This invention relates to an apparatus for connecting a mooring line, a system for connecting a mooring line, and a method of use of the apparatus or system for connecting a mooring line. The mooring line may be a mooring line for a vessel, an offshore structure, floating structure, an anchor, buoy or the like.
Offshore structures, such as floating structures or platforms, may be moored by mooring lines, such as mooring chains. A tension may be applied to each of the mooring lines, for example, by the use of a tensioning apparatus. The application of tension may serve to moor the floating structure or platform in a desired position.
A mooring apparatus may require assembly before a tension is applied to the mooring line. Assembly may include direct or indirect connection of at least one mooring line to the structure to be moored and direct, or indirect, coupling of each mooring line to another structure, such as an anchor or pile located on the seabed.
The mooring lines, and in particular the ends of the mooring lines, may comprise chains. A connection between a vessel, anchor, or the like, to a chain which may, in use, be under tension, may be prone to stress and wear.
In an offshore environment, because of a relative movement between a vessel, a mooring line and a anchoring point, there may be a degree of movement at a connection between the mooring line and the vessel and/or anchoring point. Such movement may further stress and wear the mooring line and connection components. The relative movement may cause Out of Plane Bending (OPB) fatigue, which may exacerbate the wear of the mooring components.
The use of structures such as lever arms and fairleads, to minimise the effects of OPB, is known. However, such structures may be large, heavy, expensive and difficult to install, operate and/or maintain.
Further, the installation and maintenance of such structures in an offshore or underwater environment may require high levels of skill, the use of divers, operators, and/or underwater Remotely Operated underwater Vehicles (ROVs), and may incur significant expense and risk.
It is an object of at least one embodiment of at least one aspect of the present invention to obviate or at least mitigate one or more problems in the prior art.
It is an object of at least one embodiment of at least one aspect of the present invention to provide a technically simple and/or commercially more cost effective method and apparatus for mooring than in the prior art.
According to a first aspect of the present invention there is provided a mooring apparatus. The mooring apparatus may comprise a socket. The mooring apparatus may comprise a connection member. The mooring apparatus may comprise an arrangement for positioning and/or controlling the disposition of the connection member relative to the socket. The connection member may be receivable and/or retainable in the socket.
The Applicant calls this apparatus a “Pull-In Uni-Joint”.
The socket may comprise at least one seat, and optionally at least a portion of the at least one seat may be substantially U-shaped, hook-shaped or J-shaped.
The connection member may comprise at least one projection, such as a trunnion, and optionally the connection member may comprise a pair of projections or trunnions which may be receivable/retainable on a/the at least one seat. The connection member may be adapted to rotate/be rotatable on the at least one seat around a/the first axis defined by a/the at least one projection.
The connection member may comprise a joint defining a second axis about which at least a portion of the connection member may be adapted to rotate. At least a portion of the connection member may be adapted to rotate around the first axis and/or the second axis.
The positioning arrangement may comprise a guide such as a sheave or a chain wheel, and optionally which a/the line extends around. The positioning arrangement may comprise a line engaging apparatus disposed on, connected to, and/or associated with, the connection member.
In use, the line may extend from the connection member and/or the line engaging apparatus around the guide.
The seat, or a base of the seat, or receiving portion or weight-bearing portion of the seat, may at least partially or substantially face toward, or may be oriented in the direction of, the guide.
The connection member may be for connecting, such as disconnectably connecting, to a mooring line. The connection member may be provided with an arrangement for connecting, such as disconnectably connecting, the apparatus to a mooring line.
Preferably the connection member may be removably retainable in the socket.
Preferably the connection member may be removably receivable in the socket.
Preferably the connection member may comprise a line engaging apparatus. In use, a first portion of a line may be connected to the line engaging apparatus.
The positioning arrangement may comprise the line.
The positioning arrangement may comprise a guide. The guide may be a sheave or a wheel, such as a chain wheel or the like. The guide may be a pulley, or a component of a pulley mechanism. In use, the line may extend from the connection member around the guide.
