Vibration reduction and sound insulation acoustic material valve and design method thereof

Abstract

The invention provides a vibration reduction and sound insulation acoustic material valve and a design method thereof, and belongs to the field of valve design. The valve body is of a valve body structure formed by bonding three basic materials including a metal material, a CFRP material and a damping material instead of an all-metal structure of an original metal valve body, the metal material serves as an inner container, the outer layer of the inner container is coated with the CFRP material to form a CFRP layer, the outer layer of the CFRP is coated with the damping material to form a damping material layer, and the three materials are bonded into a whole through epoxy resin. And materials coated at different positions of the valve body and the thicknesses of the materials are different. The invention further provides a design method of the vibration reduction and sound insulation acoustic material valve. By utilizing the characteristics of high specific strength and high specific modulus of the CFRP material and the vibration reduction and sound insulation performance of the CFRP material and the damping material, the noise reduction and vibration reduction functions of the material can be realized on the premise that the structural weight is not increased and the mechanical property of the material is ensured.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of valve design, and relates to a damping and sound insulation acoustic material valve and a design method thereof, in particular to a metal / CFRP / damping composite material valve and a design method thereof, wherein the valve body of the composite material valve is a structure with a metal material as an inner container, and a CFRP material and a damping material coated on the outer layer. BACKGROUND

[0002] Currently, the valve structures used in ships, transportation and industrial equipment are mostly made of metal materials such as steel, aluminum and titanium alloy. These materials have high strength and rigidity, but have large density and heavy weight. Especially in large-diameter or long-distance conveying systems, the weight of the valve significantly increases, becoming an important part of the system mass. In addition, due to the poor damping performance of traditional metal materials, the valve structure is prone to structural vibration and noise under the action of mechanical vibration or fluid excitation, affecting the reliability and service life of the system. Especially in the application scenarios such as ships and deep-sea equipment with strict noise control requirements, the influence is more significant.

[0003] In order to reduce the vibration and noise of the valve structure, currently, methods such as pasting or coating damping materials on the surface of the metal valve body and adding sound insulation covers are used for improvement. However, these traditional methods have obvious shortcomings: on the one hand, the additional damping structure significantly increases the overall weight, which is not conducive to the lightweight of the system; on the other hand, if the amount of metal material is reduced to control the weight and replaced by damping materials with poor mechanical properties, it is easy to cause insufficient stiffness and strength of the valve structure, shorten the service life, and affect the stable operation of the valve under complex working conditions.

[0004] Carbon fiber reinforced composite material (CFRP, Carbon Fiber Reinforced Plastic) has been widely used in aerospace, rail transportation and other fields due to its light weight, high specific strength, large specific stiffness, excellent damping performance and strong designability. The resin matrix itself has good internal damping characteristics, which can effectively absorb and dissipate structural vibration energy and suppress resonance. Therefore, introducing CFRP material into the valve structure design to replace part of the traditional metal material can not only reduce the weight of the structure, but also improve the damping and sound insulation ability, which is an effective way to realize high-performance valves.

[0005] To this end, a valve design scheme of metal / CFRP / damping material integrated composite structure is proposed: the core pressure-bearing parts of the valve (such as the inner container, sealing interface, etc.) are constructed by metal materials, the main load-bearing shell is constructed by wrapping the metal inner container with CFRP composite material, and a functional damping coating or composite layer is arranged on the outer layer of CFRP. The structure realizes the synergistic optimization of strength, stiffness and damping performance without increasing the overall weight, improves the anti-vibration and sound insulation performance of the valve, and effectively meets the application requirements of high-performance, low-noise and lightweight valves for ships and deep-sea equipment. SUMMARY

[0006] In view of the disadvantages of large weight and poor vibration reduction effect of traditional single metal material, the application provides a new type of vibration reduction laminated material valve, the main structure of the valve body is divided into three layers of metal, CFRP and damping material, the high specific strength and high specific modulus characteristics of the CFRP material, and the vibration reduction and sound insulation performance of the CFRP material and the damping material can realize the noise reduction and vibration reduction function of the material without increasing the structure weight and ensuring the mechanical properties of the material.

