Detachable mooring chain link, connection system and method for disconnecting two mooring chains underwater

Abstract

The detachable mooring link (100) has an imaginary transverse plane passing through the center of the detachable link (100) dividing the detachable link into an upper portion for connecting an upper chain (200a) and a lower portion for connecting a lower chain (200b), and the body (110) has an upper arched section (110a), a lower arched section (110b) and a straight section (110c) to which the arched sections (110a, 110b) are attached, the body (110) has an opening (111) closed between the arch segments (110a, 110b) with a closure (120) and has a connection point (112) receiving a lifting force (Lf) that swings the detachable link (100) towards the opening (111) to release the upper mooring chain (200a) from the upper arch segment (110a) through the opening (111), where the connection point (112) is arranged in an upper portion of the detachable link (100) located above an imaginary transverse plane.

Description

Technical Field

[0001] The present invention relates to a detachable mooring link for connecting and disconnecting two mooring chains underwater. Background Art

[0002] Floating structures such as drilling vessels or offshore platforms need to be anchored to the seabed in order not to be subject to displacements that may be caused by currents or weather conditions. Anchoring devices fixed to the seabed and mooring chains attaching the floating structure to the anchoring devices are used to moor the floating structure.

[0003] Detachable mooring links for connecting and disconnecting mooring chains are known. The detachable link has the shape of a conventional link, i.e. a ring-shaped configuration, but it can be opened to enable the connection of the end links of two mooring chains and, when closed, connects the two links and the detachable link is arranged between the two mooring chains like another link.

[0004] For example, ES2168884 A1, which belongs to the same applicant as the present invention, shows a detachable mooring link, which includes a generally C-shaped link body having an upper arched segment for connecting an upper mooring chain, a lower arched segment for connecting a lower mooring chain, and a straight segment to which the two arched segments are attached. The link body has an opening between the two arched segments that can be closed with a closure. In order to connect the upper mooring chain and the lower mooring chain, the end link of each chain is introduced through the opening of the link body, and the opening is closed with a closure, and the end link of each mooring chain is attached by a detachable link.

[0005] WO2020173925 A1 shows another detachable mooring link, which has an upper portion for connecting an upper mooring chain and a lower portion for connecting a lower mooring chain. The detachable mooring link includes a generally C-shaped link body, which has an upper arched segment for connecting an upper mooring chain, a lower arched segment for connecting a lower mooring chain, and a straight segment to which the arched segment is attached. There is an opening closed by a closure between the free ends of the two arched segments. The closure is linear, similar to the shape of the straight segment, one end of which is rotatably connected to the free end of the lower arched segment, and the other end of which can be connected and disconnected with the free end of the upper arched segment for opening and closing the opening. In addition, the link has a transverse member, which is arranged between the straight segment of the link body and the free end of the lower arched segment in an inclined orientation. The transverse member is used to connect a sling that generates a lifting force on the link. The force causes the link to swing toward the opening to release the upper mooring chain from the upper arched segment of the link body through the opening.

[0006] In this way, when a lifting force is applied with the sling, the inclined orientation of the cross-piece causes the sling to slide on the cross-piece towards the corner between the cross-piece and the straight section. The link turns to said corner, causing the closure to open and the end link of the upper mooring chain to come out through the opening. In this sense, the two mooring chains can be disconnected underwater in a single operation, wherein the sling sliding on the cross-piece is pulled, without the need for the assistance of an ROV (unmanned remotely operated vehicle) to help the operation of disconnecting the two mooring chains.

[0007] GB2594990 shows another detachable mooring link comprising a generally C-shaped link body having a closed hole and a closable opening with a mouth. The link has a T-shaped closure to close the mouth. The link has a connection point for engaging a deployment device for holding and transporting the link. Summary of the invention

[0008] The object of the present invention is to provide a detachable mooring link, a connection system for connecting two mooring chains and a method for disconnecting two mooring chains underwater, as defined in the claims.

[0009] One aspect of the present invention relates to a detachable mooring link having an imaginary transverse plane passing through the geometric center of the detachable mooring link, dividing it into an upper portion for connecting an upper mooring chain and a lower portion for connecting a lower mooring chain. The detachable mooring link comprises a link body having an upper arched segment for connecting an upper mooring chain, a lower arched segment for connecting a lower mooring chain, and a straight segment to which the arched segments are attached. The link body has an opening closed by a closure between the two arched segments and has a connection point for receiving a lifting force, which causes the detachable mooring link to swing toward the opening to release the upper mooring chain through the opening, and wherein the connection point is arranged in an upper portion of the detachable mooring link located above the imaginary transverse plane.

