JP2001001980A - Floating body mooring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To operate a weather vane quickly and surely, thereby avoiding an excessive force applied on a mooring line, resulting in preventing a rupture aocident from oocurring. SOLUTION: A relatively tight mooring with mooring lines 5, 6 is applied on both sides close to a bow of a hull 1, and a relatively loose mooring with a mooring line 7 from a rearward is applied on a stern, thereby allowing the stern side to move rearward aocording to an external force. Tension sensors 11, 12 are provided on the mooring lines 5, 6 to measure tensile forces applied on the left and right mooring lines 5, 6. A thruster 13 and a drive device 14 are provided on the stern of the hull 1. Signals measured by the tension sensors 11, 12 are supplied for a control device 15. The control device is provided with a processor, calculates an applied direction of an external force applied on the hull 1 from the tensile forces measured by the left and right tension sensors 11, 12, and drives the thruster 13 based on the calculation result to control to direct the hull 1 in the applied direction of the external force.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floating body mooring apparatus for mooring a floating body such as a ship on the sea.

[0002]

2. Description of the Related Art Conventionally, there is a one-point mooring system for mooring a floating body of a ship or the like in, for example, an offshore oil shipping facility, an offshore oil production system and an oil storage tank, and various types of survey equipment at sea.

As the above-mentioned one-point mooring method, a turntable (Turret) type one-point mooring method shown in FIG. 6 is generally used. In this swivel type one-point mooring system, a turret 2 capable of rotating by 360 ° is provided at a position near a bow of a floating body, for example, a hull 1, and the turret 2 is connected to a plurality of mooring lines 3 using chains, wires, and the like and anchors (not shown). ) And the like, so that the stern side can freely move sideways as shown by arrow a.

In the above-described swivel-type one-point mooring system, the hull 1 is weathervaned by applying an external force such as a tidal current, a wave, or wind to the hull 1 by rotatably mooring a position near the bow of the hull 1. That is, the longitudinal direction of the hull 1 is always oriented in the direction of the external force, so that the influence of the external force on the hull is reduced.

In this swivel type one-point mooring system, the turret 2 has a very large diameter of, for example, about 15 to 20 m, and is extremely difficult to machine, requires a swivel joint for pipe connection, and is expensive. Problem.

For this reason, a mooring system which can be constructed at a low cost as shown in FIG. 7 has been developed in place of the above-mentioned expensive swivel type single point mooring system. In this mooring method, both sides near the bow of the hull 1 are relatively moored by mooring lines 5, 6 and anchors (not shown), and the stern is moored by mooring lines 7 and anchors (not shown). Mooring is performed relatively loosely from the rear. In this mooring system, the stern is moored relatively gently by the mooring line 7, so that when an external force such as a tide, a wave, or a wind is applied to the hull 1, the stern side responds to the external force as indicated by an arrow a. Moving to the side, the operation of the weather vane is performed. When this mooring method is used, the range in which the stern can move is limited.However, the range of the direction in which the external force is generated is investigated in advance according to the installation sea area, and the direction of the hull, the vicinity of the bow, and the vicinity of the stern are determined accordingly. Determine the strength of the mooring.

[0007]

The mooring method shown in FIG. 7 does not require a turret 2, a swivel joint for connecting pipes, and the like, so that it can be constructed at a low cost. However, when external forces such as tidal currents, waves, and wind suddenly change, the weather vane cannot follow in time, as with the swivel point one-point mooring system.
The mooring line may be broken due to excessive tension.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the operation of a weather vane can be performed quickly and reliably, without applying excessive tension to a mooring line.
An object of the present invention is to provide an inexpensive floating body mooring device capable of preventing a breakage accident beforehand.

[0009]

According to a first aspect of the present invention, there is provided a floating body mooring device for mooring a floating body on the sea, wherein the floating body is harder at the front left and right sides, near the rear end, and near the rear end. Mooring means for mooring on the mooring line, a thruster provided at the rear end of the floating body, a tension sensor for measuring the tension of a mooring line for mooring the left and right sides near the front end of the floating body, and a tension sensor for measuring the tension Calculating means for determining the acting direction of the external force applied to the floating body from the tension,
A drive unit for driving the thruster so that the direction of action of the external force obtained by the calculation unit and the floating body are parallel to each other is provided.