[0007] In order to achieve the above-mentioned purpose, the technical scheme adopted by the application is:

[0008] A vibration reduction and sound insulation acoustic material valve is a carbon fiber composite material valve, the valve body of the carbon fiber composite material valve is a structure with a metal material as an inner container and an outer layer of CFRP material and damping material. Specifically, the vibration reduction and sound insulation acoustic material valve comprises a valve body 2, a spring gland 3, a valve seat 4, a ball 5, a spring 6, a diffuser 7, a perforated plate 8, a flow guide sleeve 9, a large bolt 10, a guide sleeve 11, a valve stem 12, an upper cover 13 and a sealing element. Compared with the traditional metal valve, the design improvement point (improvement of the original metal valve body) of the application is that the original metal valve body 1 is modified, the inclined curved surface ring outer wall 101 of the original metal valve body 1 is changed to an equal-diameter curved surface ring outer wall 204 and is thinned, the middle flange 102 of the original titanium alloy valve body 1 is removed and is changed to a composite material valve body middle flange 205 structure, the inner side of the original metal valve body end flange 102 and the outer wall of the large bolt position 103 are thinned to form a composite material valve body end flange 206 and a large bolt position 207, and then the metal inner container 201 of the valve body 2 is formed; the thinned removed metal is replaced with CFRP material at the equal-diameter ring outer wall 204 by using the equal-stiffness replacement principle, the removed metal is replaced with CFRP material at the inner side of the end flange 206 and the outer wall of the large bolt position 207 by using the equal-thickness replacement, and only 1-2 layers of CFRP material layer are coated as the appearance in the remaining outer surface area, the CFRP material layer 202 is formed on the outside of the valve body, and the metal inner container 201 and the CFRP material layer 202 form Figure 5The structure of the CFRP / metal composite valve shown; the weight difference between the CFRP / metal composite valve structure and the original metal valve 1 is used to form a metal / CFRP / damping material composite valve body 2 structure with the same weight as the original metal valve by coating the outer layer of the CFRP material layer 202 at the position of the equal-diameter ring-shaped outer wall 204 with a certain mass of damping material layer 203, and the three materials are bonded together by epoxy resin to form a whole, wherein the materials and material layer thicknesses coated at different positions of the valve body are different (the positions coated with thicker CFRP layers and damping layers are the ring-shaped outer walls along the flow direction of the valve body, the positions coated with only CFRP layers and thicker CFRP layers are the inner walls of the two flanges and the outer walls of the positions connecting the large bolts, and the remaining outer surface areas are only coated with thin CFRP layers as the appearance). Specifically:

[0009] A first thread 208 is machined at the inlet of the valve body 2 for connecting a spring gland 3, the spring gland 3 is in clearance fit with the outer wall surface of the valve seat 4, and the valve seat 4 is in contact with the ball 5 through a dynamic sealing ring; the valve seat 4 is fixed and constrained by the contact of the ball 5 and the valve seat 4 and the compression force generated by the spring 6 located between the spring gland 3 and the valve seat 4.

[0010] A second thread 209 is machined at the outlet of the valve body 2 for connecting a diffuser 7, the diffuser 7 is in contact with an orifice plate 8, and the orifice plate 8 is in contact with a flow guide sleeve 9; the orifice plate 8 and the flow guide sleeve 9 are fixed and constrained by the contact of the inner wall structure of the metal inner liner 201 of the valve body 2 and the diffuser 7.

[0011] A first through hole 210 is machined on the middle flange 205 of the valve body 2 for inserting a valve stem 12 and an upper cover 13, the end of the valve stem 12 is embedded in the ball 5 to control the rotation of the ball 5 and limit the degrees of freedom.

[0012] N threaded holes 211 are machined around the first through hole 210 of the valve body 2 for connecting the valve body 2 and the upper cover 13 with bolts 14, and the upper cover 13 is used to connect the valve execution structure. The N is preferably 6.

