WO1999023349A1

WO1999023349A1 - Device for connecting a manifold module and a structure on a seabed

Info

Publication number: WO1999023349A1
Application number: PCT/NO1998/000324
Authority: WO
Inventors: Terje Melbye Hansen; Martin Faella
Original assignee: Kongsberg Offshore A/S
Priority date: 1997-11-03
Filing date: 1998-10-30
Publication date: 1999-05-14
Also published as: NO305666B1; NO975068L; WO1999023349A8; NO975068D0; AU1180499A

Abstract

A device for connecting a manifold module (1) and a structure (13) on a seabed, for recovery of hydrocarbons at sea. The device comprises a steering rod (10) of the manifold module (1) which is arranged for insertion in an upwardly open boring of the structure (13). Via a joint device (7) the steering rod (10) can be pivoted between a first position and a second position, where the steering rod's (10) longitudinal axis in the first position extends substantially perpendicularly relative to the longitudinal axis of the steering rod in the second position.

Description

Device for connecting a manifold module and a structure on a seabed

The invention concerns a device for connecting a manifold module and a structure or base on a seabed, as indicated in the introduction to claim 1.

From the prior art there are known manifold modules which carry a suction anchor on the bottom, the manifold module and the suction anchor being arranged to be lowered from a platform at sea until the suction anchor has been inserted into the seabed for anchoring the manifold module. A disadvantage of this arrangement is that the total height of the manifold and the suction anchor prevent horizontal introduction thereof through a platform opening near the moon pool for lowering the manifold by means of a drill string.

Furthermore, for attachment of a manifold module on the seabed the use is known in the prior art of piles which extend through side structures which project from a central section or frame of the manifold module. Even though the manifold module may then be low, it becomes wide, thus preventing it from being lowered through the moon pool.

The object of the invention is to provide a manifold module which is not encumbered by the above-mentioned drawbacks.

The characteristics of the manifold module according to the invention are presented by the characteristic features indicated in the claims.

The invention will now be described in more detail with reference to the drawing which illustrates an embodiment of the device according to the invention.

The direction indication "up" should hereinafter be understood as the direction towards the edge of the drawing facing away from the reader.

Fig. 1 is a side view of a manifold module with a hinged steering rod, the steering rod being illustrated by solid lines in a first, completely inwardly pivoted position wherein it extends across a pipe socket of the manifold, and by broken lines in a second position, wherein it extends coaxially with an adjacent pipe socket of the manifold, as well as two further positions wherein it extends between the first and the second position, a half of the pipe socket being intersected. Fig. 2 is a side view of the manifold module which is illustrated in fig. 1, where the steering rod is located in the second position.

Fig. 3 is a side view of the manifold module which is illustrated in fig. 2, where the steering rod is retracted into the pipe socket and is arranged over and coaxially with a structure.

Fig. 4 is a side view of the manifold module illustrated in fig. 3, where the steering rod has been inserted in the structure and is connected thereto.

In fig. 1 there is illustrated a section of a frame 2 of a manifold module 1 from which a pipe socket 3 extends downwards. Round the area where the pipe socket 3 is attached to the frame 2 there extend at intervals along the pipe socket's periphery and along a circle a row of radially outwardly projecting lugs 4.

In the centre of the pipe socket 3 there is thereto connected an actuator, e.g. a hydraulic jack 5, whose piston rod 6 is closed at the bottom by a hinge pin 7. To this hinge pin 7 there is pivotably connected a lead-in or steering rod 10, whose upper section has a lug or bracket 11 through which the hinge pin 7 extends.