According to a second aspect of the present invention, there is provided a floating body mooring apparatus for mooring a floating body offshore, wherein the mooring line is moored on the left and right sides near the front end and near the rear end of the floating body with mooring lines having different characteristics at the front end near the rear end. Means, a mooring line laterally attached to the rear end of the floating body, a winch for lifting and extending the mooring line to move the rear end of the floating body to the side, and mooring the left and right sides near the front end of the floating body. A tension sensor that measures the tension of the mooring line, a computing unit that determines the direction of action of the external force applied to the floating body from the tension measured by the tension sensor, and the action direction of the external force determined by the computing unit is parallel to the floating body. And a driving means for driving the winch.

According to a third aspect of the present invention, there is provided a floating body mooring device for mooring a floating body offshore, wherein mooring means for mooring both sides near the center of the floating body with mooring lines, and a thruster provided at a front end or a rear end of the floating body. And a tension sensor for measuring the tension of a mooring line mooring both sides of the floating body, calculating means for determining the direction of action of an external force applied to the floating body from the tension measured by the tension sensor, and an external force determined by the calculating means And a driving means for driving each of the thrusters such that the direction of action of the floating body is parallel to the floating body.

According to a fourth aspect of the present invention, there is provided a floating body mooring device for mooring a floating body offshore, wherein mooring means for mooring both sides near the center of the floating body with mooring lines, and a mooring line laterally attached to a rear end of the floating body. And a winch for lifting and unreeling the mooring line to move the rear end of the floating body to the side, a tension sensor for measuring the tension of the mooring line mooring both sides of the floating body, and a tension measured by the tension sensor. And a driving means for driving the winch such that the direction of action of the external force determined by the calculating means is parallel to the floating body.

According to a fifth aspect of the present invention, there is provided a floating body mooring device for mooring a floating body offshore, comprising: mooring means for mooring both sides near the center of the floating body with mooring lines; A winch for moving the trailing end of the floating body to the side by winding and unwinding the mooring line between the mooring line and the roller attached via a tensioner, and a tension sensor for measuring the tension of the mooring line mooring both sides of the floating body. Calculating means for determining the direction of action of an external force applied to the floating body from the tension measured by the tension sensor;
And a drive unit for driving the winch so that the direction of action of the external force obtained by the calculation unit and the floating body are parallel to each other.

According to a sixth aspect of the present invention, as the arithmetic means in the first to fifth aspects, the mooring upper end position of the mooring line is calculated from the measured value of the tension sensor, and the center of gravity of the floating body is obtained from the calculated value. A calculation means is provided for detecting the direction in which the center of gravity has moved as the direction of action of the external force.

According to a seventh aspect of the present invention, there is provided a floating body mooring device for mooring a floating body offshore, wherein the mooring line is moored along the left and right sides near the front end and near the rear end of the floating body with mooring lines having different characteristics at the front end near the rear end. Means, a thruster provided at a rear end of the floating body, and a wave height / wave direction meter in front of the floating body,
A wind / wind direction sensor, a sensor such as a tidal current meter, and a measurement unit that wirelessly transmits a measurement signal to the floating body side, and a measurement unit that is provided on the floating body and receives a measurement signal transmitted from the measurement unit. The present invention is characterized in that it comprises a calculating means for determining the direction of action of the external force applied to the floating body, and a driving means for driving the thruster so that the direction of action of the external force determined by the calculating means is parallel to the floating body.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a schematic configuration diagram of a floating body mooring device according to a first embodiment of the present invention. As shown in FIG. 1, mooring lines 5 and 6 are provided on both sides of the hull 1 near the bow.
In addition, a relatively firm mooring is performed by an anchor (not shown) and the like, and a relatively loose mooring is performed on the stern by a mooring line 7 and an anchor (not shown) from behind.
That is, when an external force such as a tidal current, a wave, or a wind is applied to the hull 1, the stern side can move sideways as indicated by the arrow a according to the external force. When the hull 1 is moored, the direction in which an external force is generated is checked in advance for each installation sea area, and the hull 1 is moored so that the bow is directed in a direction in which the external force is likely to be generated. Then, tension sensors 11 and 12 such as load cells are installed on the mooring lines 5 and 6, respectively, and the tension applied to the left and right mooring lines 5 and 6 is measured.

A thruster 1 is provided at the stern of the hull 1.
3 and a driving device 14 such as a motor for driving the thruster 13 is provided. The thruster 13 can be turned in any direction in a horizontal plane. Then, the signals measured by the tension sensors 11 and 12 are input to the control device 15, and the drive of the drive device 14 is controlled by a command output from the control device 15. The control device 15 includes an arithmetic processing device such as a CPU, calculates the action direction of an external force applied to the hull 1 from the tension measured by the left and right tension sensors 11 and 12, and controls the thruster 13 based on the calculation result. The hull 1 is driven to control the hull 1 in the direction in which the external force acts.

