Device for reducing tensile load of offshore floating body

Abstract

A device for reducing the tensile load of an offshore floating body is provided. According to embodiments of the present invention, a tensile load caused by a mooring chain can be more efficiently reduced by using a pneumatic cylinder. In particular, through-holes are formed in the upper and lower portions of the pneumatic cylinder, and when a tensile load is applied by the mooring chain, air suction and air discharge can be alternately performed in each through-hole, thereby efficiently reducing the tensile load applied by the mooring chain.

Description

Tensile load reduction device for floating bodies offshore

[0001] Embodiments of the present invention relate to a technology for reducing the tensile load caused by a mooring chain that moors a floating body while the floating body heaves.

[0002] Generally, wind power generation involves converting wind energy into mechanical energy using devices such as wind turbines, which then power generators to generate electricity. Depending on the installation location, wind power generation can be categorized as onshore or offshore. Recently, research and development has been actively underway on floating offshore wind power, a type of offshore wind power generation where the lower floater is not fixed to the seabed but floats on the seabed.

[0003] Unlike fixed-type offshore wind turbines anchored to the seabed, the floating structures used in these floating offshore wind turbines are subject to the effects of marine environmental factors such as wind, waves, and currents. Accordingly, mooring chains are installed to stably anchor the floating structures, and fairleads are installed to connect the mooring chains to the floating structures.

[0004] At this time, in the process of installing mooring chains and fairleads, it is common to design the appropriate capacity of the fairleads and mooring chains within the allowable range of offset of the load due to the marine environment. However, in cases where the marine environment changes rapidly, the offset of the load due to the marine environment often goes beyond the allowable range.

[0005] To minimize the tensile load caused by such mooring chains, there are methods of reducing the tensile load by adjusting the weight of the mooring chain by connecting a buoyancy body to the mooring chain, or of adjusting the tensile load of the mooring chain by using an elastic body.

[0006] [Prior Art Literature]

[0007] (Patent Document 1) Korean Patent Publication No. 10-2404207 (May 26, 2022)

[0008] Embodiments of the present invention are intended to reduce the tensile load by a mooring chain by operating the piston rod of a pneumatic cylinder to alternate between tension and compression according to the direction in which the tensile load by the mooring chain is applied when the mooring chain moves due to the fluctuation of a floating body at sea.

[0009] According to a first embodiment of the present invention, a tensile load reduction device (100) for a marine float (B) is provided, which reduces a tensile load caused by a mooring chain (10) that is fixed to one surface of the marine float (B) and moors the marine float (B) during the process of heaving the marine float (B), comprising: a housing (102) fixed to one surface of the marine float (B); a plurality of pneumatic cylinders (104) having a piston (104a) provided therein, a first through-hole (104-1) and a second through-hole (104-2) formed at the upper and lower portions, respectively, and spaced apart from each other by a predetermined interval on the inner side of the housing (102); a piston rod (104b) having one end fixed to the lower portion of the piston (104a) and the other end extending outward from the housing (102); A weight (106) that moves up and down in conjunction with the piston rod (104b) according to the tension and compression of the piston rod (104b); a flexible wire (108) that is connected to the weight (106) and guides the up and down movement of the weight (106); And the other end of the piston rod (104b), one end and the other end of the flexible wire (108) are fixed and a load transfer plate (110) that moves up and down together with the piston rod (104b), the mooring chain (10) is tensioned through a chain connector (150) connected to the lower part of the load transfer plate (110), and when a tensile load by the mooring chain (10) is applied, air intake and air discharge in the first through hole (104-1) and the second through hole (104-2) are alternately performed, thereby reducing the tensile load by the mooring chain (10) by repeating tension and compression of the piston rod (104b).

[0010] As the piston rod (104b) is pulled outwardly from the pneumatic cylinder (104), air is sucked into the pneumatic cylinder (104) from the outside through the first through-hole (104-1) and at the same time, air is discharged from the inside of the pneumatic cylinder (104) to the outside of the pneumatic cylinder (104) through the second through-hole (104-2). As the piston rod (104b) is compressed inwardly from the pneumatic cylinder (104), air is discharged from the inside of the pneumatic cylinder (104) to the outside of the pneumatic cylinder (104) through the first through-hole (104-1) and at the same time, air can be sucked into the pneumatic cylinder (104) from the outside of the pneumatic cylinder (104) through the second through-hole (104-2).

[0011] The chain connector (150) is connected to the lower part of the load transfer plate (110) through a rotary arm (152), and a receiving groove (S) of a predetermined size is formed in the chain connector (150), and at least a part of a chain wheel (154) is received in the receiving groove (S), and the chain wheel (154) can guide the tensile direction of the mooring chain (10) while rotating while interlocked with the mooring chain (10).

[0012] At the lower part of the above chain connector (150), a plurality of pin joints (156) and a chain stopper (158) that opens and closes in conjunction with the pin joints (156) to secure the mooring chain (10) may be provided.

