Design method of helicopter mooring seat

Abstract

The application relates to the field of ship technology, in particular to a design method of a helicopter mooring seat, which comprises the following steps: S1, analyzing the material mechanics performance of a conventional mooring seat structure to obtain a replaceable new material; S2, optimizing the mooring seat structure, designing a spherical disc as a hollow column model, thickening a panel model to a set thickness, spacing four openings on the panel model, making the middle part of the panel model a cross shape, and assembling the panel model and the hollow column model to form a mooring seat model; S3, checking the strength of the mooring seat model and optimizing the mooring seat model; S4, manufacturing a hollow column and a panel based on the optimized mooring seat model, welding the panel on the hollow column, and forming a mooring seat body at the opening of the hollow column; and S5, carrying out a breaking test and a tension test on the mooring seat body. The application can reduce the manufacturing difficulty and the manufacturing cost, and meets the needs of being equipped on a ship.

Description

Technical Field

[0001] This invention relates to the field of marine technology, and in particular to a method for designing a mooring seat for a helicopter. Background Technology

[0002] A certain experimental vessel is equipped with a mooring system for securing helicopters. The mooring seat, a key component of commonly used mooring systems, requires careful design, fabrication, and installation considering various complex factors such as the ship's rolling, wave impact, and the aircraft's weight and inertia. Currently, the main type of mooring seat used domestically is the male cross-shaped type, consisting of a seat body and a cover plate. The seat body includes a ball plate with a welded panel at its opening. The ball plate of the seat body has a bowl-shaped structure, demanding high processing standards and requiring mold production. It also has high load-bearing requirements and a product inspection testing process, resulting in a relatively high unit price and a long procurement cycle.

[0003] With the increasing deployment of helicopters on ships, ship development requires parking areas with extensive mooring seats. The demand for mooring seats is substantial, and procurement cannot meet the construction plans and cost requirements of these parking areas. One experimental ship, with four parking areas, requires approximately 300 mooring seats. Following conventional procurement procedures would significantly impact the construction of the hull structure. Furthermore, the mooring seats are made of 907A or 921A high-strength steel. 907A high-strength steel is a special steel plate, difficult to procure and costly, making it unsuitable for mass production.

[0004] Therefore, a helicopter tethered seat design method is needed to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a design method for a helicopter mooring seat that can reduce manufacturing difficulty and cost, and meet the needs of shipboard equipment.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] The design method for helicopter tie-down seats includes the following steps:

[0008] S1. Analyze the mechanical properties of conventional tethered seat structures to identify new materials that can be used as replacements;

[0009] S2. Optimize the tethering seat structure by designing the sphere as a hollow column model and thickening the panel model to a set thickness. Four openings are spaced apart on the panel model so that the middle part of the panel model is cross-shaped. Assemble the panel model and the hollow column model to form the tethering seat model.

[0010] S3. Perform strength verification on the tethered seat model and optimize the tethered seat model;

[0011] S4. Using the optimized mooring seat model, manufacture a hollow column and a panel, weld the panel onto the hollow column, and form the mooring seat body at the opening of the hollow column;

[0012] S5. Conduct a fracture test and a tensile test on the tethered seat body.

[0013] In some embodiments, in step S1, the material mechanical properties include the material yield strength, tensile strength, and impact resistance.

[0014] In some embodiments, in step S2, rounded chamfers are designed at the corners of the four openings of the panel model.

[0015] In some embodiments, in step S3, a set tensile load is applied to the cross-shaped structure of the panel model at three different angles to obtain the maximum force value, and compared with the standard allowable value to determine whether the design requirements are met.

[0016] In some embodiments, in step S4, the hollow column includes a cylinder and a base plate. The base plate is welded to the end of the cylinder away from the panel, and the base plate is located in the cylinder. The lower end face of the base plate is flush with the end face of the cylinder.

[0017] In some embodiments, a first welding bevel is formed at the lower end face edge of the base plate, and welding is performed along the circumference of the base plate at the first welding bevel and at the intersection of the upper end face of the base plate and the cylinder.