Next, the operation of the control device 15 in the above embodiment will be described with reference to the flowchart shown in FIG. For example, when external forces such as tidal currents, waves, and wind are not acting on the hull 1 or are acting directly from the front, the tensions measured by the left and right tension sensors 11 and 12 are substantially balanced. The control device 15 controls the tension sensors 11, 1
2 is constantly checked to determine whether the right and left balance is maintained, that is, whether or not the external force is acting from an oblique direction or a lateral direction (step A1). If the external force is not acting obliquely or laterally, the determination operation is continued without operating the thruster 13.

When an external force such as a tide, a wave, or a wind acts on the hull 1 from an oblique direction or a lateral direction, and the balance of the tension measured by the tension sensors 11 and 12 is lost, the control device 15 The positions of the upper ends of the mooring lines 5 and 6 are calculated (step A2), and the position of the center of gravity G of the hull 1 is estimated from the calculated values and stored sequentially (step A).
3). Further, the control device 15 recognizes the direction in which the center of gravity G has moved as the acting direction of the external force, and controls the thruster 1 via the driving device 14 so that the hull 1 is parallel to the acting direction.
3 is operated to quickly move the stern in the left-right direction as shown by the arrow a (step A4). Thereafter, it is determined whether or not the tensions measured by the tension sensors 11 and 12 are balanced (step A5). If the tension is not balanced, the process returns to step A4 and the thruster 13 is continuously driven.
When the measured values of the tension sensors 11 and 12 are balanced by the driving of the thruster 13, it is determined that the hull 1 has become parallel to the direction of action of the external force, and the driving of the thruster 13 is stopped (step A6). Thereafter, the process returns to step A1, and the above-described processing is repeatedly executed.

As described above, the direction in which the external force acts is detected based on the measured values of the tension sensors 11 and 12, and the thruster 13 is driven based on the detected information to move the stern of the hull 1 so that the hull 1 1 can be quickly moved in parallel with the direction of action of the external force, so that the hull 1 can be moved in the direction of the external force, that is, the operation of the weather vane can be performed quickly and reliably, and excessive tension is applied to the mooring line. Therefore, it is possible to prevent a breakage accident.

In the first embodiment, the thruster 1
3 shows the case where the stern of the hull 1 is moved in the left-right direction as shown by the arrow a, but after the hull 1 is moved in parallel with the direction of action of the external force, the external force from the front is further applied to the tension sensor 11, It is also possible to control the position of the hull 1 so that the thrusters 13 are driven so that the hull 1 moves forward as measured by 12 and the measurement values of the tension sensors 11 and 12 are minimized. With this configuration, the hull 1
Can be kept more stable, and the tension applied to the mooring line can be further reduced. In this case, the above-mentioned object can be achieved by one thruster 13, but thrusters for advancing the hull 1 may be provided separately and independently.

In the first embodiment, the case where the measured values of the tension sensors 11 and 12 provided on the mooring lines 5 and 6 are input to the control device 15 is described. A sensor such as a wave direction meter, a wind / wind direction meter, a tide meter, or the like may be provided in front of the hull 1, and the measurement signal may be wirelessly input to the control device 15 and controlled by the signal.

(Second Embodiment) Next, a second embodiment of the present invention will be described. FIG. 3 is a configuration diagram of a floating mooring device according to a second embodiment of the present invention. In the second embodiment, instead of the thruster 13, a mooring line 21 and a winch 22 for winding and unwinding the mooring line 21 are provided.
Is provided. The mooring line 21 is provided in the lateral direction near the stern of the hull 1 and its tip is fixed by an anchor or the like. The winch 22 is provided in the control device 1.
The stern of the hull 1 is moved to the side as shown by the arrow a by being driven through the drive device 14 by the command from 5 and winding up and extending the mooring line 21.

In the second embodiment, when an external force is generated, the winch 22 is driven instead of the thruster 13 to wind up and extend the mooring line 21 so that the hull 1 is parallel to the direction in which the external force acts. The control method is the same as that of the first embodiment, and the same effect as that of the first embodiment can be obtained.

(Third Embodiment) Next, a third embodiment of the present invention will be described. FIG. 4 is a configuration diagram of a floating body mooring device according to a third embodiment of the present invention. In the third embodiment, both sides near the center of the hull 1 are moored relatively firmly by the mooring lines 5 and 6, and a thruster 13a is provided at the stern and a thruster 13b is also provided at the bow side. The thrusters 13a and 13b can be turned in any direction in a horizontal plane. Also, the thrusters 13a,
13b is driven via the driving devices 14a and 14b in accordance with a command from the control device 15 as in the first embodiment.

