A method for optimizing the structural performance of offshore oil pipe cord layers

Abstract

The present invention discloses a method for optimizing the performance of the cord layer structure of an offshore oil pipe, comprising the following steps: S100, establishing a relationship between the ultimate bearing load of the offshore oil pipe and the cord layer structure parameters; S200, setting the parameters of the offshore oil pipe; S300, creating a hydrodynamic model of the offshore oil pipe according to the parameters of the offshore oil pipe, and obtaining the bending moment data and tension data of the offshore oil pipe; S400, comparing the bending moment data and tension data of the offshore oil pipe with the design allowable data of the offshore oil pipe respectively; S500, correcting the cord layer structure parameters according to the comparison results, and optimizing the performance of the cord layer structure of the offshore oil pipe. The present invention can optimize the performance of the cord layer structure of the offshore oil pipe, and the parameter design of the cord layer structure is combined with the hydraulic dynamic model, so that reasonable cord layer structure parameters of the offshore oil pipe can be easily designed, thereby improving the quality of the offshore oil pipe.

Description

Technical Field

[0001] The invention relates to the technical field of offshore oil pipe production design, in particular to a method for optimizing the structural performance of an offshore oil pipe cord layer. Background Art

[0002] Cord fabric mainly uses strong strands as warp and medium and fine single yarns as weft, so that the warp is arranged closely and the weft is arranged sparsely, resembling a curtain, so it is called cord fabric. Cord fabric is mainly used in the pipe wall of oil pipelines to enable it to withstand huge pressure, impact load and strong vibration.

[0003] The cord layer plays an important supporting and protective role in offshore oil pipelines. The ultimate bending moment and tension of the cord layer directly affect the stability and durability of the oil pipeline on the seabed. The oil pipeline may face the forces of the natural environment such as sea currents, wind and waves on the seabed, and the cord layer must be able to withstand these forces to maintain the stable position and structural integrity of the oil pipeline.

[0004] And in order to ensure operational safety, the setting of the ultimate bending moment and ultimate tension must take into account safety factors during operation. Excessive tension or bending moment may cause the rupture of the cord layer or deformation of the oil pipe, thereby increasing operational risks and maintenance costs.

[0005] The cord layer has a great influence on the ultimate bending moment and ultimate tension of offshore oil pipelines. How to improve the quality of offshore oil pipelines by optimizing the parameters of the cord layer is a problem that needs to be solved at present. Summary of the invention

[0006] The purpose of the present invention is to provide a method for optimizing the structural performance of an offshore oil pipe cord layer. The method can be used to conveniently design reasonable structural parameters of the offshore oil pipe cord layer to improve the quality of the offshore oil pipe.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0008] A method for optimizing the structural performance of an offshore oil pipe cord layer comprises the following steps:

[0009] S100, establishing a cord layer structure information model of an offshore oil pipeline, and obtaining a relationship between the ultimate bearing load of the offshore oil pipeline and the cord layer structure parameters;

[0010] S200, setting parameters of offshore oil pipeline;

[0011] S300, creating a hydrodynamic model of the offshore oil pipeline according to the parameters of the offshore oil pipeline, and obtaining bending moment data and tension data of the offshore oil pipeline through the hydrodynamic model;

[0012] S400, comparing the bending moment data and tension data of the offshore oil pipeline with the design allowable data of the offshore oil pipeline;

[0013] S500. According to the comparison results, the cord layer structure parameters are corrected to optimize the performance of the offshore oil pipe cord layer structure.

[0014] Furthermore, in step S100, the relationship between the ultimate bearing load and the cord layer structure parameter is as follows:

[0015]

[0016] Among them, P J is the ultimate bearing load of the offshore oil pipeline, D is the inner diameter of the offshore oil pipeline, F is the correction factor, C is the number of cord winding layers, K is the tensile strength of a single cord, m is the cord density, β is the cord winding angle, and L is the cord elongation.

