Bellows type adjustable casing
AssigneeVetco Gray Inc.
InventorsFrank C. Adamek, James R. M. Allison
Life of this patent
Estimating the term…
Abstract
A tieback connection between an offshore production platform and a wellhead on the sea floor has a riser and a tubular expandable and contractable member within the riser. The expandable and contractable member compensates for axial movement within the riser while maintaining axial tension in the riser. The expandable and contractable member is of uni-body construction having a wall configured to correspondingly expand and contract to compensate for the riser movement. In cross section, the member wall comprises folds formable by alternating slots formed into the inner and outer wall surface or an undulating surface.
Claims22
A tubular assembly for connection between a platform and a subsea wellhead assembly, the tubular assembly comprising:
- an annular riser for connection between the platform and the subsea wellhead assembly;
- and
- an axially expandable and contractable member connected to the annular riser, the expandable and contractable member comprising a uni-body tubular having a wall formed to axially expand and contract a greater amount per linear increment than the riser.
A compensating casing sub mechanically attachable between a platform and a subsea wellhead assembly, the compensating casing sub comprising:
- a tubular body having an axis;
- and
- a series of expandable and/or foldable segments integrally formed in the body circumscribing the axis and sequentially arranged along a length of the body, so as to allow the body to elastically elongate and contract.
A method of connecting a subsea wellhead assembly and a surface platform, comprising:
- assembling a tubular assembly extending between the subsea wellhead assembly and the surface platform;
- and
- installing an axially expandable and/or contractable tubular member in series with the tubular assembly.
Dependencies are inferred from the claim text.