Semi-recovery type double-curvature sleeper device for preventing unfavorable deformation and vortex-induced vibration

Abstract

The invention discloses a semi-recovery type double-curvature sleeper device capable of preventing unfavorable deformation and vortex-induced vibration. A double-curvature sleeper base is a right-angled trapezoid prismatic table with a double-curvature slope, and the right-angled slope is attached to a seabed; the double-curvature inclined plane is vertically upward; the top triggering device is hinged to the higher end of the double-curvature inclined face of the double-curvature sleeper base. The lateral triggering force is used for controlling the submarine pipeline to move towards the lower end of the double-curvature sleeper base when the submarine pipeline is bent; the arc-shaped transition limiter is arranged on a seabed, one side of the arc-shaped transition limiter is connected with the lower end face of the double-curvature inclined plane of the double-curvature sleeper base, and the other side of the arc-shaped transition limiter is in lap joint with the end warping plate unit; the end warping plate unit comprises a warping plate spring assembly and a curve warping plate, one end of the warping plate spring assembly is fixed to the seabed, and the other end of the warping plate spring assembly is fixedly connected with the bottom face of the curve warping plate. According to the method, the investment amount is low, the stability of the pipeline can be maintained, and the sleeper base part can be recycled.

Description

Technical Field

[0001] The invention relates to the field of submarine pipeline integral buckling protection methods and equipment, and in particular to a semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration. Background Art

[0002] Submarine pipelines are key equipment in deep-sea oil and gas projects, and a large number of scholars have conducted a series of studies on their failure forms. The overall buckling of submarine pipelines is one of the main forms of pipeline failure. Uncontrollable horizontal buckling will cause the bending moment and stress in the curved section of the pipeline to accumulate continuously with the increase of temperature. After reaching the yield stress, the pipeline will undergo local buckling, fracture, fatigue and other failure modes, causing oil and gas leakage. Therefore, in order to reduce and prevent uncontrollable buckling of submarine pipelines, buckling prevention and control measures are needed.

[0003] The method of artificial intervention to induce pipeline buckling at a specific location is economical and effective. Commonly used construction methods in engineering include serpentine laying method, sleeper method and distributed buoyancy method. Among them, the sleeper method has good economic benefits and high buckling triggering rate, which makes the sleeper method widely used in engineering. The sleeper method causes the overall buckling of the pipeline by raising the pipeline to form an initial defect and forming a cantilevered section to reduce the soil resistance of the seabed to the pipeline.

[0004] The study found that increasing the height of the sleepers can effectively reduce the critical buckling load for the horizontal overall buckling of the pipeline, increase the positive displacement amplitude of the pipeline and promote the release of the axial force. However, excessive sleeper height will increase the risk of vortex-induced vibration and vertical buckling failure of the pipeline span under environmental loads or operational loads, leading to fatigue failure of the pipeline. In addition, the pipeline will undergo multiple opening and closing cycles during its service. During the repeated movement of the submarine pipeline, the soil on the side of the pipe will continue to accumulate, and the side soil resistance will increase with the increase in the number of cycles, thereby reducing the fatigue life of the pipeline.

[0005] When the pipeline is laid in shallow waters with large wave heights, wave force is considered the main environmental load that affects the stability of the submarine pipeline. Under the action of waves, the stability of the submarine pipeline is related to multiple factors such as the weight of the pipeline, environmental loads, and the resistance generated by the submarine soil. If the resistance provided by the submarine foundation soil is not enough to balance the wave force, the pipeline will slide out of its original position and become unstable in place. To prevent the pipeline from becoming unstable, it is necessary to increase the underwater weight of the pipeline, or adopt fixing measures such as anchoring and briquetting, or open a trench on the seabed for layout. However, all of the above measures will increase the amount of investment. Summary of the invention

[0006] In order to solve the problems in the prior art, the present invention proposes a semi-recyclable hyperbolic sleeper device with low investment, capable of maintaining pipeline stability, and capable of recycling the sleeper base portion to prevent adverse deformation and vortex-induced vibration.