[0013] A third thread 212 is machined on the lower end of the valve body 2 for connecting a large bolt 10, and the end of the large bolt 10 is connected to the ball 5 through a guide sleeve 11 to limit the degrees of freedom of the ball 5.

[0014] M second through holes 213 are machined on the end flanges 206 on both sides of the valve body 2 for connecting the valve body 2 and the pipeline accessories with bolts. The M is preferably 6.

[0015] A design method of a damping and sound insulation acoustic material valve, comprising the following steps:

[0016] Firstly, the structure of the original metal valve body 1 is improved.

[0017] The inclined curved surface ring outer wall 101 of the original metal valve body 1 is changed to the equal-diameter curved surface ring outer wall 204 of the valve body 2.

[0018] The middle flange 102 flange of the original metal valve body 1 is removed and changed to a square middle flange 205 structure for the winding and molding of the CFRP prepreg.

[0019] The end flange 103 and the large bolt position 104 on both sides of the original titanium alloy valve body 1 are not modified in shape, but the outer wall is thinned to form the composite material valve body end flange 206 and the large bolt position 207, and then the metal liner 201 of the valve body 2 is formed.

[0020] Second step, CFRP material is used to replace the metal material removed at the position of the ring outer wall 204 of the original metal valve body in the previous step; and the thickness of the replaced CFRP material layer 202 is determined by the equal stiffness replacement formula. The formula is:

[0021]

[0022] In the formula: , The thickness of the metal material to be replaced and the thickness of the replaced CFRP material layer 202, respectively; , The stiffness of the metal and the stiffness of the CFRP material, respectively; The thickness index coefficient, usually taking a value of 1-3.

[0023] According to the values of , , and , the value of is determined. The metal liner 201 after removing part of the metal material and the CFRP material layer 202 are surface glued.

[0024] Third step, the inner side of the end flange 103 and the outer wall connecting the large bolt position 104 of the original metal valve body 1 are replaced by equal thickness, that is, the original part of the metal material is removed, and the thickness is and , and the equal-thickness CFRP material layer 202 is replaced on the surface, and the thickness is and , wherein , . The remaining outer surface area, i.e. the edge and outer side of the end flange 103, the surface of the middle flange 102 and the lower edge of the large bolt position 104, is only coated with 1-2 layers of CFRP material layer 202 as an appearance. Finally, the metal / CFRP composite valve body is formed as shown in Figure 5 .

[0025] Fourth step, calculate the weight of the metal / CFRP composite valve body in the fourth step compared with the original metal valve body 1. That is:

[0026]

[0027] In the formula: The weight of the metal / CFRP composite valve body compared with the original metal valve body 1; And The weight of the original metal valve body 1 and the weight of the metal / CFRP composite valve body, respectively.

[0028] Fifth step, a certain thickness of damping material with a mass of is glued to the CFRP surface at the position of the ring-shaped outer wall of the metal / CFRP composite valve body, and finally a metal / CFRP / damping composite valve body 2 is formed. All contact surfaces of different materials are glued together by epoxy resin to form a complete valve body.

[0029] The beneficial effects of the present application are:

[0030] The present application adopts a metal / CFRP / damping material composite structure design, which realizes the significant improvement of lightweight and vibration and noise reduction performance under the premise of ensuring the mechanical properties of the valve. Its technical effects mainly reflect in three aspects:

[0031] (1) By replacing part of the metal material with CFRP material and using the design method of equal stiffness replacement and equal thickness replacement, the weight of the valve is effectively reduced while maintaining the structural stiffness, realizing the lightweight design of the traditional metal valve;

[0032] (2) By using the inherent high damping characteristics of CFRP material and the additional damping material layer on the outer layer, the vibration energy dissipation capacity and noise suppression effect of the valve are significantly improved, and the harmonic response analysis results show that the vibration amplitude of the composite structure valve is significantly reduced;

[0033] (3) By accurately calculating the weight reduction after CFRP replacement, and coating the damping material with the same mass at the position of the ring-shaped outer wall, the overall weight is consistent with the original metal valve, forming a functional gradient structure of "metal pressure bearing-CFRP force bearing-damping vibration reduction". This design makes the valve show more excellent comprehensive performance than the traditional metal valve in application scenarios such as ships, deep sea equipment, and other strict requirements for weight, vibration and noise control. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is a schematic diagram of the original metal valve body structure.

