KR101871250B1

KR101871250B1 - Apparatus and method for preventing damage of riser in spm system

Info

Publication number: KR101871250B1
Application number: KR1020170086100A
Authority: KR
Inventors: 김도엽; 이강수; 박병재; 김현석
Original assignee: 한국해양과학기술원
Priority date: 2017-07-06
Filing date: 2017-07-06
Publication date: 2018-06-27
Also published as: WO2019009566A1

Abstract

The present invention relates to an apparatus and method for preventing damage to a riser in a single point mooring (SPM) system. In particular, the present invention senses a manifold position of an SPM buoy and pipeline end manifold (PLEM) at both end units of the riser. Accordingly, the present invention controls a hexapod module capable of performing six degrees of freedom motion so that a bending radius of the riser is greater than the minimum bending radius while stress of the riser is not more than predetermined stress.

Description

[0001] APPARATUS AND METHOD FOR PREVENTING DAMAGE OF RISER IN SPM SYSTEM [0002]

The present invention relates to an apparatus and a method for preventing a riser from being damaged in a single point mooring (SPM) system. More particularly, the present invention relates to an apparatus and a method for detecting the position of a manifold of a SPM buoy and a pipeline end manifold To control a hexapod module capable of 6 degrees of freedom motion so that the bending radius of the riser is greater than the minimum bending radius and the stress of the riser is not more than the set stress, .

Normally, when a large oil tanker with a large draft is difficult to enter the port, the SPM system is installed in the offshore and the oil is transferred through a single mooring with the large tanker. Among the SPM systems, CALM (Catenary Anchor Leg Mooring) system, which applies suspension mooring, is generally used, and this CALM system maintains a standing position on the surface with 4 to 8 stranded mooring rope.

If the SPM buoy moves excessively due to the water changes and the marine environment such as winds and waves, excessive stress may be generated in the risers (vertical pipes and hoses that transport the oil products) connecting the bottom of the SPM buoy to the PLEM of the seabed And bending deformation below the minimum bend radius (MBR) may cause a problem in safety of the riser. Particularly, it is difficult to design a riser that can be stable at the highest altitude and the lowest altitude at the depth of the tide.

Korean Patent Registration No. 1511360 discloses a method for easily applying the oil or gas having the danger of explosion while satisfying harsh environmental conditions of the ocean such as waves, wind and sea water, A processing device for SPM is disclosed.

However, in the conventional processing apparatus for SPM, when the pressure difference between the end manifold and the riser unit is out of the set value, the flow of the fluid between the end manifold and the riser unit is cut off. Therefore, And there is a problem that it is not an improvement plan of the SPM system itself which must endure harsh environmental conditions of the ocean.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an SPM system capable of stably operating an SPM system by preventing damage to a riser in a harsh environment of the ocean, And an object of the present invention is to provide an apparatus and method for preventing damage.

In order to achieve the above object, an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention includes a PLM (Pipeline end manifold) fixed to the sea bed, an SPM A single point mooring buoy, and a riser for connecting the PLEM with the SPM to allow fluid to flow therethrough, the apparatus comprising: a fixed plate fixed to a seabed, An upper plate mounted on an upper portion of the stationary plate, a hexaphod module capable of moving six degrees of freedom to connect the stationary plate and the upper plate, and a manifold mounted on the upper plate to connect the riser and the pipeline from the ground ; A motion sensing unit installed at both ends of the riser for sensing a position of the SPM buoy and the manifold; The stress and bending radius of the riser are calculated using the positions of the SPM buoy and the manifold sensed by the motion sensing unit, and the stress of the riser becomes a set stress or less, and the bending radius of the riser becomes the minimum bending radius (MBR: Minimum Bend Radius) of the HexaPod module; And a hexapod module driving unit configured to receive a control signal from the control unit and perform switching operation to control the driving of the hexapod module.

In the apparatus for preventing damage to the riser in the SPM system according to the above embodiment, the pipeline and the manifold may be connected by a flexure hose.

In an apparatus for preventing damage to a riser in an SPM system according to the above-described embodiment, one end of the pipeline may be formed with a L-shape spool piece.

In the apparatus for preventing damage to a riser in an SPM system according to the above embodiment, the motion sensing unit may include a first motion sensing unit installed at an upper end of the riser to sense a position of the SPM buoy, And a second motion sensing unit installed to sense the position of the manifold.

In an apparatus for preventing damage to a riser in an SPM system according to the above embodiment, the Hexaphod module is composed of four or six multiple cylinders, and the position of the upper plate is determined by extension and compression of each of the plural cylinders Can be changed.