[0013] According to a second embodiment of the present invention, a tensile load reduction device (200) for a marine floating body is provided, which is connected to a rotary arm (204) of a fairlead (202) installed on one side of a marine floating body and rotates while the marine floating body heaves, and reduces a tensile load caused by a mooring chain (10) that moors the marine floating body, comprising: an upper frame (206) connected to the rotary arm (204); a pulley body locker (208) provided on a lower side of the upper frame (206) and having a hollow portion (H) of a predetermined size formed therein; a pulley body guide (210) provided on a lower side of the pulley body locker (208) and having at least a portion inserted into and fitted into the hollow portion (H); A pulley body (212) fixed to the lower surface of the pulley body guide (210) and moving up and down together with the pulley body guide (210), and having a receiving groove (S) of a predetermined size formed therein; a chain wheel (214) at least partially received in the receiving groove (S) and rotating while interlocked with the mooring chain (10) in a state in which the chain wheel is fastened to one side of the pulley body (212) to guide the tensile direction of the mooring chain (10); a plurality of pneumatic cylinders (216) having a piston (216a) provided therein, a first through hole (216-1) and a second through hole (216-2) formed at the upper and lower portions, respectively, and spaced apart from each other at a predetermined interval on the lower surface of the pulley body locker (208);And a piston rod (216b) having one end fixed to the lower part of the piston (216a) and the other end fixed to the lower frame (218), the mooring chain (10) vertically penetrates the lower frame (218) and is tensioned by engaging the chain wheel (214), and when a tensile load by the mooring chain (10) is applied, air intake and air discharge in the first through hole (216-1) and the second through hole (216-2) are alternately performed, thereby reducing the tensile load by the mooring chain (10) by repeating tension and compression of the piston rod (216b).

[0014] As the piston rod (216b) is pulled outwardly from the pneumatic cylinder (216), air is sucked into the pneumatic cylinder (216) from the outside through the first through-hole (216-1) and at the same time, air is discharged from the inside of the pneumatic cylinder (216) to the outside of the pneumatic cylinder (216) through the second through-hole (216-2). As the piston rod (216b) is compressed inwardly from the pneumatic cylinder (216), air is discharged from the inside of the pneumatic cylinder (216) to the outside of the pneumatic cylinder (216) through the first through-hole (216-1) and at the same time, air can be sucked into the pneumatic cylinder (216) from the outside of the pneumatic cylinder (216) through the second through-hole (216-2).

[0015] The above pulley body guide (210) may include a guide plate (210a) provided on the upper surface of the pulley body (212); and a plurality of protruding members (210b) that are formed to protrude in a direction perpendicular to the guide plate (210a) from the edge of the guide plate (210a) and are inserted into the hollow portion (H) during the up-and-down movement of the pulley body guide (210).

[0016] In the central portion of the above guide plate (210a), a buffer member (210c) is formed to protrude in a direction perpendicular to the guide plate (210a), and in the central portion of the hollow portion (H), a compression spring (208a) is provided, and as the pulley body guide (210) moves up and down, the compression spring (208a) can be compressed or stretched as it is pressed by the buffer member (210c).

[0017] At the lower end of the pulley body (212), a chain stopper (220) is formed to protrude at a predetermined angle, one end of the chain stopper (220) is fixed to the lower end of the pulley body (212), and the other end of the chain stopper (220) is formed to extend from one end of the chain stopper (220) but is spaced apart from the lower end of the pulley body (212) by a predetermined distance, and is connected to the pulling body (212) through a pulling jack (222), and as the other end of the chain stopper (220) is pulled toward the pulling body (212) by the pulling jack (222), the rotation of the chain wheel (214) is restricted, thereby fixing the mooring chain (10).

[0018] The other end of the chain stopper (220) is positioned outside the rotation radius of the chain wheel (214) and moves inside the rotation radius of the chain wheel (214) as it is pulled toward the pulling body (212) by the pulling jack (222), thereby limiting the rotation of the chain wheel (214).

[0019] According to embodiments of the present invention, the tensile load caused by a mooring chain can be more efficiently reduced by using a pneumatic cylinder. In particular, when a tensile load caused by a mooring chain is applied after forming through holes in the upper and lower portions of the pneumatic cylinder, the tensile load caused by the mooring chain can be efficiently reduced by alternating the air intake and air discharge in each through hole. Generally, a mooring chain that moors a floating body is used in a way that supports the entire tensile load according to the offset of the floating body through a fairlead installed on one side of the floating body. Referring to Fig. 1, a tensile load reduction device (100) is installed on one side of the upper portion of the floating body so as to enable maintenance without being submerged in the sea surface, and can reduce a certain portion of the entire tensile load supported by the fairlead. However, since a tensile load can be applied in a vertical direction by the fairlead installed in this manner, the second embodiment of the present invention is a method for integrating the function of the fairlead and operating without installing a separate fairlead.

[0020] In particular, according to the second embodiment of the present invention, the tensile load reduction device for a pneumatically operated offshore floating body is not directly fixedly installed on one side of the offshore floating body, but is indirectly connected to the offshore floating body through the first and second rotary arms connected to the fairlead, so that it can rotate up, down, left, and right more flexibly according to the movement of the mooring chain due to the sway of the offshore floating body. In this case, the stability of the tensile load reduction device for a offshore floating body is increased.

[0021] In addition, according to the second embodiment of the present invention, the structure and installation are simple compared to existing chain stoppers in that the mooring chain is fixed by restricting the rotation of the chain wheel through a pulling jack. In addition, in this case, instead of the chain stopper being directly connected to the mooring chain with a large movement due to shaking, there is an advantage in that the mooring chain can be fixed more efficiently with only a simple movement of the chain stopper near the rotation radius of the relatively large chain wheel. Specifically, in the process of installing the fairlead (202) of FIG. 7 on one side of the upper part of the floating body and installing the floating body through the rotary arm (204), the mooring chain is wound around the chain wheel (214) so ​​that a pre-tensioning operation for providing initial tension to the mooring chain is possible, and the chain stopper (220) for fixing the chain provides a locking function. Typically, a method in which a tensioner for performing such pre-tensioning work is additionally installed on the fairlead can be used, but in the second embodiment of the present invention, while performing the pre-tensioning work, the chain wheel and chain stopper to which the mooring chain is fixed are connected as one rigid structure by the upper frame (206), the pulley body locker (208), and the lower frame (218), so that the fairlead and the pulley body (212) support the entire tensile load, and the pneumatic cylinder can reduce a certain portion of the load in a situation in which the maximum tensile load due to the marine environment of the floating body appears.