In the third embodiment, when an external force is generated, the control device 15 determines the direction in which the external force acts in the same manner as in the first embodiment, and drives the hull 1 so as to be parallel to the acting direction. The thrusters 13a, 1a, 1
Activate 3b. In this case, both the bow and the stern move in the directions of the arrows a and b with the center of the hull 1 as a base point, so that the hull 1 becomes parallel to the direction of action of the external force.

In the third embodiment, when the hull 1 makes a pitch motion in waves, if the hull is moored near the bow, the vertical movement of the mooring portion increases. By fixing the vicinity, an excessive tension of the mooring line due to the pitch motion can be reduced. Further, in the third embodiment, since the rigid mooring point with less swinging is located at the center of the hull 1, for example, no excessive force is applied to the connecting portion such as a pipe, and the swinging is wide at the center of the hull. Work space can be reduced. The thruster may be on either the stern side or the bow side.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described. FIG. 5 is a configuration diagram of a floating mooring device according to a fourth embodiment of the present invention. The fourth embodiment is different from the third embodiment in that the thrusters 13a and 13b
In place of the mooring line 21 on the stern side of the hull 1 and a winch 2 for winding and unwinding the mooring line 21.
2 is provided. The tip of the mooring line 21 is fixed by an anchor or the like. In this case, the mooring line 21 is provided diagonally left and right behind the stern,
By interposing rollers 23a and 23b on both sides of the winch 22, the winch 22 is held linearly at the winch 22 portion. That is, by holding the mooring line 21 linearly for a fixed length, the winch 22 allows the mooring line 21 to be reliably wound up and extended. The winch 22 is driven and controlled via the driving device 14 according to a command from the control device 15 as in the first embodiment.

In the fourth embodiment, when an external force is generated in the same manner as in the second embodiment shown in FIG. 3, the winch 2 is driven via the drive unit 14 by a command from the control unit 15.
By driving the mooring line 21 and raising and extending the mooring line 21, the hull 1 is made parallel to the direction in which the external force acts, and the same effect as in the third embodiment can be obtained.

In the fourth embodiment, the mooring line 21 is provided diagonally behind the stern and the mooring line 7 on the stern side is provided.
Is shown, but the mooring line 21 may be provided in the lateral direction as in the second embodiment shown in FIG.

Also, in the second to fourth embodiments, reference numeral 1 is used as described in the first embodiment shown in FIG.
A sensor such as a wave height / wave direction meter, a wind / wind direction meter, and a tide meter shown in FIG. 6 may be provided in front of the hull 1 and a measurement signal thereof may be wirelessly input to the control device 15 and controlled by the signal. good.

In each of the above embodiments, the case where the hull 1 is moored has been described. However, other types of floating structures such as floating oil production / storage / loading systems, coastal structures, disaster prevention purges, etc. Applicable.

[0034]

As described above in detail, according to the present invention, both the left and right sides near the front end and the vicinity of the rear end of the floating body are moored by mooring lines having different characteristics at the front end and near the rear end. A thruster is provided, and the tension of the mooring line is detected by a tension sensor, the direction of action of the external force is detected from the detection signal, the thruster is driven, and the floating body is quickly moved in parallel with the direction of action of the external force. In addition, the operation of the weather vane can be performed quickly and reliably, an excessive tension is not applied to the mooring line, and a breakage accident can be prevented.

A mooring line and a winch are provided in place of the thruster. The direction of action of the external force is detected from the output value of the tension sensor, and the mooring line is wound up and extended by the winch, and the floating body is quickly moved to the direction of the external force. Since they are moved in parallel, the same effect as in the case where the thrusters are provided can be obtained.

Further, according to the present invention, the center portion of the floating body is moored by mooring lines on both left and right sides, and thrusters are provided at both the front end and the rear end of the floating body to detect the direction of action of the external force from the detection signal of the tension sensor. To drive the thruster,
The floating body is moved quickly in parallel with the direction of external force, so even if the floating body makes a pitch motion in the waves, it does not apply excessive tension to the mooring line due to the effect, preventing the accident of breaking. be able to.

Further, according to the present invention, the center portion and the front end portion of the floating body are moored by mooring lines having different characteristics, the mooring line and the winch are provided at the rear end of the floating body, and the direction of action of the external force is detected from the detection signal of the tension sensor. And drive the winch,
Since the floating body is quickly moved in parallel with the direction of action of the external force, the same effect as when the thrusters are provided at both the front end and the rear end of the floating body can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a floating mooring device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the control device in the embodiment.

FIG. 3 is a configuration diagram of a floating mooring device according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a floating body mooring device according to a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a floating mooring device according to a fourth embodiment of the present invention.

