NO344110B1

NO344110B1 - Element for mooring system

Info

Publication number: NO344110B1
Application number: NO20180256A
Authority: NO
Inventors: Geir Furberg
Original assignee: Aqualine As
Priority date: 2018-02-19
Filing date: 2018-02-19
Publication date: 2019-09-09

Description

Element for mooring system

The invention relates to an element for attaching three or more lines to each other, use of such an element in a mooring system for aquaculture systems, and a mooring system for floating structures.

Floating constructions to be held at a given location or position, are normally moored with lines from the construction to the sea-bed and/or to the shore if the construction is sufficiently close to the shore. The lines are moored to the sea-bed and/or shore in a convenient way according to prior art. Conditions such as wind, waves and tidal current will affect the constructions, and large forces from different directions will affect the lines holding the construction in place. Thus, it is very important that not only the lines but also the joints are sufficiently strong to resist such forces over time. Damage to the mooring system may result in breakdown of the net cage or plant, which will have environmental consequences in addition to material and financial loss to the owner of the plant.

In the following the invention will be described with reference to aquaculture systems for fish at sea, but it may also be used in fresh water and/or as mooring for floating rafts, offshore constructions and other floating constructions. An aquaculture system often comprises one or more net cages, an anti-bird net, equipment for holding the anti-bird net, and mooring systems for the net cages. An aquaculture system may also comprise one or more rafts. The expression "aquaculture system" is known to a person skilled of the art, and is thus not further defined here.

A traditional mooring system for an aquaculture system comprises a grid of mooring lines under water, and anchoring lines running from the grid to the mooring in the sea-bed or shore. The grid surrounds several net cages, preferably one net cage in each square of the grid. The mooring system also comprises lines from the grid to floating buoys and lines from the grid to the net cage. The different lines are connected to each other, usually by means of mooring plates being metal plates having thorough holes wherein the lines are fastened by eyelets and shackles. A lot of components of metal, preferably steel, are thus used in traditional mooring systems, and the weight of those components must be compensated by the floating capacity of the system, for instance the floating collar.

The connection between the different lines are essential for maintaining the stability of the plant, and must be embodied both to transfer and resist forces from all the lines, downward from the anchoring line(s), horizontally from the grid and the lines running to the fish cage, and upwards from the lines running to the fish cage and to the buoys. It is not unusual that 16 lines running in different directions, are connected in one such joint. Joints in prior art normally comprises a metal plate as said above, which results in wear and tear of the lines over time. The system must be regularly supervised and the worn parts must be replaced. Upon supervision, the mooring system must be raised to the surface, which is heavy and comprehensive work, but it is also dangerous when such heavy elements are raised and lowered.

It is known to use ropes as an alternative to steel in parts of a mooring system, wherein the ropes are tied to each other in knots. In the knots being used, the rope will be bent in steep angles through the knot, and the rupture strength will be reduced. In order to achieve sufficient rupture strength the rope must be oversized. NO 337394 and NO 339200, both being inventions from Aqualine AS, describe another type of knots for tying the lines of the mooring system to each other. The drawback of these knots is that the whole knot must be untied if one of the lines needs to be loosened or replaced.

WO 2012/154054 describes a joint in a mooring system for an aquaculture system as described above, as the coupling plate and the corresponding shackle and eyelet are replaced by a number of round slings. There are however, problems when parts of the mooring system must be replaced, as the round slings are tied so hard to each other that they must be cut to be released. During rough weather there is also a problem that the lines attached to the round sling, slide along the round sling, and thus that the formation of the mooring may become altered.

Object

The object of the present invention is to provide a mooring system without the problems described above. Another object is to provide a mooring system being lighter than traditional systems, and preferably without the need of external parts, especially without the need of metal parts. There is also an object to provide a mooring system having improved operating time, and wherein parts may be replaced in a simple and convenient way without the need for raising and possible replacing the whole system. Yet another object is that the mooring system should be operable even if maintenance and/or replacement of some components are made on the system. Finally, there is an object that the system should be reliable and give low risk for mistakes during installation.

The invention

The objects are met by an element for attaching three or more lines to each other, use of such an element in a mooring system, and a mooring system for floating structures comprising such an element, according to the characterizing part of the independent claims. Further advantageous features are stated in the dependent claims.