[0007] To this end, the present invention adopts the following technical solutions:

[0008] A semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration comprises: a hyperbolic sleeper base, an arc-shaped transition limiter, an end seesaw unit and a top trigger device, wherein:

[0009] The hyperbolic sleeper base is arranged on the seabed and is a right-angled trapezoidal prism with a hyperbolic inclined surface, wherein the hyperbolic inclined surface faces away from the seabed;

[0010] The top trigger device is hinged to the higher end of the hyperbolic inclined surface of the hyperbolic sleeper base, and is used to provide a lateral trigger force for the submarine pipeline placed thereon; the lateral trigger force is used to control the submarine pipeline to move toward the lower end of the hyperbolic sleeper base when the pipeline buckles;

[0011] The arc-shaped transition stopper is fixedly arranged on the seabed, one side of which is connected to the lower end face of the hyperbolic slope of the hyperbolic sleeper base, and the other side of which is overlapped with the end seesaw unit;

[0012] The end seesaw unit comprises a seesaw spring assembly and a curved seesaw, wherein the lower end of the seesaw spring assembly is fixed to the seabed, and the upper end is fixedly connected to the bottom surface of the curved seesaw; under the action of the seesaw spring assembly, the higher end of the curved seesaw is lifted up and overlapped with the arc-shaped transition limiter; the lower end of the curved seesaw is in contact with the seabed;

[0013] The arc-shaped transition limiter is provided with an arc-shaped limit groove on one side facing the end rocker unit, and the arc-shaped limit groove is used to limit the movement range of the submarine pipeline caused by buckling under the action of the end rocker unit.

[0014] Preferably, the hyperbolic bevel of the hyperbolic sleeper base has two different slopes, the slope of the higher portion is larger, and the slope of the lower portion is smaller; the two slope segments are connected by a circular arc curve.

[0015] Preferably, the lower end of the hyperbolic sleeper base is wider than the higher end, so as to avoid fracture and deformation caused by stress concentration when the submarine pipeline shrinks.

[0016] Preferably, the hyperbolic inclined surface is an arc-shaped surface with a convex middle portion, which is used to reduce the friction between the hyperbolic sleeper base and the submarine pipeline.

[0017] Preferably, the top trigger device comprises a horizontal plate, a vertical plate, a spring assembly, a limit rod assembly, a limit portion and a hinged portion, wherein:

[0018] The vertical plate is hinged to the higher end of the hyperbolic sleeper base through a hinge fixed near its bottom, so as to provide a lateral trigger force for the submarine pipeline placed on the horizontal plate; the horizontal plate is horizontally mounted on the hyperbolic sleeper base, close to one end of the vertical plate, through the spring assembly, so as to bear the submarine pipeline; the limit rod assembly and the limit part are symmetrically arranged on both sides of the hyperbolic sleeper base, one end of the single-sided limit rod assembly is hinged to the side of the horizontal plate, and the other end passes through the hollow limit part and then bends and extends to the side of the vertical plate away from the submarine pipeline, and the limit rod assembly is used to limit the inclination amplitude of the vertical plate; the distance between the hinge point of the horizontal plate and the edge of the horizontal plate close to the vertical plate is less than or equal to 0.3 times to 0.5 times the diameter of the submarine pipeline

[0019] Preferably, the higher end of the hyperbolic sleeper base is arranged as a plane to expand the range of movement of the vertical board.

[0020] Preferably, the arc-shaped transition limiter is detachably connected to the hyperbolic sleeper base.

[0021] Preferably, the horizontal board is 0.3m-1.5m wide and 0.5m-5.0m long; the vertical board is 0.3m-2.0m wide and 0.2m-3.0m long.

