NO347750B1 - A buoyancy and clamping assembly for use with a subsea line and a method for providing buoyancy to a subsea line - Google Patents
A buoyancy and clamping assembly for use with a subsea line and a method for providing buoyancy to a subsea line Download PDFInfo
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- NO347750B1 NO347750B1 NO20211570A NO20211570A NO347750B1 NO 347750 B1 NO347750 B1 NO 347750B1 NO 20211570 A NO20211570 A NO 20211570A NO 20211570 A NO20211570 A NO 20211570A NO 347750 B1 NO347750 B1 NO 347750B1
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- 238000000034 method Methods 0.000 title claims description 17
- 229910000831 Steel Inorganic materials 0.000 claims description 10
- 239000010959 steel Substances 0.000 claims description 10
- 239000004033 plastic Substances 0.000 claims description 5
- 229920003023 plastic Polymers 0.000 claims description 5
- 229920000271 Kevlar® Polymers 0.000 claims description 4
- 239000004761 kevlar Substances 0.000 claims description 4
- 229920000642 polymer Polymers 0.000 claims description 3
- 230000008901 benefit Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
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- 238000005516 engineering process Methods 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
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- 238000001816 cooling Methods 0.000 description 1
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- 235000012489 doughnuts Nutrition 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
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- 238000007689 inspection Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B22/00—Buoys
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L1/00—Laying or reclaiming pipes; Repairing or joining pipes on or under water
- F16L1/12—Laying or reclaiming pipes on or under water
- F16L1/20—Accessories therefor, e.g. floats, weights
- F16L1/24—Floats; Weights
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/01—Risers
- E21B17/012—Risers with buoyancy elements
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/01—Risers
- E21B17/015—Non-vertical risers, e.g. articulated or catenary-type
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- General Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
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- Other Liquid Machine Or Engine Such As Wave Power Use (AREA)
- Earth Drilling (AREA)
Description
A BUOYANCY AND CLAMPING ASSEMBLY FOR USE WITH A SUBSEA LINE AND A METHOD
FOR PROVIDING BUOYANCY TO A SUBSEA LINE
Technical field
The present disclosure relates to a buoyancy and clamping assembly for use with a subsea line and a method for providing buoyancy to a subsea line. More specifically, the disclosure relates to a buoyancy and clamping assembly for use with a subsea line and a method for providing buoyancy to a subsea line as defined in the introductory parts of claim 1 and claim 10.
Background art
The industry standard for distributed float elements usually comprises internal clamps (typically epoxy or metal) to facilitate a flexible grip around a flexible riser or umbilical, wherein two half-shell floats that provide buoyancy usually rotoformed PE or GRP filled with syntactic foam (to withstand deep water) and a series of outer bands to hold the buoyancy shells on the clamp (usually Kevlar).
A problem with the solutions of the prior art is that they are too expensive to produce and also too time consuming and expensive to mount. Once mounted it is almost impossible or difficult/expensive to substitute a defect floating element.
A further problem with such prior art assembles is that the clamps is hidden once the buoyancy shell is arranged around it, and thereby hiding the clamp for any visual inspection. A further problem is that the clamp is adapted to a single buoyancy shell buoyancy forces.
There is thus a need for an improved type of distributed float element, and the way they are arranged on a subsea line.
Summary
It is an object of the present disclosure to mitigate, alleviate or eliminate one or more of the above-identified deficiencies and disadvantages in the prior art and solve at least the above mentioned problem. Present disclosure further describes an assembly and method which provides standard, or close to standard, buoyancy requirements for various subsea lines, such as 66 kV dynamic cables. Further, specifically for power cables the solution may improve the task of avoiding hot spots on the cable.
According to a first aspect there is provided a buoyancy and clamping assembly for use with a subsea line, comprising:
- one or more buoyancy elements,
- one or more clamping elements, wherein the one or more clamping elements are fastened to a subsea line, and
- one or more set of fastening elements, wherein a first set of fastening elements are in a first end connected to, or being part of, a clamp connecting member of a first clamping element, and in a second end connected to, or being part of, a connecting member of a first buoyancy element, such that the first buoyancy element being restricted to move further than a maximum length from the clamping element defined by the length of the first set of fastening elements.