The present invention relates to an element for attaching three or more lines to each other, the lines extend in different directions relative to each other. The element comprises a cord provided as an endless ring, in the following referred to as a ringcord. If the cord is a lengthy element such as a rope, the ends may be fastened to each other to create a ring. The element further comprises a cord attached to the ring-cord and arranged to create three or more loops along the circumference of the ring-cord. This cord will in the following be referred to as loop-cord. The loops are distributed along the circumference of the ring-cord. A mantle surrounds the ringcord and at least parts of the loop-cord. The lines to be attached to each other are each attached to the ring-cord.

The wording "line", "cord" and "wire" as used in this application are synonyms, and may each and independently be a rope, strap, band, string, thread, cable or the similar which is suitable for the said purpose. Even an endless round sling may be used if suitable. A skilled person would know which type of line, cord or wire is suitable for the purpose in question, and suitable combinations of lines, cords and wires.

A "rope" as used in this application is twisted or braided of a number of strands. The strands may be of synthetic or natural fibres, such as hemp, manila, nylon, polypropylene or plastics. A preferred rope is a polyethylene rope, such as a Dyneema ® Rope, and more preferred it is braided of 8 strands.

The loop-cord is attached to the ring-cord and arranged in three or more loops protruding from the circumference of the ring-cord. The loops are distributed along the circumference of the ring-cord, and the loop-cord between the loops may be arranged parallel to, and along with, the ring-cord. The attachment to the ring-cord may be provided by the mantle which surrounds the ring-cord and at least parts of the loop-cord. In a preferred embodiment, the loop-cord is further attached to the ring-cord by twisting the loop-cord around the ring-cord before and after every loop. In an even more preferred embodiment, the loop-cord is attached to the ring-cord by twisting the loop-cord around the ring-cord, and tying a knot before and after each loop.

The lines to be attached to each other, are preferably attached to the ring-cord within a loop of the loop-cord. In an other embodiment the lines are attached to the ringcord between the loops of the loop-cord. In yet another embodiment, the lines are attached to the ring-cord both within and between the loops of the loop-cord.

By "the ring-cord within a loop of the loop-cord" it is herein meant the parts of the ring-cord where the loops are, that is from the site where the loop-cord is rising from the surface of the ring-cord, to the site where the loop-cord is entering the surface of the ring-cord again. By "the ring-cord between the loops of the loop-cord" it is herein meant the parts of the ring-cord wherein the loop-cord is running along with the ringcord.

The mantle is surrounding the ring-cord and at least parts of the loop-cord. The mantle should preferably not cover the loops of the loop-cord, but the parts of the loop-cord running along the circumference of the ring-cord, should however, be covered by the mantle. If the loop-cord is twisted or tied to the ring-cord, then the twist and/or tie should preferably also be covered by the mantle, in order to strengthen and protect the attachment of the loop-cord to the ring-cord. In another embodiment is a separate mantle covering the loops of the loop-cord.

The mantle may be any suitable mantle or tubing, for instance a heat-shrinkable tubing or a wire sleeve, such as a wowen wire sleeve. In a preferred embodiment, the mantle is braided by a number of filaments, onto the ring-cord. The number of filaments may vary in relation to the thickness of the cords and/or the width of each filament. The material of the filament depends on the environment where the element is to be used, which will be obvious to a person skilled of the art. In a more preferred embodiment, the mantle is braided of 12 filaments, and the filaments are made of polyester.

By braiding the mantle directly onto the cord(s) each filament of the mantle will be tightened around the cord(s), and the resulting mantled cord(s) will have an even and durable surface, preventing sand and/or foul from contacting the cord, and without reducing the strength or flexibility of the cord. Further, as the mantle encloses the cord so tight, the risk for foreign substances to unintentionally hook or fasten in the mantle is substantially reduced. Methods for braiding are known for instance from WO2003/054291 or WO2012/1343010.

The loops of the loop-cord should be distributed evenly on the ring-cord, and when the lines attached to the element are tensioned, the element will be triangular if three lines are attached, square if four lines are attached etc. At least parts of the loopcord are covered by the mantle, and thus the loops will not be displaced along the ring-cord. This effect will be enhanced when the loop-cord is twisted or twisted and tied to the ring-cord. As the lines are attached to the ring-cord within or between the loops of the loop-cord, the loops will prevent the lines from sliding along the ring, and the direction and position between the lines attached to the element will not be changed. In embodiments where the lines are parts of a mooring system, the formation of the system will thus be stable.

The element comprises three or more loops for attaching three or more lines to the ring-cord within the loop. However, more lines than loops may be attached to the element, either by attaching more than one line within each loop, or by attaching lines to the ring-cord between the loops. The lines may be fastened to the ring-cord within or between the loops in any convenient way, which will be obvious to a person skilled of the art.

