Method for optimizing the flexure joint form and size and the swing performance

Abstract

The application discloses a flexible joint shape, position, size and swing performance optimization method, prepares an elastic green rubber sheet, preforms the elastic green rubber sheet, weighs and measures the thickness of each preformed elastic rubber sheet to meet the requirements, simulates vulcanization and makes the simulation vulcanization parameters consistent with the formal vulcanization parameters, after the simulation vulcanization is completed, T i and F i is made to meet the requirements, and then formal vulcanization is performed. The elastic green rubber sheet is pre-cured to ensure the thickness and thickness uniformity of the elastic rubber sheet, and then the shape, position, size, swing torque, composite angle, part interlayer bonding quality and other performances of the flexible joint are improved.

Description

Technical Field

[0001] This invention relates to the field of flexible joint forming technology, and specifically to a method for optimizing the shape, size, and oscillation performance of a flexible joint. Background Technology

[0002] The mechanical properties of the flexible joint in a oscillating nozzle have a significant impact on the attitude and trajectory control accuracy of the engine. During engine operation, the flexible joint bears the axial thrust generated during thrust formation and moves circumferentially along the oscillating center under the action of the servo control system. Simultaneously, the shape and position dimensions of the flexible joint also affect the assembly accuracy of the nozzle. Therefore, the shape and position dimensions and oscillation performance of the flexible joint are important factors influencing the working state of the flexible oscillating nozzle.

[0003] The flexible joint consists of a movable inverted conical shell made of metal, a reinforcing member, a fixed rear joint, and a rubber elastic layer. In the molding tooling, the rubber elastic layer is placed alternately and stacked between the inverted conical shell, the reinforcing member, and the fixed rear joint. Before placement, adhesive is applied to the metal part, and finally, after molding and vulcanization, it becomes a component. In the components of the flexible joint, the movable inverted conical shell, reinforcing parts, and fixed joint are all machined, resulting in stable dimensional and positional dimensions after forming. However, the rubber elastic layer is in a "fluffy and resilient" raw sheet state after rubber mixing, rolling, and cutting, making it difficult to control its dimensional and positional dimensions. Often, when placed between metal parts, the initial dimensional and positional dimensions of the entire flexible joint have already deviated significantly, requiring correction through subsequent molding tooling cavities. However, the thickness t and thickness uniformity of the rubber elastic layer between each layer of metal parts will deviate from the design value to some extent. When the deviation is large, it will directly cause significant deviations in the height and parallelism of the flexible joint. At the same time, the uneven thickness will cause poor symmetry of the flexible joint's swing torque and large compound deflection angle, which in severe cases will directly lead to the scrapping of the entire flexible joint. For mass production, this will cause significant economic losses and delays in the nozzle delivery production cycle. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned technical deficiencies by providing a method for optimizing the shape and position dimensions and swing performance of a flexible joint, thereby improving the shape and position dimensions and swing torque of the flexible joint.

