Subsea termination assembly
A subsea termination assembly comprising a main body, a stab pin with a stabbing end for guiding of the subsea termination assembly during landing on a receiving subsea structure, and a hinge assembly connecting the stab pin to the main body. The subsea termination assembly comprises a connected portion that is pivotably attached to the main body with the hinge assembly. The stab pin comprises a free portion and the free portion comprises the stabbing end. The subsea termination assembly comprises a stab pin connection arrangement, detachably connecting the free portion to the connected portion. A method is also disclosed.
1 . A subsea termination assembly comprising
a main body,
a stab pin with a stabbing end configured to be inserted into a guide funnel of a receiving subsea structure to guide the subsea termination assembly during landing on the receiving subsea structure, and
a hinge assembly connecting the stab pin to the main body,
wherein:
the stab pin comprises a connected portion that is pivotably attached to the main body with the hinge assembly and a free portion that comprises the stabbing end of the stab pin, and
the subsea termination assembly comprises a stab pin connection arrangement detachably connecting the free portion of the stab pin to the connected portion of the stab pin, wherein the stab pin connection arrangement comprises:
an insert section disposed within a bore along a central axis of the bore, wherein a first one of the connected portion of the stab pin or the free portion of the stab pin has the insert section, and a second one of the connected portion of the stab pin or the free portion of the stab pin has the bore; and
one or more bolts or pins configured to extend through one or more first securing apertures in the free portion of the stab pin and one or more second securing apertures in the connected portion of the stab pin to block relative movement and separation of the connected portion of the stab pin and the free portion of the stab pin, wherein the one or more first securing apertures are angularly aligned with the one or more second securing apertures.
2 . The subsea termination assembly according to claim 1 , wherein the hinge assembly comprises a trunnion pin which is attached to the main body, and the stab pin and a yoke are connected to the trunnion pin, such that the yoke and the stab pin can pivot about the trunnion pin.
3 . The subsea termination assembly according to claim 2 , wherein the yoke comprises a lifting eye configured to interface with a lift.
4 . The subsea termination assembly according to claim 1 , wherein the main body is connected to an end of an umbilical configured to transmit electrical signals and fluid.
5 . The subsea termination assembly according to claim 1 , further comprising an angular pin alignment arrangement configured to angularly align the free portion of the stab pin to the connected portion of the stab pin, wherein the angular pin alignment arrangement comprises an alignment protrusion that fits into an alignment slot or notch, and wherein the alignment protrusion and the alignment slot or notch are configured to engage one another in an axial direction over an axial distance along the central axis of the bore during axial engagement between the free portion of the stab pin and the connected portion of the stab pin.
6 . The subsea termination assembly according to claim 1 , wherein the one or more bolts or pins are configured to extend in a radial direction relative to the central axis of the bore through the one or more first securing apertures in the free portion of the stab pin and the one or more second securing apertures in the connected portion of the stab pin.
7 . The subsea termination assembly according to claim 1 , wherein the free portion of the stab pin comprises a landing plate configured to abut against an upper portion of the guide funnel of the receiving subsea structure.
8 . The subsea termination assembly according to claim 1 , wherein the main body is configured to pivot with respect to the stab pin after the stab pin is inserted into the guide funnel of the receiving subsea structure to fully land on the receiving subsea structure.
9 . The subsea termination assembly according to claim 1 , wherein the free portion of the stab pin comprises a guide configured to rotationally align the stab pin with the guide funnel of the receiving subsea structure.
10 . The subsea termination assembly according to claim 9 , wherein the guide of the free portion of the stab pin is disposed between the stabbing end of the stab pin and a landing plate of the free portion of the stab pin, wherein the landing plate of the free portion of the stab pin is configured to abut against an upper portion of the guide funnel of the receiving subsea structure.