In the apparatus for preventing damage to the riser in the SPM system according to the above embodiment, the plurality of cylinder ends may be formed of rotatable joints such as ball bearings to further facilitate the 6-degree-of-freedom movement of the upper plate.

According to another aspect of the present invention, there is provided a method of preventing damage to a riser in an SPM system, comprising: sensing a position of an SPM buoy and a manifold by a motion sensing unit; Calculating a stress and a bending radius of the riser by using a position of the SPM buoy and the manifold sensed by the motion sensing unit; And the controller controls the Hexaphod module so that the stress of the riser becomes a set stress or less and the bend radius of the riser is larger than a minimum bend radius (MBR).

According to the apparatus and method for preventing the damage of the riser in the SPM system according to the embodiment of the present invention, the stress and the bend radius of the riser are calculated using the positions of the SPM buoy and the manifold sensed by the motion sensing unit, By controlling the Hexaphod module so that the stress is below the set stress and the bend radius of the riser is greater than the Minimum Bend Radius (MBR), movement of the manifold of the PLEM causes the damage of the riser The SPM system can be operated stably.

1 is a schematic perspective view of an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention.
2 is a side view of an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention.
3 is a detailed circuit diagram of an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention.
4 is a flowchart illustrating a damage prevention method of a riser implemented by an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic perspective view of an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention. FIG. 2 is a side view of an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention. 3 is a detailed circuit diagram of an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention.

First, an SPM (Single Point Mooring) system applied to an embodiment of the present invention will be described. 1 and 2, the SPM system includes a PLM (Pipeline end manifold) 30 fixed to the undersea, an SPM buoy 10 floated on the sea with an anchoring position determined by the PLEM 30, And a riser 20 for connecting the SPM 20 and the SPM 20 to allow the fluid to flow.

The PLEM 30 includes a fixed plate 36 fixed to the seabed by an anchor pile P, an upper plate 34 mounted on top of the fixed plate 36, a fixed plate 36, A Hexapod module 38 capable of six degrees of freedom motion (X-axis, Y-axis, Z-axis, pitch, roll, yaw) And a manifold 32 mounted on an upper surface of the riser 34 to connect the riser 20 with the pipeline 40 from the ground.

The hexafod module 38 is composed of four or six plural cylinders, and serves to change the position of the top plate 34 by stretching and compressing each of the plural cylinders. The multiple cylinder ends are constructed of rotatable joints, such as ball bearings, to further facilitate the implementation of six degrees of freedom movement of the top plate 34.

The pipeline 40 and the manifold 32 are connected by the flexure hose 50 so that the pipeline 40 is connected to the upper plate 34 which is stationary but is interlocked by six degrees of freedom movement of the hexapod module 38 ). One end of the pipeline 40 is formed with a spoolpiece 40a so that the pipeline 40 installed on the seabed and the manifold 32 installed on the upper surface of the upper plate 34 can be easily connected do.

Hereinafter, an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention will be described with reference to the drawings.

1 to 3, the apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention includes a motion sensing unit 100, a controller 200, and a hashed module driver 300 And wireless communication is possible between these components.

The motion sensing unit 100 is installed at both ends A of the riser 20 and senses the positions of the SPM buoy 10 and the manifold 32. A motion sensor such as a gyro sensor or an infrared sensor is used . The motion sensing unit 100 includes a first motion sensing unit 110 installed at an upper end of the riser 20 to sense the position of the SPM buoy 10 and a second motion sensing unit 110 installed at a lower end of the riser 20, And a second motion sensing unit 120 that senses the position of the second motion sensor.

The controller 200 calculates the stress and the bending radius of the riser 20 using the positions of the SPM buoy 10 and the manifold 32 sensed by the motion sensing unit 100. When the stress of the riser 20 And outputs a signal to the hexapod module driving unit H to control the hexaphod module 38 such that the bending radius of the riser 20 is larger than the minimum bend radius (MBR) And a microcomputer can be used. The installation position of the control unit 200 may be the PLEM 30 or the SPM buoy 10 and is not particularly limited.

The hexapod module driving unit 300 receives a control signal from the control unit 200 and performs a switching operation to control the driving of the hexapod module H. [

A method for preventing damage to a riser using an apparatus for preventing damage to a riser in an SPM system according to an embodiment of the present invention will be described.

