EP0107842A1 - Device for repeatedly carrying out the operations of installing or withdrawing an autonomous submersible module comprising a section of a conduit connectable to a flow-line - Google Patents

Abstract

The collection (3) is arranged on the bottom and the connection of said section (14) with the collection taking place by bringing the ends to be connected end to end, said section being carried by a cradle (7) comprising means displacement allowing the end (13) of said section to exit the module and go at least until contact with the end (5) of the collection to make the connection and to go back by pulling on the collection , the device being characterized in that the end of said collection is placed inside a fixed and rigid sheath (6) of an internal section greater than the section of collection (3) said sheath comprising at least a curved portion and said collection being fixed to said sheath only in the vicinity of the end (8) of the sheath furthest from said module allowing movement of the collection in the sheath.

Description

The document FR-A 2,500,525 describes an underwater petroleum production installation which comprises well heads each associated with an auxiliary module comprising movable members such as valves. This auxiliary module is connected on one side to the well head and on the other to a collection leading to a central structure bringing together all the collections and comprising specialized accessory modules. The auxiliary module can be raised to allow maintenance and repair operations to be carried out on the surface. It is therefore necessary that there is a certain clearance between, on the one hand, this module and the wellhead and, on the other hand, this module and said collection once this module is disconnected from these two elements. However, the internal channel, formed by the collection must be able to continue up to the head of the well without any drop, groove, bump or narrowing of the conduit at the location of the connectors because it must be able to send tools there, which implies end-to-end connections until contact with the ends of the parts to be connected. Taking into account this and the play necessary to allow the arrival and the removal of the auxiliary module, this means that during the connection, we are led to fetch the end of the collection located outside the auxiliary module to pull it inward so that you can make the connection on the other side between the auxiliary module and the wellhead. In view of the fact that, given the dimensions of the modules and the radius necessary for the curves of the conduits, because of the tools which must be able to circulate therein, it is not possible to make up for the said clearances by conduits comprising loops giving them a certain elasticity placed in the auxiliary module or in the wellhead module, the collection is used. Thus, the auxiliary module according to the aforementioned document comprises a cradle which can be moved laterally, this cradle comprising the pipe section to be connected on the one hand to the collection and on the other hand to the wellhead.

However, a difficulty stems from the fact that said collection, and particularly near its end, can be more or less pressed in over time and this can make disconnection impossible because, since the collection is buried, we can no longer count on its flexibility to push its end outwards by lateral movement of said cradle and thus ensure the minimum clearance necessary for raising the module.

The object of the present invention is to overcome this drawback and has as its object a device for repetitively carrying out operations for installing or removing a submersible autonomous module comprising a section of pipe connectable to a collection disposed on the bottom, the connection of said section with the collection being made by approaching until the end-to-end contact of the ends to be connected, said section being carried by a cradle comprising displacement means allowing the end of said section to exit the module and to go at least until contact with the end of the collection to make the connection and to go back by pulling on the collection, characterized in that the end of said collection is placed inside a fixed and rigid sheath, of an internal section greater than the external section of the collection, said sheath comprising at least one curved portion and said collection being fixed to said sheath only vicinity of the end of the sheath furthest from said module, allowing movement of the collection in the sheath.

According to a preferred implementation of the invention, the end of the sheath located on the side of said module is positioned in a sheath comprising means for blocking the sheath, said sheath comprising means for locking the collection in a retracted position , means for unlocking said collection being provided.

• La figure 1 représente d'une manière schématique une tête de puits de production pétrolière sous-marine avec un module auxiliaire, une collecte de transport du produit brut et un dispositif selon l'invention.
• La figure 2 représente la même structure que la figure 1 mais dans une position où la collecte est raccordée au module auxiliaire et ce module à la tête de puits assurant la continuité du canal (ou des canaux) internes de la collecte.
• Les figures 3, 4, 5 et 6 représentent dans différentes positions et de façon plus détaillée le dispositif de connexion de la collecte avec le module auxiliaire et le dispositif de verrouillage et de déverrouillage de la collecte par rapport à la gaine.

The invention will be better understood in the light of the description of an exemplary embodiment of the invention given below with reference to the appended drawing in which:

• FIG. 1 schematically represents a wellhead for underwater petroleum production with an auxiliary module, a collection for transporting the raw product and a device according to the invention.
• Figure 2 shows the same structure as Figure 1 but in a position where the collection is connected to the auxiliary module and this wellhead module ensuring the continuity of the internal collection channel (s).
• Figures 3, 4, 5 and 6 show in different positions and in more detail the device for connecting the collection with the auxiliary module and the device for locking and unlocking the collection relative to the sheath.

