US 6,554,072 B1 · Co-linear tensioner and methods for assembling production and drilling risers using same

Abstract

A tensioner for providing a conduit, e.g., drilling and production riser strings, from a floating vessel at the surface of the ocean to the blowout preventer stack, production tree, or other assembly which is connected to the wellhead at the sea floor. The tensioner compensates for vessel motion induced by wave action and heave and maintains a variable tension to the riser string alleviating the potential for compression and thus buckling or failure of the riser string. The tensioner of the present invention preferably includes at least one mandrel having at least one hang-off donut; at least one upper flexjoint swivel assembly, at least one radially ported manifold, and at least one tensioning cylinder co-linearly combined in a single unit. Methods for assembling risers are also disclosed.

Claims47

Dependent claims

A tensioner comprising:

at least one mandrel;
at least one upper flexjoint swivel assembly in communication with the at least one mandrel;
at least one manifold in communication with the at least one upper flexjoint swivel assembly, the at least one manifold having a first radial fluid band and a second radial fluid band;
at least one tensioning cylinder having a blind end, a rod end, and at least one transfer tubing, the blind end being in communication with the first radial fluid band, the transfer tubing being in communication with the second radial fluid band and the rod end being in communication with at least one flexjoint bearing;
and
a base in communication with the at least one flexjoint bearing.

3 more elements

A method for assembling a riser having a plurality of tubulars comprising the steps of:

(a) providing a tensioner having a first tensioner end, a second tensioner end, a retracted position, an extended position, at least one mandrel, at least one upper flexjoint swivel assembly in communication with the at least one mandrel, at least one manifold in communication with the at least one upper flexjoint swivel assembly, the at least one manifold having a first radial fluid band and a second radial fluid band, at least one tensioning cylinder having a blind end, a rod end, and at least one transfer tubing, the blind end being in communication with the first radial fluid band, the transfer tubing being in communication with the second radial fluid band, and a base in communication with the rod end of each of the at least one tensioning cylinder;
(b) providing a drilling or production facility having a rig floor and a moonpool disposed below the rig floor, the rig floor including at least one rig floor slip having a rig floor slip opened position and a rig floor slip closed position;
(c) inserting the tensioner through the at least one rig floor slip, through the rig floor, and into the moonpool;
(d) connecting the tensioner to the rig floor;
(e) inserting a first tubular through the at least one rig floor slip, through the rig floor, through the tensioner, and into the moonpool;
(f) disposing the at least one rig floor slip around the first tubular and moving the at least one rig floor slip from the rig floor slip opened position to the rig floor slip closed position, whereby the first tubular is maintained in place by the at least one rig floor slip;
(g) connecting a second tubular to the first tubular thereby forming a riser having a plurality of tubulars;
(h) moving the at least one rig floor slip from the rig floor closed position to the rig floor opened position;
(i) inserting the second tubular through the at least one rig floor slip, through the rig floor, through the tensioner, and into the moonpool;
(j) moving the at least one rig floor slip from the rig floor slip opened position to the rig floor slip closed position, whereby the riser is maintained in place by the at least one rig floor slip;
(k) releasably securing the base of the tensioner to the first tubular;
(l) connecting a third tubular to the second tubular;
(m) moving the at least one rig floor slip from the rig floor closed position to the rig floor opened position;
(n) inserting the third tubular through the at least one rig floor slip, through the rig floor, through the tensioner, and into the moonpool, thereby moving the tensioner from the retracted position to the extended position;
(o) moving the at least one rig floor slip from the rig floor slip opened position to the rig floor slip closed position;
(p) releasing the base of the tensioner from the first tubular, whereby the riser is maintained in place by the at least one rig floor slip;
(q) moving the tensioner from the extended position to the retracted position;
(r) releasably securing the base of the tensioner to the second tubular;
(s) connecting a fourth tubular to the third tubular;
(t) moving the at least one rig floor slip from the rig floor closed position to the rig floor opened position;
(u) inserting the fourth tubular through the at least one rig floor slip, through the rig floor, through the tensioner, and into the moonpool, thereby moving the tensioner from the retracted position to the extended position;
(v) moving the at least one rig floor slip from the rig floor slip opened position to the rig floor slip closed position;
(w) releasing the base of the tensioner from the second tubular, whereby the riser is maintained in place by the at least one rig floor slip;
(x) moving the tensioner from the extended position to the retracted position;
and
(y) releasably securing the base of the tensioner to the third tubular.