[0010] The location of the connection point in the upper part of the link improves the maneuverability of the link when a vertical lifting force is applied to enable the two mooring chains to be disconnected underwater. When the connection point receives a lifting force, the detachable mooring link swings relative to the connection point. That is, the connection point is above the center of mass of the link body, which allows for better control of the swing of the detachable link when the detachable link is pulled vertically.

[0011] For example, in WO2020173925 A1, the connection point for receiving the lifting force is in the cross-piece, i.e. it is arranged in the lower part of the chain link, below the imaginary transverse plane, which may hinder the operation for disconnecting the chain underwater. In addition, the connection point is not fixed, but moves along the cross-piece as the lifting force is applied by the sling until the sling abuts against the straight section of the chain link; this may cause the sling to engage the cross-piece and cause the sling to wear due to friction.

[0012] Another aspect of the invention relates to a connection system comprising: a detachable mooring link as described above; a lower mooring chain having an end link connected to a lower arcuate section of the detachable mooring link; an upper mooring chain having an end link connected to an upper arcuate section of the detachable mooring link; and means for applying a lifting force at the connection point of the detachable mooring link.

[0013] One aspect of the invention relates to a method for disconnecting two mooring chains underwater, comprising:

[0014] Using a detachable mooring link as described above, the lower arched section of the mooring link is connected to the end link of the lower mooring chain, and the upper arched section of the mooring link is connected to the end link of the upper mooring chain,

[0015] Removing the closure from the opening using an ROV, and

[0016] Applying a lifting force at the connection point of the detachable mooring link to swing the detachable link towards the opening of the link body and release the end link of the upper mooring chain from the upper arched section of the link body.

[0017] These and other advantages and features of the present invention will become apparent in view of the accompanying drawings and detailed description of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 An exploded perspective view of an example of a detachable mooring link according to the present invention is shown. Figure 1 Also shown is an end link of a mooring chain connected to the detachable link.

[0019] Figure 2 A side view of the removable mooring link of the previous figure is shown without the closure.

[0020] Figure 3 A side view of the link from the previous figure is shown, with the closure piece closing the opening of the link body.

[0021] Figure 4 Shows Figure 3 A cross-sectional view of a chain link in which the closure is fixed to the straight section of the link body by screws.

[0022] Figure 5 Shows Figure 3 Another cross-sectional view of a link, but with the screw unscrewed and the closure not secured to the link body.

[0023] Figure 6 A side view of the link of the previous figure is shown, wherein the connection point where the lifting force is applied to cause the link to oscillate is observed.

[0024] Figure 7 Shows Figure 4 The enlarged details, and Figure 8 Shows Figure 5 Zoomed in details.

[0025] Figures 9 to 12 The procedure for the method of disconnecting two mooring chains underwater using the detachable links of the previous figures is shown. DETAILED DESCRIPTION

[0026] The present invention relates to a detachable mooring link 100 for connecting and disconnecting an upper mooring chain 200a and a lower mooring chain 200b underwater. The lower mooring chain 200b is directly or indirectly connected to an anchoring device for anchoring to the seabed, and the upper mooring chain 200a is directly or indirectly connected to a floating structure.

[0027] For the sake of clarity, only the end link 201a of the upper mooring chain 200a and the end link 201b of the lower mooring chain 200b are depicted in the figure.

[0028] The detachable mooring link 100 includes an imaginary transverse plane X passing through the geometric center of the detachable link 100, dividing it into an upper portion 100a and a lower portion 100b. The upper portion 100a is configured to connect to an upper mooring chain 200a, and the lower portion is configured to connect to a lower mooring chain 200b.

[0029] The detachable link 100 has a link body 110 having an upper arched segment 110a for connecting an upper mooring chain 200a, a lower arched segment 110b for connecting a lower mooring chain 200b, and a straight segment 110c to which the arched segments 110a and 110b are attached.

[0030] As in Figures 2 to 5 As can be seen in detail in FIG. 1 , the detachable link 100 has an annular configuration. Basically, a transverse imaginary plane X passes through the center of the link body 110 , dividing it into two symmetrical parts. The transverse imaginary plane X basically passes through the center of mass of the link body 110 .