[0018] In some embodiments, in step S4, a second welding bevel is formed at the outer edge of the opening of the hollow column, and the hollow column is welded to the panel at the second welding bevel along the circumference of the hollow column.

[0019] In some embodiments, in step S5, a breaking load is applied to the cross-shaped structure of the panel and the breaking test is performed for a set time, and a tensile load is applied to the cross-shaped structure of the panel and the tensile test is performed for a set time.

[0020] In some embodiments, step S6 is further included: welding the mooring seat body to the deck of the hull and conducting a load test.

[0021] In some embodiments, in step S6, it is necessary to first weld a butt plate to the outer peripheral surface of the panel of the mooring seat body, and the butt plate is welded to the deck.

[0022] The beneficial effects of this invention are:

[0023] This invention provides a helicopter tethered seat design method. It analyzes the material mechanical properties of conventional tethered seat structures to obtain replaceable new materials, optimizes the tethered seat structure, designs the spherical disk as a hollow column model, and thickens the panel model to a predetermined thickness. Four openings are spaced apart on the panel model, making the center of the panel model cross-shaped. The panel model and the hollow column model are assembled to form the tethered seat model. The tethered seat model undergoes strength verification and optimization. The hollow column and panel are manufactured using the optimized tethered seat model. The panel is welded to the hollow column, located at the opening of the hollow column, to form the tethered seat body. The tethered seat body undergoes fracture and tensile tests. By using a new material with similar mechanical properties as a replacement, and modeling based on the mechanical properties of this new material, the original spherical disk structure is optimized into a hollow column model. The panel model is thickened and assembled to form the tethered seat model. The use of a hollow column model reduces the difficulty of subsequent manufacturing, and the thickening of the panel model improves the strength of the subsequently manufactured panel. By performing strength verification on the mooring seat model, it can be further optimized to ensure that the subsequently manufactured mooring seats meet the requirements. After the mooring seat body is manufactured, fracture tests and tensile tests are conducted to verify the structural strength of the mooring seat body. Using the above methods reduces manufacturing difficulty and costs, thus meeting the needs of shipboard equipment. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0025] Figure 1 This is a flowchart of a helicopter tethered seat design method according to the present invention;

[0026] Figure 2 This is a partial cross-sectional view of the tethered seat body in a helicopter tethered seat design method of the present invention;

[0027] Figure 3 This is a top view of the tethered seat body in a helicopter tethered seat design method of the present invention.

[0028] In the picture:

[0029] 1. Tie-in seat body; 11. Cylinder body; 12. Base plate; 13. Panel; 131. Opening; 2. Connecting plate. Detailed Implementation

[0030] Before explaining any implementation of this application in detail, it should be understood that this application is not limited to its application to the structural details and component arrangements set forth in the following description or shown in the above drawings.

[0031] In this application, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0032] In this application, the terms "connection," "combination," "coupling," and "installation" can refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without the need for an intermediary, while an indirect connection refers to two parts or components each being connected to at least one intermediary, with the connection achieved through the intermediary. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.

[0033] In this application, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0034] In this application, the directional terms "upper," "lower," "left," "right," "front," and "rear" are used to describe the orientation and positional relationships shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when an element is mentioned as being connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, and rear side not only represent positive orientation but can also be understood as lateral orientation. For example, "below" can include directly below, lower left, lower right, lower front, and lower rear.

[0035] In the design and manufacture of mooring seats, in order to reduce manufacturing difficulty and cost while meeting the needs of shipboard equipment, such as... Figures 1-3 As shown, this invention provides a method for designing a helicopter tethered seat. The method includes the following steps:

[0036] S1. Analyze the mechanical properties of conventional tethered seat structures to identify new materials that can be used as replacements;

[0037] S2. Optimize the tethering seat structure, design the sphere as a hollow column model, and thicken the panel model to the set thickness. Four openings 131 are opened at intervals on the panel model so that the middle part of the panel model is cross-shaped. Assemble the panel model and the hollow column model to form the tethering seat model.