Referring to Figures 1 and 2, the assembly includes a wellhead 1, an auxiliary module 2 generally comprising valves and other movable members which may be subject to overhaul or repair, which implies that this module must be able to be put in place and removed repeatedly, and a collection 3 may also consist of several joined pipes. The wellhead 1 and the auxiliary module 2 are positioned and fixed on a base 4. To allow the auxiliary module 2 to be placed and removed, it is necessary to provide in the disconnected position, as is the case in FIG. 1 , a minimum clearance e on the one hand between this module and the well head 1 and on the other hand between this module 2 and the end of a male connector 5 situated at the end of the collection 3.

According to the invention, the end of the collection 3 passes through a sheath 6 which serves as clearance at the end of the collection, thus making it possible, as seen in FIG. 2, once the connection has been made, to pull on the collection. thanks to a carriage 7 located in the module 2 and come to make the connection between the wellhead 1 and the auxiliary module 2. To allow this movement, the sheath 6 is rigid and has a wavy shape as seen in the figures 1 and 2 and its internal section is clearly greater than the external section of the collection 3. In addition, the collection 3 is fixed at 8 to the sheath 6 at its end furthest from the module 1. The opposite end of the sheath 6 is positioned and fixed in a sheath 9 fixed itself on the base 4. A fixing means such as a lock 10 fixes the sheath 6 in its sheath 9. At the other end, the sheath 6 rests on the seabed 11 and collecting 3 courses on the seabed to reach another body located for example on a central structure bringing together organs common to satellite well heads.

The sheath 6 comprises means, shown diagrammatically at 12 in FIGS. 1 and 2 and detailed in FIGS. 3 to 6, for locking the collection 3 in the retracted position, that is to say in the position shown in FIG. 1. Means allow this collection to be unlocked when the female connector 13, associated with the pipe section 14 secured to the carriage 7, approaches the male connector 5 to make the connection.

In practice, the inherent elasticity of the collection 3 means that it tends to move into the extended position, that is to say as shown in FIG. 2, and that the carriage must exert an effort to return it to the position retracted and locked as shown in Figure 1. It is thus seen that thanks to the invention, it is certain to be able to push the collection in its sheath into its locked position (Figure 1) and thus obtain the minimum clearance and allowing to extract the module 2, while in the absence of the sheath 6 one can never be certain of being able to push the collection back into the sheath 9 because it may very well over time have been covered thereby blocking any movement.

With reference to FIGS. 3 to 6, the locking and unlocking system of the collection 3 in its sheath 6 will be described.

In Figure 3, there is shown on the right side the end of the collection 3, in this case consisting of two pipes, to which is fixed a connection member 5 called male connector. We also see on this straight part the end of the sheath 6 comprising at the end the assembly 12 for locking the collection 3 in its sheath 6. In this figure, the sheath 9 has not been shown in which any the end of the sheath. On the left side of the figure, the female connector 13 is shown.

This essentially comprises a body 15 fixed to the pipe section 14 (not shown in this figure) identical to the collection 3 and a sliding ring 16 comprising oblique lights 17 serving as guide ramps allowing the movement of a series of locking fingers 18 through holes 19 made in the body 15 allowing the fingers 18 to move radially.

The locking assembly 12 of the collection 3 in the sheath 6 comprises a body 20 fixed to the end of the sheath 6. This body 20 has a series of holes 21 whose axes are radial relative to the axis of the connector male 5. In each of these holes is placed a pawn of blocking 22 whose cone-shaped end cooperates in the collection blocking position 3 in the sheath 6 with complementary conical holes 23 made in the periphery of the male connector 5. To prevent the blocking pins 22 from coming out of the holes 23, a sliding ring 24 pushed by a spring 25 covers the fingers 22. In order to be able to unlock the collection of its sheath, the sliding ring 24 comprises a groove 26 allowing, when the ring 24 is pushed to the right, the groove being opposite the pins 22 to unlock the system, the pins naturally emerging from the oblique holes 23 by the simple effect of the push of the collection or the tensile force exerted by the carriage 7 once the connection has been made.