[0022] Preferably, the arc-shaped transition limiter is 2m-4m wide, and the diameter of the arc-shaped limit groove is 0.35-0.4m; the curved seesaw is 0.4m-1.1m long and 1m-2m wide.

[0023] Preferably, the total length of the hyperbolic sleeper base is 0.7m-6m, the higher end of the base is 0.6m-1.6m high and 1m-2m wide; the higher part of the hyperbolic slope has an inclination angle of 10°-50° and a length of 0.2m-2.0m; the lower part of the hyperbolic slope has an inclination angle of 2°-30° and a length of 0.5m-4.0m.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The higher section of the hyperbolic slide plate of the hyperbolic sleeper base of the present invention has a larger slope, which provides an initial lateral sliding force for the sliding of the submarine pipeline, prompting the pipeline to be closer to the seabed side when overall buckling occurs, reducing the height of the pipeline in the buckled section, and avoiding the risk of vortex-induced vibration and vertical buckling of the pipeline; the lower section of the hyperbolic slide plate of the hyperbolic sleeper base has a smaller slope, which ensures that the pipeline is close to the seabed while avoiding uncontrollable sliding caused by excessive sliding speed.

[0026] 2. The end seesaw unit of the present invention can achieve the purpose of avoiding pipeline periodic fatigue and reducing the total friction resistance of the pipeline by limiting the position of the submarine pipeline, ensuring that the pipeline only undergoes large displacement along the direction of the sleepers under the reciprocating action of the opening and closing loads.

[0027] 3. The arc-shaped transition limiter of the present invention can limit the vertical displacement of the pipeline and prevent the pipeline from vertically buckling under the action of temperature and pressure loads.

[0028] 4. The hyperbolic sleeper base of the present invention gradually widens as the height decreases, thereby increasing the contact area between the sleeper and the pipeline and avoiding stress concentration that causes pipeline damage; the hyperbolic sleeper base can be separated from other structures to achieve the recovery and recycling of the hyperbolic sleeper base, reducing the engineering application cost of the sleeper. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a side view perspective diagram of the present invention;

[0030] Figure 2 It is a schematic diagram of the front view of the present invention;

[0031] Figure 3 It is a schematic diagram of the arc curve structure on the hyperbolic inclined plane of the present invention;

[0032] Figure 4 It is a schematic diagram of the structure of the top trigger device of the present invention;

[0033] Figure 5 It is a schematic diagram of the use process of the top trigger device structure of the present invention at a certain moment;

[0034] Figure 6 It is a schematic diagram of the use process of the top trigger device structure of the present invention at a certain moment;

[0035] Figure 7 It is a schematic diagram of the structure of the end seesaw unit of the present invention;

[0036] Figure 8 A schematic diagram of the use process of the present invention from a frontal perspective;

[0037] Fig. 9 It is a schematic diagram of the positional relationship between the present invention and the submarine pipeline when it is first heated and pressurized to produce buckling;

[0038] Fig.10 It is a schematic diagram of the positional relationship between the present invention and the submarine pipeline when buckling occurs due to temperature and pressure reduction;

[0039] Fig.11 It is a schematic diagram of the positional relationship between the present invention and the submarine pipeline when buckling occurs due to temperature and pressure increase.

[0040] In the figure: 1. Hyperbolic sleeper base, 2. Arc transition limiter, 3. End rocker unit, 4. Top trigger device,

[0041] 301. seesaw spring assembly, 302. curved seesaw, 401. horizontal plate, 402. vertical plate, 403. spring assembly, 404. limit rod assembly, 405. limit part, 406. hinged part, a. submarine pipeline, b. seabed. DETAILED DESCRIPTION

[0042] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0043] like Figure 1 and Figure 2 As shown, the semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration of the present invention comprises: a hyperbolic sleeper base 1, an arc-shaped transition limiter 2, an end seesaw unit 3 and a top trigger device 4, wherein:

[0044] The hyperbolic sleeper base 1 is a right-angled trapezoidal prism with a hyperbolic inclined surface, and the inclined surface forming a right angle is attached to the seabed; the hyperbolic inclined surface faces the direction away from the seabed.

