WO1993013977A1

WO1993013977A1 - Device for the manipulation of a flexible elongated member

Info

Publication number: WO1993013977A1
Application number: PCT/NO1993/000005
Authority: WO
Inventors: Kåre SYVERTSEN
Original assignee: Marine Consulting Group As
Priority date: 1992-01-20
Filing date: 1993-01-07
Publication date: 1993-07-22
Also published as: ATE139192T1; EP0621842A1; DK0621842T3; GR3020224T3; NO920251D0; AU3463693A; NO174381C; FI943417A; DE69303156D1; EP0621842B1; FI943417A0; AU663162B2; ES2088665T3; DE69303156T2; NO920251L; NO174381B

Abstract

An apparatus for handling and storing a bendable elongate body in extended horizontal position, preferably a length of flexible pipeline (3) intended for fluid conduction. The apparatus comprises a guide track (8) and carriers (10) slidably disposed in the guide track for carrying/supporting the bendable elongate body (3).

Description

DEVICE FOR THE MANIPULATION OF A FLEXIBLE ELONGATED MEMBER.

The invention relates to an apparatus for handling an storing a bendable elongate body in extended horizontal position, preferably a length of flexible pipeline intende for fluid conduction.

The invention was developed primarily in connection with the need for a fluid transfer system between a maritime floating oil storage facility, for example a large-size barge with oil storing capacity, and a so-called shuttle tanker. The oil tank barge is anchored or dynamically positioned on the oil production field and serves as an intermediate storage means for the oil produced. From this barge the oil is loaded over into tankers, which on arrival at the field are connected to the barge by suitable mooring means, whereafter a fluid conducting pipe connection is established between the barge and tanker. The fluid conducting pipe connection is formed by a length of fluid conducting pipeline which, when not in use, is stored on the barge. During fluid transfer, the flexible pipeline hangs suspended between the barge and tanker, more or less submerged in the water, or if desired is freely suspended above the water surface.

The length of flexible pipeline is advantageously stored in extended horizontal position on the deck of the barge. When the flexible pipeline is to be utilized for fluid transfer between the barge and tanker, the flexible pipe is fed down into the water from its horizontal storage position on board the barge via a ramp curved downward in the vertical plane. Conversely, after completion of the fluid transfer, the pipeline is uncoupled and drawn on board the barge again. The handling of the flexible length of pipeline during the transition between its storage and usage states can lead to difficulties due to the fact that it involves a flexible pipeline which must be handled in a relatively gentle manner and which, in both handling and storage, requires an evenly distributed support means along the length of the pipeline, spaced at moderate intervals. A continuous support, such as would be provided, for example, if the pipeline were to be laid directly on the barge deck, is undesirable because the feeding out/hauling in of the pipeline would generate too much friction between the pipeline and the supporting deck surface. Lifting of the pipeline and its manipulation in the longitudinal direction with the aid of crane equipment Is highly undesirable as well as impossible to implement in practice. Here one must bear in mind that we are dealing with a flexible pipeline having a length of, e.g., 50 m and more.

Therefore, there is a need for an apparatus for handling and storing a length of flexible pipeline such as described above, which apparatus enables a gentle and relatively friction-free handling of the pipeline, at the same time as the pipeline will also be supported in an adequate manner during storage.

According to the invention, therefore, an apparatus is proposed for feeding and storing a bendable, elongate body in extended, horizontal position, preferably a length of flexible pipeline intended for fluid conduction, comprising a guide track having support means for the bendable elongate body, which apparatus is characterized in that the support means are constructed as carriers in the guide track, slidable in the longitudinal direction thereof, for bearing the bendable elongate body.

The use of slidable carriers in a guide track affords a means of handling (transport) with little frictional resistance, at the same time as the carriers spaced at suitable intervals will provide the necessary bearing or support of, for example, a length of flexible pipeline, not only during movement, but also during the actual storage thereof.

A particularly advantageous embodiment of the apparatus according to the invention is one where the guide track comprises a storage section, where the carriers are stored when not in use, and a horizontal bearing section, where the carriers are situated when in use and bearing said elongate body.

Such an embodiment affords the advantage that when, for example, a length of flexible pipeline is being fed out, the carriers may be steered away from and out of supporting contact with the length of pipeline when it is, for example, lowered into the sea via a suitable ramp. Conversely, the carriers may be brought into supporting contact with the pipeline when it is hauled in and passes from the ramp and over into the horizontal bearing section (for storage).

A further and particularly advantageous improvement on this apparatus is the construction of said storage section as a section of track line extending diagonally downward from one end of the horizontal bearing section.

The advantage of such an embodiment of the apparatus is that the carriers when leaving the horizontal bearing section will slide down along the diagonal downward-extending track line section, where they will be lined up, ready for later use when the pipeline is hauled in.