[0031] As in Figure 3 As can be seen in FIG. 1 , the detachable mooring link 100 has an elongated annular shape in the form of an ellipse, with a first focus in the upper arched segment 110a and a second focus in the lower arched segment 110b (in FIG. Figure 3 The imaginary transverse plane X passes through the geometric center of the detachable mooring link 100, which is the midpoint of the line segment connecting the first focus and the second focus.

[0032] Preferably, the link body 110 is C-shaped. Even more preferably, the link body 110 has a cylindrical shape and is obtained by bending a cylindrical rod into a C-shape.

[0033] The link body 110 has an opening 111 between the two arched segments 110a and 110b, which is closed by a closure member 120. When the closure member 120 is arranged in the opening 111, the link body 110 and the closure member 120 form an integral link.

[0034] The upper arched segment 110a has a free end 110d and another end opposite to the free end 110d, the other end being attached to the straight segment 110c. The lower arched segment 110b has a free end 110e and another end opposite to the free end 110e, the other end being attached to the straight segment 110c. The opening 111 of the link body 110 is arranged between the free end 110d of the upper arched segment 110a and the free end 110e of the lower arched segment 110b.

[0035] The link body 110 has a connection point 112 for receiving a lifting force Lf, which causes the detachable link 100 to swing toward the opening 111 to release the upper mooring chain 200a from the upper arched section 110a of the link body 110 through the opening 111. Fig.11 and Fig.12 According to the present invention, the connection point 112 is arranged in the upper part 100a of the detachable link 100 located above the imaginary transverse plane X. In this sense, the connection point 112 is arranged above the center of mass of the link body 110, thereby improving the maneuverability of the detachable link 100 in the operation of disconnecting the mooring chains 200a and 200b.

[0036] Preferably, the connection point 112 is arranged in the straight section 100c of the link body 110 located above the imaginary transverse plane X. Therefore, the connection point 112 is arranged above the center of mass of the link body 110 and on the side opposite to the opening 111 to facilitate the swinging of the detachable link 100. Even more preferably, the connection point 112 is arranged in the upper part of the straight section 110c, in the area where the straight section 110c is attached to the upper arched section 110a. The area is defined by Figure 2 The curves and Figure 3 Even more preferably, the connection point 112 is arranged in the outer region of the upper part of the straight section 110 c , ie in the region which is as far as possible from the opening 111 , in order to improve the control of the oscillation of the detachable link 100 .

[0037] The connection point 112 comprises a hole 113 through the straight section 110c for receiving the device 10 for applying the lifting force Lf. The hole 113 allows the arrangement of a sling 10 which can be connected to a pulley block of the vessel for applying the lifting force Lf on the detachable link 100.

[0038] Preferably, if Figure 6As shown, the straight section 110c has a cylindrical shape, and the connection point 112 is formed by means of two recesses 117 made in the straight section 110c according to two planes of the cross section parallel to each other and parallel to the straight section 110c. In particular, the two planes of the cross section are parallel to the longitudinal axis of the cylindrical shape of the straight section 110c. The two recesses 117 facilitate the connection of the device 10 at the connection point 112. For example, the recess 117 facilitates the connection of the hook to the connection point 112.

[0039] The detachable link 100 further includes a cross-piece 130 disposed between the straight segment 110c and the free end 110e of the lower arched segment 110b, the cross-piece 130 being attached to the closure member 120. The cross-piece 130 increases the rigidity of the detachable link 100 and also serves to keep the closure member 120 attached to the detachable link 100, preventing the closure member 120 from being lost when removed from the opening 111, or preventing the ROV from having to store it when the opening 111 is not closed.

[0040] Preferably, the cross-piece 130 is attached to the closure 120 by means of a cord 140. Even more preferably, the cross-piece 130 is attached to the closure 120 by means of an elastic cord 140. In this sense, when the closure 120 is removed from the opening 111, the closure 120 is suspended from the removable link 100, hoping to be placed again in the opening 111. The elasticity of the cord 140 facilitates the maneuverability of the closure 120, since the elastic material of the cord 140 absorbs any vibrations that may occur.

[0041] Figure 1 1 shows how the cross member 130 can be coupled to the link body 110. Figure 1 As shown, the cross-piece 130 has a first end surrounding an annular groove 114 of the straight segment 110c and a second end surrounding another annular groove 115 of the free end 110e of the lower arcuate segment 110b. The cross-piece 130 is thus retained relative to the link body 110.

