Patent ID: 8720577
Filing Date: 2014-05-13
Classification: E21B

Abstract:
1. A method of performing operations in a well bore, the method comprising the following steps: (a) attaching a swivel to a drill string, the swivel including a mandrel and a sleeve, the sleeve being rotatably connected to the mandrel with the sleeve including at least one catch that restricts the extent of longitudinal movement of the sleeve related to an annular blow-out preventer by contact with a closed annular seal of the annular blow-out preventer; (b) inserting the swivel into the annular blow-out preventer, the blow out preventer being fluidly connected to a wellbore and a riser; (c) detachably connecting the blowout preventer to the sleeve fluidly separating the riser from the wellbore; (d) during a time period while the blowout preventer is detachably connected to the sleeve and the at least one catch is in contact with the closed annular seal of the annular blow-out preventer, and where high differential pressure exists above and below the annular seal of the annular blow-out preventer, and which high differential force attempts to push the sleeve vertically out of the closed annular seal, performing operations in the wellbore, wherein the at least one catch includes a contacting surface, the contacting surface having at least one opening or groove for allowing fluid flow across at least part of the contacting surface when the annular seal of the annular blowout preventer is closed on and in contact with the contacting surface.