11 . A method of installing a subsea termination assembly, having a main body, at a subsea location, comprising the following steps:
a) at a floating structure, installing a utility string, which is connected to the main body, in a tensioning system;
b) attaching a free portion of a stab pin to a connected portion of the stab pin, wherein the connected portion of the stab pin is attached to the main body with a hinge assembly, and wherein the attaching comprises:
inserting an insert section into a bore along a central axis of the bore, wherein a first one of the connected portion of the stab pin or the free portion of the stab pin has the insert section, and a second one of the connected portion of the stab pin or the free portion of the stab pin has the bore; and
inserting one or more bolts or pins into one or more first securing apertures in the free portion of the stab pin and one or more second securing apertures in the connected portion of the stab pin to block relative movement and separation of the connected portion of the stab pin and the free portion of the stab pin, wherein the one or more first securing apertures are angularly aligned with the one or more second securing apertures;
c) lowering the termination assembly from the floating structure towards the seabed;
d) at the seabed, inserting the stab pin into a guide funnel of a receiving subsea structure; and
e) pivoting the main body with respect to the stab pin via the hinge assembly, thus landing the main body onto the receiving subsea structure.
12 . The method according to claim 11 , wherein the utility string is a subsea umbilical configured to transmit electrical signals and fluid.
13 . The method according to claim 11 , wherein step c) comprises suspending the subsea termination assembly through a yoke with a lifting eye, wherein the yoke is configured to pivot, with respect to the main body, about the same pivot axis as the stab pin.
14 . The method according to claim 11 , wherein the one or more bolts or pins extend in a radial direction relative to the central axis of the bore through the one or more first securing apertures in the free portion of the stab pin and the one or more second securing apertures in the connected portion of the stab pin.
15 . A subsea termination assembly comprising
a main body,
a stab pin with a stabbing end configured to be inserted into a guide funnel of a receiving subsea structure to guide the subsea termination assembly during landing on the receiving subsea structure,
a hinge assembly connecting the stab pin to the main body in a pivotable manner, and
a yoke with a lifting eye;
wherein the hinge assembly comprises a trunnion pin which is attached to the main body, the stab pin and the yoke are connected to the trunnion pin, such that the yoke and the stab pin can pivot about the trunnion pin,
wherein the stab pin comprises a free portion comprising the stabbing end, and a connected portion connected to the trunnion pin
wherein the subsea termination assembly comprises a stab pin connection arrangement to detachably connect the free portion of the stab pin to the connected portion of the stab pin,
wherein the stab pin connection arrangement comprises an insert section disposed within a bore along a central axis of the bore, a first one of the connected portion of the stab pin or the free portion of the stab pin has the insert section, and a second one of the connected portion of the stab pin or the free portion of the stab pin has the bore,
wherein the free portion of the stab pin comprises one or more first securing apertures and the connected portion of the stab pin comprises one or more second securing apertures configured to receive one or more bolts or pins to block relative movement and separation of the connected portion of the stab pin and the free portion of the stab pin, and
wherein the stab pin comprises one or more alignment features configured to provide angular alignment of the one or more first securing apertures in the free portion of the stab pin and the one or more second securing apertures in the connected portion of the stab pin to enable insertion of the one or more bolts or pins.
16 . The subsea termination assembly according to claim 15 , wherein the one or more alignment features comprises an alignment notch disposed on the connected portion of the stab pin and an alignment protrusion disposed on the free portion of the stab pin and configured to fit into the alignment notch, wherein the alignment notch and the alignment protrusion are configured to engage one another in an axial direction over an axial distance along the central axis of the bore during axial engagement between the free portion of the stab pin and the connected portion of the stab pin.
17 . The subsea termination assembly according to claim 15 , wherein the one or more bolts or pins extend in a radial direction relative to the central axis of the bore through the one or more first securing apertures in the free portion of the stab pin and the one or more second securing apertures in the connected portion of the stab pin.
18 . The subsea termination assembly according to claim 15 , wherein the free portion of the stab pin comprises a landing plate configured to abut against an upper portion of the guide funnel of the receiving subsea structure.