[0042] Moreover, if Figure 1As shown, the cross member 130 includes two parts 131 and 132, which can be separated from each other to disconnect the lower mooring chain 200b from the lower arched section 110b. The two parts 131 and 132 can be attached by a pin 133. Therefore, the end link 201b of the lower mooring chain 200b can be held in the lower arched section 110b of the link body 110 by the cross member 130. That is, the two parts 131 and 132 of the cross member 130 allow the lower mooring chain 200b to be connected to the detachable link 100, and basically the detachable link 100 is a part of the lower mooring chain 200b. For example, in a ship, the detachable link 100 can be connected to the lower mooring chain 200b attached to the anchor device, and the entire assembly of the detachable link 100, the chain 200b and the anchor device can be placed on the seabed, waiting for the upper mooring chain 200a to be connected.

[0043] The closure member 120 has a first portion 121 and a second portion 122 protruding vertically from the first portion 121 (see Figure 1 and Figure 3 ), so that when the closure member 120 closes the opening 111, the first portion 121 extends between the free end 110d of the upper arched segment 110a and the free end 110e of the lower arched segment 110b, and the second portion 122 extends from the first portion 121 to the straight segment 110c of the link body 110. Preferably, the closure member 120 is T-shaped.

[0044] When the closing piece 120 closes the opening 111, the detachable link 100 has an annular configuration similar to a conventional link of a mooring chain. The first portion 121 of the closing piece 120 serves as a straight section between the free ends 110e and 110d of the arched sections 110a and 110b. That is, the sections 110a, 110b, and 110c of the link body 110 and the first portion 121 of the closing piece 120 form the annular shape of the detachable link 100.

[0045] The second portion 122 of the closure 120 is coupled to one half of the straight section 110c. The second portion 122 ensures that the closure 120 is fixed in the link body 110 and also provides rigidity to the detachable link 100. The second portion 120 serves as a stud for a conventional link having a stud.

[0046] Preferably, the second portion 122 has a free end having a shape complementary to that of the straight segment 110c of the link body 110. The straight segment 110c is cylindrical and has a concave shape, and the free end of the second portion 122 of the closure 120 has a convex shape coupled to the concave shape of the straight segment 110c.

[0047] The free ends 110 d and 110 e of the arched segments 110 a and 110 b have a battlement shape that fits into a complementary shape of the free end of the first portion 121 of the closure 120 .

[0048] The closure 120 has a hole 123 in which a screw 124 passing through the first portion 121 and the second portion 122 of the closure 120 is received to fix the closure 120 to the straight section 110c of the link body 110. The screw 124 is actuated by the ROV to lock the closure 120 in the opening 111 of the link body 110. Even when the screw 124 is not fixed in the straight section 110c of the link body 110, the screw 124 remains in the hole 123 of the closure 120, and therefore, the ROV does not have to store the screw 124 during the operation of disconnecting the mooring chains 200a and 200b.

[0049] Preferably, the screw 124 has a threaded end for securing in the threaded hole 116 of the straight segment 110c of the link body 110. Alternatively, the screw 124 may be secured to the straight segment 110c with a pin.

[0050] The screw 124 has a first annular projection 125 which limits the axial displacement of the screw 124 in the hole 123 of the closure 120 between two stops 126 and 127 of the hole 123, as shown in FIG. Figure 7 and Figure 8 This can be observed in detail in the enlarged cross-sectional view.

[0051] The first stopper 126 is configured to contact the first annular protrusion 125 of the screw 124 and limit the tightening of the screw 124 in the threaded hole 116 of the straight section 110 c of the link body 110, while the second stopper 127 is configured to contact the first annular protrusion 125 of the screw 124 and limit the axial displacement of the screw 124, thereby preventing it from coming out of the hole 123.

[0052] like Figure 4 , Figure 5 , Figure 7 and Figure 8 As shown, the hole 123 has a first diameter in the second portion 122 of the closure 120, and it has a second diameter greater than the first diameter in the first portion 121 of the closure 120. In this sense, the second diameter defines a widened area of ​​the hole 123, in which the two stops 126 and 127 are located.

[0053] The first stop 126 is defined by a transition where the hole 123 transitions from the first diameter to the second diameter. The second stop 127 is formed by two pins passing through the hole 123 in the first part 121 of the closure 120, wherein the hole 123 has the second diameter.