Thus, by arranging a clamp at a desired point of the subsea line, the position of the buoyancy element is defined by the clamping element and the size of the fastening elements.
According to some embodiments, the clamping element is fastened to the subsea line by clamping element fastening means, and the clamping element is arranged outside, or partly outside, the buoyancy element, such that the clamp connecting member of the clamping element can accessed without removing the associated buoyancy elements.
It is thereby possible to access clamping element and buoyancy element individually without having to dismount or damage the other.
According to some embodiments, the subsea line is one of, but not limited to, a subsea: cable, hose, umbilical, rope or flexible riser.
The buoyancy and clamping assembly of present disclosure is typically employed by subsea and offshore operations such as offshore windmill plants and offshore drilling and explorations, and specifically for subsea lines for electric power, oil and gas, water, pressurized air and other.
According to some embodiments, the buoyancy and clamping assembly comprises: - one or more further buoyancy element, and
- a set of intermediate fastening elements arranged to connect any two buoyancy elements, wherein the set of intermediate fastening elements are in a first end connected to the earlier buoyancy element, and in a second end connected to the later buoyancy element.
Thus, any number of buoyancy elements may be cooperating to create required buoyancy and required catenary to a subsea line. All buoyancy elements having a defined distance apart, and connected to the subsea line by one or more clamping elements.
According to some embodiments, the buoyancy and clamping assembly comprises: - a second clamping element, and
- a last set of fastening elements, wherein the second clamping element is arranged on a far side of all of the one or more buoyancy elements arranged between the first and second clamping element, and the last set of fastening elements are in a first end connected to the second clamping element, and in a second end connected to the last buoyancy element, such that the last buoyancy element being restricted to move further than a maximum length from the clamping element defined by the length of the last set of fastening elements.
Thus, it is ensured that no buoyancy elements may cluster up with other buoyancy elements, and a smooth catenary of the subsea line is ensured along the length of the set of buoyancy elements.
According to some embodiments, the buoyancy and clamping assembly comprises: - one or more intermediate clamping elements, and
- for each intermediate clamping element a first and second set of intermediate fastening elements, wherein the first set of intermediate fastening elements are in a first end connected to the intermediate clamping element, and in a second end connected to the earlier buoyancy element, such that the earlier buoyancy element being restricted to move further than a maximum length from the intermediate clamping element defined by the length of the first set of intermediate fastening elements, and
- the second set of intermediate fastening elements are in a first end connected to the intermediate clamping element, and in a second end connected to the next buoyancy element, such that the next buoyancy element being restricted to move further than a maximum length from the intermediate clamping element defined by the length of the second set of intermediate fastening elements, and a smooth curved catenary form of the subsea line may be further improved.
According to some embodiments the first, second, and intermediate clamping elements may be made of, but not limited to, steel and/or plastic.
According to some embodiments the first, second and intermediate fastening elements are structural members that may be made of one of or combination of, but not limited to: Kevlar, steel, and Polymer.
According to some embodiments the clamping elements comprise: a first or second set of connecting means for connecting the first or second set of fastening elements, or a first and second set of connecting means for connecting the first and second set of intermediate fastening elements respectively.
Various configurations of the clamping element fulfill fastening requirements in accordance to its position in a chain of buoyancy element.
According to a second aspect there is provided a method for providing buoyancy to a subsea line comprising the following steps:
- providing a buoyancy and clamping assembly according to the above described aspects, and
- providing a subsea line.
According to some embodiments, the method further comprises the steps:
- fastening the clamping elements to the subsea line,
- connecting the fastening elements to the clamping element,
- arranging the buoyancy elements on the subsea line adjacent the clamping element, and
- connecting the fastening elements to the buoyancy elements.
Effects and features of the second aspect are to a large extent analogous to those described above in connection with the first aspect. Embodiments mentioned in relation to the first aspect are largely compatible with the second aspect.
The present disclosure will become apparent from the detailed description given below. The detailed description and specific examples disclose preferred embodiments of the disclosure by way of illustration only. Those skilled in the art understand from guidance in the detailed description that changes and modifications may be made within the scope of the disclosure.
