An inclined sleeper capable of controlling the buckling mode of a pipeline and its application
By designing an inclined sleeper device and using slide rails and sliders to control the buckling mode of the pipeline, the problems of low triggering success rate and anti-symmetric buckling of existing sleepers were solved. Symmetric buckling control and critical temperature reduction were achieved, thus improving the stability of deep-sea pipelines.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TIANJIN UNIV
- Filing Date
- 2022-08-03
- Publication Date
- 2026-07-03
AI Technical Summary
The existing sleeper has a low success rate in triggering buckling and often induces antisymmetric buckling, making the pipe more susceptible to damage. Improvements are needed to increase the success rate of triggering buckling and avoid antisymmetric buckling.
A tilted sleeper device is designed to apply a continuous thrust by setting a slide rail and a slider on the tilted sleeper base to control the buckling mode of the pipeline, ensuring symmetrical buckling. The magnitude of the thrust is changed by adjusting the tilt angle of the sleeper base and the weight of the slider, thereby reducing the critical buckling temperature.
It significantly improves the success rate of sleeper buckling triggering, reduces the critical buckling temperature of the pipeline, ensures symmetrical buckling, and reduces the risk of pipeline failure.
Smart Images
Figure CN117553170B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of methods and equipment for overall buckling protection of deep-sea pipelines, and more specifically to an inclined sleeper that can control the buckling mode of a pipeline and its application. Background Technology
[0002] Overall buckling of subsea pipelines is one of the main forms of deep-water pipeline failure and a crucial aspect of deep-water pipeline stability design. In response to this phenomenon, scholars have conducted research on buckling protection for subsea pipelines. Studies have found that compared to construction methods that completely eliminate overall buckling, such as trenching and burying or piling up rocks, the sleeper method is a relatively economical and efficient buckling protection scheme suitable for deep-sea pipelines. This method involves laying sleepers at intervals in areas with favorable routing conditions, artificially inducing a series of relatively small and controllable horizontal bucklings at the sleeper locations. This allows the accumulated axial force caused by high temperature and pressure to be shared by multiple buckling locations, preventing uncontrollable and large horizontal buckling deformation in one place and effectively preventing pipeline rupture due to severe deformation.
[0003] Research and application of railway sleepers in my country started relatively late. The Liuhua 16-2 project, which went into operation in 2020, was the first to use railway sleepers as a buckling protection device for pipelines. Currently, the railway sleepers used by the international academic and industrial communities are all large-diameter tubular supports with circular or square cross-sections. Engineering measurement data shows that the success rate of triggering buckling using existing railway sleepers is only about 80%, and the induced buckling mode is often antisymmetric buckling. However, in actual engineering, antisymmetric buckling should be avoided as much as possible because the strain within the pipe wall is usually higher when antisymmetric buckling deformation occurs than when symmetric modes occur, making the pipeline more prone to failure.
[0004] Therefore, the existing sleeper configurations that may trigger antisymmetric buckling must be improved. It is of engineering application value to propose a sleeper device that can avoid antisymmetric buckling of the pipeline, reduce the critical buckling temperature of the pipeline, and improve the buckling triggering success rate. Summary of the Invention
[0005] This invention overcomes the shortcomings of existing technologies. Existing sleeper-triggered buckling has a low success rate, and the induced buckling mode is often antisymmetric buckling. When the pipeline undergoes antisymmetric buckling deformation, the pipeline is more prone to failure. This invention provides an inclined sleeper that can control the pipeline buckling mode and its application. The inclined sleeper can apply a continuous thrust to the pipeline after the pipeline is activated, so that the pipeline buckling displacement is maximized at the point of thrust application, thereby ensuring that the pipeline undergoes a symmetric buckling mode. Moreover, the thrust can cause the pipeline to have an initial defect at the point of thrust application, thereby significantly reducing the critical buckling temperature of the pipeline and improving the success rate of sleeper buckling triggering.
[0006] The objective of this invention is achieved through the following technical solution.
[0007] An inclined sleeper capable of controlling the buckling modes of a pipeline includes an inclined sleeper base, a slide rail, a slider, and a baffle.