[0005] To achieve the above objectives, the present invention provides a method for optimizing the shape, position, dimensions, and oscillation performance of a flexible joint. The flexible joint includes a movable inverted conical metal component, a reinforcing component, and a fixed joint. The optimization method is as follows: 1) Prepare elastic raw rubber sheets, and weigh and mark each elastic raw rubber sheet as A. i Let i represent the i-th elastic raw rubber sheet, where i is a natural number; and A i = A 0i + (7~8%)A 0i A0i This represents the theoretical weight of the i-th elastic raw rubber sheet; 2) Place the elastic raw rubber sheets one by one into the preforming molding tooling to obtain preformed elastic rubber sheets; 3) Weigh each pre-formed elastic film and record the weight as C. i The thickness is measured and recorded as t. i When C i and t i After the requirements are met, proceed to step 4. 4) Place the movable inverted cone metal part, the reinforcing part and the fixed rear joint into the integrated molding mold, and place pre-formed elastic films between the movable inverted cone metal part and the reinforcing part, between the reinforcing parts and the reinforcing part, and between the reinforcing part and the fixed rear joint. After the mold is closed, simulate vulcanization. The parameters of simulated vulcanization are consistent with the parameters of formal vulcanization. After the simulated vulcanization is completed, the parallelism and dimensional dimensions of the height h of the flexible joint are checked, and the thickness T of each pre-formed elastic film after simulated vulcanization is measured. i The uniformity of the preformed elastic film and the simulated total overflow amount E during vulcanization of the preformed elastic film were assessed. The weight F of each layer of the vulcanized elastic film was obtained by weighing the vulcanized elastic film. i When T i and F i After the requirements are met, proceed to step 5). 5) Sandblast, clean, and dry the movable inverted cone metal part, reinforcement, and fixed rear joint. Then apply curing adhesive to the mating surfaces and let them dry. After drying, place them in an integrated molding mold in an alternating manner. Place pre-formed elastic films between the movable inverted cone metal part and the reinforcement, between the reinforcements, and between the reinforcement and the fixed rear joint for formal vulcanization. When the amount of adhesive overflow during formal vulcanization is approximately equal to G, it is determined that the simulated vulcanization and the formal vulcanization are consistent, and the required flexible joint is obtained.

[0006] Further, the specific process of step 2) is as follows: the elastic raw rubber sheets are placed one by one into the pre-forming molding tooling, and after cold pressing at 1~2MPa and venting 2~3 times, the temperature is raised to 75±5℃, the pressure is increased to 3~3.5MPa, and the temperature and pressure are maintained for 3~5min, during which the pressure is quickly released and vented 2~3 times; the temperature is further raised to 90±5℃, the pressure is increased to 4~5MPa, and the temperature and pressure are maintained for 5~8min. Then, the pressure is maintained and cooled to room temperature in the furnace before the pressure is released and the pre-formed elastic rubber sheets are taken out.

[0007] Furthermore, in step 3), the following requirements must be met: t0 is the theoretical thickness of the elastic layer; D represents the total amount of adhesive overflow in the pre-formed film; When the conditions are not met At that time, the weight of each elastic raw rubber sheet is adjusted as follows: When t i When -t0≤0.2, adjust A i =1.12A 0i ; When t i When -t0≥0.35, adjust A i =1.04A 0i ; After repeating steps 1 and 2), weigh and measure the thickness of each pre-formed elastic film until the conditions are met. and ; When the requirements are met, record A as the result. i value.

[0008] Furthermore, in step 4), the requirement to be met is: ΣF i +E≈ΣC i And 0.05mm≤T i -t0≤0.15mm; If the requirements are not met, the weight of each elastic raw rubber sheet shall be adjusted as follows: When T i When -t0≤0.05, adjust A. i =1.10A 0i ; When T i When -t0≥0.15, adjust A i =1.06A 0i ; Repeat steps 1, 2, 3, and 4) to weigh and measure the thickness of each elastic film again until the conditions are met.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: First, the elastic raw rubber sheet is pre-cured to ensure the thickness and uniformity of the elastic rubber sheet, thereby improving the shape and position dimensions, swing torque, composite deflection angle, and interlayer bonding quality of the flexible joint. Detailed Implementation

[0010] The present invention will be further described in detail below with reference to specific embodiments to facilitate a clearer understanding of the present invention, but these embodiments do not constitute a limitation on the present invention.