[0017] Furthermore, in the step S200, the specific method for setting the parameters of the offshore oil pipeline is as follows: setting the winding angle β of the cord to 30°, setting the design allowable data of the ultimate bearing load, the design allowable value of the bending moment of the offshore oil pipeline, and the design allowable value of the tension of the offshore oil pipeline, substituting the winding angle β of the cord and the design allowable data of the ultimate bearing load into the relationship between the ultimate bearing load and the cord layer structure parameter, and calculating the number of cord winding layers C; setting the inner and outer diameters, wall thickness, and weight per unit length of the offshore oil pipeline;

[0018] Furthermore, in step S300, based on the inner and outer diameters, wall thickness, weight per unit length, design allowable data of the ultimate bearing load, cord winding angle β and number of cord winding layers C of the offshore oil pipeline, a hydrodynamic model of the offshore oil pipeline is created using the hydrodynamic software ORCAFLEX, and the bending moment data and tension data of the offshore oil pipeline are extracted from the hydrodynamic model.

[0019] Furthermore, in the step S500, according to the comparison result, the cord layer structure parameters are corrected, and the specific method for optimizing the performance of the offshore oil pipeline cord layer structure is as follows: when the bending moment data is less than the design allowable value of the bending moment, gradually reduce the number of cord winding layers in the design parameters of the cord layer structure and gradually increase the cord winding angle in the design parameters of the cord layer structure while keeping the ultimate bearing load unchanged, until the bending moment data is not less than the design allowable bending moment data; when the tension data is less than the design allowable bending moment data, continue to increase the cord winding angle in the design parameters of the cord layer structure until the tension data is not less than the design allowable bending moment data.

[0020] Furthermore, in step S100, the ultimate bearing load is the offshore wind and wave load under the preset oil delivery pressure of the offshore oil pipeline.

[0021] Furthermore, the preset oil delivery pressure of the offshore oil pipeline is 1.0-2.0 MPa.

[0022] The beneficial effects of the present invention are as follows: the present invention can easily optimize the performance of the offshore oil pipe cord layer structure, can conveniently design reasonable offshore oil pipe cord layer structure parameters, and the parameter design of the cord layer structure is combined with the hydraulic dynamic model, the designed cord layer structure parameters are more reasonable, thereby improving the quality of the offshore oil pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other without conflict.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper surface", "lower surface", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "forward", "reverse", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] like Figure 1 As shown, a method for optimizing the performance of the offshore oil pipe cord layer structure is for an offshore oil pipe containing a cord layer and having a pipe structure without spiral steel wires between the layers of the offshore oil pipe.

[0027] The present invention specifically comprises the following steps:

[0028] S100, establishing a cord layer structure information model of an offshore oil pipeline, and obtaining a relationship between the ultimate bearing load of the offshore oil pipeline and the cord layer structure parameters.

[0029] The relationship between the ultimate bearing load and the cord layer structural parameters is as follows:

[0030]

[0031] Among them, P Jis the ultimate bearing load of the offshore oil pipeline, D is the inner diameter of the offshore oil pipeline, F is the correction factor, C is the number of cord winding layers, K is the tensile strength of a single cord, m is the cord density, β is the cord winding angle, and L is the cord elongation.

[0032] The correction factor F is related to the outer diameter B and inner diameter D of the offshore oil pipeline. The specific value of the correction factor F is determined by the following relationship: F= .

[0033] The ultimate bearing load is the offshore wind and wave load under the preset oil delivery pressure of the offshore oil pipeline, and the preset oil delivery pressure of the offshore oil pipeline is 1.0-2.0MPa.

[0034] S200, Setting parameters of offshore oil pipeline

[0035] The design parameters of the cord layer structure are input, and the ultimate bearing load is calculated using the cord layer structure information model. In this embodiment, the specifications and performance of the cord are shown in Table 1.

[0036] Table 1 Specifications and properties of cord

[0037] Line density Wire diameter tensile strength Elongation Width 1000D 1.1mm 320N 20% 60cm

[0038] The specific method for setting the parameters of the offshore oil pipeline is as follows: set the cord winding angle β to 30°, set the design allowable data of the ultimate bearing load, the design allowable value of the bending moment of the offshore oil pipeline and the design allowable value of the tension of the offshore oil pipeline, substitute the cord winding angle β and the design allowable data of the ultimate bearing load into the relationship between the ultimate bearing load and the cord layer structure parameters, and calculate the number of cord winding layers C; set the inner and outer diameters, wall thickness, and weight per unit length of the offshore oil pipeline.