[0008] The inclined sleeper base adopts a right-angled trapezoidal structure with a rectangular lower surface and an arc-shaped upper surface. A slide rail mounting seat is formed in the middle of the upper surface of the inclined sleeper base, running from left to right through the base. The slide rail is mounted on the slide rail mounting seat, and the length of the slide rail is less than that of the slide rail mounting seat. A slider stop is provided at one end of the slide rail mounting seat. A slider limiting groove is formed between the slider stop and the slide rail in the slide rail mounting seat. Slots are evenly opened on the bottom surface of the slide rail. The slider is slidably mounted on the slide rail. There are two baffles, and the lower part of each baffle is inserted into the slot. The baffles are respectively installed at both ends of the slider to prevent the slider from sliding down the slide rail.
[0009] The acute angle between the upper surface of the inclined sleeper base and the horizontal direction is 0-10°.
[0010] The slide rail also adopts an inclined structure, and the inclination angle of the slide rail is the same as that of the inclined sleeper base.
[0011] The slider limiting groove is located at 3 / 4-5 / 6 of the total length of the inclined sleeper base.
[0012] The total length of the inclined sleeper base is 15-25m.
[0013] The average height of the inclined sleeper base is 0.8-1.5m.
[0014] The slide rail has a concave cross-section.
[0015] The slider has a T-shaped cross-section.
[0016] The lower part of the baffle also adopts a T-shaped structure that cooperates with the slide rail.
[0017] The application of the inclined sleepers in the overall buckling of submarine pipelines results in a 17%-53% reduction in the critical buckling temperature when the inclination angle of the inclined sleepers changes from 0.1° to 10° compared to existing sleepers.
[0018] The beneficial effects of the present invention are as follows: by placing a slider on the inclined sleeper base, the inclined sleeper can provide a stable and continuous thrust to the pipeline after it is opened. This thrust can form a horizontal initial defect at the sleeper, thereby controlling the deformation mode when the pipeline buckles and ensuring the occurrence of symmetrical buckling.
[0019] By adjusting the inclination angle of the sleeper base and the weight of the slider, the magnitude of the slider's thrust on the pipeline can be changed, thereby effectively reducing the critical buckling temperature of the pipeline and improving the success rate of sleeper buckling triggering.
[0020] The inclined sleeper, by excavating a slider limiting groove on the sleeper base, allows the slider to slide down the slide rail into the limiting groove after causing the pipeline to buckle symmetrically, making it easy to recycle. Attached Figure Description
[0021] Figure 1 This is a diagram showing the overall structural layout of the subsea pipeline and the present invention;
[0022] Figure 2 This is a schematic diagram of the overall structure of the present invention;
[0023] Figure 3 This is a top view of the structure of the present invention;
[0024] Figure 4 This is a partial enlarged view of the slide rail, slider, and baffle in this invention;
[0025] Figure 5 This is a schematic diagram of the cross-sectional structure of the present invention;
[0026] Figure 6 A comparison diagram of the pipe buckling mode calculation results between existing sleepers and the present invention;
[0027] Figure 7 A comparison chart of the pipe temperature-displacement amplitude calculation results between existing sleepers and the present invention;
[0028] Figure 8 This is a comparison chart of the calculation results of pipe temperature-displacement amplitude under different inclination angles according to the present invention;
[0029] In the diagram: 1 is the inclined sleeper base, 2 is the slider limiting groove, 3 is the slide rail, 4 is the slider, 5 is the baffle, and 6 is the slider stop.
[0030] For those skilled in the art, other related figures can be obtained from the above figures without any creative effort. Detailed Implementation
[0031] The technical solution of the present invention will be further described below through specific embodiments.
[0032] Example
[0033] An inclined sleeper capable of controlling the buckling mode of a pipeline includes an inclined sleeper base 1, a slide rail 3, a slider 4, and a baffle 5.