[0022] Figure 1 is a schematic diagram for explaining a tensile load reduction device for a floating body on the sea according to the first embodiment of the present invention.

[0023] Figure 2 is a schematic diagram for explaining a tensile load reduction device for a floating body on the sea according to the first embodiment of the present invention.

[0024] Figure 3 is a drawing showing a chain connector connected to a tensile load reduction device of a floating marine body according to the first embodiment of the present invention.

[0025] Figure 4 is a drawing showing a detailed configuration of a tensile load reduction device for a floating body on the sea according to the first embodiment of the present invention.

[0026] FIG. 5 is a drawing for explaining a process of reducing the tensile load by a mooring chain in a tensile load reduction device for a floating body offshore according to the first embodiment of the present invention.

[0027] Figure 6 is a drawing for explaining the process of reducing the tensile load by the mooring chain in the tensile load reduction device of the floating body of the sea according to the first embodiment of the present invention.

[0028] Figure 7 is a drawing showing a detailed configuration of a tensile load reduction device for a floating body on the sea according to a second embodiment of the present invention.

[0029] Figure 8 is a drawing for explaining the process of reducing the tensile load by the mooring chain in the tensile load reduction device of the floating body of the sea according to the second embodiment of the present invention.

[0030] Figure 9 is a drawing for explaining the process of reducing the tensile load by the mooring chain in the tensile load reduction device of the floating body of the sea according to the second embodiment of the present invention.

[0031] FIG. 10 is a drawing for explaining the process of fixing a mooring chain to a chain stopper of a tensile load reduction device for a floating body offshore according to a second embodiment of the present invention.

[0032] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. The following detailed description is provided to facilitate a comprehensive understanding of the methods, devices, and / or systems described herein. However, these are merely examples and the present invention is not limited thereto.

[0033] In describing embodiments of the present invention, if a detailed description of a known technology related to the present invention is judged to unnecessarily obscure the gist of the present invention, the detailed description will be omitted. In addition, the terms described below are terms defined in consideration of their functions in the present invention, and this may vary depending on the intention or custom of the user or operator. Therefore, the definitions should be made based on the contents throughout this specification. The terminology used in the detailed description is only for the purpose of describing embodiments of the present invention and should not be limited in any way. Unless clearly used otherwise, the singular form includes the plural form. In this description, expressions such as "comprises" or "having" are intended to indicate certain features, numbers, steps, operations, elements, parts or combinations thereof, and should not be construed to exclude the presence or possibility of one or more other features, numbers, steps, operations, elements, parts or combinations thereof other than those described.

[0034]

[0035] Figures 1 and 2 are schematic diagrams illustrating a tensile load reduction device (100) for an offshore floating body according to a first embodiment of the present invention. In the present embodiments, the offshore floating body (B) is a floating structure installed at sea, and for example, a floating offshore wind power device (not shown) can be combined therewith.

[0036] As shown in FIGS. 1 and 2, the tensile load reduction device (100) of an offshore floating body is a device that is fixed to one side of an offshore floating body (B) and reduces the tensile load caused by a mooring chain (10) during the heaving process of the offshore floating body (B).

[0037] At this time, the chain connector (150) is connected to the lower part of the tensile load reduction device (100) of the offshore floating body through the rotary arm (152) described later, and the fairlead (170) can be placed on the lower side of the chain connector (150). One end of the mooring chain (10) is fixed to a suction anchor (160) installed on the seabed, and the other end can be connected to the tensile load reduction device (100) of the offshore floating body through the fairlead (170) and the chain connector (150).

[0038]

[0039] FIG. 3 is a drawing showing a chain connector (150) connected to a tensile load reduction device (100) of a floating body offshore according to the first embodiment of the present invention.

[0040] As illustrated in FIG. 3, the chain connector (150) can be connected to the lower portion of the tensile load reduction device (100) of the offshore floating body via the first rotary arm (152a) and the second rotary arm (152b). One end of the chain connector (150) can be connected to the second rotary arm (152b), and the second rotary arm (152b) can be connected to the first rotary arm (152a). At this time, the first rotary arm (152a) and the second rotary arm (152b) can be arranged to be staggered so as to rotate the chain connector (150) in different directions.

[0041] Additionally, a receiving groove (S) of a predetermined size may be formed in the chain connector (150). The receiving groove (S) is a groove for receiving a chain wheel (154), and may be formed, for example, along the length of the chain connector (150).

[0042] The chain wheel (154) is a device for guiding the tension direction of the mooring chain (10) while rotating while being engaged with the mooring chain (10), and at least a portion of the chain wheel (154) can be accommodated in the receiving groove (S). The chain wheel (154) is formed in a wheel shape, and a groove of a predetermined size can be formed in the center portion of the chain wheel (154) for the mooring chain (10) to be seated therein. Accordingly, the mooring chain (10) can be tensioned along the longitudinal direction of the chain connector (150) and its tension direction can be changed while passing through the chain wheel (154).