The socket may comprise at least one seat. The at least one seat may be substantially hook-shaped.
A distal end of the connection member may be adapted for connecting the apparatus to a mooring line, or the like. In use, which may include positioning of the connection member, the mooring line may be under tension.
The line engaging apparatus may be positioned at a proximal end of the connection member.
The line may be a wire, a rope, a chain, or the like. In use, the line may extend around and/or about and/or through the positioning arrangement.
The socket may comprise at least one guide portion.
In use, a pulling force on a second portion of the line, the pulling force being in a direction away from the guide, may pull the first portion of the line towards the guide.
The pulling force may pull the connection member towards and/or into the socket and/or onto a guide portion. In use, a reduction in the pulling force on a second portion of the line, the pulling force being in a direction away from the guide, may move the connection member into the seat. The connection member may move towards the seat under the force of gravity and/or under a force induced by a tension, such as a mooring tension in the mooring line. The connection member may move towards the seat along the guide portion.
The pulling force may pull the connection member towards and/or out of the socket and/or along a guide portion and/or away from a guide portion. In use, a reduction in the pulling force on a second portion of the line, the pulling force being in a direction away from the guide, coupled with a further pulling force applied to the connection member, may move the connection member out of the socket and/or in a direction away from the socket.
The further pulling force may be applied by a support line, a lifting wire, a lifting line, a bridle, or the like.
The connection member may comprise a lever arm.
The connection member may comprise at least one cylindrical projection, such as a trunnion or the like. The connection member may comprise a pair of trunnions. The at least one cylindrical projection may be adapted to fit and/or sit in the at least one seat. The at least one cylindrical projection may be retained by the at least one seat.
The apparatus may comprise a retaining pin. The retaining pin may be adapted to restrict movement of the connection member when the connection member is positioned on the at least one seat.
Each connection member may comprise at least one retaining member.
The connection member and/or the retaining member may comprise at least one shoulder or wing. The connection member or the retaining member may comprise a pair of shoulders or wings. The at least one shoulder or wing may be adapted to move around and/or rotate around or about an outer surface of the seat. The connection member may be adapted to be located in a retained position within and/or by the or each socket. In the retained position, the seat may be located between the at least one cylindrical projection and the at least one shoulder or wing.
The apparatus may be adapted for connection to, or mounting on or in, a structure. The structure may be a floating structure, a vessel or the like. The structure may be an anchor, a pile, such as a suction pile, gravity anchor, or the like.
In use, such as during installation and/or stowage and/or removal, replacement or maintenance of the apparatus, the at least a portion of the connection member may be at least partially submerged.
In use, such as during installation and/or stowage and/or removal, replacement or maintenance of the apparatus, the apparatus, or at least a portion of the apparatus, may be completely above a water line, completely below the water line, or at least partially submerged.
Advantageously, the apparatus described above does not require implementation of a load bearing pin. Instead, in the present invention, a load is carried by the at least one seat. Having a connection that does not require a load bearing pin is advantageous for high load mooring lines as the Minimum Breaking Load (MBL) directly relates to the load pin size. Very large and heavy load pins add more risk and potentially more cost to the installation.
Advantageously, minimal connection member retaining features are required, since the connection member is subject only to a small degree of over rotation during installation, resulting in a lighter, smaller and cheaper apparatus.
Advantageously, the apparatus described above enables a fully assembled mooring line to be pulled into a socket while the mooring line is under tension. As such, the apparatus may be used with or without a mooring line tensioner in the system.
According to a second aspect of the present invention mere is provided a method of configuring a mooring apparatus, wherein the method comprises:
providing a mooring apparatus according to the first aspect of the present invention, the method further comprising:
connecting a first portion of a line to a line engaging apparatus; and
positioning or extending the line around the positioning arrangement.
The positioning arrangement may comprise a guide.
To retain the connection member in the socket, the method may comprise applying a pulling force on a second portion of the line, the pulling force being in a direction away from the guide, such that the first portion of the line moves towards the guide.