Hence, it is to be understood that the herein disclosed disclosure is not limited to the particular component parts of the device described or steps of the methods described since such device and method may vary. It is also to be understood that the terminology used herein is for purpose of describing particular embodiments only, and is not intended to be limiting. It should be noted that, as used in the specification and the appended claim, the articles "a", "an", "the", and "said" are intended to mean that there are one or more of the elements unless the context explicitly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, and the like. Furthermore, the words "comprising", "including", "containing" and similar wordings does not exclude other elements or steps.
Terminology
The term "subsea line " is to be interpreted as any flexible cable, hose, umbilical, rope or riser, intended for use in subsea operations. This include but is not limited to power cables, mooring lines, oil and gas pipes, and others.
The term " fastening elements " is to be interpreted as linear structural member or a tie, strap, tie rod, eyebar, guy-wire, suspension cables, or wire ropes, are examples of linear structural components designed to resist tension. Ties may be made of any tension resisting material.
The term " steel " is to be interpreted as any type of alloy and mixtures of metallurgical phases, including duplex steel.
Brief descriptions of the drawings
The above objects, as well as additional objects, features and advantages of the present disclosure, will be more fully appreciated by reference to the following illustrative and non-limiting detailed description of example embodiments of the present disclosure, when taken in conjunction with the accompanying drawings.
Figure 1A shows a side view of an open distributed float elements comprising and internal clamps
Figure 1B shows a diagram of a flexible subsea line aided by a set of distributed float elements to provide a desired subsea line catenary arch.
Figure 2A shows a clamping element and two buoyancy elements arranged according to an embodiment of the present disclosure.
Figure 2B shows a first and last clamping element and intermediate buoyancy elements according to an embodiment of present disclosure.
Figure 3 shows an intermediate clamping element and two buoyancy elements arranged according to an embodiment of the present disclosure.
Figure 4 show a detailed view of an embodiment of a first or last clamping element according to an embodiment of present disclosure.
Figure 5 shows a detailed view of an embodiment of an intermediate clamping element according to an embodiment of present disclosure.
Figure 6 shows an embodiment of the use of the clamping elements and buoyancy elements for aiding the buoyancy of a subsea line according to an embodiment of present disclosure.
Figure 7 illustrate typical desired subsea line catenaries.
Detailed description
The present disclosure will now be described with reference to the accompanying drawings, in which preferred example embodiments of the disclosure are shown. The disclosure may, however, be embodied in other forms and should not be construed as limited to the herein disclosed embodiments. The disclosed embodiments are provided to fully convey the scope of the disclosure to the skilled person.
Many of the embodiments discussed is exemplified by maintaining umbilical power cable for power transmission from offshore windmills, but the present disclosure could be applied to any subsea line wherein additional buoyancy is required.
Figure 2A shows a first aspect of this disclosure, and shows a buoyancy and clamping assembly for use with a subsea line, comprising:
- one or more buoyancy elements 2,2’,2’’,
- one or more clamping elements 1,5,10, wherein the one or more clamping elements 1,5 are fastened to a subsea line 4, and
- one or more set of fastening elements 3,3’,3’’, wherein a first set of fastening elements 3 are in a first end connected to, or being part of, a clamp connecting member 6,6’ of a first clamping element 1, and in a second end connected to, or being part of, a connecting member 9,9’ of a first buoyancy element 2, such that the first buoyancy element 2 being restricted to move further than a maximum length L from the clamping element 1 defined by the length of the first set of fastening elements 3.
The clamping elements 1,5,10 may thus be arranged external to the buoyancy elements 2,2’,2’’, and the externally arranged clamping elements 1,5,10 are one of the key elements of the present disclosure, as this facilitates easy mounting and replacement of both clamping elements 1,5,10, but also of buoyancy elements 2,2’,2’’ if substitution is required. It may even be possible to facilitate for In-situ replacements. The clamping elements 1,5,10 are facilitated with a grip strong enough to grip to hold buoyancy and the weight of the subsea line (4). Further it is easy to add clamping forces simply by adding more clamping elements 1,5,10, or substitute clamping elements 1,5,10 with larger/smaller size/characteristics.