In Figure 3 the collection is therefore in the locked position and the assembly is disconnected. The connection and unlocking are then carried out in the following manner: the carriage 7 is moved to the right in the direction of the arrow F until one is in the position shown in FIG. 4 in which the face 27 of the body 15 abuts against the front face 28 of the male connector 5. The sliding ring 16 is then moved to the right so as to force the pins 18 to penetrate the holes 19 and thus take support against the oblique face 29 of the end of the male connector 5, thus making the connection and the sealed continuity without interruption of the internal channels 30 and 31 of the collection 3. The sliding of the ring is carried out hydraulically by conventional means not shown and controlled at the surface by l 'Intermediate of an umbilical cord running along the cable for laying the module 2 and the end of which comprises a tool for handling the module as described in the document FR-A 2500 525 cited above. We are then in the position shown in FIG. 5 and we see that during the displacement of the sliding ring 16, the latter came to bear against the end of the sliding ring 24 pushing it towards the right compressing the spring 25 and placing the groove 26 in front of the pins 22. In this position, the connection is made and the collection is unlocked, it only remains to move the carriage to the left in the direction of the arrow F1 (FIG. 6), to go on the other side to make the connection between the well head 1 and the auxiliary module 2, the rigid sheath 6 allowing a large clearance, without risk of blocking, of the collection 3. During this operation, the pins 22 deviate radially, penetrating into the groove 26; at the same time, the sliding ring 24 returns to the left pushed by the spring 25 until the inclined shoulder 32 of the groove 26 abuts against the beveled end 33 of the pins 22.

• On commence, avant de déplacer le chariot 7 vers la droite, par déplacer la bague coulissante 16 vers la gauche ce qui a pour effet de hisser les doigts le long de la rampe 17 et de débloquer la connexion, mais ce qui a surtout pour effet de faire en sorte qu'en suite, en déplaçant le chariot vers la droite pour venir repousser et verrouiller la collecte dans la gaine, la bague 16 ne vienne pas toucher la bague coulissante 24. Cela permet ainsi de pousser la collecte vers la droite jusqu'à ce que les trous 23 viennent se placer en face des pions 22 et alors à ce moment là, grâce à l'effort du ressort 25 à demi comprimé et aux biseaux 32 et 33, la bague coulissante 24 est repoussée vers la gauche et les pions 22 viennent alors pénétrer dans les trous 23. Le chariot 7 peut alors repartir vers la gauche.

When it is desired to take out the module 2 for maintenance and therefore to carry out the disconnection and the locking of the collection 3 in the sheath 6 so as to obtain the minimum clearance required, the procedure is as follows:

• We start, before moving the carriage 7 to the right, by moving the sliding ring 16 to the left, which has the effect of hoisting the fingers along the ramp 17 and unlocking the connection, but which mainly has the effect to ensure that, subsequently, by moving the carriage to the right to push back and lock the collection in the sheath, the ring 16 does not come to touch the sliding ring 24. This thus makes it possible to push the collection to the right up to '' that the holes 23 are placed in front of the pins 22 and then at this time, thanks to the force of the half-compressed spring 25 and the bevels 32 and 33, the sliding ring 24 is pushed to the left and the pins 22 then come into the holes 23. The carriage 7 can then start to the left.

It is obvious that the locking and unlocking system described is given only by way of example but that any other system, for example a jack, can be used.

Claims (2)

CLAIMS 1 / Device for repetitively carrying out operations for setting up or removing a submersible autonomous module (2) comprising a pipe section (14) connectable to a collection (3) disposed on the bottom ( 11), the connection of said section (14) with the collection being effected by bringing the ends to be connected end to end, said section being carried by a cradle (7) comprising displacement means allowing the end ( 13) of said section leaving the module and going at least to contact with the end (5) of the collection to make the connection and to go back by pulling on the collection, characterized in that the end of said collection is placed inside a fixed and rigid sheath (6), of an internal section greater than the collection section (3) said sheath comprising at least one curved portion and said collection being fixed to said sheath than in the vicinity of the end ( 8) of the sheath furthest from said module allowing movement of the collection in the sheath. 2 / Device according to claim 1, characterized in that the end of said sheath, located on the side of said module, is positioned in a sheath (9) comprising locking means (10) of the sheath, said sheath comprising means locking (12) of the collection in a retracted position, means for unlocking said collection being provided.

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