[0039] S300: creating a hydrodynamic model of the offshore oil pipeline according to the parameters of the offshore oil pipeline, and obtaining bending moment data and tension data of the offshore oil pipeline through the hydrodynamic model.

[0040] Specifically, based on the inner and outer diameters, wall thickness, weight per unit length, design allowable data of the ultimate bearing load, cord winding angle β and number of cord winding layers C of the offshore oil pipeline, the hydrodynamic model of the offshore oil pipeline was created using the hydrodynamic software ORCAFLEX, and the bending moment data and tension data of the offshore oil pipeline were extracted from the hydrodynamic model.

[0041] In the riser design of offshore oil pipelines, the commonly used riser analysis software is Orcaflex. The first version of Orcaflex is OrcaFlex 11.4b, which is mainly used to analyze the mechanical properties of offshore structures and simulate the installation process. Using the hydrodynamic software ORCAFLEX, a dynamic model in the marine environment was established to simulate the impact of offshore wind and waves. The main functions of OrcaFlex11.4b include: 1. Riser system analysis: mechanical analysis of the riser system, including the stress, deformation, fatigue, etc. of the riser. 2. Simulation analysis of the transportation, installation and decommissioning and removal process of offshore engineering equipment: simulate the transportation, installation and decommissioning and removal process of offshore engineering equipment to evaluate the safety and reliability of the equipment. 3. Mooring analysis: analyze the mechanical properties of the mooring system, including the tension and deformation of the mooring cable. 4. Pipe laying process analysis: simulate the pipe laying process and evaluate the stress and deformation of the pipeline. 5. Towing system analysis: analyze the mechanical properties of the towing system, including the tension and deformation of the towing cable. 6. Aquaculture Facility Analysis: Conduct mechanical analysis of aquaculture facilities to assess the safety and reliability of the facilities. 7. Cable-stayed bridge structures, floating bridges, national defense, marine renewable energy, submarine cable routing and seismic analysis: Conduct analysis of cable-stayed bridge structures, floating bridges, national defense, marine renewable energy, submarine cable routing and seismic analysis.

[0042] The specific method for extracting bending moment data and tension data of offshore oil pipeline is as follows: The present invention adopts OrcaFlex11.4b, opens OrcaFlex 11.4b, creates a dynamic model of offshore oil pipeline, and sets relevant load parameters according to the ultimate bearing load value. Click the Select Results button on the tool bar to enter the result analysis interface, and select the calculation results you want to extract in the Range Graph object column in the Results Type column.

[0043] For the tension data results of offshore oil pipelines, select SCR, click the show button in the upper right corner of the interface to view the distribution curve, and click the value button to view the tension data results of offshore oil pipelines.

[0044] The calculation and extraction of the bending moment data results of the offshore oil pipeline are the same as the above method and will not be described further.

[0045] S400. Compare the ultimate bending moment data and ultimate tension data of the offshore oil pipeline with the design allowable data of the offshore oil pipeline.

[0046] S500. According to the comparison results, the cord layer structure parameters are corrected to optimize the performance of the offshore oil pipe cord layer structure.

[0047] The specific method is as follows: when the bending moment data is less than the design allowable value of the bending moment, under the condition that the ultimate bearing load remains unchanged, the number of cord winding layers in the design parameters of the cord layer structure is gradually reduced and the cord winding angle in the design parameters of the cord layer structure is gradually increased until the bending moment data is not less than the design allowable bending moment data; when the tension data is less than the design allowable bending moment data, the cord winding angle in the design parameters of the cord layer structure is continued to be increased until the tension data is not less than the design allowable bending moment data.

[0048] While reducing the number of cord winding layers, the cord winding angle should be increased to ensure that the ultimate bearing load meets the design allowable data of the ultimate bearing load. On the premise of meeting the design allowable data of the ultimate bearing load, the number of cord winding layers should be adjusted so that the ultimate bending moment data is not less than the design allowable bending moment data.