One obvious benefit is that it is possible to mount many in a short time, and it is possible to see the clamp facilitating for easy inspection and status verification. It is also easy to adjust the clamping elements 1,5,10 characteristics to suit a change in required holding strength.
Thus, by arranging a clamp at a desired point of the subsea line, the position of the buoyancy element is defined by the clamping element and the size of the fastening elements.
It is thereby possible to access clamping element and buoyancy element individually without having to dismount or damage the other.
The connecting member 9 of the buoyancy elements 2,2’,2’’ may be provided inside the buoyancy elements 2,2’,2’’ as illustrated in figure 2A. However there may be a need to attach the fastening elements 3, 3’, 3’’ to a in situ installed buoyancy elements 2,2’,2’’, and thus it may be necessary to provide the buoyancy elements 2,2’,2’’ with outside connecting member 9’ as illustrated in figure 2B.
Typically the buoyancy elements 2,2’,2’’ of present disclosure is provided as a linked 2 half cylinder buoyancy elements having a recess 11 adapted to the subsea line 4 that the buoyancy elements 2,2’,2’’ are being mounted to. The two half cylinder buoyancy elements is arranged around the subsea line, and fastened to each other by encircling banding. Then the fastening elements 3, 3’, 3’’ is connected to the buoyancy elements 2,2’,2’’ in one end, and to adjacent buoyancy elements 2,2’,2’’ or clamping elements 1,5,10. It is no requirement to the recess 11 in the buoyancy elements to be an exact fit to the outer diameter of the subsea line 4, as the buoyancy elements 2,2’,2’’ may freely slide along the subsea line within the boundaries defined by the length L, l of the fastening elements 3, 3’, 3’’.
The ‘Donut’ Buoys thereby have no clamps, but are connected together using for example simple synthetic slings, and being secured by intermediate and end clamping elements 1,5,10.
The benefits of such an installation is that it uses proven technology of low cost components, wherein the buoyancy can accept a wide range of cable sizes, and clamping reduced by up to 1/25 of prior art. It is further huge reduction in installation time on board vessel.
Further advantages may comprise: Simple tether clamps, proven technology, can be steel or plastic, better cooling (avoiding number of hotspots), and far easier to inspect compared with prior art buoyancy elements.
To show one, non-limiting, example of an embodiment of present disclosure the following characteristics may be used:
The detailed characteristics of the clamping element 1, 5, 10 may be provided with clamp length of 500mm or larger. This may provide 5Te @ 2MPa clamping pressure. Thus, with DAF=2, SWL ~ 2.5Te per clamp, and 25 buoys, of buoyancy of 100kg, may be held with 1 clamp.
In one embodiment the fastening elements 3, 3’, 3’’ used may be Dyneema SK-78 Ø20mm having a breaking strength: ~300kN, and SWL ~ 5Te @ SF=6
Here the following abbreviations are used:
• DAF – Dynamic Amplification Factor
• SWL – Safe Working load
• Te – Metric TON
• MPa – Mega Pascal
• SF – Safety Factor
The example illustrates that 25 buoys can be held with 1 clamp, and compared with the example of prior art in figure 1 the saving of 24 clamping arrangements may be achieved.
Huge benefits related to cost, material use, work and maintenance resources may be achieved by using the techniques of present disclosure.
The disclosed techniques of present disclosure is not limited to the examples given above, and any combination of number of buoys, buoyancy, and material shall be covered. One typical variation is to use a clamp in both ends of a string of buoys. Thus, a saving of number of clamps of (number of buoys – 2).
The clamping element 1,5,10 may be fastened to the subsea line 4 by clamping element fastening means 7, and the clamping element 1,5,10 is arranged outside, or partly outside, the buoyancy element 1,5, such that the clamp connecting member 6,6’ of the clamping element 1,5,10 can accessed without removing the associated buoyancy elements 2,2’,2’’.
It is within the conceptual definition according to present disclosure to provide a clamping element 1,5,10 that is partly encapsulated by a buoyancy elements 2,2’,2’’, for example by a recess provided in the buoyancy element at the point of entry of the subsea line 4, the clamping element 1,5,10 may then be connected to the buoyancy element by a short clamp connecting member 6, 6’, 13, 13’ such as a Carabine hook or the like directly to a connecting member 9, 9’ of the buoyancy elements 2,2’,2’’. For such a partly embedded/hidden clamping element 1,5,10 the clamping element fastening means 7 may be arranged outside the recess provided in the buoyancy element such that it is easily accessed at all times.