[0038] S3. Perform strength verification on the tethered seat model and optimize the tethered seat model;

[0039] S4. Using the optimized tethering seat model, manufacture a hollow column and a panel 13, weld the panel 13 onto the hollow column, and position it at the opening of the hollow column to form the tethering seat body 1.

[0040] S5. Conduct a fracture test and a tensile test on the tie seat body 1.

[0041] By replacing the original spherical disc structure with a new material possessing similar mechanical properties, and modeling based on these properties, the original structure was optimized into a hollow column model. The panel model was then thickened and assembled to form the mooring seat model. The use of a hollow column model reduced the difficulty of subsequent manufacturing, while thickening the panel model improved the strength of the subsequently manufactured panel 13. Strength verification of the mooring seat model allowed for further optimization, ensuring that the manufactured mooring seat met requirements. After the mooring seat body 1 was manufactured, fracture tests and tensile tests were conducted to verify its structural strength. This approach reduced manufacturing difficulty and costs, meeting the needs of shipboard equipment.

[0042] In some embodiments, in step S1, the material mechanical properties include yield strength, tensile strength, and impact resistance. The overall performance of a material can be comprehensively reflected by analyzing its yield strength, tensile strength, and impact resistance. In this embodiment, the prior art uses 907A steel. In terms of yield strength, tensile strength, and impact resistance, DH36 steel is similar to 907A. Therefore, DH36 can be selected as the material for load-bearing components when manufacturing mooring seats. This eliminates the need to use special 907A steel for design and construction.

[0043] In some embodiments, in step S2, rounded chamfers are designed at the corners of the four openings 131 of the panel model. This design avoids stress concentration at the corners, thus improving the mechanical properties of the panel model.

[0044] In some embodiments, in step S3, a set tensile load is applied to the cross-shaped structure of the panel model at three different angles to obtain the maximum force value, and compared with the standard allowable value to determine whether the design requirements are met. In this embodiment, the angle between the force direction of the mooring seat model and the plane is not less than 35°, the tensile force is not less than 137.2kN, and the failure load is not less than 210kN. The calculated load is a tensile force of 210kN applied at the center of the cross intersection of the panel model, and the tensile conditions in three directions of 35°, 45°, and 90° are used as verification. The equivalent stress cloud diagram and shear stress cloud diagram under each working condition are obtained through finite element analysis. The maximum calculated force value of the stress cloud diagram and shear stress cloud diagram is extracted and compared with the standard allowable value to obtain the calculated stress result under each working condition. By comparing with the standard allowable value, it is determined whether the design requirements are met. If the requirements are not met, the mooring seat model is thickened to improve its strength.

[0045] In some embodiments, in step S4, the hollow column includes a cylinder 11 and a base plate 12. The base plate 12 is welded to the end of the cylinder 11 away from the panel 13, and the base plate 12 is located inside the cylinder 11. The lower end face of the base plate 12 is flush with the end face of the cylinder 11. By manufacturing the mooring seat body 1 in the above manner, the base plate 12 can be avoided from occupying additional space, thereby facilitating subsequent installation on the deck of the ship.

[0046] In some embodiments, a first welding bevel is formed at the lower end edge of the base plate 12, and welding is performed along the circumference of the base plate 12 at the first welding bevel and at the intersection of the upper end surface of the base plate 12 and the cylinder 11. This welding method ensures a stable connection between the base plate 12 and the cylinder 11.

[0047] In some embodiments, in step S4, a second welding bevel is formed at the outer edge of the opening of the hollow column, and the hollow column is welded to the panel 13 at the second welding bevel along the circumference of the hollow column. This method ensures a stable connection between the hollow column and the panel 13.