[0045] The top trigger device 4 is hinged to the higher end of the hyperbolic slope of the hyperbolic sleeper base 1, and is used to provide a lateral trigger force for the submarine pipeline placed thereon; the lateral trigger force is used to control the submarine pipeline to move toward the lower end of the hyperbolic sleeper base 1 when the pipeline is bent.

[0046] The arc-shaped transition stopper 2 is fixedly arranged on the seabed, one side of which is connected to the lower end face of the hyperbolic slope of the hyperbolic sleeper base 1, and the other side is overlapped with the end seesaw unit 3. An arc-shaped limit groove is arranged on the side of the arc-shaped transition stopper 2 facing the end seesaw unit 3, and the arc-shaped limit groove is used to limit the movement range of the submarine pipeline caused by the pipeline buckling under the action of the end seesaw unit 3, and can also prevent the pipeline from buckling vertically under the action of temperature and pressure loads.

[0047] like Figure 3 As shown, the hyperbolic bevel of the hyperbolic sleeper base 1 has two different slopes, the higher part has a larger slope, and the lower part has a smaller slope. The two slope sections are connected by a circular arc curve, the radius of the circular arc curve is greater than or equal to the radius of the submarine pipeline, and the slope is set to increase the probability of horizontal buckling of the submarine pipeline. The lower end of the hyperbolic sleeper base 1 is wider than the higher end, which is used to avoid a large stress concentration phenomenon on the submarine pipeline, resulting in local fracture and deformation. The surface of the hyperbolic bevel is an arc-shaped surface with a higher middle part and lower sides, and the arc-shaped surface is used to reduce the friction between the hyperbolic sleeper base 1 and the pipeline.

[0048] like Figure 4As shown, the top trigger device 4 includes a horizontal plate 401, a vertical plate 402, a spring assembly 403, a limit rod assembly 404, a limit portion 405 and a hinge portion 406, wherein:

[0049] The horizontal plate 401 is connected to the spring on the higher side of the hyperbolic inclined surface of the hyperbolic sleeper base 1 through the spring assembly 403, and the horizontal plate 401 is used to carry the submarine pipeline; the vertical plate 402 is hinged to the higher end of the hyperbolic sleeper base 1, and is used to provide lateral triggering force for the submarine pipeline placed on the horizontal plate 401, and the vertical plate 402 is hinged to the hyperbolic sleeper base 1 through a hinge part 406 fixedly arranged near its bottom.

[0050] The limit rod assembly 404 and the limit part 405 are symmetrically arranged on both sides of the hyperbolic sleeper base 1. One end of the single-sided limit rod assembly 404 is hinged to the side of the horizontal plate 401, and the other end passes through the hollow limit part 405 and bends and extends to the side of the vertical plate 402 away from the submarine pipeline; the top of the side of the hyperbolic sleeper base 1 close to the vertical plate 402 is a plane, which is used to increase the vertical plate 402 to obtain a larger range of motion after the limit part is released. The distance between the hinge point of the horizontal plate and the edge of the horizontal plate close to the vertical plate is less than or equal to 0.3 times to 0.5 times the diameter of the submarine pipeline.

[0051] like Figure 5 and Figure 6 As shown, when the submarine pipeline produces pipeline buckling, the submarine pipeline presses down the horizontal plate 401, and pushes the limit rod assembly 404 to make the vertical plate 402 break away from its limit. At this time, the vertical plate 402 provides a lateral trigger force toward the hyperbolic sleeper base 1 for the submarine pipeline through the part above its hinge point under the action of gravity.