A particularly expedient embodiment of the apparatus is one where the guide track is arranged with its horizontal bearing section on level with a support path for the body, with said sloping storage section extending down under the support path. When the carriers bearing the pipeline thereon approach the support path, said carriers will be diverted down into the storage section, while the pipeline continues onto the support path. This support path advantageously comprises a ramp section curved downward in the vertical plane, along which the pipeline is lowered down into the water and, conversely, is drawn up.

The carriers slide down into the storage section, as mentioned above, and will remain there, ready for reuse when the pipeline is drawn up (hauled in). The carriers may then be brought successively from the storage section into supporting contact with the pipeline and pass over into the horizontal bearing section, which forms the storage area. In this connection it may be particularly advantageous for the carriers to be coupled to a flexible, elongated drive member, for example a chain, running in the longitudinal direction of the body or pipeline. After a first carrier is brought into supporting contact with the pipeline and the pipeline is drawn further into the bearing section, sub¬ sequent carriers will in this manner be successively drawn out from the storage section and brought into supporting contact with the bearing section and into sliding contact with the part of the track line in the horizontal bearing section.

A simple and reliable arrangement according to the invention is distinguished by each carrier being formed as a cradle adapted to the circumferential shape of the elongate body, having running wheels at each end of the cradle for movement on/in the guide track.

The cradle will provide the required support for the body or pipeline, and one will achieve the desired support at suitable longitudinal intervals by arranging the cradles to have the desired and appropriate spacing, preferably coupled to the aforementioned chain or the like. At the transition into the storage section, the upwardly open cradle form will immediately permit the cradle (carrier) to be released from its bearing engagement with the body or pipeline and to pass down into the storage section; conversely, the• cradles will gain supporting contact with the underside of the body or pipeline when the latter is hauled in again.

Hence, with the invention one obtains a constructively simple and reasonable apparatus that provides a favorable means of handling and storing a bendable, elongate body in extended horizontal position. Said body, for example a length of flexible pipeline, may easily be let out or hauled in with the aid of winches and associated cables. No special measures or operations are required in connection with establishing contact between the individual carriers and the length of pipeline or, conversely, breaking this supporting contact.

The apparatus according to the invention may advantageously include a winch to be used for hauling in and feeding out the body, and an auxiliary winch to be used to initiate the discharge, for pulling the body or pipeline far enough out that its own weight causes the body/pipeline to glide further out by itself, held in check by the main winch.

The invention will now be explained in further detail with reference to the drawings, where:

Fig. 1 is a side view of a barge where a length of pipeline lies stored in extended horizontal state when not in use, Fig. 2 is a schematic horizontal view of the barge in

Fig. 1., Fig. 3 shows the apparatus according to the invention in side view, Fig. 4 shows, on somewhat larger scale, a section of the apparatus in Fig. 3, more specifically a storage section for the carriers, Fig. 5 is a sectional elevation of a cradle-shaped carrier, Fig. 6 is a side view of the carrier in Fig. 5,

Fig. 7 is a top view of the carrier in Fig. 5, and

Figs. 8, 9 and 10 show potential embodiment forms of brackets for supporting a guide track, having a cradle running therealong with the associated pipeline borne thereon.

In Figs. 1 and 2 is shown a barge 1, on the deck 2 of which is placed an apparatus for storing a length of flexible pipeline 3. This pipeline length 3 may be moved rearward (to the left in Figs. 1 and 2) and lowered down into the water via a suitable ramp 4, so that pipeline 3 may thereby be fed down into the water, as indicated by the dotted line in Fig. 1 below ramp 4. •

The actual apparatus is shown in more detail in Fig. 3. Ramp 4 is positioned at the stern end of barge 1 and forms a support path for flexible pipeline 3. The visible end of the flexible pipeline is provided with a connector head 5, from which a cable 6 extends to a winch 7. From the terminating upper section of ramp 4 a guide track 8 extends in the direction toward winch 7, which track is sufficiently long to receive the entire length of pipeline 3. The length of pipeline 3 may be, for example, as long as 50 m or more.

At the point where ramp 3 and guide track 8 converge, the guide track slants downward, thus providing a diagonal track line section 9 extending down under ramp 4. This diagonal, downward extending track line section forms a storage section where carriers 10 may be stored when not in use. These carriers 10 are designed for sliding movement in guide track 8 to bear or support pipeline 3 during its movement into the storage section formed by the guide track. Carriers 10 are connected together by means of a chain 11, so that all the carriers thus constitute elements of one chain of carriers. - 1 -

When the end 5 of the pipeline reaches the area where th diagonal storage section 9 passes over into the horizonta bearing section 8, a first carrier 10 is brought into contac with the pipeline end from underneath. As winch 7 via cabl

