Arrangement for preventing collection of debris and cuttings on the top of a riser closure device
AssigneeEnhanced Drilling AS
InventorPer Christian Stenshorne
Life of this patent
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Abstract
An arrangement and a method for preventing collection of debris on or for removing debris, such as cuttings, from the top of a closed riser sealing device (215) in a subsea riser (1). The arrangement comprises a flushing line and at least one flushing fluid inlet (294) to direct a jet of flushing fluid into said riser (1). The inlet (294) directs flushing fluid into a space in the riser (1) immediately above said closing element. The invention also relates to a swirl element (351) located immediately above the riser sealing device (215) and being rotationally coupled to a drillstring (11).
Claims18
An arrangement comprising:
- a riser defining a longitudinal bore;
- a riser sealing element;
- wherein the riser sealing element has a closed position, the closed position either closing the longitudinal bore around a string arranged within the riser or completely sealing the longitudinal bore;
- wherein the arrangement is adapted to prevent collection of debris on or for removing debris from the top of the riser sealing element when the riser sealing element is in the closed position;
- a flushing line and a plurality of fluid flushing inlets into the longitudinal bore, the plurality of fluid flushing inlets directing a jet of flushing fluid into the longitudinal bore immediately above the closed riser sealing element wherein the flushing line branches off from a boost line extending along the riser;
- and
- wherein the plurality of fluid flushing inlets are connected to a distribution line, which distribution line is branched off from the boost line.
An arrangement for preventing collection of debris on or for removing debris from the top of a closed riser sealing device in a subsea riser, comprising a swirl element located immediately above the riser sealing device, the swirl element being rotationally coupled to a drill string but being allowed to slide axially with respect to the drill string.
A method for preventing collection of debris on or for removing debris from the top of a closed closing element in a subsea riser, wherein the debris is agitated by a jet of fluid being injected into a space in the riser immediately above the closing element, to stir up any debris from the top of the closing element, wherein the fluid to produce the jet is injected through a flushing line that branches off from an external line extending along the riser, wherein the agitation is assisted by a swirl element rotationally coupled to a drill string.
Dependencies are inferred from the claim text.