[0034] The inclined sleeper base 1 adopts a right-angled trapezoidal structure with a rectangular lower surface and a rounded upper surface. The rectangular lower surface ensures stable contact with the seabed, while the rounded upper surface ensures smooth contact with the pipeline, preventing excessive contact stress at sharp corners and potential damage to the pipeline over time. A slide rail mounting seat is formed in the middle of the upper surface of the inclined sleeper base 1, running from left to right through the base. The slide rail 3 is mounted on the slide rail mounting seat, and the length of the slide rail 3 is less than that of the slide rail mounting seat. A [feature / feature] is provided at one end of the slide rail mounting seat. A slider stop 6 is provided, and a slider limiting groove 2 is formed in the slide rail mounting seat between the slider stop 6 and the slide rail 3. This allows the slider 4 to slide down the slide rail 3 and enter the slider limiting groove 2 after causing the pipe to buckle symmetrically, which facilitates the recycling of the slider 4. Slots are evenly provided on the bottom surface of the slide rail 3. The slider 4 is slidably mounted on the slide rail 3. There are two baffles 5. The lower part of the baffles 5 is inserted into the slots. The baffles 5 are installed at both ends of the slider 4 to prevent the slider 4 from sliding down the slide rail 3.
[0035] The acute angle between the upper surface of the inclined sleeper base 1 and the horizontal direction is 0-10°.
[0036] The slide rail 3 also adopts an inclined structure, and the inclination angle of the slide rail 3 is the same as that of the inclined sleeper base 1.
[0037] The slider limiting groove 2 is located at 3 / 4-5 / 6 of the total length of the inclined sleeper base 1.
[0038] The total length of the inclined sleeper base 1 is 15-25m.
[0039] The average height of the inclined sleeper base 1 is 0.8-1.5m.
[0040] The slide rail 3 has a concave cross-section.
[0041] Slider 4 has a T-shaped cross-section.
[0042] The lower part of the baffle 5 also adopts a T-shaped structure that cooperates with the slide rail 3.
[0043] To further illustrate the content of this invention, the effects of this invention are verified using the finite element method in conjunction with the accompanying drawings:
[0044] The parameters for the example are as follows: the inclination angle of the inclined sleeper base 1 is 5°, and the volume of the slider 4 is 0.6m³. 3 The slider 4 has a mass of 4800 kg, the average height of the inclined sleeper base 1 is 1 m, the length of the inclined sleeper base 1 is 20 m, the slider limiting groove 2 is located at the 16 m position of the inclined sleeper base 1, and the pipeline is laid at the center of the inclined sleeper base 1. Figure 1 As shown, the specific pipes and modeling parameters are shown in Table 1:
[0045] Table 1 Calculation Parameters
[0046]
[0047]
[0048] The finite element simulation of the horizontal buckling process of the pipeline at the sleeper is as follows: First, the pipeline is laid on the inclined sleeper of this invention, and contacts the seabed under its own weight. A suspended section appears near the inclined sleeper of this invention, such as... Figure 1 As shown, the suspended section can be regarded as forming a vertical defect at the inclined sleeper support of the present invention, providing a precondition for pipe buckling; when the pipe is subjected to temperature to simulate the process of pipe opening, the pipe first undergoes vertical buckling at the inclined sleeper of the present invention under temperature load; as the temperature further increases, due to the smaller horizontal constraint, the vertical buckling is transformed into horizontal buckling.
[0049] Depend on Figure 6 It is known that, using existing sleepers under the aforementioned pipeline parameters, the pipeline experiences anti-symmetrical buckling, with two points of maximum buckling displacement, both located on the seabed. However, with the inclined sleepers of this invention, due to the continuous horizontal thrust exerted on the pipeline by the slider 4, a horizontally symmetrical initial defect is formed at the inclined sleepers of this invention, ultimately resulting in symmetrical buckling. The maximum displacement occurs at only one location, above the inclined sleepers of this invention. Figure 7 It can be seen that as the internal temperature of the pipeline increases, the horizontal displacement amplitude of the pipeline remains unchanged at first, and then due to the buckling of the pipeline, the horizontal displacement continues to increase with the temperature. The temperature corresponding to the inflection point of the horizontal displacement is the critical buckling temperature required for buckling to occur. Figure 6 The critical buckling temperature of the pipeline under the action of the inclined sleepers in this invention is 22°C, which is about 39% lower than the critical buckling temperature of 36°C under the action of existing sleepers.