To retain the connection member in the socket, the method may comprise reducing a pulling force on a second portion of the line, the pulling force being in a direction away from the guide, such that the connection member moves into the seat.
To remove the connection member from the socket, the method may comprise the step of applying a pulling force to the second portion of the line, the pulling force being in a direction away from the guide, such that the first portion of the line moves towards the guide.
To remove the connection member from the socket, the method may comprise the step of reducing a reducing a pulling force on a second portion of the line, the pulling force being in a direction away from the guide, coupled with applying a further pulling force to the connection member in a direction away from the socket.
According to a third aspect of the present invention there is provided a mooring system, the mooring system comprising the mooring apparatus according to the first aspect of the present invention.
The system may comprise a plurality of mooring apparatuses according to the first aspect of the present invention.
The system may comprise a mooring line. At least a portion of the mooring line may comprise a chain.
The system may comprise a support line. At least a portion of the support line may comprise a chain.
The system may comprise a structure. The structure may be a subsea structure, such as an anchor, a suction pile, a gravity anchor, or the like. The structure may be located on or near to a seabed.
The structure may comprise at least one socket.
The mooring line may be connected to the connection member. The mooring line may be connected to a distal end of the connection member.
The support line may be connected to the connection member. The support line may be connected to a distal end of the connection member.
Advantageously, the apparatus, system and/or method described herein may permit the mooring line to be pre-cut to size and installed without a tensioning device on such, since the mooring line can be pulled in at a tension above the nominal/design tension of the mooring line to a “pulled in” position and then lowered down to the seat to achieve a design tension.
It should be understood that the features defined above in accordance with any aspect of the present invention or below relating to any specific embodiment of the invention may be utilised, either alone or in combination with any other defined feature, in any other aspect or embodiment or to form a further aspect or embodiment of the invention.
These and other aspects of the present invention will now be described, by way of example only, with reference to the accompanying drawings, which are:
Referring firstly to
Each mooring apparatus 10a; 10b; 10c; 10d comprises a socket 15a; 15b; 15c; 15d, a connection member 20a; 20b; 20c; 20d, and an arrangement 25a; 25b; 25c; 25d for positioning the connection member 20a; 20b; 20c; 20d relative to the socket 15a; 15b; 15c; 15d, the connection member 20a; 20b; 20c; 20d being retainable in the socket 15a; 15b; 15c; 15d. The connection member 20a; 20b; 20c; 20d is removably retainable in the socket 15a; 15b; 15c; 15d. The connection member 20a; 20b; 20c; 20d is removably receivable in the socket 15a; 15b; 15c; 15d.
The connection member 20a; 20b; 20c; 20d comprises a line engaging apparatus 30a; 30b; 30c; 30d. Each connection member 20a; 20b; 20c; 20d comprises a lever arm.
A first portion of a line 35 is connected to the line engaging apparatus 30a. The positioning arrangement 25a comprises a guide 25a. The guide 25a is a sheave. In other embodiments encompassing the inventive concept of the present invention, the guide 25a can be a wheel, such as a chain wheel or the like, or the guide 25a can be a pulley, or a component of a pulley mechanism.
Each socket 15a comprises a pair of seats 40a, 40b. Each seat 40a, 40b is substantially hook-shaped. One will appreciate that in variations of a design that encompass the inventive concept of the present invention, each seat 40a, 40b can be substantially J-shaped, or “reverse-J” shaped, or cup-shaped. Each seat 40a, 40b is a boss or protuberance.
A distal end 55a of the connection member 20a is adapted for connecting the apparatus 10a to a mooring line 60, or the like. In use, the mooring line 60 can be under tension, such as a mooring tension. Typically, at least a portion of the mooring line 60 comprises a chain.
A distal end 55a of the connection member 20a is adapted for connecting the apparatus 10a to a support line 80, or the like. In use, the support line 80 can position the connection member 20a, as will be described below. At least a portion of the support line 60 can comprise a chain.