23 more elements

A method for assembling a riser having a plurality of tubulars comprising the steps of:

(a) providing a tensioner having a first tensioner end, a second tensioner end, a retracted position, an extended position, at least one mandrel, at least one upper flexjoint swivel assembly in communication with the at least one mandrel, at least one manifold in communication with the at least one upper flexjoint swivel assembly, the at least one manifold having a first radial fluid band and a second radial fluid band, at least one tensioning cylinder having a blind end, a rod end, and at least one transfer tubing, the blind end being in communication with the first radial fluid band, the transfer tubing being,in communication with the second radial fluid band, and a base in communication with the rod end of each of the at least one tensioning cylinder;
(b) providing a drilling or production facility having a rig floor and a moonpool disposed below the rig floor, the rig floor having at least one rig floor slip having a rig floor slip opened position and a rig floor slip closed position;
(c) inserting a first tubular through the at least one rig floor slip, through the rig floor, and into the moonpool;
(d) moving the at least one rig floor slip from the rig floor slip opened position to the rig floor slip closed position, whereby the first tubular is maintained in place by the at least one rig floor slip;
(e) connecting a second tubular to the first tubular thereby forming a riser having a plurality of tubulars;
(f) moving the at least one rig floor slip from the rig floor closed position to the rig floor opened position;
(g) inserting the second tubular through the at least one rig floor slip, through the rig floor, and into the moonpool;
(h) moving the at least one rig floor slip from the rig floor slip opened position to the rig floor slip closed position, whereby the riser is maintained in place by the at least one rig floor slip;
(i) providing at least one spider beam, the at least one spider beam having at least one spider beam slip having a spider beam slip opened position and a spider beam slip closed position;
(j) disposing the at least one spider beam slip around the riser and moving the at least one spider beam slip from the spider beam slip opened position to the spider beam slip closed position;
(k) moving the at least one rig floor slip from the rig floor slip closed position to the rig floor slip opened position, whereby the riser is maintained in place by the at least one spider beam slip;
(l) lowering the tensioner over the riser, through the rig floor, and into the moonpool, whereby the riser passes through the tensioner;
(m) connecting the tensioner to the rig floor;
(n) releasably securing the base of the tensioner to the riser;
and
(o) moving the at least one spider beam slip from the spider beam slip opened position to the spider beam slip closed position, whereby the riser is maintained in place by the tensioner.

13 more elements

A method for assembling a riser having a plurality of tubulars comprising the steps of:

(a) providing a tensioner having a first tensioner end, a second tensioner end, a retracted position, an extended position, at least one mandrel, at least one upper flexjoint swivel assembly in communication with the at least one mandrel, at least one manifold in communication with the at least one upper flexjoint swivel assembly, the at least one manifold having a first radial fluid band and a second radial fluid band, at least one tensioning cylinder having a blind end, a rod end, and at least one transfer tubing, the blind end being in communication with the first radial fluid band, the transfer tubing being in communication with the second radial fluid band, and a base in communication with the rod end of each of the at least one tensioning cylinder;
(b) providing a drilling or production facility having a rig floor and a moonpool disposed below the rig floor, the rig floor having at least one rig floor slip having a rig floor slip opened position and a rig floor slip closed position;
(c) inserting a first tubular through the at least one rig floor slip, through the rig floor, and into the moonpool;
(d) moving the at least one rig floor slip from the rig floor slip opened position to the rig floor slip closed position, whereby the first tubular is maintained in place by the at least one rig floor slip;
(e) providing at least one spider beam, the at least one spider beam having at least one spider beam slip having a spider beam slip opened position and a spider beam slip closed position;
(f) disposing the at least one spider beam slip around the first tubular and moving the at least one spider beam slip from the spider beam slip opened position to the spider beam slip closed position;
(g) moving the at least one rig floor slip from the rig floor slip closed position to the rig floor slip opened position, whereby the first tubular is maintained in place by the at least one spider beam slip;
(h) lowering the tensioner over the first tubular, through the rig floor, and into the moonpool, whereby the first tubular passes through the tensioner;
(i) connecting the tensioner to the rig floor;
(j) releasably securing the base of the tensioner to the first tubular;
(k) moving the at least one spider beam slip from the spider beam slip closed position to the spider beam slip opened position, whereby the first tubular is maintained in place by the tensioner;
(l) connecting a second tubular to the first tubular thereby forming a riser having a plurality of tubulars;
(m) moving the at least one rig floor slip from the rig floor closed position to the rig floor opened position;
(n) inserting the second tubular through the at least one rig floor slip, through the rig floor, through the tensioner, and into the moonpool, thereby moving the tensioner from the retracted position to the extended position;
(o) moving the at least one rig floor slip from the rig floor slip opened position to the rig floor slip closed position;
(p) releasing the base of the tensioner from the riser, whereby the riser is maintained in place by the at least one rig floor slip;
(q) moving the tensioner from the extended position to the retracted position;
and
(r) releasably securing the base of the tensioner to the riser.

16 more elements

Dependencies are inferred from the claim text.

Co-linear tensioner and methods for assembling production and drilling risers using same

Life of this patent

Co-linear tensioner and methods for assembling production and drilling risers using same

Life of this patent

Abstract

Claims47