[0049] Working principle: The cord structure layer is the main pressure-bearing layer of the hose, and its main performance characteristics are high strength, small elongation, and good bending performance. During the use of the hose, the cord is subjected to various stresses such as stretching, bending, and torsion. Therefore, it is not enough to have only good basic performance, and it must also have excellent dynamic mechanical properties. Therefore, the present invention uses the hydrodynamic software ORCAFLEX to establish a dynamic model under the marine environment to simulate the impact of offshore wind and waves. Under a dynamic environment, the offshore oil pipeline is placed in a working state of crude oil transportation, and the parameters of the cord structure layer are designed, and the obtained parameters are more reasonable. In the design parameters of the cord structure layer, the number of winding layers of the cord layer cannot be too few, otherwise it cannot meet the load pressure requirements, and it cannot be too many, otherwise it will affect the curvature of the offshore oil pipeline. The breaking strength is an important parameter of the polyester fiber of the cord. Fibers of different thicknesses have different breaking strengths, so low elongation is conducive to the stability of the structure. The present invention can be used to easily optimize the performance of the offshore oil pipe cord layer structure, and can conveniently design reasonable offshore oil pipe cord layer structure parameters to improve the quality of the offshore oil pipe.

[0050] In addition, those skilled in the art may combine and combine the different embodiments or examples and the features of the different embodiments or examples described in this specification without contradiction. Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for optimizing the structural performance of an offshore oil pipe cord layer, characterized in that: The following steps are involved: S100, establishing a cord layer structure information model of an offshore oil pipeline, and obtaining a relationship between the ultimate bearing load of the offshore oil pipeline and the cord layer structure parameters; In step S100, the relationship between the ultimate bearing load and the cord layer structure parameter is as follows: ； Among them, P J is the ultimate bearing load of the offshore oil pipeline, D is the inner diameter of the offshore oil pipeline, F is the correction factor, C is the number of cord winding layers, K is the tensile strength of a single cord, m is the cord density, β is the cord winding angle, and L is the cord elongation; S200, setting parameters of offshore oil pipeline; S300, creating a hydrodynamic model of the offshore oil pipeline according to the parameters of the offshore oil pipeline, and obtaining bending moment data and tension data of the offshore oil pipeline through the hydrodynamic model; S400, comparing the bending moment data and tension data of the offshore oil pipeline with the design allowable data of the offshore oil pipeline; S500, based on the comparison results, correct the cord layer structure parameters and optimize the performance of the offshore oil pipe cord layer structure: In step S500, according to the comparison result, the parameters of the cord layer structure are corrected, and the specific method for optimizing the performance of the cord layer structure of the offshore oil pipeline is as follows: when the bending moment data is less than the design allowable value of the bending moment, the number of cord winding layers in the design parameters of the cord layer structure is gradually reduced and the cord winding angle in the design parameters of the cord layer structure is gradually increased while the ultimate bearing load remains unchanged, until the bending moment data is not less than the design allowable bending moment data; When the tension data is less than the design allowable bending moment data, continue to increase the cord winding angle in the design parameters of the cord layer structure until the tension data is not less than the design allowable bending moment data.

2. The method for optimizing the structure performance of offshore oil pipe cord layer according to claim 1, characterized in that: In step S200, the specific method for setting the parameters of the offshore oil pipeline is as follows: setting the winding angle β of the cord to 30°, setting the design allowable data of the ultimate bearing load, the design allowable value of the bending moment of the offshore oil pipeline, and the design allowable value of the tension of the offshore oil pipeline, substituting the winding angle β of the cord and the design allowable data of the ultimate bearing load into the relationship between the ultimate bearing load and the cord layer structure parameter, and calculating the number of cord winding layers C; setting the inner and outer diameters, wall thickness, and weight per unit length of the offshore oil pipeline.

3. The method for optimizing the structure performance of offshore oil pipe cord layer according to claim 2, characterized in that: In step S300, a hydrodynamic model of the offshore oil pipeline is created using the hydrodynamic software ORCAFLEX according to the inner and outer diameters, wall thickness, weight per unit length, design allowable data of the ultimate bearing load, the cord winding angle β and the number of cord winding layers C of the offshore oil pipeline, and the bending moment data and tension data of the offshore oil pipeline are extracted from the hydrodynamic model.

4. The method for optimizing the structure performance of offshore oil pipe cord layer according to claim 1, characterized in that: In step S100, the ultimate bearing load is the offshore wind and wave load under the preset oil delivery pressure of the offshore oil pipeline.

5. The method for optimizing the structure performance of offshore oil pipe cord layer according to claim 1, characterized in that: The preset oil delivery pressure of the offshore oil pipeline is 1.0-2.0MPa.

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