[0043] Additionally, a plurality of pin joints (156) and chain stoppers (158) may be provided at the bottom of the chain connector (150).

[0044] The pin joint (156) is connected to the chain stopper (158) to open and close the chain stopper (158). A plurality of pin joints (156) may be provided in a parallel state. At this time, both ends of the chain stopper (158) are connected to each pin joint (156) and can be opened and closed in conjunction with the pin joint (156). The pin joint (156) can operate under the control of a control unit (not shown) to open and close the chain stopper (158). When the chain stopper (158) is opened, the mooring chain (10) can move by engaging with the chain wheel (154), and when the chain stopper (158) is locked, the mooring chain (10) can be fixed by the chain stopper (158).

[0045]

[0046] Fig. 4 is a drawing showing a detailed configuration of a tensile load reduction device (100) for a floating marine body according to a first embodiment of the present invention. In addition, Figs. 5 and 6 are drawings for explaining a process of reducing a tensile load by a mooring chain (10) in a tensile load reduction device (100) for a floating marine body according to a first embodiment of the present invention.

[0047] Referring to FIGS. 4 to 6, a tensile load reduction device (100) of a floating body on the sea according to the first embodiment of the present invention includes a housing (102), a pneumatic cylinder (104), a weight (106), a wire wheel (107), a flexible wire (108), a load transfer plate (110), a reduction disk (120), an air compressor (122), and a solenoid valve (124).

[0048] The housing (102) is a cover for protecting the tensile load reduction device (100) of the offshore floating body, and may be formed in the shape of, for example, a rectangular parallelepiped. The housing (102) may be fixed to one surface of the offshore floating body (B). At this time, the inner surface of the housing (102) that is seated on one surface of the offshore floating body (B) may be formed to have a curvature corresponding to one surface of the offshore floating body (B). A pneumatic cylinder (104), a weight (106), a reduction disk (120), an air compressor (122), a solenoid valve (124), etc. may be provided on the inside of the housing (102).

[0049] The pneumatic cylinder (104) is a means used to reduce the tensile load by the mooring chain (10), and a plurality of pneumatic cylinders may be provided at a predetermined interval on the inside of the housing (102). A piston (104a) may be provided inside the pneumatic cylinder (104), and a piston rod (104b) may be provided at the bottom of the piston (104a). One end of the piston rod (104b) may be fixed to the bottom of the piston (104a), and the other end of the piston rod (104b) may be formed to extend to the outside of the housing (102) and be fixed to the load transfer plate (110). As described later, the piston rod (104b) can be tensioned (i.e., lowered) or compressed (i.e., raised) according to the tensile load by the mooring chain (10), and as the tension and compression of the piston rod (104b) are repeated, the tensile load by the mooring chain (10) can be reduced.

[0050] To this end, a first through hole (104-1) and a second through hole (104-2) may be formed in the upper and lower portions of the pneumatic cylinder (104), respectively. Specifically, the first through hole (104-1) may be formed in the upper portion of the pneumatic cylinder (104), and the second through hole (104-2) may be formed in the lower portion of the pneumatic cylinder (104). When a tensile load is applied by the mooring chain (10), air intake and air discharge in the first through hole (104-1) and the second through hole (104-2) are alternated, and thus tension and compression of the piston rod (104b) are repeated, thereby reducing the tensile load by the mooring chain (10).

[0051] As an example, as the piston rod (104b) is pulled outwardly from the pneumatic cylinder (104), air can be sucked from the outside of the pneumatic cylinder (104) into the inside of the pneumatic cylinder (104) through the first through hole (104-1), and at the same time, air can be discharged from the inside of the pneumatic cylinder (104) to the outside of the pneumatic cylinder (104) through the second through hole (104-2).

[0052] As another example, as the piston rod (104b) is compressed inwardly of the pneumatic cylinder (104), air can be discharged from the inside of the pneumatic cylinder (104) to the outside of the pneumatic cylinder (104) through the first through hole (104-1), and at the same time, air can be sucked from the outside of the pneumatic cylinder (104) to the inside of the pneumatic cylinder (104) through the second through hole (104-2).

[0053] The weight (106) moves up and down in conjunction with the piston rod (104b) according to the tension and compression of the piston rod (104b). The movement of the weight (106) can be guided by a flexible wire (108). The flexible wire (108) can be made of an elastic material and configured to be tensioned in one direction and then compressed in the opposite direction when the tension is released.

[0054] To this end, a guide rod (106a) may be formed extending in a direction parallel to the longitudinal direction of the pneumatic cylinder (104) on the inside of the housing (102). The weight (106) may be connected to the guide rod (106a) via a linkage member (106b), and may rise along the guide rod (106a) when tensile force is applied to the flexible wire (108). In addition, the weight (106) may descend along the guide rod (106a) by the restoring force of the flexible wire (108), and in this case, the piston rod (104b) may be compressed.

[0055] The flexible wire (108) can lift the weight (106) up and down while being wound around a plurality of wire wheels (107). The plurality of wire wheels (107) can be arranged at a predetermined interval with the weight (106) in between, and the weight (106) can be lifted up and down while the flexible wire (108) is wound around each of the plurality of wire wheels (107).