Buoyancy modules tend to lose buoyancy over time, and wave configurations are in prior art inherently designed to accommodate up to a 10% loss of buoyancy. The easy access to the clamping elements allows an easy replacement of buoyancy elements, and the buoyancy elements does not need to be oversized to account for decaying buoyancy over time. When periodic service is facilitated the buoyancy element of present disclosure may easily be replaced if defect or too low buoyancy is detected.
The subsea line 4 may be one of, but not limited to a subsea: cable, hose, umbilical, rope or flexible riser. The concept of providing a better accessible, cheaper and faster to install buoyancy to any subsea entity may have many applications, and although buoyancy of a subsea line is used as example in present disclosure, it is within the concept of present disclosure to also encompass embodiments wherein the buoyancy and clamping assembly according to present disclosure is used in other subsea buoyancy tasks.
In an embodiment of the buoyancy and clamping assembly it further comprises:
- one or more further buoyancy element 2’, and
- a set of intermediate fastening elements 3’ arranged to connect any two buoyancy elements 2,2’, wherein the set of intermediate fastening elements 3’ are in a first end connected to the earlier buoyancy element 2,2’, and in a second end connected to the later buoyancy element 2’,2’’.
A plurality of buoyancy elements 2,2’ may be stringed together making up a long string of buoyancy elements separated by intermediate fastening elements 13,13’, and the string of buoyancy elements may be fastened to only one clamping element 1, 5 at one end of the string. Such an embodiment may require a controlled submerging operation of the line the buoyancy elements is arranged on, to avoid buoyancy elements 2,2’ to shift and move together when being submerged. It should be ensured that buoyancy forces stretches the intermediate fastening elements 13,13’ linking the buoyancy elements 2,2’ once the assembly being submerged. If it is a risk that the orientation of the line in such an embodiment will change and the clamping elements ends up at a higher position than the buoyancy elements, with the result that the buoyancy elements will be moved together by the buoyancy forces, it may be advantageous to arrange at least one clamping element at both ends of the string of buoyancy elements, to ensure that they are stretched apart independent of line orientation.
In an even further embodiment the buoyancy and clamping assembly comprises:
- a second clamping element 5, and
- a last set of fastening elements 3’’, wherein the second clamping element 5 is arranged on a far side of all of the one or more buoyancy elements 2,2’,2’’ arranged between the first and second clamping element 1,5, and the last set of fastening elements 3’’ are in a first end connected to the second clamping element 5, and in a second end connected to the last buoyancy element 2’’, such that the last buoyancy element 2’’ being restricted to move further than a maximum length from the clamping element defined by the length L’ of the last set of fastening elements 3’’.
Using at least one clamping element 1, 5 in each end of a plurality of stringed together buoyancy elements 2,2’ ensures that no buoyancy elements 2,2’ will be clustering together and ruin the distributed buoyancy forces of the assembly. The characteristics of the clamping elements 1, 5 must be configured to hold the buoyancy forces of the combined buoyancy elements 2,2’ being associated with the clamping element 1, 5.
It is in one embodiment a request to limit the length of the fastening elements 3,3’,3’’to avoid twist. In one embodiment the fastening elements 3,3’,3’’ may in fact be provided by a clip-on device, such as a Safety Carabine hook type clip. In other embodiments the fastening elements 3,3’,3’’ is comprised of a steel/plastic rod, providing rigidity mitigating twisting and/or securing the distance to be maintained, and the length of the fastening elements may be provided with longer lengths L, L’, l, l’.
The length L, L’, l, l’ between buoyancy elements/fastening elements depends on many factors. A string of buoyancy elements may be tuned against a set required buoyancy specifications dependent on the subsea line used, desired catenary of the subsea line and project it is used for. Twisting may effect the setup required for the project and may be mitigated by stiff fastening elements 3,3’,3’’ and/or adding more clamping elements 1,5, 10.