[0052] like Figure 7 As shown, the end seesaw unit 3 includes a seesaw spring assembly 301 and a curved seesaw 302. One end of the seesaw spring assembly 301 is fixed to the seabed, and the other end is fixedly connected to the bottom surface of the curved seesaw 302. The higher end of the end seesaw unit 3 overlaps the arc transition limiter 2.

[0053] like Figure 8 As shown in FIG. 1 , when placing the submarine pipeline a on the horizontal plate 401 of the present invention, it is necessary to avoid the submarine pipeline from tilting and causing the horizontal plate 401 to move downward in advance; then, when the submarine pipeline a is running at high temperature and high pressure, an overall buckling trend will be generated. Under the action of the initial lateral trigger force and the hyperbolic sleeper base, the submarine pipeline a will undergo lateral overall buckling deformation, and the pipeline will slide along the curved seesaw to the seabed b, as shown in FIG. Fig. 9Then, when the submarine pipeline stops operating at high temperature and high pressure and then cools down, the deformation caused by the increase in temperature and pressure of the pipeline tends to decrease, and the pipeline slides along the curved plate to the end rocker unit, pressing down the rocker spring assembly and continuing to slide, and is finally restricted in the arc-shaped limit groove of the arc-shaped transition limiter, as shown in FIG. Fig.10 However, when the submarine pipeline is operated again at high temperature and high pressure, the pipeline slides out along the curved plate and slides to the seabed again, as shown in (I) to (III) in FIG. Fig.11 As shown in (Ⅰ) to (Ⅲ) in the figure.

[0054] This device prevents the submarine pipeline from large displacement under temperature and pressure cycle loads except for the first heating and pressure increase, avoiding cyclic fatigue of the pipeline during the reciprocating overall buckling process, stress accumulation leading to pipeline damage, and uncontrollable overall buckling of the pipeline under multi-directional movement; it also avoids vortex-induced vibration caused by the presence of sleepers, which may lead to pipeline damage. When the pipeline slides to the seabed, the double-curvature sleeper base and the top trigger device hinged to it can be removed and reused for pipeline sections at other locations.

[0055] Embodiment 1

[0056] The conventional pipeline used in this embodiment has a radius of 0.16195 m and a wall thickness of 0.0127 m. A double-curved sleeper device of the present invention is placed under each conventional pipeline with a spacing of 2000 m.

[0057] The total length of the hyperbolic sleeper base is 0.7m-6m, the higher end is 0.6m-1.6m high and 1m-2m wide; the higher part of the hyperbolic slope has an inclination angle of 10°-50° and a length of 0.2m-2.0m, and the lower part of the hyperbolic slope has an inclination angle of 2°-30° and a length of 0.5-4.0m.

[0058] In the top trigger device, the horizontal plate is 0.3-1.5m wide and 0.5m-5.0m long; the vertical plate is 0.3-2.0m wide and 0.2-3.0m long.

[0059] The arc transition limiter is 2m-4m wide, and the arc limit groove has a diameter of 0.35-0.4m. The curved seesaw of the end seesaw unit is 0.4-1.1m long, 1m-2m wide, and the seesaw spring assembly is 0.1m-1m high.

Claims

1. A semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration, characterized in that: include: A double-curved sleeper base (1), an arc-shaped transition limiter (2), an end rocker unit (3) and a top trigger device (4), wherein: The hyperbolic sleeper base (1) is arranged on the seabed and is a right-angled trapezoidal prism with a hyperbolic inclined surface, wherein the hyperbolic inclined surface faces away from the seabed; The top trigger device (4) is hinged to the higher end of the hyperbolic slope of the hyperbolic sleeper base (1) and is used to provide a lateral trigger force for the submarine pipeline placed thereon; The lateral trigger force is used to control the submarine pipeline to move toward the lower end of the double-curvature sleeper base (1) when the pipeline buckles; The arc-shaped transition stopper (2) is fixedly arranged on the seabed, one side of which is connected to the lower end surface of the hyperbolic inclined surface of the hyperbolic sleeper base (1), and the other side of which is overlapped with the end seesaw unit (3); The end seesaw unit (3) comprises a seesaw spring assembly (301) and a curved seesaw (302); the lower end of the seesaw spring assembly (301) is fixed to the seabed, and the upper end is fixedly connected to the bottom surface of the curved seesaw (302); under the action of the seesaw spring assembly (301), the higher end of the curved seesaw (302) is lifted up and overlapped with the arc-shaped transition limiter (2); the lower end of the curved seesaw (302) is in contact with the seabed; The arc-shaped transition limiter (2) is provided with an arc-shaped limit groove on one side facing the end rocker unit (3), and the arc-shaped limit groove is used to limit the movement range of the submarine pipeline caused by buckling under the action of the end rocker unit (3).

2. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 1 is characterized in that: The hyperbolic inclined surface of the hyperbolic sleeper base (1) has two different slopes, the slope of the higher part is larger, and the slope of the lower part is smaller; the two slope sections are connected by a circular arc curve.

3. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 1 is characterized in that: The lower end of the hyperbolic sleeper base (1) is wider than the higher end, so as to avoid fracture and deformation caused by stress concentration when the submarine pipeline contracts.

4. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 1 is characterized in that: The hyperbolic inclined surface is an arc-shaped surface with a convex middle, and is used to reduce the friction between the hyperbolic sleeper base (1) and the submarine pipeline.

5. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 1, characterized in that: The top trigger device (4) comprises a horizontal plate (401), a vertical plate (402), a spring assembly (403), a limit rod assembly (404), a limit portion (405) and a hinge portion (406), wherein: The vertical plate (402) is hinged to the higher end of the hyperbolic sleeper base (1) through a hinged portion (406) fixed near the bottom thereof, and is used to provide a lateral trigger force for the submarine pipeline placed on the horizontal plate (401); the horizontal plate (401) is horizontally installed on the hyperbolic sleeper base (1) through the spring assembly (403), at one end close to the vertical plate (402), and is used to support the submarine pipeline; the limit rod assembly (404) and the limit portion (405) are both symmetrically arranged on the horizontal plate (403). On both sides of the hyperbolic sleeper base (1), one end of a single-side limiting rod assembly (404) is hinged to the side of the horizontal plate (401), and the other end passes through a hollow limiting portion (405) and then bends and extends to a side of the vertical plate (402) away from the submarine pipeline. The limiting rod assembly (404) is used to limit the inclination range of the vertical plate (402); the distance between the hinge point of the horizontal plate (401) and the edge of the horizontal plate (401) close to the vertical plate (402) is less than or equal to 0.3 times to 0.5 times the diameter of the submarine pipeline.

6. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 5, characterized in that: The higher end of the hyperbolic sleeper base (1) is arranged as a plane, so as to expand the range of movement of the vertical board (402).

7. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 1, characterized in that: The arc-shaped transition stopper (2) is detachably connected to the hyperbolic sleeper base (1).

8. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 5, characterized in that: The horizontal plate (401) is 0.3m-1.5m wide and 0.5m-5.0m long; the vertical plate (402) is 0.3m-2.0m wide and 0.2m-3.0m long.

9. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 1, characterized in that: The arc-shaped transition limiter (2) is 2m-4m wide, and the diameter of the arc-shaped limit groove is 0.35-0.4m; the curved seesaw (302) is 0.4m-1.1m long and 1m-2m wide.

10. The semi-recoverable hyperbolic sleeper device for preventing adverse deformation and vortex-induced vibration according to claim 2, characterized in that: The total length of the hyperbolic sleeper base is 0.7m-6m, the higher end of which is 0.6m-1.6m high and 1m-2m wide; the higher part of the hyperbolic slope has an inclination angle of 10°-50° and a length of 0.2m-2.0m; the lower part of the hyperbolic slope has an inclination angle of 2°-30° and a length of 0.5m-4.0m.

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