Rotating control device for jackup rigs
A rotating control device includes a bowl housing with an inner aperture to receive a seal and bearing assembly. A plurality of hydraulically-actuated fail-last-position latching assemblies are disposed about an outer surface of the bowl housing to controllably extend a plurality of piston-driven dogs radially into a groove of the seal and bearing assembly. The seal and bearing assembly includes a housing, a mandrel disposed within an inner aperture of the housing, a first interference-fit sealing element attached to a bottom distal end of the mandrel, a plurality of tapered-thrust bearings indirectly mounted to the housing, a preload spacer disposed between top and bottom tapered-thrust bearings, a plurality of jam nuts to adjust a preload of the tapered-thrust bearings, and a lower seal carrier attached to the seal and bearing housing comprising a plurality of dynamic sealing elements that contact the mandrel.
1. A seal and bearing assembly for a rotating control device for jackup rigs comprising:
a seal and bearing housing;
a rotatable mandrel disposed within an inner aperture of the seal and bearing housing;
an upper seal carrier attached to a top side of the seal and bearing housing comprising a dynamic sealing element that contacts the rotatable mandrel;
a plurality of tapered-thrust bearings to facilitate rotation of the rotatable mandrel, wherein the plurality of tapered-thrust bearings comprise top tapered-thrust bearings indirectly mounted at a positive offset angle from a perpendicular line to a longitudinal axis of the rotating control device and bottom tapered-thrust bearings indirectly mounted at a negative offset angle from the perpendicular line to the longitudinal axis of the rotating control device;
a preload spacer disposed between the top and bottom tapered-thrust bearings; and
a lower seal carrier attached to a bottom side of the seal and bearing housing comprising a plurality of removable seal carrier trays, wherein a plurality of dynamic sealing elements that contact the rotatable mandrel are removably disposed within the plurality of removable seal carrier trays.
2. The seal and bearing assembly of claim 1 , further comprising:
a lubricating grease disposed within the seal and bearing housing to lubricate the plurality of tapered-thrust bearings.
3. The sealed seal and bearing assembly of claim 1 , wherein the top tapered-thrust bearings are indirectly mounted at an offset angle in a range between 10 degrees and 40 degrees from the perpendicular line to the longitudinal axis of the rotating control device.
4. The sealed seal and bearing assembly of claim 1 , wherein the bottom tapered-thrust bearings are indirectly mounted at an offset angle in a range between −10 degrees and −40 degrees from the perpendicular line to the longitudinal axis of the rotating control device.
5. The sealed seal and bearing assembly of claim 1 , wherein the back-to-back orientation of the top and bottom tapered-thrust bearings increases radial stability.
6. A rotating control device for jackup rigs comprising:
a bowl housing comprising an inner aperture to receive a removably disposed seal and bearing assembly; and
a seal and bearing assembly comprising:
a seal and bearing housing,
a rotatable mandrel disposed within an inner aperture of the seal and bearing housing,
an upper seal carrier attached to a top side of the seal and bearing housing comprising a dynamic sealing element that contacts the rotatable mandrel,
a plurality of tapered-thrust bearings to facilitate rotation of the rotatable mandrel, wherein the plurality of tapered-thrust bearings comprise top tapered-thrust bearings indirectly mounted at a positive offset angle from a perpendicular line to a longitudinal axis of the rotating control device and bottom tapered-thrust bearings indirectly mounted at a negative offset angle from the perpendicular line to the longitudinal axis of the rotating control device,
a preload spacer disposed between the top and bottom tapered-thrust bearings, and
a lower seal carrier attached to a bottom side of the seal and bearing housing comprising a plurality of removable seal carrier trays, wherein a plurality of dynamic sealing elements that contact the rotatable mandrel are removably disposed within the plurality of removable seal carrier trays.
7. The rotating control device of claim 6 , further comprising:
an intra-overshot-pipe assembly removably attached to a top distal end of the rotatable mandrel, the intra-overshot-pipe assembly comprising a second interference-fit sealing element,
wherein the intra-overshot-pipe assembly is disposed within an overshot pipe disposed above the rotating control device.
8. The rotating control device of claim 6 , further comprising:
a top flange comprising a top flange lumen attached to a top distal end of the bowl housing; and
a bottom flange comprising a bottom flange lumen attached to a bottom distal end of the bowl housing.
9. The rotating control device of claim 6 , further comprising a shroud to protect protruding portions of hydraulically-actuated fail-last-position latching assemblies.
10. The rotating control device of claim 6 , wherein top tapered-thrust bearings are indirectly mounted at an offset angle in a range between 10 degrees and 40 degrees from the perpendicular line to the longitudinal axis of the rotating control device.
11. The rotating control device of claim 6 , wherein bottom tapered-thrust bearings are indirectly mounted at an offset angle in a range between −10 degrees and −40 degrees from the perpendicular line to the longitudinal axis of the rotating control device.
12. The rotating control device of claim 6 , wherein the back-to-back orientation of the top and bottom tapered-thrust bearings increases radial stability.
13. The rotating control device of claim 6 , wherein a first interference-fit sealing element seals an annulus surrounding the drill pipe.
14. The rotating control device of claim 6 , wherein a second interference-fit sealing element forms a redundant seal to the annulus surrounding the drill pipe.
15. The rotating control device of claim 6 , wherein a first interference-fit sealing element, the rotatable mandrel, and a second interference-fit sealing element rotate with the drill pipe.
16. The rotating control device of claim 6 , wherein a first interference-fit sealing element and a second interference-fit sealing element comprises natural rubber, nitrile butadiene rubber, hydrogenated nitrile butadiene rubber, polyurethane, elastomeric material, or combinations thereof.
17. The rotating control device of claim 6 , wherein a first interference-fit sealing element comprises a first seal lumen having a first seal inner aperture slightly smaller than an outer diameter of the drill pipe and a second interference-fit sealing element comprises a second seal lumen having a second seal inner aperture slight smaller than the outer diameter of the drill pipe.
18. The rotating control device of claim 6 , wherein an overshot pipe is bolted to a top flange of the bowl housing.
19. The rotating control device of claim 10 , wherein the intra-overshot-pipe assembly disposed within the overshot pipe rotates with the mandrel.
20. The rotating control device of claim 6 , wherein a bottom flange of the bowl housing is attached to an annular or blow-out preventer connection disposed below the rotating control device.