One alternative use for the concept according to present disclosure is to apply it to be used on moorings to lift it from sediment or to get a lifting access.
In a further embodiment the buoyancy and clamping assembly comprises:
- one or more intermediate clamping elements 10, and
- for each intermediate clamping element 10 a first and second set of intermediate fastening elements 13,13’, wherein the first set of intermediate fastening elements 13 are in a first end connected to the intermediate clamping element 10, and in a second end connected to the earlier buoyancy element 2’, such that the earlier buoyancy element 2’ being restricted to move further than a maximum length from the intermediate clamping element 10 defined by the length l of the first set of intermediate fastening elements 13, and
- the second set of intermediate fastening elements 13’ are in a first end connected to the intermediate clamping element 10, and in a second end connected to the next buoyancy element 2’’, such that the next buoyancy element 2’’ being restricted to move further than a maximum length from the intermediate clamping element defined by the length l’ of the second set of intermediate fastening elements 13’.
Thus any catenary may be achieved by easy and quick mounting process. When using first and last clamping devices and intermediate claiming elements there is no risk of the buoyancy elements clustering to one end of the string and any catenary of the subsea line may be configured.
Figure 7 shows the following configurations: a) Free hanging Catenary, b) Lazy wave, c) Steep wave, d) Lazy-S, e) Steep-S, and f) Pliant wave. Any other configuration may also be provided.
Figure 6 illustrates how the buoyancy and clamping assembly of present disclosure is used to facilitate a lazy wave embodiment to a subsea line 4. The scenario of figure 6 is an example where a120 mm cable has a required buoyance of approximately 40 Te, and this is solved by a 60 m string of approximately 40 pcs of 100kg buoys.
The configuration requirement is adapted to a number of factors such as water depth, hang-off location/vessel, subsea lines and mooring layout, and environmental data and the hang-off location/vessel motion characteristics.
In one embodiment of use the buoyancy and clamping assembly of present disclosure is used to eliminate the danger of hotspot locations in power cables when providing power cables to connect an offshore windmill(s) to the onshore electrical grid.
The first, second and intermediate clamping elements 1,5,10 may be made of one of, but not limited to: steel and/or plastic.
The first, second or intermediate fastening elements 3,3’,3’’,13,13’ are structural members may be made of, but not limited to, one of or combination of: Kevlar, steel, and Polymer.
The clamping elements 1,5,10 may comprise: a first or second set of connecting means 6,6’ for connecting the first or second set of fastening elements 3,3’,3’’, or a first and second set of connecting means 6,6’ for connecting the first and second set of intermediate fastening elements 13,13’ respectively.
Depending on the clamping element 1, 5, 10 configuration there is provided connecting means 6, 6’to facilitate a quick mounting/dismounting routine for the fastening elements 3, 3’, 3’’, 13, 13’. One example would be a safety click on/off clip.
In the event where buoyancy requirements of a line requires multiple buoyancy elements to be arranged back to back, with no separating space between each buoyancy element, it may be possible to arrange two clamping elements 1, 5, one at each end of the multiple buoyancy elements, such that only the two end buoyancy elements are directly connected to a clamping element 1, 5. Since all clamping elements are arranged back to back, no fastening elements 3,3’,3’’, 13, 13’ need to be utilized. In such an embodiment it could be envisaged to use a modified clamping element where the connecting means are substituted by a stopper flange arranged on the clamping element being arrange to press towards the outside of the outermost buoyancy elements.
The second aspect of this disclosure shows a method for providing buoyancy to a subsea line comprising the following steps:
- providing a buoyancy and clamping assembly according to any of the first, and - providing a subsea line 4.
The method further comprises the steps:
- fastening the clamping elements 1,5,10 to the subsea line 4,
- connecting the fastening elements 3,3’,3’’ to the clamping element,
- arranging the buoyancy elements 2,2’,2’’ on the subsea line 4 adjacent the clamping element 1,5,10, and
- connecting the fastening elements 3,3’,3’’ to the buoyancy elements 2,2’,2’’.
The person skilled in the art realizes that the present disclosure is not limited to the preferred embodiments described above. The person skilled in the art further realizes that modifications and variations are possible within the scope of the appended claims.
Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed disclosure, from a study of the drawings, the disclosure, and the appended claims.
Claims (12)
1. A buoyancy and clamping assembly for use with a subsea line, comprising:
- one or more buoyancy elements (2, 2’, 2’’),
- one or more clamping elements (1, 5, 10), wherein the one or more clamping elements (1, 5) are fastened to a subsea line (4), and
- one or more set of fastening elements (3, 3’, 3’’),
the buoyancy and clamping assembly being c h a r a c t e r i z e d b y :
- the buoyancy element (2, 2’, 2’’) having a recess (11) adapted to embrace the subsea line (4) and formed to allow buoyancy elements (2,2’,2’’) to freely move around the subsea line (4), and
- a first set of fastening elements (3) are in a first end connected to, or being part of, a clamp connecting member (6, 6’) of a first clamping element (1), and in a second end connected to, or being part of, a connecting member (9, 9’) of a first buoyancy element (2), such that the first buoyancy element (2) being restricted to move further along the subsea line than a maximum length (L) from the clamping element (1) defined by the length of the first set of fastening elements (3).
2. The buoyancy and clamping assembly according to claim 1, wherein
the clamping element (1, 5, 10) is fastened to the subsea line (4) by clamping element fastening means (7), and
the clamping element (1, 5, 10) is arranged outside, or partly outside, the buoyancy element (1, 5), such that the clamp connecting member (6, 6’) of the clamping element (1, 5, 10) can be accessed without removing the associated buoyancy elements (2, 2’, 2’’).
3. The buoyancy and clamping assembly according to claim 1 or 2, wherein the subsea line (4) is one of a subsea: cable, hose, umbilical, rope or flexible riser.
4. The buoyancy and clamping assembly according to any of the previous claims, further comprising:
- one or more further buoyancy element (2’), and
- a set of intermediate fastening elements (3’) arranged to connect any two buoyancy elements (2, 2’), wherein
the set of intermediate fastening elements (3’) are in a first end connected to the earlier buoyancy element (2, 2’), and in a second end connected to the later buoyancy element (2’, 2’’).
5. The buoyancy and clamping assembly according to any of the previous claims, further comprising:
- a second clamping element (5), and
- a last set of fastening elements (3’’), wherein the second clamping element (5) is arranged on a far side of all of the one or more buoyancy elements (2, 2’, 2’’) arranged between the first and second clamping element (1, 5), and the last set of fastening elements (3’’) are in a first end connected to the second clamping element (5), and in a second end connected to the last buoyancy element (2’’), such that the last buoyancy element (2’’) being restricted to move further than a maximum length from the clamping element defined by the length (L’) of the last set of fastening elements (3’’).
6. The buoyancy and clamping assembly according to any of the previous claims, further comprising:
- one or more intermediate clamping elements (10), and
- for each intermediate clamping element (10) a first and second set of intermediate fastening elements (13, 13’), wherein the first set of intermediate fastening elements (13) are in a first end connected to the intermediate clamping element (10), and in a second end connected to the earlier buoyancy element (2’), such that the earlier buoyancy element (2’) being restricted to move further than a maximum length from the intermediate clamping element (10) defined by the length (l) of the first set of intermediate fastening elements (13), and
- the second set of intermediate fastening elements (13’) are in a first end connected to the intermediate clamping element (10), and in a second end connected to the next buoyancy element (2’’), such that the next buoyancy element (2’’) being restricted to move further than a maximum length from the intermediate clamping element defined by the length (l’) of the second set of intermediate fastening elements (13’).
7. The buoyancy and clamping assembly device according to any of the previous claims, wherein:
the first, second, and intermediate clamping elements (1,5,10) are made of steel and/or plastic.
8. The buoyancy and clamping assembly device according to any of the previous claims, wherein:
first, second, and intermediate fastening elements (3, 3’, 3’’, 13, 13’) are structural members made of one of or combination of: Kevlar, steel, and Polymer.
9. The buoyancy and clamping assembly according to any of the previous claims, wherein: the clamping elements (1,5,10) comprise:
a first or second set of connecting means (6, 6’) for connecting the first or second set of fastening elements ((3, 3’, 3’’).