6 pulls pipeline 3 further toward the right in Fig. 3, th carriers will gradually be drawn successively up along th track section 9, and one by one come into supporting contac with the underside of the moving pipeline 3. When the end of pipeline 3 has reached the termination of guide track 8, at the end where winch 7 is located, the entire pipeline will be stored, suspended on the carriers 10 hanging on guid track 8. Now the flexible pipeline 3 will rest in th storage area until the next time it is needed. The end o the pipeline, not shown, is then connected to a cable running to an auxiliary winch 12. This is done not b direct coupling to the pipeline, but by the coupling of winch

12 to the nearest carrier 10. With the aid of winch 12, the carriers 10 are pulled toward the left in Fig. 3, during which process pipeline 3 will move toward the left and gradually assume a position as indicated in Fig. 3. A while before this position is reached, the weight of pipeline 3 will cause the pipeline to glide out by itself onto ramp 4, constructed as a roller ramp, and as the pipeline is fed further out it is held in check by means of cable 6 from winch 7.

The actual guide track and carriers will now be explained in more detail, with particular reference to Figs. 4-10.

As shown in Figs. 4-7, guide track 8 consists very simply of two parallel extending angle beams 13, 14, or similar structures. These run parallel to other, spaced apart, and on the horizontal beam flanges are securely welded respec¬ tive track profiles 15, 16. These form respective runways for running wheels 17, 18 on carrier 10. Each carrier 10 is formed as a cradle, with a respective running wheel 17, 18 at each end. The cradle shape is adapted to- the circum¬ ferential shape of pipeline 3; see, for example, Fig. 8.

As shown in Fig. 1, the guide track may be straight, or it may be provided with a curve in the horizontal plane. Depending on the curvature and the rigidity of the stored tube, it will be necessary in some cases to provide the carriers 10 with a lateral support where the guide track curves in the horizontal plane. This support may be in the form of slide surfaces or support wheels having a vertical axis 28 that is built into carriers 10. The slide surface or support wheel where necessary runs against a support surface 29; see Fig. 8b.

The guide track formed by angle beams 13, 14 may be supported in various ways, depending on space conditions, etc. on board the barge, and in Figs. 8, 9 and 10 three possible foundation means are shown: Fig. 8 shows use of side brackets 19 extending out from, for example, a deck housing 20, while Fig. 9 shows a suspension device whereby the track line is suspended in brackets 21 from below a deck 22, while Fig. 10 shows an arrangement where trestles 25 rise up from deck 23 and support the guide track 13, 1 .

As shown in Fig. 4 (and in Fig. 3), the guide track includes a storage section 9. This is produced by the bending of angle beams 13, 14 downward in the vertical plane to form a diagonal track line where carriers 10 may be lined up, as shown in Figs. 3 and 4. The individual carriers 10 are, as mentioned previously, connected together by means of a chain 11, so as to form a train or chain of carriers.

All the carriers 10 are identical, preferably with the exception of the first and last carrier which advantageously may be designed for a special fit onto the connector heads 5 formed on the ends of pipeline 3. In principle, however, all the carriers may be alike, as mentioned above, and may be constructed in a very simple manner, as shown In Figs. 5-6, where the carrier or cradle is made from a curved steel T beam, in this case covered with a rubber coating 26. Th running wheels 17 and 18 are fastened to the cradle ends i a suitable manner, by means of simple brackets or a housin screwed securely thereto.

Claims

P a t e n t C l a i m s

1.

An apparatus for feeding and storing a bendable, elongate body in extended, horizontal position, preferably a length of flexible pipeline (3) intended for fluid conduction, comprising a guide track having support means for the bendable elongate body, c h a r a c t e r i z e d i n that the support means are constructed as carriers (10) in the guide track (8), slidable in the longitudinal direction thereof, for bearing the bendable elongate body (3).

2.

An apparatus according to claim 1, c h a r a c t e r i z e d i n that the guide track includes a storage section (9), where the carriers (10) are stored when not in use, and a bearing section (8), where the carriers (10) are situated when in use and bearing said body (3).

3.

An apparatus according to claim 2, c h a r a c t e r i z e d i n that the storage section (9) is in the form of a diagonal section of track line extending downward from one end of the horizontal bearing section (8).

4.

An apparatus according to claim 3, c h a r a c t e r i z e d i n that the guide track is arranged with its horizontal bearing section (8) on level with a support path (4) for the body (3), with the sloping storage section (9) extending down under the support path (4).

5.

An apparatus according to one of the preceding claims, c h a r a c t e r i z e d i n that the carriers (10) are coupled together with a flexible, elongated drive member (11), for example a chain, running in the- longitudina direction of the body (3).

6.

An apparatus according to one of the preceding claims, c h a r a c t e r i z e d i n that each carrier (10) i formed as a cradle adapted to the circumferential shape o the elongate body (3), having running wheels (17,18) at eac end of the cradle for movement on/in the guide track (8,9,13,

14).

7.

An apparatus according to one of the preceding claims, c h a r a c t e r i z e d b y a winch (7) for hauling in/ feeding out the body (3), and an auxiliary winch (12) for initiating the discharge of the body.