[0035] Figure 2is a valve body structure diagram of a valve body after modification of the outer contour shape of an original metal valve body.

[0036] Figure 3 is a valve body structure diagram of a metal / CFRP / damping material composite valve.

[0037] Figure 4 is Figure 2 is a half sectional view of a valve body structure of a valve body after modification of the outer contour shape of an original metal valve body.

[0038] Figure 5 is a half sectional view of a valve body structure of a metal / CFRP material composite valve.

[0039] Figure 6 is Figure 3 is a half sectional view of a valve body structure diagram of a metal / CFRP / damping material composite valve.

[0040] Figure 7 is a half sectional view of a metal / CFRP / damping material composite valve assembly diagram.

[0041] Figure 8 is a metal / CFRP / damping material composite valve design method flowchart.

[0042] Figure 9 is a harmonic response analysis result diagram.

[0043] In the figure: 1 original metal valve body; 2 valve body; 3 spring cover; 4 valve seat; 5 ball; 6 spring; 7 diffuser; 8 orifice plate; 9 flow guide sleeve; 10 large bolt; 11 guide sleeve; 12 valve stem; 13 upper cover; 14 bolt;

[0044] 101 inclined curved surface ring outer wall; 102 original metal valve body middle flange; 103 original metal valve body end flange; 104 original metal valve body large bolt position; 201 metal liner; 202 CFRP material layer; 203 damping material layer; 204 constant diameter curved surface ring outer wall; 205 composite material valve body middle flange; 206 composite material valve body end flange; 207 composite material valve body large bolt position; 208 first thread; 209 second thread; 210 first through hole; 211 threaded hole; 212 third thread; 213 second through hole. DETAILED DESCRIPTION

[0045] The present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0046] The application discloses a kind of damping sound insulation acoustic material valve, it is a carbon fiber composite material valve, the valve body of the carbon fiber composite material valve is the structure with metal material as inner container, outer layer is coated with CFRP material and damping material.Specifically, the damping sound insulation acoustic material valve includes valve body 2, spring gland 3, valve seat 4, ball 5, spring 6, diffuser 7, orifice plate 8, flow guide sleeve 9, large bolt 10, guide sleeve 11, valve stem 12, upper cover 13 and sealing element.Compared with traditional metal valve, the design improvement point (improve the original metal valve body) of the application is to modify the external structure of the original metal valve body 1, change the inclined curved surface ring outer wall 101 of the original metal valve body 1 to the equal-diameter curved surface ring outer wall 204 and thin it, remove the flange of the original titanium alloy valve body 1, change the structure of the composite material valve middle flange 205, and thin the inner side of the original metal valve body end flange 102 and the outer wall of the large bolt position 103 to form the composite material valve end flange 206 and the large bolt position 207, and then form the metal inner container 201 of the valve body 2; the removed metal is replaced with CFRP material at the equal-diameter ring outer wall 204 by using the equal-stiffness replacement principle, the removed metal is replaced with CFRP material at the inner side of the end flange 206 and the outer wall of the large bolt position 207 by using the equal-thickness replacement, and only 1-2 layers of CFRP material layer are coated as the appearance in the remaining outer surface area to form the CFRP material layer 202 on the valve body, and the metal inner container 201 and the CFRP material layer 202 form the CFRP / metal composite material valve structure shown in the figure; Figure 5 The weight difference between the CFRP / metal composite material valve structure and the original metal valve 1 is used to coat a certain mass damping material layer 203 on the outer layer of the CFRP material layer 202 at the equal-diameter ring outer wall 204 position to form the composite material valve body 2 structure of metal / CFRP / damping material with the same weight as the original metal valve, and the three materials are integrally formed by epoxy resin bonding, wherein the materials and material layer thicknesses coated at different positions of the valve body are different.