10. The buoyancy and clamping assembly according to any of the previous claims 1 to 8, wherein:
the clamping elements (1,5,10) comprise:
a first and second set of connecting means (6, 6’) for connecting the first and second set of intermediate fastening elements (13, 13’) respectively.
11. A method for providing buoyancy to a subsea line being
c h a r a c t e r i z e d b y comprising the following steps:
- providing a buoyancy and clamping assembly according to any of claim 1 to 10, and - providing a subsea line (4).
12. The method according to claim 11, the method further comprising the steps:
- fastening the clamping elements (1, 5, 10) to the subsea line (4),
- connecting the fastening elements (3, 3’, 3’’) to the clamping element,
- arranging the buoyancy elements (2, 2’, 2’’) on the subsea line (4) adjacent the clamping element (1, 5, 10), and
- connecting the fastening elements (3, 3’, 3’’) to the buoyancy elements (2, 2’, 2’’).
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NO20211570A NO347750B1 (en) | 2021-12-22 | 2021-12-22 | A buoyancy and clamping assembly for use with a subsea line and a method for providing buoyancy to a subsea line |
| PCT/NO2022/050323 WO2023121478A1 (en) | 2021-12-22 | 2022-12-20 | A buoyancy and clamping assembly for use with a subsea line and a method for providing buoyancy to a subsea line |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NO20211570A NO347750B1 (en) | 2021-12-22 | 2021-12-22 | A buoyancy and clamping assembly for use with a subsea line and a method for providing buoyancy to a subsea line |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| NO20211570A1 NO20211570A1 (en) | 2023-06-23 |
| NO347750B1 true NO347750B1 (en) | 2024-03-18 |
Family
ID=86903259
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO20211570A NO347750B1 (en) | 2021-12-22 | 2021-12-22 | A buoyancy and clamping assembly for use with a subsea line and a method for providing buoyancy to a subsea line |
Country Status (2)
| Country | Link |
|---|---|
| NO (1) | NO347750B1 (en) |
| WO (1) | WO2023121478A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2626354A (en) * | 2023-01-19 | 2024-07-24 | Advanced Innergy Ltd | Buoyancy module |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4107802A (en) * | 1976-05-25 | 1978-08-22 | Compagnie Generale Pour Les Developpements Operationnels Des Richesses Sous-Marines "C. G. Doris" | Apparatus for releasing submerged floats |
| WO2021176205A1 (en) * | 2020-03-04 | 2021-09-10 | Balmoral Comtec Limited | Subsea line clamp assembly |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2309576B (en) * | 1996-01-26 | 2000-03-08 | Crp Group Ltd | Buoyancy device |
| NO304082B1 (en) * | 1996-12-16 | 1998-10-19 | Abb Offshore Technology As | A buoyancy device |
| US9033614B2 (en) * | 2013-05-29 | 2015-05-19 | Ge Oil & Gas Uk Limited | Pipe components and methods of manufacture |
| US10184589B2 (en) * | 2015-03-04 | 2019-01-22 | Ge Oil & Gas Uk Limited | Riser assembly and method |
| DK201670301A1 (en) * | 2016-05-09 | 2017-12-04 | Subcpartner As | A buoyancy module, a clamp for the buoyancy module, and a method of mounting the buoyancy module onto an underwater pipe |
| GB2551816B (en) * | 2016-06-30 | 2019-04-03 | Trelleborg Offshore Uk Ltd | Stacked buoyancy module for a subsea member |
-
2021
- 2021-12-22 NO NO20211570A patent/NO347750B1/en unknown
-
2022
- 2022-12-20 WO PCT/NO2022/050323 patent/WO2023121478A1/en active Application Filing
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4107802A (en) * | 1976-05-25 | 1978-08-22 | Compagnie Generale Pour Les Developpements Operationnels Des Richesses Sous-Marines "C. G. Doris" | Apparatus for releasing submerged floats |
| WO2021176205A1 (en) * | 2020-03-04 | 2021-09-10 | Balmoral Comtec Limited | Subsea line clamp assembly |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2023121478A1 (en) | 2023-06-29 |
| NO20211570A1 (en) | 2023-06-23 |
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