The ring-cord is preferably a rope, more preferred a rope made of strands, preferably braided strands. In a preferred embodiment, the loop-cord is also a rope made of strands, preferably braided strands. When a rope should be used as an endless ring, such as the ring-cord, the ends of a rope are spliced, and the splicing is preferably secured by a seizing.

The ends of the loop-cord may preferably be connected to each other, such that the loop-cord also constitutes an endless ring. In an alternative embodiment, several loop-cords may be used to create the loops.

By using an element according to the present invention for attaching lines to each other, one achieves a safe and sufficiently strong attachment without needing to over dimensioning the lines and cords, and without external elements or materials which may cause tear and wear and possible rupture of a mooring system. A mooring system wherein the mooring lines are connected to each other by an element according to the present invention, is thus considerably lighter than traditional solutions comprising a mooring plate, but still equally safe and reliable.

The invention also relates to a mooring system comprising at least three lines extending in different directions, wherein each of the lines are attached or connected to each other by means of an element as described above. The lines are preferably are attached to the ring-cord of the element, within or between the loops of the loopcord.

The invention further relates to a mooring system for floating constructions such as aquaculture systems. A well known mooring system for aquaculture plants with several net cages, comprises a grid of mooring lines, the lines are running in at least two directions and create a grid with several squares. The grid is preferably submerged. Net cages are arranged within the grid, and preferably the grid is designed in such a way that each net cage is arranged in a different square, surrounded by the lines of the grid. The size of each square of the grid depends thus on the preferred size of the net cage. The number of squares, and thus the number of joints and mooring lines depends on the number of net cages. The mooring lines constituting the grid are connected to each other in the joints by means of an element as described above, in that each line is attached to the ring-rope between or within a loop of the loop-cord.

The mooring system further comprises anchoring lines from the grid to the sea-bed or shore, lines from the grid to floating elements, such as buoys, and cage lines from the grid to the net cages. These lines are also attached to the ring-cord of the element, either within or between a loop of the loop-cord.

In a preferred embodiment, a number of wires are attached to the ring-cord of the element, and protrudes to a common suspension point above the element, where the wires are attached to each other. A line to a floating element on the surface of the water may preferably be fastened to this suspension point.

A mooring system according to the present invention does not use a traditional mooring plate of steel as described above, and is thus substantially lighter. The work related to mounting and inspection of the mooring system will thus be easier and less dangerous. Upon mounting of a mooring system according to the present invention one may use only manpower, while mounting of traditional systems comprising a mooring plate, requires use of a crane due to the weight of the mooring plate. During inspections of the mooring system, a junction between the lines will often be lifted to the surface, and thus work related to inspections are also related to the weight of the system.

The lines to be used according to the present invention may be any line suitable for mooring of an aquaculture system, which will be obvious to a person skilled of the art. It is however, preferred to use ropes, more preferred braided rope, and most preferred tubular or round braided rope. Further, a mooring line may be assembled of many lines connected to each other, and the different lines may not necessarily be of the same type.

In the following the invention will be described by reference to mooring of an aquaculture system, but it may of course also be used in other areas, which will be obvious to a person skilled in the art.

Example

The invention will now be described with the help of the enclosed figures, showing an element and a mooring system according to the present invention. The different parts of the figure are not necessarily in scale to each other, as the figures are merely for illustrating the invention.

The following description of an exemplary embodiment refers to the figures, and the following detailed description is not meant or intended to limit the invention. Instead, the scope of the invention is defined by the appended claims.

Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

The invention will in the following be described with reference to the enclosed figures, where

Figure 1 shows an element according to the invention,

Figure 2, shows the element of in Figure 1, without the mantle,

Figure 3 shows a mooring system of an aquaculture system, according to the invention, and

Figure 4 shows a part of a mooring system of an aquaculture system, according to the invention.

Figure 1 and 2 show an element according to the invention. The element comprises a ring-cord made of a rope which is spliced to an endless ring-rope 1. A loop-cord 2 made of rope is attached to the ring-rope, and arranged in 8 loops 3 protruding from the circumference of the ring-rope 1. A mantle of several filaments 4 is braided onto the ring-rope 1. The parts of the loop-rope 2 being between the loops 3 are also covered by the mantle, while the loops 3 protruding from the ring-rope 1, are not.

In Figure 2 the element is shown without the mantle, and shows that the loop-rope 2 is arranged on one side of the ring-rope 1 running along the circumference of the ring-rope. Before and after each loop 3 the loop-rope 2 is twisted around the ringrope 1 to and tied to create a knot 5, and thereby attaching the loop-rope to the ringrope. The knot 5 will also ensure that the loop 3 is not extended or displaced, and the distribution of forces will improve.