FIG. 4 is a flow chart for explaining a damage prevention method of a riser implemented by an apparatus for preventing a damage to a riser in an SPM system according to an embodiment of the present invention, wherein S represents a step.

First, the position of the SPM buoy 10 and the manifold 32 is sensed by the motion sensing unit 100 (S10).

The control unit 200 receives the sensing signal from the motion sensing unit 100 and calculates the stress and bending radius of the riser 20 using the sensed SPM buoy 10 and the position of the manifold 32 S20).

The controller 200 determines that the stress of the riser 20 calculated in step S20 is equal to or lower than the set stress and that the bending radius of the riser 20 is larger than the minimum bend radius MBR And controls the pod module 38 (S30). The movement of the upper plate 34 and the movement of the manifold 32 are adjusted.

According to the apparatus and method for preventing the damage of the riser in the SPM system according to the embodiment of the present invention configured as described above, the stress and bending radius of the riser are measured using the positions of the SPM buoy and the manifold sensed by the motion sensing unit The Hexafod module is controlled so that the bending radius of the riser is greater than the Minimum Bend Radius (MBR) by moving the manifold of the PLEM so that the stress of the riser becomes less than the set stress, The SPM system can be operated stably by preventing damage to the riser.

Although the best mode has been shown and described in the drawings and specification, certain terminology has been used for the purpose of describing the embodiments of the invention and is not intended to be limiting or to limit the scope of the invention described in the claims. It is not. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments may be made without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: SPM Buoy
20: riser
30: PLEM
32: Manifold
34: upper plate
36: Fixed plate
38: hexapod module
40: Pipeline
40a: Spool piece
50: Flexible hose
A: Mounting position of motion detection part
100: Motion detection unit
110: first motion detection unit
120: second motion sensing unit
200:
300: Hexafod module driver
H: Hexafod module

Claims

A PLM (Pipeline end manifold) fixed to the undersea, a SPM (Single Point Mooring) part suspended by the PLEM at an anchoring position, and a riser connecting the PLEM and the SPM part to allow fluid to flow therethrough , A device for preventing damage to the riser in an SPM system, comprising:
The PLEM includes a fixed plate fixed to the seabed, an upper plate mounted on the fixed plate, a hexaphod module capable of moving in six degrees of freedom to connect the fixed plate and the upper plate, And a manifold connecting the pipeline from the ground;
A motion sensing unit installed at both ends of the riser for sensing a position of the SPM buoy and the manifold;
The stress and bending radius of the riser are calculated using the positions of the SPM buoy and the manifold sensed by the motion sensing unit, and the stress of the riser becomes a set stress or less, and the bending radius of the riser becomes the minimum bending radius (MBR: Minimum Bend Radius) of the HexaPod module; And
And a hexapod module driving unit configured to receive a control signal from the control unit and to be switched so as to control the driving of the hexapod module.

The method according to claim 1,
Wherein the pipeline and the manifold are connected by a flexure hose.

The method according to claim 1,
Wherein one end of the pipeline is formed with a plied spool piece.

The method according to claim 1,
The motion sensing unit
A first motion sensing unit installed at an upper end of the riser for sensing a position of the SPM buoy,
And a second motion sensing unit installed at a lower end of the riser to sense the position of the manifold.

The method according to claim 1,
Wherein the Hexaphod module is comprised of four or six multiple cylinders and changes the position of the top plate by extension and compression of each of the plurality of cylinders.

6. The method of claim 5,
Wherein the plurality of cylinder ends are comprised of rotatable joints to further facilitate the 6-degree of freedom movement of the top plate.

A method for preventing damage to a riser using an apparatus for preventing damage to the riser in the SPM system according to claim 1,
Sensing the position of the SPM buoy and the manifold by the motion sensing unit;
Calculating a stress and a bending radius of the riser by using a position of the SPM buoy and the manifold sensed by the motion sensing unit; And
Wherein the controller controls the Hexaphod module so that the stress of the riser is less than a set stress and the bend radius of the riser is greater than a minimum bend radius (MBR) / RTI >

8. The method of claim 7,
The motion sensing unit
A first motion sensing unit installed at an upper end of the riser for sensing a position of the SPM buoy,
And a second motion sensing unit installed at a lower end of the riser to sense the position of the manifold.

8. The method of claim 7,
Wherein the Hexaphod module is comprised of four or six multiple cylinders and varies the position of the top plate by stretching and compressing each of the plurality of cylinders.

10. The method of claim 9,
Wherein the plurality of cylinder ends are comprised of rotatable joints to facilitate implementation of six degrees of freedom movement of the top plate.