[0054] Preferably, the screw 124 has a second annular protrusion 128 whose dimensions are complementary to the inner diameter of the hole 123 for a tight displacement of the second annular protrusion 128 in the hole 123 and for establishing a leak-proof closure of the hole 123. The diameter of the second annular protrusion 128 corresponds to the second diameter of the widened area of ​​the hole 123, so that the second annular protrusion 128 acts as a sealing gasket, preventing water from entering the hole 123.

[0055] The screw 124 has a handle 129 for operation by the ROV. The ROV is caused to rotate the handle 129 so as to screw the free end of the screw 124 into the hole 116 of the straight section 110c of the link body 110.

[0056] The first portion 121 of the closure member 120 has an insertion region, and the opening of the hole 123 into which the screw 124 is inserted is located in the insertion region. When the screw 124 is fixed in the straight section 110c to fix the closure member 120, the handle 129 of the screw 124 is located in the insertion region of the first portion 121 of the closure member 120, so that the handle 129 of the screw 124 does not protrude (see Figure 7 ). This allows the detachable link 100 to have an external geometry similar to a conventional link without having portions protruding from the external geometry of the link.

[0057] Thus, the method for disconnecting two mooring chains 200a and 200b underwater comprises the following steps.

[0058] In the first step, if Fig. 9 1 and 2. As shown, located underwater is a detachable mooring chain link 100, whose lower arched section 110b is connected to the end link 201b of the lower mooring chain 200b, and whose upper arched section 110a is connected to the end link 201a of the upper mooring chain 200b. Chain 200b will be coupled to an anchoring device for anchoring to the seabed, and chain 200a will be coupled to a floating structure, which is not shown for clarity. Fig. 9 Shown in.

[0059] In the second step, if Fig.10 As shown, the closure 120 is removed from the opening 111 using an ROV. In this sense, with the aid of the ROV, the handle 129 of the screw 124 is turned to loosen it from the hole 116 of the straight segment 110c of the link body 110, and then the screw 124 is pulled until the free ends 110d and 110e of the arched segments 110a and 110b are released from the closure 120. At this point, the first annular protrusion 125 of the screw 124 abuts against the second stopper 127 of the hole 123, as shown in FIG. Figure 8When the closure 120 has been removed from the opening 111, the ROV loosens the handle 129 of the screw 124 and the closure 120 is suspended from the cross-piece 130 by means of the rope 140 with the screw 124 remaining in the hole 123, whereby the ROV is free to perform other operations.

[0060] In the third step, if Fig.11 As shown, the lifting force Lf is applied to the connection point 112 of the detachable link 100 and the sling 10, so that the detachable link 100 swings toward the opening 111 of the link body 110, and the end link 201a of the upper mooring chain 200a is released from the upper arched section 110a of the link body 110, as shown in FIG. Fig.12 shown.

[0061] Thus, a connection system is obtained, which includes a detachable link 100, a lower mooring chain 200b having an end link 201b connected to the lower arched segment 110b of the detachable link 100, an upper mooring chain 200a having an end link 201a connected to the upper arched segment 110a of the detachable link 100, and a device 10 for applying a lifting force Lf at the connection point 112 of the detachable link 100.

[0062] As described above, the link body 110 of the detachable link 100 has the same external geometry as the end link 201b of the lower mooring chain 200b. Preferably, the detachable link 100 has the same external geometry as the external geometry of the remaining links of the mooring chains 200a and 200b, so that when the closure 120 is arranged to close the opening 111 of the link body 110, the detachable link 100 has the same external geometry as the external geometry of the remaining links, and the detachable link 100 behaves like another link in the chains 200a and 200b. This allows the entire assembly to be associated with other elements of the mooring line because the detachable link 100 has the same shape as the remaining links. For example, the chains 200a and 200b attached by the detachable link 100 can be passed through the tensioner of the mooring line, as shown in WO2019166674A1.