The line engaging apparatus 30a is positioned at a proximal end 56a of the connection member 20a. The line 35, 35′ can be a wire, a rope, a chain, or the like. In use, the line 35, 35′ extends around and/or about and/or through the positioning arrangement 25a.
The socket 15a comprises a guide portion 65. The guide portion 65 extends to a limiting portion 70. The limiting portion 70 limits a degree of movement of the connection member 20a within the socket 15a. The limiting portion 70 stops the connection member 20a interfering with the guide 25a during removal and/or installation of the connection member 20a within the socket 15a. The guide portion 65 is a boss or protuberance.
The connection member 20a comprises a pair of trunnions 90a, 90b. The pair of trunnions 90a, 90b are adapted to fit and/or sit in the pair of seats 40a, 40b. The pair of trunnions 90a, 90b are adapted to retained by the pair of seats 40a, 40b. Referring now to
In use, the pulling force pulls the connection member 20a towards and into the socket 15a and onto the guide portion 65.
Referring now to
Referring now to
The apparatus 10a; 10b; 10c; 10d can optionally comprises a retaining pin 95. The retaining pin 95 is adapted to restrict movement of the connection member 20a when the connection member 20a is positioned on the pair of seats 40a, 40b.
Referring now to
In order to remove a connection member 20a from a socket 15a, the installation process is essentially reversed. That is, a pulling force is applied to the second portion 35′ of line 35, 35′. The pulling force pulls the connection member 20a towards and/or out of the socket 15a and/or along the guide portion 65 and/or away from the guide portion 65. Next, a reduction in the pulling force on a second portion 35′ of the line, the pulling force being in a direction away from the guide 25a, coupled with a further pulling force applied to the connection member 20a, moves the connection member 20a out of the socket 15a and/or in a direction away from the socket 15a. The further pulling force is applied to the support line 80. The support line 80 comprises a bridle 85 to maintain the orientation of the connection member 20a during installation and/or removal.
Each retaining member 130a; 130b; 130c; 130d comprises a pair of shoulders or wings 140a; 140b; 140c; 140d. The pair of shoulders or wings 140a; 140b; 140c; 140d is adapted to move around and/or rotate around or about an outer surface of each pair of seats 150a; 150b; 150c; 150d. Each connection member 120a; 120b; 120c; 120d is adapted to be located in a retained position by each pair of shoulders or wings 140a; 140b; 140c; 140d. In the retained position, each pair of seats 150a; 150b; 150c; 150d is located between each pair of trunnions 90a, 90b and each pair of shoulders or wings 140a; 140b; 140c; 140d.
Referring now to
The mooring apparatus 300 comprises a connection member 320a. The connection member 320a is receivable within socket 15a.
The connection member 320a comprises a tensioner apparatus 330. The tensioner apparatus 330 comprises a frame 335 and a guide portion 340 for guiding a portion of a chain 345. The guide portion 340 is a chain wheel. The tensioner apparatus 330 comprises a locking means 350. The locking means 350 is a chain stopper. The guide portion 340 is moveably connected to the frame 335. The locking means 350 is pivotably connected to the frame 335.
In an engaged position, as shown in
It will be appreciated that the embodiments of the present invention herebefore described are given by way of example only and are not meant to limit the scope of thereof. It will be appreciated that embodiments of the present invention provide benefits over the prior art.
In the embodiments of the present invention shown in
Advantageously, the apparatus, system and method described herein may permit the mooring line to be pre-cut to size and installed without a tensioning device on such, since the mooring line can be pulled in at a tension above the nominal/design tension of the mooring line to a “pulled in” position and then lowered down to the seat to achieve a design tension.
Number | Date | Country | Kind |
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1706745.5 | Apr 2017 | GB | national |
1711907.4 | Jul 2017 | GB | national |
Filing Document | Filing Date | Country | Kind |
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PCT/GB2018/051102 | 4/26/2018 | WO | 00 |