022127
Filing Date: 2015-05-05
Classification: E21B

Abstract:
1. A workover riser system comprising: a riser extending from a subsea wellhead to a surface vessel, a riser tensioner connected between the vessel and an upper end portion of the riser for keeping the riser tensioned, an upper workover riser package (UWRP) which is located in the upper end portion of the riser below where the riser tensioner is connected to the riser and which together with the riser defines a riser passage extending from the wellhead to the surface vessel, the UWRP comprising a housing within which a number of closure elements for sealing off the riser passage are positioned, wherein the UWRP comprises an inner profile to which each of a plurality of interchangeable workover equipment modules is releasably latched, the modules being configured to be lowered through the upper end portion of the riser and being adapted for sealing around a wire line or a coiled tubing while allowing the wire line or coiled tubing to pass down into the riser, and wherein during use of the riser system, while the UWRP is connected to the riser and supported by riser tensioner in a stationary position relative to the seabed, one of said modules is lowered through the upper end portion of the riser and latched to the inner profile to thereby secure the module to the UWRP.