[0011] Methods for optimizing the form, position, dimensions, and oscillation performance of flexible joints. The flexible joint includes a movable inverted conical metal component, a reinforcing component, and a fixed connector. The specific optimization methods are as follows: 1) Prepare elastic raw rubber sheets, and weigh and mark each elastic raw rubber sheet as A. iLet i represent the i-th elastic raw rubber sheet, where i is a natural number; and A i = A 0i + (7~8%)A 0i A 0i This represents the theoretical weight of the i-th elastic raw rubber sheet; 2) Place the elastic raw rubber sheets one by one into the preforming molding fixture. After cold pressing at 1~2MPa and venting 2~3 times, heat up to 75±5℃, pressurize to 3~3.5MPa, and hold for 3~5 minutes, during which the pressure is released quickly 2~3 times. Continue to heat up to 90±5℃, pressurize to 4~5MPa, and hold for 5~8 minutes. Then, after holding the pressure and cooling to room temperature in the furnace, release the pressure and take out the preformed elastic rubber sheets. 3) Weigh each pre-formed elastic film and record the weight as C. i The thickness is measured and recorded as t. i And it must meet the following requirements: t0 is the theoretical thickness of the elastic layer, to ensure that the preformed elastic film is still in a compressed state when it is placed in the flexible joint molding tooling, thereby ensuring that there are no gaps between the layers of the flexible joint metal parts. D represents the total amount of adhesive overflow in the pre-formed film; When the conditions are not met At that time, the weight of each elastic raw rubber sheet is adjusted as follows: When t i When -t0≤0.2, adjust A i =1.12A 0i ; When t i When -t0≥0.35, adjust A i =1.04A 0i ; After repeating steps 1 and 2), weigh and measure the thickness of each pre-formed elastic film until the conditions are met. and ; When the requirements are met, record A as the result. i value; 4) Place the movable inverted cone metal part, the reinforcing part and the fixed rear joint into the integrated molding mold, and place pre-formed elastic films between the movable inverted cone metal part and the reinforcing part, between the reinforcing parts and the reinforcing part, and between the reinforcing part and the fixed rear joint. After the mold is closed, simulate vulcanization. The parameters of simulated vulcanization are consistent with the parameters of formal vulcanization. After the simulated vulcanization is completed, the parallelism and dimensional dimensions of the height h of the flexible joint are checked, and the thickness T of each pre-formed elastic film after simulated vulcanization is measured. iThe uniformity of the preformed elastic film and the simulated total overflow amount E during vulcanization of the preformed elastic film were assessed. The weight F of each layer of the vulcanized elastic film was obtained by weighing the vulcanized elastic film. i ; If ΣF is satisfied i +E≈ΣC i And it must satisfy 0.05mm≤T i -When t0≤0.15mm (the shrinkage after molding of the flexible joint is about 0.7mm, and the average thickness of each layer is about 0.08mm), proceed to step 5). If the requirements are not met, the weight of each elastic raw rubber sheet shall be adjusted as follows: When T i When -t0≤0.05, adjust A. i =1.10A 0i ; When T i When -t0≥0.15, adjust A i =1.06A 0i ; Repeat steps 1, 2, 3, and 4) to weigh and measure the thickness of each elastic film again until the conditions are met. 5) Sandblast, clean, and dry the movable inverted cone metal part, reinforcement, and fixed rear joint. Then apply curing adhesive to the mating surfaces and let them dry. After drying, place them in an integrated molding mold in an alternating manner. Place pre-formed elastic films between the movable inverted cone metal part and the reinforcement, between the reinforcements, and between the reinforcement and the fixed rear joint for formal vulcanization. When the amount of adhesive overflow during formal vulcanization is approximately equal to G, it is determined that the simulated vulcanization and the formal vulcanization are consistent, and the required flexible joint is obtained.

[0012] A water pressure swing test was conducted. Examples 1 and 2 are conventional schemes, while Example 3 is the optimized method of the present invention, as detailed in Tables 1, 2, and 3. Table 1 Comparison of the geometric dimensions of flexible joints Table 2. Composite deflection angle of flexible joint under different pressures. Table 3. Swinging torque of flexible joint under various working conditions According to Table 1, the geometric dimensions of the flexible joint in Example 3 are better than those of the flexible joints in Examples 1 and 2, exhibiting better height stability and lower parallelism and coaxiality. This indicates that the geometric dimensions of the flexible joint in Example 3 better meet the design requirements.

[0013] According to Table 2, the flexible joint of Example 3 has a smaller composite deflection angle and a smaller residual composite deflection angle under various working conditions, and the flexible joint of Example 3 has higher stability under pressure.

[0014] According to Table 3, the flexible joint of Example 3 has better symmetry of swing torque under various working conditions than the flexible joints of Examples 1 and 2. Therefore, the flexible joint of Example 3 has higher stability during swing.