[0056] The load transfer plate (110) moves up and down together with the piston rod (104b) according to the tensile load by the mooring chain (10). The other end of the piston rod (104b) and one end and the other end of the flexible wire (108) are fixed to the load transfer plate (110), and a chain connector (150) can be connected to the lower part of the load transfer plate (110). As described above, when a tensile load by the mooring chain (10) is applied, the tension and compression of the piston rod (104b) can be repeated as air intake and air discharge from the through hole (104-1) and the second through hole (104-2) are alternated, thereby reducing the tensile load by the mooring chain (10).

[0057] Specifically, as the piston rod (104b) is pulled outwardly from the pneumatic cylinder (104), one end and the other end of the flexible wire (108) (i.e., the portion connected to the load transfer plate (110)) are pulled, thereby causing the weight (106) to rise, and as the piston rod (104b) is compressed inwardly from the pneumatic cylinder (104), one end and the other end of the flexible wire (108) (i.e., the portion connected to the load transfer plate (110)) are compressed, thereby causing the weight (106) to descend. In this way, the piston rod (104b) and the weight (106) operate in conjunction with each other, but can move up and down in opposite directions.

[0058] The deceleration disk (120) limits the rapid up-and-down movement of the weight (106) to prevent damage to the weight (106) and the pneumatic cylinder (104). When the piston rod (104b) is tensioned by the tensile load of the mooring chain (10), the weight (106) may move upward in the opposite direction to the tensioning direction of the piston rod (104b). In this case, the deceleration disk (120) can prevent damage to the weight (106) and the pneumatic cylinder (104) by decelerating the movement of the weight (106). To this end, the deceleration disk (120) can exert a force in a direction opposite to the upward direction of the weight (106) while having a weight of a predetermined size, thereby limiting the weight (106) from rising rapidly. However, this is only an example, and the method of limiting the rapid up-and-down movement of the weight (106) by the deceleration disk (120) is not limited to this.

[0059] The air compressor (122) and the solenoid valve (124) promote air intake and air discharge in the through hole (104-1) and the second through hole (104-2). When the piston rod (104b) is pulled outwardly from the pneumatic cylinder (104), the solenoid valve (124) can inject air from the air compressor (122) into the interior of the pneumatic cylinder (104) through the first through hole (104-1) and discharge the internal air of the pneumatic cylinder (104) to the air compressor (122) through the second through hole (104-2). When the piston rod (104b) is compressed inside the pneumatic cylinder (104), the solenoid valve (124) can inject air from the air compressor (122) into the interior of the pneumatic cylinder (104) through the second through hole (104-2) and discharge the internal air of the pneumatic cylinder (104) to the air compressor (122) through the first through hole (104-1).

[0060] In this way, according to the first embodiment of the present invention, when the mooring chain (10) moves due to the fluctuation of the floating body (B) on the sea, the piston rod (104b) of the pneumatic cylinder (104) operates to alternately tension and compression according to the direction in which the tensile load by the mooring chain (10) is applied, thereby reducing the tensile load by the mooring chain (10).

[0061] However, in the case of the tensile load reduction device (100) of the offshore floating body according to the first embodiment, since it is fixedly installed on one side of the offshore floating body (B) through the housing (102), there are bound to be some restrictions on the movement of the mooring chain (10). The mooring chain (10) can move up and down or left and right through the rotary arm (152) according to the rocking of the offshore floating body (B), but since the tensile load reduction device (100) of the offshore floating body is fixed to one side of the offshore floating body (B), if the tensile load by the mooring chain (10) and the movement due to the rocking exceed a critical value, there is a possibility that the tensile load reduction device (100) of the offshore floating body may be damaged. In addition, in the case of the tensile load reduction device (100) of the floating body offshore, the tensile load of the mooring chain (10) is reduced through the pneumatic cylinder (104), so the tensile load reduction device (100) of the floating body offshore including the pneumatic cylinder (104) cannot be positioned below the sea surface.

[0062] Accordingly, in the second embodiment described below, the problems of the first embodiment described above are supplemented to enable more stable reduction of the tensile load by the mooring chain (10). Hereinafter, the detailed configuration and operation of the tensile load reduction device (200) of a floating body on the sea according to the second embodiment of the present invention will be examined in detail with reference to FIGS. 7 to 10.

[0063]

[0064] Fig. 7 is a drawing showing a detailed configuration of a tensile load reduction device (200) for a floating body offshore according to a second embodiment of the present invention. In addition, Figs. 8 to 10 are drawings for explaining a process of reducing a tensile load by a mooring chain (10) in a tensile load reduction device (200) for a floating body offshore according to a second embodiment of the present invention.

[0065] Referring to FIGS. 7 to 10, a tensile load reduction device (200) of a floating body offshore according to a second embodiment of the present invention is a device that is connected to a rotary arm (204) of a fairlead (202) installed on one side of a floating body offshore (B) and rotates while the floating body offshore (B) sways, thereby reducing the tensile load caused by a mooring chain (10).

[0066] At this time, the rotary arm (204) may be composed of a first rotary arm (204a) and a second rotary arm (204b). The first rotary arm (204a) may be connected to the fairlead (202), and the second rotary arm (204b) may be connected to the first rotary arm (204a). The first rotary arm (204a) and the second rotary arm (204b) may be arranged in an alternating manner so as to rotate the tensile load reduction device (200) of the floating body on the sea in different directions.

