DOWNHOLE SWIVEL APPARATUS AND METHOD

摘要

What is provided is a method and apparatus which can be detachably connected to an annular blowout preventer thereby separating the drilling fluid or mud into upper and lower sections and allowing the fluid to be displaced in two stages, such as while the drill string is being rotated and/or reciprocated. In one embodiment the sleeve can be rotatably and sealably connected to a mandrel. The swivel can be incorporated into a drill or well string and enabling string sections both above and below the sleeve to be rotated in relation to the sleeve. In one embodiment the drill or well string does not move in a longitudinal direction relative to the swivel. In one embodiment, the drill or well string does move longitudinally relative to the sleeve of the swivel.

主权项

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 having a longitudinal axis and a sleeve, the sleeve being rotatably connected to the mandrel, and the sleeve including at least one catch that restricts the extent of longitudinal movement of the sleeve relative to a vertical position of 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 the annular seal of the annular blowout preventer in the riser, and below the annular seal of the annular blow-out preventer in the wellbore, 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, and the contacting surface being substantially perpendicular to the longitudinal axis of the mandrel.