Claims

1. A detachable mooring chain link (100), the detachable mooring chain link having an imaginary transverse plane (X) passing through the geometric center of the detachable mooring chain link (100), the detachable mooring chain link being divided into an upper portion (100a) for connecting to an upper mooring chain (200a) and a lower portion (100b) for connecting to a lower mooring chain (200b), the detachable mooring chain link (100) comprising a chain link body (110), the chain link body having an upper arched section (110a) for connecting to the upper mooring chain (200a), a lower arched section (110b) for connecting to the lower mooring chain (200b), and a lower arched section (110a) for connecting to the upper mooring chain (200a). a lower arched section (110b) of a mooring chain (200b) and a straight section (110c) to which the arched sections (110a, 110b) are attached, the link body (110) having an opening (111) between the two arched sections (110a, 110b) closed by a closure (120) and having a connection point (112) for receiving a lifting force (Lf), the lifting force causing the detachable mooring link (100) to swing toward the opening (111) to release the upper mooring chain (200a) through the opening (111), It is characterized in that The connection point (112) is arranged in the upper portion (100a) of the detachable mooring link (100) located above the imaginary transverse plane (X).

2. The chain link according to claim 1, in, The connection point (112) is arranged in the straight section (110c) of the link body (110) which is located above the imaginary transverse plane (X).

3. The chain link according to claim 1 or 2, in, The connection point (112) includes a hole (113) passing through the straight section (110c) for receiving a device (10) for applying the lifting force (Lf).

4. Chain link according to the preceding claim, in, The straight section (110c) has a cylindrical shape and the connection point (112) is formed according to two planes of the cross section parallel to each other and to the straight section (110c) by means of two recesses (117) made in the straight section (110c).

5. The link according to any one of the preceding claims, further comprising a transverse piece (130) arranged between the straight segment (110c) and the free end (110e) of the lower arched segment (110b), the transverse piece (130) being attached to the closing piece (120).

6. Chain link according to the preceding claim, in, The cross member (130) is attached to the closure member (120) by an elastic cord (140).

7. The chain link according to claim 5 or 6, in, The cross member (130) has a first end surrounding an annular groove (114) of the straight section (110c) and a second end surrounding another annular groove (115) of the free end (110e) of the lower arched section (110b).

8. The chain link according to any one of claims 5 to 7, in, The cross-piece (130) comprises two parts (131, 132) which can be separated from each other to disconnect the lower mooring chain (200b) from the lower arched section (110b).

9. Chain link according to any one of the preceding claims, in, The closing member (120) has a first portion (121) and a second portion (122) protruding vertically from the first portion (121), so that when the closing member (120) closes the opening (111), the first portion (121) extends between the free end (110d) of the upper arched segment (110a) and the free end (110e) of the lower arched segment (110b), and the second portion (122) extends from the first portion (121) to the straight segment (110c) of the link body (110), and wherein the second portion (122) has a free end, and the shape of the free end of the second portion is complementary to the shape of the straight segment (110c) of the link body (110).

10. The chain link according to claim 9, in, The closure member (120) has a hole (123) in which a screw (124) is received that passes through the first portion (121) and the second portion (122) of the closure member (120) to fix the closure member (120) to the straight section (110c) of the link body (110).

11. Chain link according to the preceding claim, in, The screw (124) has a first annular protrusion (125) which limits the axial displacement of the screw (124) in the hole (123) of the closure (120) between two stops (126, 127) of the hole (123).

12. Chain link according to the preceding claim, in, The screw (124) has a second annular protrusion (128) whose size is complementary to the inner diameter of the hole (123) so that the second annular protrusion (128) is tightly displaced in the hole (123) and serves to establish a leak-proof closure of the hole (123).

13. A connection system comprising a detachable mooring link (100) according to any one of the preceding claims, a lower mooring chain (200b) having an end link (201b) connected to a lower arched section (110b) of the detachable mooring link (100), an upper mooring chain (200a) having an end link (201a) connected to an upper arched section (110a) of the detachable mooring link (100), and a device (10) for applying a lifting force (Lf) at a connection point (112) of the detachable mooring link (100).

14. System according to the preceding claim, in, The link body (110) of the detachable mooring link (100) has the same external geometry as the end link (201b) of the lower mooring chain (200b).

15. A method for disconnecting two mooring chains (200a, 200b) underwater, the method include: Using the detachable mooring link (100) according to any one of the preceding claims 1 to 12, the lower arched section (110b) of the mooring link (100) and the end link (201b) of the lower mooring chain (200b) The upper arched section (110a) of the mooring chain link (100) is connected to the end link (201a) of the upper mooring chain (200b), Removing the closure (120) from the opening (111) using an ROV, and Applying a lifting force (Lf) at the connection point (112) of the detachable mooring link (100) so as to swing the detachable mooring link (100) toward the opening (111) of the link body (110) and release the end link (201a) of the upper mooring chain (200a) from the upper arched section (110a) of the link body (110).

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