[0067] As described below, the upper frame (206) can be connected to the second rotary arm (204b). In the case of the tensile load reduction device (200) of the marine floating body according to the second embodiment of the present invention, it is not directly fixedly installed on one side of the marine floating body (B), but is indirectly connected to the marine floating body (B) through the first rotary arm (204a) and the second rotary arm (204b) connected to the fairlead (202), so that it can be rotated up, down, left, and right more flexibly according to the movement of the mooring chain (10) due to the sway of the marine floating body (B), making it much more stable compared to the first embodiment.

[0068] The tensile load reduction device (200) of a floating body on the sea according to the second embodiment of the present invention includes an upper frame (206), a pulley body locker (208), a pulley body guide (210), a pulley body (212), a chain wheel (214), a pneumatic cylinder (216), a lower frame (218), and a chain stopper (220).

[0069] The upper frame (206) is provided on the upper portion of the tensile load reduction device (200) of the offshore floating body and is connected to the rotary arm (204). As described above, the upper frame (206) can be connected to the second rotary arm (204b). Accordingly, the tensile load reduction device (200) of the offshore floating body can freely move while rotating in multiple directions through the first rotary arm (204a) and the second rotary arm (204b).

[0070] The pulley body locker (208) is provided on the lower side of the upper frame (206) and may include a hollow portion (H) of a predetermined size. As an example, the pulley body locker (208) may be formed in a rectangular parallelepiped shape, and a hollow portion (H) of a predetermined size may be vertically protruded and formed in the center portion of the pulley body locker (208). As described below, the pulley body guide (210) may be inserted and fitted into the hollow portion (H) during the process of moving up and down.

[0071] In addition, a compression spring (208a) may be provided at the central portion of the hollow portion (H). The compression spring (208a) may be connected to the inner surface of the hollow portion (H) or to the lower surface of the upper frame (206) and may be arranged at the central portion of the hollow portion (H). As described below, the compression spring (208a) may be compressed or tensioned as it is pressed by the buffer member (210c) of the pulley body guide (210) during the up-and-down movement of the pulley body guide (210).

[0072] A pulley body guide (210) is provided on the lower side of the pulley body locker (208), and at least a portion thereof is inserted into and fitted into the hollow portion (H). The pulley body guide (210) may include a guide plate (210a), a protruding member (210b), and a buffer member (210c).

[0073] The guide plate (210a) is a plate provided on the upper surface of the pulley body (212) to be described later.

[0074] A plurality of protruding members (210b) may be provided at the edge of the guide plate (210a) in a direction perpendicular to the guide plate (210a). The protruding members (210b) may be formed to protrude from the edge of the guide plate (210a) in a direction perpendicular to the guide plate (210a) so that they may be inserted into and fitted into the hollow portion (H) during the up-and-down movement of the pulley body guide (210). The protruding members (210b) may be formed to protrude at a position corresponding to the inner surface of the hollow portion (H) so as to be fitted into and closely attached to the inner surface of the hollow portion (H).

[0075] The buffer member (210c) may be formed to protrude in a direction perpendicular to the guide plate (210a) from the central portion of the guide plate (210a). As described above, a compression spring (208a) may be provided in the central portion of the hollow portion (H). The compression spring (208a) may be compressed or tensioned as it is pressed by the buffer member (210c) of the pulley body guide (210) during the up-and-down movement of the pulley body guide (210). In this case, the buffer member (210c) may perform a buffering function according to the up-and-down movement of the pulley body guide (210).

[0076] The pulley body (212) is fixed to the lower surface of the pulley body guide (210) and moves up and down together with the pulley body guide (210). The pulley body (212) may be formed to extend along the longitudinal direction of the tensile load reduction device (200) of the offshore floating body from the lower surface of the pulley body guide (210). At this time, a receiving groove (S) of a predetermined size may be formed in the pulley body (212). The receiving groove (S) is a groove for receiving a chain wheel (214) to be described later, and may be formed, for example, along the longitudinal direction of the pulley body (212).

[0077] The chain wheel (214) is at least partially accommodated in the accommodation groove (S), and rotates while being engaged with the mooring chain (10) while being fastened to one side of the pulley body (212), thereby guiding the tension direction of the mooring chain (10). The chain wheel (214) is formed in a wheel shape, and a groove of a predetermined size for settling the mooring chain (10) may be formed in the center portion of the chain wheel (214). Accordingly, the mooring chain (10) may vertically penetrate the lower frame (218) described below, and then be engaged with the chain wheel (214) and tensioned, thereby changing its tension direction.

[0078] The pneumatic cylinder (216) is a means used to reduce the tensile load by the mooring chain (10), and may be formed in multiple numbers spaced apart from the lower surface of the pulley body locker (208) at a predetermined interval. A piston (216a) may be provided inside the pneumatic cylinder (216), and a piston rod (216b) may be provided at the lower portion of the piston (216a). One end of the piston rod (216b) may be fixed to the lower portion of the piston (216a), and the other end of the piston rod (216b) may be formed to extend outside the pneumatic cylinder (216) and be fixed to a lower frame (218) to be described later. As described later, the piston rod (216b) can be tensioned (i.e., lowered) or compressed (i.e., raised) according to the tensile load by the mooring chain (10), and as the tension and compression of the piston rod (216b) are repeated, the tensile load by the mooring chain (10) can be reduced.

[0079] To this end, a first through hole (216-1) and a second through hole (216-2) may be formed in the upper and lower portions of the pneumatic cylinder (216), respectively. Specifically, the first through hole (216-1) may be formed in the upper portion of the pneumatic cylinder (216), and the second through hole (216-2) may be formed in the lower portion of the pneumatic cylinder (216). When a tensile load is applied by the mooring chain (10), air intake and air discharge in the first through hole (216-1) and the second through hole (216-2) are alternated, and thus tension and compression of the piston rod (216b) are repeated, thereby reducing the tensile load by the mooring chain (10).