The manifold module 1 may include a pivoting device (not shown) whereby the steering rod 10 may be pivoted about the hinge pin 7 when the piston rod 6 has been moved axially outwards from the actuator 5, i.e. in the position of the piston rod 6 which is illustrated by solid lines in figs. 1 and 2, i.e. by means of devices which are provided on the manifold module, but it should be understood that the steering rod 10 may instead by pivoted by means of devices which are not provided on the manifold module. By operation of the pivoting device the steering rod 10 can be brought into a position wherein it extends coaxially with the pipe socket 3. Possibly the steering rod 10 may be pivoted by releasing it in the position wherein it is illustrated by solid lines in fig 1 , and brought into the coaxial position by means of its own weight. Fig. 3 illustrates a manifold module 1 whose steering rod 10 is retracted into the pipe socket 3 by means of the jack 5, an upper circumferential section of the steering rod 10 abutting against a lower, inner circumferential section of the pipe socket 3, thus causing the steering rod to be immovably mounted in the pipe socket. It should further be understood that the manifold module 1 has been lowered through a moon pool of a platform at the surface to near a seabed 12, and is suspended a short distance over a structure 13, whereby the manifold module 1 may have been brought into a position wherein the steering rod 10 extends approximately coaxially with the structure 13 by means of, e.g. a remotely operated subsea vessel.

The lower end section of the steering rod 10 has a smaller diameter than the upper end section, and between these end sections the steering rod 10 has a conical transition section 16. At the top the structure 13 has a row of upwardly projecting pins or lugs 15 which are arranged at intervals along a circle along the structure's periphery.

The manifold module 1 may be transported to the platform at sea by means of a supply ship and its steering rod 10 may then have been brought into the inwardly pivoted position which is illustrated by solid lines in fig. 1. The manifold module 1 thereby requires little space and the risk of it being damaged is greatly reduced.

When the manifold module 1 has been suspended in a crane on board the platform in order to be lowered to the structure 13, the steering rod 10 is released and brought from the inwardly pivoted position to the position which is illustrated in fig. 2, whereupon it is retracted into the pipe socket 3 by means of the actuator 5.

The manifold module 1 is then lowered to near the structure 13 and substantially aligned relative thereto, e.g. by means of the remotely operated vessel (not shown), whereupon the manifold 1 is lowered further, thus causing the steering rod 10 to extend into the structure 13. As the lowering continues, the transition section 16 helps to ensure that the steering rod is centred in the structure 13, and finally the lugs 4 on the pipe socket 3 are inserted into the spaces between the lugs 15 and vice versa, thereby ensuring an alignment of the manifold module 1 in a horizontal plane relative to the structure 13.

Even though it has been stated above that the relative alignment of the manifold 1 and the structure in a horizontal plane may be achieved by means of lugs, it will be understood that such an alignment may be achieved in many different ways.

Claims

PATENT CLAIMS

1. A device for connecting a manifold module and a structure (13) on a seabed, for recovery of hydrocarbons at sea, wherein the manifold module (1) and the structure (13) have a first and a second connection device for connecting the manifold module and the structure, wherein the first connection device comprises a steering rod (10), the second connection device comprises an upwardly open boring of the structure (13) for receiving the steering rod (10), characterized in that the steering rod (10) is connected to a frame (2) of the manifold module (1) via a joint device (7) for pivoting the steering rod (10) relative to the frame (2) between a first position and a second position, where the steering rod's (10) longitudinal axis in the first position extends substantially perpendicularly relative to the longitudinal axis of the steering rod (10) in the second position, and that when the steering rod is located in one of the positions, it extends coaxially with a pipe socket (3) which is similarly securely connected to the frame (2), and that the manifold module (1) has an actuator device (5, 6) for movement of an end section of the steering rod (10) located near the pipe socket (3) into or out of the pipe socket (3) when the steering rod is located in this position.

2. A device according to claim 1, characterized in that the manifold module (1) comprises first engagement elements (4) which are arranged to engage with second engagement elements (15) of the structure (13) for alignment of the manifold module (1) in a horizontal plane relative to the structure (13).

3. A device according to claim 2, characterized in that the engagement elements are in the form of lugs (4, 15) which extend at intervals along the pipe socket's (3) periphery and on the structure (13) respectively, the lugs (4) on the pipe socket (3) being arranged for insertion in the spaces between the lugs (15) on the structure.