FIG. 6 is a configuration diagram showing a conventional swivel type single point mooring system.

FIG. 7 is a configuration diagram showing a conventional simplified mooring system.

[Explanation of symbols]

 Reference Signs List 1 hull 2 turret 3 mooring line 5, 6, 7 mooring line 11.12 tension sensor 13, 13a, 13b thruster 14, 14a, 14b drive device 15 control device 21 mooring line 22 winch 23a, 23b roller

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Nobuyoshi Tanigaki 5-717-1, Fukahori-cho, Nagasaki-city, Nagasaki Pref. No.1 F-term in Nagasaki Laboratory, Mitsubishi Heavy Industries, Ltd. (reference) 2D059 BB11 BB15

Claims (7)

[Claims] 1. A floating body mooring device for mooring a floating body offshore, comprising: mooring means for mooring the floating body near the front end, on the left and right sides, and near the rear end, with mooring lines having different characteristics where the front end is harder than the rear end. A thruster provided at the rear end of the floating body, a tension sensor for measuring the tension of a mooring line mooring the left and right sides near the front end of the floating body, and a direction of action of an external force applied to the floating body from the tension measured by the tension sensor And a driving means for driving the thruster so that the direction of action of the external force determined by the calculating means is parallel to the floating body. 2. A floating body mooring apparatus for mooring a floating body offshore, comprising: mooring means for mooring the floating body near the front end, on the left and right sides, and near the rear end, with mooring lines having different characteristics where the front end is harder than the rear end. A mooring line laterally attached to the rear end of the floating body, a winch for moving the rear end of the floating body to the side by rolling up and feeding out the mooring line, and a tension of a mooring line for mooring the left and right sides near the front end of the floating body. A tension sensor that measures the direction of action of the external force applied to the floating body from the tension measured by the tension sensor, and the action direction of the external force determined by the calculation means is parallel to the floating body. A floating body mooring device, comprising: driving means for driving a winch. 3. A floating body mooring device for mooring a floating body offshore, comprising: mooring means for mooring both sides near the center of the floating body with a mooring line; a thruster provided at a front end or a rear end of the floating body; A tension sensor that measures the tension of the mooring line mooring both sides of the floating body; a calculating unit that determines the direction of action of the external force applied to the floating body from the tension measured by the tension sensor; and a direction of action of the external force that is determined by the calculating unit. Drive means for driving each of the thrusters so that the floating bodies are parallel to each other. 4. A floating body mooring apparatus for mooring a floating body offshore, comprising: mooring means for mooring both sides near the center of the floating body with mooring lines; a mooring line laterally attached to a rear end of the floating body; A winch for moving the trailing end of the floating body to the side by rolling and unwinding, a tension sensor for measuring a tension of a mooring line mooring both sides of the floating body, and a tension applied to the floating body from the tension measured by the tension sensor. A floating body mooring device, comprising: arithmetic means for determining the direction of action of an external force; and drive means for driving the winch such that the direction of action of the external force determined by the arithmetic means is parallel to the floating body. 5. A floating body mooring device for mooring a floating body offshore, comprising: mooring means for mooring both sides near the center of the floating body with a mooring line; A winch for moving the trailing end of the floating body to the side by winding and unwinding the mooring line between the mooring line and the roller; a tension sensor for measuring the tension of a mooring line mooring both sides of the floating body; and the tension sensor. Computing means for determining the direction of action of the external force applied to the floating body from the tension measured by the above, and driving means for driving the winch such that the direction of action of the external force determined by the computing means is parallel to the floating body. A floating mooring device characterized by the above-mentioned. 6. The calculating means calculates a mooring upper end position of the mooring line from a measurement value of the tension sensor, obtains a position of a center of gravity of the floating body from the calculated value, and determines a direction in which the center of gravity moves to a direction in which an external force acts. The floating body mooring device according to claim 1, 2, 3, 4, or 5, wherein the detection is performed as: 7. A floating body mooring device for mooring a floating body offshore, comprising: mooring means for mooring the floating body near its front end, on the left and right sides and near its rear end, with mooring lines having different characteristics where the front end is harder than the rear end. A thruster provided at the rear end of the floating body, and a sensor such as a wave height / direction meter, a wind / wind direction meter, a tide meter, etc. provided in front of the floating body, and a measurement signal wirelessly transmitted to the floating body side. Means, provided on the floating body, calculating means for receiving a measurement signal transmitted from the measuring means to determine the acting direction of the external force applied to the floating body, and the acting direction of the external force determined by the calculating means and the floating body And a driving means for driving the thruster so as to be parallel to each other.