[0080] As an example, as the piston rod (216b) is pulled outwardly from the pneumatic cylinder (216), air can be sucked from the outside of the pneumatic cylinder (216) into the inside of the pneumatic cylinder (216) through the first through hole (216-1), and at the same time, air can be discharged from the inside of the pneumatic cylinder (216) to the outside of the pneumatic cylinder (216) through the second through hole (216-2).

[0081] As another example, as the piston rod (216b) is compressed inwardly of the pneumatic cylinder (216), air can be discharged from the inside of the pneumatic cylinder (216) to the outside of the pneumatic cylinder (216) through the first through hole (216-1), and at the same time, air can be sucked from the outside of the pneumatic cylinder (216) to the inside of the pneumatic cylinder (216) through the second through hole (216-2).

[0082] The lower frame (218) is provided at the lower portion of the tensile load reduction device (200) of the offshore floating body. As described above, the other end of the piston rod (216b) may be fixed to the lower frame (218). In addition, a hole (not shown) for passing a mooring chain (10) through the central portion of the lower frame (218) may be formed. Accordingly, the mooring chain (10) may be tensioned by vertically passing through the lower frame (218) and then engaging with the chain wheel (214).

[0083] The chain stopper (220) is installed at the bottom of the pulley body (212) and secures the mooring chain (10).

[0084] Referring to Fig. 10, the chain stopper (220) may be formed to protrude at a predetermined angle from the lower end of the pulley body (212). To this end, one end of the chain stopper (220) may be fixed to the lower end of the pulley body (212), and the other end of the chain stopper (220) may be formed to extend from one end of the chain stopper (220). At this time, the other end of the chain stopper (220) may be connected to the pulling body (212) through the pulling jack (222) while being spaced apart from the lower end of the pulley body (212) by a predetermined distance.

[0085] The pulling jack (222) interconnects the other end of the pulley body (212) and the chain stopper (220), and its length can be adjusted hydraulically or electrically.

[0086] As an example, when the pulling jack (222) is compressed (i.e., the length of the pulling jack (222) is reduced), the other end of the chain stopper (220) is pulled toward the pulling body (212), and the chain wheel (214) cannot rotate due to the other end of the chain stopper (220). That is, the other end of the chain stopper (220) is located outside the rotation radius of the chain wheel (214), and as it is pulled toward the pulling body (212) by the pulling jack (222), it moves inside the rotation radius of the chain wheel (214), thereby limiting the rotation of the chain wheel (214). In this case, since the chain wheel (214) no longer rotates, the position of the mooring chain (10) can be fixed.

[0087] As another example, when the pulling jack (222) is tensioned (i.e., the length of the pulling jack (222) increases), the other end of the chain stopper (220) moves away from the pulling body (212). In this case, since the other end of the chain stopper (220) is positioned outside the rotation radius of the chain wheel (214), the chain wheel (214) rotates. Accordingly, the mooring chain (10) can move without its position being fixed. In this state, if the mooring chain (10) is pulled out in the reverse direction, the mooring chain (10) can be separated, and in this case, the device becomes a tensile load reduction device for a floating marine body capable of detaching the mooring chain (10).

[0088] As described above, the tensile load reduction device (200) of a floating body on the sea according to the second embodiment of the present invention operates similarly to the tensile load reduction device (100) of a floating body on the sea according to the second embodiment in that it reduces the tensile load by the mooring chain (10) by using a pneumatic cylinder (216), and has an excellent effect in reducing the tensile load by the mooring chain (10).

[0089] Moreover, according to the second embodiment of the present invention, the tensile load reduction device (200) of a pneumatically operated offshore floating body is not directly fixedly installed on one side of the offshore floating body (B), but is indirectly connected to the offshore floating body (B) through the first rotary arm (204a) and the second rotary arm (204b) connected to the fairlead (202), so that it can rotate up, down, left, and right more flexibly according to the movement of the mooring chain (10) due to the sway of the offshore floating body (B). In this case, the stability of the tensile load reduction device (200) of the offshore floating body is increased.

[0090] In addition, according to the second embodiment of the present invention, the structure and installation are simple compared to existing chain stoppers in that the mooring chain (10) is fixed in a manner that limits the rotation of the chain wheel (214) through the pulling jack (222). In addition, in this case, instead of the chain stopper being directly fastened to the mooring chain (10) which moves greatly due to shaking, there is an advantage in that the mooring chain (10) can be fixed more efficiently with only a simple movement of the chain stopper (220) near the rotation radius of the relatively large chain wheel (214).

[0091]

[0092] While the present invention has been described in detail above through representative examples, those skilled in the art will understand that various modifications to the above-described embodiments are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims set forth below but also by equivalents thereof.