[0050] Figure 8 This shows the variation of the maximum buckling displacement of the pipeline with temperature under different sleeper inclination angles θ. Figure 8 It is known that as the inclination angle of the sleeper increases, the critical buckling temperature of the pipeline decreases significantly. Compared with existing sleepers, when the inclination angle of the sleeper changes from 0.1° to 10°, the critical buckling temperature decreases by 17%-53%. The smaller the critical buckling temperature, the easier it is for the pipeline to buckle, that is, the greater the buckling triggering success rate of the sleeper. Therefore, the inclined sleeper of the present invention can control the direction and mode of pipeline buckling compared with existing sleepers, and significantly reduces the critical buckling temperature of the pipeline, greatly improving the buckling triggering success rate.
[0051] For ease of explanation, spatial relative terms such as “up,” “down,” “left,” and “right” are used in the embodiments to describe the relationship of one element or feature shown in the figures relative to another element or feature. It should be understood that, in addition to the orientations shown in the figures, spatial terms are intended to include different orientations of the device in use or operation. For example, if the device in the figures is inverted, an element described as being “down” of other elements or features would be positioned “up” of those other elements or features. Therefore, the exemplary term “down” can encompass both up and down orientations. The device may be positioned in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein can be interpreted accordingly. Moreover, relational terms such as “first” and “second” are used merely to distinguish one component from another that has the same name, and do not necessarily require or imply any such actual relationship or order between the components.
[0052] The present invention has been described in detail above, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.
Claims
1. An inclined sleeper capable of controlling the buckling mode of a pipeline, characterized in that: Includes inclined sleeper base, slide rail, slider and baffle, The inclined sleeper base adopts a right-angled trapezoidal structure with a rectangular lower surface and an arc-shaped upper surface. A slide rail mounting seat is formed in the middle of the upper surface of the inclined sleeper base, running from left to right through the inclined sleeper base. The slide rail is mounted on the slide rail mounting seat, and the length of the slide rail is less than that of the slide rail mounting seat. A slider stop is provided at one end of the slide rail mounting seat. A slider limiting groove is formed in the slide rail mounting seat between the slider stop and the slide rail. Slots are evenly opened on the bottom surface of the slide rail. The slider is slidably mounted on the slide rail. There are two baffles, and the lower part of the baffles is inserted into the slots. The baffles are respectively installed at the beginning and end of the slider.
2. The inclined sleeper with controllable pipe buckling mode according to claim 1, characterized in that: The acute angle between the upper surface of the inclined sleeper base and the horizontal direction is 0-10°.
3. The inclined sleeper with controllable pipe buckling mode according to claim 1, characterized in that: The slide rail also adopts an inclined structure, and the inclination angle of the slide rail is the same as that of the inclined sleeper base.
4. The inclined sleeper with controllable pipe buckling mode according to claim 1, characterized in that: The slider limiting groove is located at 3 / 4-5 / 6 of the total length of the inclined sleeper base.
5. The inclined sleeper with controllable pipe buckling mode according to claim 1, characterized in that: The total length of the inclined sleeper base is 15-25m.
6. The inclined sleeper with controllable pipe buckling mode according to claim 1, characterized in that: The average height of the inclined sleeper base is 0.8-1.5m.
7. The inclined sleeper with controllable pipe buckling mode according to claim 1, characterized in that: The slide rail has a concave cross-section, and the slider has a T-shaped cross-section.
8. The inclined sleeper with controllable pipe buckling mode according to claim 7, characterized in that: The lower part of the baffle also adopts a T-shaped structure that cooperates with the slide rail.
9. The application of the inclined sleeper with controllable buckling mode as described in any one of claims 1-8 in the overall buckling of subsea pipelines.
10. The application according to claim 9, characterized in that: Under the action of the inclined sleepers, compared with existing sleepers, when the inclination angle of the inclined sleepers changes from 0.1° to 10°, the critical buckling temperature is reduced by 17%-53%.