[0048] In some embodiments, in step S5, a breaking load is applied to the cross-shaped structure of panel 13 for a set time to conduct a breaking test, and a tensile load is applied to the cross-shaped structure of panel 13 for a set time to conduct a tensile test. An electronic universal testing machine is used. The rated load is applied to the tie-down body 1 through the machine's hook and held for 1 minute. The tie-down body 1 shows no damage. The rated load of the testing machine is selected based on the tie-down breaking load of 210 kN. The same test procedure is followed for a tensile test of 137.2 kN on the tie-down body 1, and the tie-down body 1 shows no deformation.

[0049] In some embodiments, step S6 is further included: welding the mooring seat body 1 to the deck of the hull and conducting a load test. The correctness and integrity of the installation of the new mooring seat body 1 are checked. Five mooring seat bodies 1 are randomly selected from each of the shutdown areas for load testing. The mooring seat bodies 1 are connected using a mooring rigging to simulate the interface, and a vertical tensile force T (171.5 kN) is applied to the mooring seat body 1 for a duration of not less than 30 seconds. After the tensile load test, the appearance of the mooring seat body 1 and the weld of the butt joint structure are observed, and the inspection results are all qualified.

[0050] In some embodiments, in step S6, a butt plate 2 needs to be welded to the outer peripheral surface of the panel 13 of the mooring seat body 1, and the butt plate 2 is welded to the deck. By setting the butt plate 2, a stable connection between the mooring seat body 1 and the deck can be ensured, reducing the difficulty of welding.

[0051] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for designing a tie-down seat for a helicopter, characterized in that, Includes the following steps: S1. Analyze the mechanical properties of conventional tethered seat structures to identify new materials that can be used as replacements; S2. Optimize the tethering seat structure by designing the sphere as a hollow column model and thickening the panel model to a set thickness. Four openings (131) are opened at intervals on the panel model so that the middle part of the panel model is cross-shaped. Assemble the panel model and the hollow column model to form a tethering seat model. S3. Perform strength verification on the mooring seat model and optimize the mooring seat model. Apply a set tensile load to the cross-shaped structure of the panel model at three different angles to obtain the maximum force value, and compare it with the standard allowable value to determine whether the design requirements are met. S4. A hollow column and a panel (13) are manufactured using the optimized mooring seat model. The panel (13) is welded onto the hollow column and forms the mooring seat body (1) at the opening of the hollow column. The hollow column includes a cylinder (11) and a base plate (12). The base plate (12) is welded to the end of the cylinder (11) away from the panel (13), and the base plate (12) is located in the cylinder (11). The lower end face of the base plate (12) is flush with the end face of the cylinder (11). A first welding bevel is opened at the edge of the lower end face of the base plate (12). Welding is performed along the circumference of the base plate (12) at the first welding bevel of the base plate (12) and at the intersection of the upper end face of the base plate (12) and the cylinder (11). S5. Perform a fracture test and a tensile test on the tether body (1).

2. The helicopter tie-down seat design method according to claim 1, characterized in that, In step S1, the mechanical properties of the material include the material yield strength, tensile strength, and impact resistance.

3. The helicopter tie-down seat design method according to claim 1, characterized in that, In step S2, rounded chamfers are designed at the corners of the four openings (131) of the panel model.

4. The helicopter tie-down seat design method according to claim 1, characterized in that, In step S4, a second welding bevel is opened at the outer edge of the opening of the hollow column, and the hollow column is welded to the panel (13) at the second welding bevel along the circumference of the hollow column.

5. The helicopter tie-down seat design method according to claim 1, characterized in that, In step S5, a fracture test is performed by applying a set breaking load to the cross-shaped structure of the panel (13) for a set duration, and a tensile test is performed by applying a set tensile load to the cross-shaped structure of the panel (13) for a set duration.

6. The helicopter tie-down seat design method according to claim 1, characterized in that, It also includes step S6, welding the mooring seat body (1) to the deck of the ship for a load test.

7. The helicopter tie-down seat design method according to claim 6, characterized in that, In step S6, it is necessary to first weld a butt plate (2) to the outer peripheral surface of the panel (13) of the mooring seat body (1), and the butt plate (2) is welded to the deck.

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