[0093] [Explanation of symbols]

[0094] 10: Mooring chain

[0095] 100, 200: Tensile load reduction device for floating bodies at sea

[0096] 102: Housing

[0097] 104: Pneumatic cylinder

[0098] 104a: Piston

[0099] 104b: Piston rod

[0100] 104-1: First through hole

[0101] 104-2: Second through hole

[0102] 106: Weight

[0103] 106a: Guide rod

[0104] 106b: Interlocking member

[0105] 107: Wire Wheel

[0106] 108: Flexible wire

[0107] 110: Load transfer plate

[0108] 120: Deceleration disc

[0109] 122: Air compressor

[0110] 124: Solenoid valve

[0111] 150: Chain Connector

[0112] 152: Rotary arm

[0113] 154: Chain wheel

[0114] 156: Pin joint

[0115] 158: Chain Stopper

[0116] 160: Suction anchor

[0117] 170, 202: Fairlead

[0118] 204: Rotary arm

[0119] 206: Upper frame

[0120] 208: Fully Body Locker

[0121] 208a: Compression spring

[0122] 210: Pulley Body Guide

[0123] 210a: Guide plate

[0124] 210b: Projecting member

[0125] 212: Fully body

[0126] 214: Chain wheel

[0127] 214a: Fastening member

[0128] 216: Pneumatic cylinder

[0129] 216a: Piston

[0130] 216b: Piston rod

[0131] 216-1: First through hole

[0132] 216-2: Second through hole

[0133] 218: Lower frame

[0134] 220: Chain Stopper

[0135] 222: Pulling Jack

Claims

1. A tensile load reduction device (200) for an offshore floating body that is connected to a rotary arm (204) of a fairlead (202) installed on one side of an offshore floating body and rotates during the heaving process of the offshore floating body, and reduces the tensile load caused by a mooring chain (10) that moors the offshore floating body. An upper frame (206) connected to the above rotary arm (204); A pulley body locker (208) provided on the lower side of the upper frame (206) and having a hollow portion (H) of a predetermined size formed therein; A pulley body guide (210) provided on the lower side of the above pulley body locker (208), at least a portion of which is inserted into and fitted into the hollow portion (H); A pulley body (212) fixed to the lower surface of the pulley body guide (210) and moving up and down together with the pulley body guide (210), and having a receiving groove (S) of a predetermined size formed therein; A chain wheel (214) that is at least partially accommodated in the above-mentioned accommodation groove (S) and rotates while being engaged with the mooring chain (10) in a state of being fastened to one side of the pulley body (212) to guide the tension direction of the mooring chain (10); A plurality of pneumatic cylinders (216) having a piston (216a) provided inside, a first through hole (216-1) and a second through hole (216-2) formed at the upper and lower portions, respectively, and spaced apart from each other at a predetermined interval on the lower surface of the pulley body locker (208); and It includes a piston rod (216b) whose first end is fixed to the lower part of the piston (216a) and whose other end is fixed to the lower frame (218). The above mooring chain (10) is tensioned by vertically penetrating the lower frame (218) and engaging with the chain wheel (214). A tensile load reduction device for a floating body on the sea, which reduces the tensile load by the mooring chain (10) by repeating tension and compression of the piston rod (216b) while alternating air intake and air discharge in the first through hole (216-1) and the second through hole (216-2) when a tensile load is applied by the mooring chain (10).

2. In claim 1, A device for reducing the tensile load of a floating body on the sea, wherein, as the piston rod (216b) is tensioned toward the outside of the pneumatic cylinder (216), air is sucked from the outside of the pneumatic cylinder (216) into the inside of the pneumatic cylinder (216) through the first through-hole (216-1) and, at the same time, air is discharged from the inside of the pneumatic cylinder (216) to the outside of the pneumatic cylinder (216) through the second through-hole (216-2), and, as the piston rod (216b) is compressed toward the inside of the pneumatic cylinder (216), air is discharged from the inside of the pneumatic cylinder (216) to the outside of the pneumatic cylinder (216) through the first through-hole (216-1) and, at the same time, air is sucked from the outside of the pneumatic cylinder (216) into the inside of the pneumatic cylinder (216) through the second through-hole (216-2).

3. In claim 1, The above pulley body guide (210) is A guide plate (210a) provided on the upper surface of the above pulley body (212); and A tensile load reduction device for a floating body offshore, comprising a plurality of protruding members (210b) formed to protrude in a direction perpendicular to the guide plate (210a) from the edge of the guide plate (210a) and inserted into the hollow portion (H) during the up-and-down movement of the pulley body guide (210).

4. In claim 3, In the central portion of the above guide plate (210a), a buffer member (210c) is formed to protrude in a direction perpendicular to the above guide plate (210a), In the central part of the above hollow portion (H), a compression spring (208a) is provided. A device for reducing the tensile load of a floating body on the sea, in which the compression spring (208a) is compressed or tensioned as it is pressurized by the buffer member (210c) during the up-and-down movement of the pulley body guide (210).

5. In claim 1, At the bottom of the above pulley body (212), a chain stopper (220) is formed to protrude at a predetermined angle, One end of the above chain stopper (220) is fixed to the lower end of the pulley body (212), The other end of the chain stopper (220) is formed to extend from one end of the chain stopper (220), but is connected to the pulling body (212) through a pulling jack (222) while being spaced apart from the lower end of the pulley body (212) by a predetermined distance. A device for reducing the tensile load of a floating body offshore, in which the mooring chain (10) is fixed by restricting the rotation of the chain wheel (214) as the other end of the chain stopper (220) is pulled toward the pulling body (212) by the pulling jack (222).

6. In claim 5, A device for reducing the tensile load of a floating body on the sea, wherein the other end of the chain stopper (220) is positioned outside the rotation radius of the chain wheel (214) and moves inside the rotation radius of the chain wheel (214) as it is pulled toward the pulling body (212) by the pulling jack (222), thereby limiting the rotation of the chain wheel (214).

Images