Claims

1. A method for optimizing the shape, position, dimensions, and oscillation performance of a flexible joint, the flexible joint comprising a movable inverted conical metal component, a reinforcing component, and a fixed joint, characterized in that: The optimization method is as follows: 1) Prepare elastic raw rubber sheets, and weigh and mark each elastic raw rubber sheet as A. i Let i represent the i-th elastic raw rubber sheet, where i is a natural number; and A i = A 0i + (7~8%)A 0i A 0i This represents the theoretical weight of the i-th elastic raw rubber sheet; 2) Place the elastic raw rubber sheets one by one into the preforming molding tooling to obtain preformed elastic rubber sheets; 3) Weigh each pre-formed elastic film and record the weight as C. i The thickness is measured and recorded as t. i When C i and t i After the requirements are met, proceed to step 4. 4) Place the movable inverted cone metal part, the reinforcing part and the fixed rear joint into the integrated molding mold, and place pre-formed elastic films between the movable inverted cone metal part and the reinforcing part, between the reinforcing parts and the reinforcing part, and between the reinforcing part and the fixed rear joint. After the mold is closed, simulate vulcanization. The parameters of simulated vulcanization are consistent with the parameters of formal vulcanization. After the simulated vulcanization is completed, the parallelism and dimensional dimensions of the height h of the flexible joint are checked, and the thickness T of each pre-formed elastic film after simulated vulcanization is measured. i The uniformity of the preformed elastic film and the simulated total overflow amount E during vulcanization of the preformed elastic film were assessed. The weight F of each layer of the vulcanized elastic film was obtained by weighing the vulcanized elastic film. i When T i and F i After the requirements are met, proceed to step 5). 5) Sandblast, clean, and dry the movable inverted cone metal part, reinforcement, and fixed rear joint. Then apply curing adhesive to the mating surfaces and let them dry. After drying, place them in an integrated molding mold in an alternating manner. Place pre-formed elastic sheets between the movable inverted cone metal part and the reinforcement, between the reinforcements, and between the reinforcement and the fixed rear joint for formal vulcanization. When the amount of adhesive overflow during formal vulcanization is approximately equal to G, it is determined that the simulated vulcanization and the formal vulcanization are consistent, and the required flexible joint is obtained. In step 3), the following requirements must be met: t0 is the theoretical thickness of the elastic layer; D represents the total amount of adhesive overflow in the pre-formed film; When the conditions are not met At that time, the weight of each elastic raw rubber sheet is adjusted as follows: When t i When -t0≤0.2, adjust A i =1.12A 0i ; When t i When -t0≥0.35, adjust A i =1.04A 0i ; After repeating steps 1 and 2), weigh and measure the thickness of each pre-formed elastic film until the conditions are met. and ; When the requirements are met, record A as the result. i value; In step 4), the requirement to be met is: ΣF i +E≈ΣC i And 0.05mm≤T i -t0≤0.15mm; If the requirements are not met, the weight of each elastic raw rubber sheet shall be adjusted as follows: When T i When -t0≤0.05, adjust A. i =1.10A 0i ; When T i When -t0≥0.15, adjust A i =1.06A 0i ; Repeat steps 1, 2, 3, and 4) to weigh and measure the thickness of each elastic film again until the conditions are met.

2. The method for optimizing the shape, position, dimensions, and oscillation performance of the flexible joint according to claim 1, characterized in that: The specific process of step 2) is as follows: place the elastic raw rubber sheets one by one into the pre-forming molding tooling, and after cold pressing at 1~2MPa and venting 2~3 times, heat up to 75±5℃, pressurize to 3~3.5MPa, and hold the temperature and pressure for 3~5min, during which the pressure is released quickly 2~3 times; continue to heat up to 90±5℃, pressurize to 4~5MPa, hold the temperature and pressure for 5~8min, and then hold the pressure and cool to room temperature with the furnace before releasing the pressure and taking out the pre-formed elastic rubber sheets.

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