When the mantle is braided onto the ring-rope, the parts of the loop-rope 2 running along the circumference of the ring-rope 1, between the loops 3, and the knots 5 will be covered by the mantle. Only the loops 3 will not be covered by the mantle as shown in Figure 1.

The element shown in Figures 1 and 2 may be part of a mooring system of an aquaculture system, as shown in Figure 3 and Figure 4. The shown mooring system comprises a grid of mooring lines 6 defining a number of squares, one fish cage 7 arranged in each square, anchoring lines 8 from the grid to the sea-bed or shore, cage lines 9 from the grid to the net cages 7, and wires from the grid to floating elements (not shown).

The mooring lines 6 of the grid are attached to each other by means of an element according to the invention, such as the element shown in Figure 1 and 2. In the embodiment shown in Figure 3 and 4, ends of mooring lines 6 of the grid and possibly anchoring lines 8 at the same joint, are attached to the same element, and so are cage lines 9 running from the grid to the fish cage 7.The lines are attached to the element for instance by means of a knot arranged around the ring-rope, within or between the loops 3.

In Figure 4 it is shown a part of a mooring system in detail, comprising an element as shown in Figure 1 and 2. Four moooring lines 6 of the grid are attached to the ringrope 1 within a loop 3 of the loop-rope 2, and three cage lines 9 are attached to the ring-rope 1, between loops 3 where mooring lines 6 are attached. Figure 4 only shows cage lines running to one cage, for clarity issues. When the element is arranged at a central joint of a mooring system cage lines may be attached to the ring-rope within every loop, and further lines may be attached between the loops.

The example above is given to illustrate the invention and should not be used to interpret the following claims limiting. The scope of the invention is not limited by the example give above, but the following claims. Modifications and amendments of the invention, being obvious to a person skilled of the art, should also be included in the scope of the invention.

Claims

Patent claims

1. Element for attaching three or more lines to each other, wherein the lines extend in different directions relative to each other, characterized in that the element comprises

- a ring-cord (1) provided as an endless ring,

- a loop-cord (2) attached to the ring-cord and arranged in three or more loops (3) protruding from and distributed along the circumference of the ring-cord (1), and - a mantle surrounding the ring-cord and at least parts of the loop-cord, and wherein each line is attached to the ring-cord.

2. Element according to claim 1, characterized in that the lines are attached to the ring-cord within a loop of the loop-cord.

3. Element according to claim 1 or 2, characterized in that the lines are attached to the ring-cord, between the loops of the loop-cord.

4. Element according to any one of claims 1 - 3, characterized in that the loop-cord (2) is attached to the ring-cord (1) by twisting the loop-cord around the ring-cord before and after each loop (3).

5. Element according to claim 4, characterized in that the loop-cord (2) is attached to the ring-cord (1) by twisting the loop-cord around the ring-cord, and tying a knot (5) before and after each loop (3).

6. Element according to any one of the preceding claims, characterized in that the ring-cord is a rope.

7. Element according to any one of the preceding claims, characterized in that the loop-cord is a rope.

8. Element according to any one of the preceding claims, characterized in that the mantle is made of several filaments (4) which is braided onto the ring-cord (1) and at least parts of the loop-cord (2).

9. A mooring system for floating structures comprising at the least three lines (6, 8, 9) extending in different directions, characterized in that each of the lines are attached to the ring-cord (1) of an element according to any one of claims 1-8.

10. A mooring system according to claim 9, characterized in that the lines (6, 8, 9) are attached to the ring-cord (1) within a loop (3) of the loop-cord.

11. A mooring system according to claim 9 or 10, characterized in that the lines (6, 8, 9) are attached to the ring-cord (1), between the loops (3) of the loop-cord.

12. Mooring system according to any one of claims 9-11, characterized in that mooring lines (6) are arranged as a grid under water, and that the lines (6) of the grid are attached to a an element according to any one of claims 1-8, preferably to the ring-cord (1) within a loop (3) of the loop-cord.

13. Mooring system according to any one of claims 9-12, characterized in that the mooring system further comprises

- anchoring lines (8) from the grid to the sea-bed or shore,

- wires from the grid to floating elements, and

- cage-lines (9) from the grid to net cages (7) arranged in the squares of the grid,

and in that all these lines are attached to an element according to any one of claims 1-8.

14. Use of an element according to claim 1, for mooring a floating construction.

15. Use according to claim 14, wherein the floating constructions is an aquaculture system.