[0047] A first thread 208 is processed at the inlet of the valve body 2 for connecting the spring gland 3, the spring gland 3 is gap-fitted with the outer wall surface of the valve seat 4, and the valve seat 4 is in contact with the ball 5 through a dynamic sealing ring; the valve seat 4 is fixedly constrained by the contact of the ball 5 and the valve seat 4 and the compression force generated by the spring 6 located between the spring gland 3 and the valve seat 4.

[0048] A second thread 209 is processed at the outlet of the valve body 2 for connecting the diffuser 7, the diffuser 7 is in contact with the orifice plate 8, the orifice plate 8 is in contact with the flow guide sleeve 9, and the orifice plate 8 and the flow guide sleeve 9 are fixedly constrained through the contact of the metal inner container 201 of the valve body 2 and the diffuser 7.

[0049] The middle flange 205 of the valve body 2 is processed with a first through hole 210 for inserting the valve stem 12 and the upper cover 13, and the end of the valve stem 12 is embedded with the ball 5 to control the rotation of the ball 5 and limit the degree of freedom.

[0050] The first through hole 210 of the valve body 2 is processed with N threaded holes 211 around it for connecting the valve body 2 with the bolt 14 of the upper cover 13, and the upper cover 13 is used to connect the valve execution structure. The N is preferably 6.

[0051] The lower end of the valve body 2 is processed with a third thread 212 for connecting the large bolt 10, and the end of the large bolt 10 is connected with the ball 5 through the guide sleeve 11 to limit the degree of freedom of the ball 5.

[0052] The end flanges 206 on both sides of the valve body 2 are each processed with M second through holes 213 for bolt connection of the valve body 2 with the pipeline accessories. The M is preferably 6.

[0053] A design method of a damping and sound insulation acoustic material valve, comprising the following steps:

[0054] Firstly, the original metal valve body 1 is structurally improved.

[0055] The inclined curved surface ring outer wall 101 of the original metal valve body 1 is changed to the equal-diameter curved surface ring outer wall 204 of the valve body 2;

[0056] The flange of the middle flange 102 of the original metal valve body 1 is removed and changed to the square middle flange 205 structure for the winding and molding of the CFRP prepreg.

[0057] The shapes of the end flanges 103 on both sides of the original metal valve body 1 and the large bolt position 104 are not modified, but the outer walls of the two are thinned to form the composite material valve body end flange 206 and the large bolt position 207, and then form the metal inner liner 201 of the valve body 2.

[0058] Secondly, the CFRP material is used to replace the metal material removed at the position of the ring outer wall 204 of the original metal valve body in the previous step, and the thickness of the replaced CFRP material layer 202 is determined through the equal stiffness replacement formula. The formula is:

[0059]

[0060] In the formula: , The metal material thickness of the replaced part and the thickness of the replaced CFRP material layer 202 are respectively; , The metal stiffness and the CFRP material stiffness are respectively; The thickness index coefficient is usually 1-3. The metal material is titanium alloy material. The value is taken as , , and take .

[0061] According to formula (1), and take can be approximated to , that is, the metal material with a thickness of 3 mm is replaced by the CFRP material with a thickness of 6.4 mm, and the CFRP material is bonded to the surface of the equal-thickness annular outer wall 204 of the metal liner.

[0062] Third step, the inner side of the flange 103 on both sides of the original metal valve body 1 and the outer wall of the position 104 connected to the large bolt are replaced with equal thickness, that is, the original part of the metal material is removed, and the thickness is and , and the CFRP material layer 202 with equal thickness is replaced on the surface, and the thickness is and . The remaining outer surface area, that is, the edge and outer side of the end flange 103, the surface of the middle flange 102 and the lower edge of the large bolt position 104, is only coated with 1-2 layers of CFRP material layer 202 as appearance. Finally, the metal / CFRP composite valve body shown in Figure 5 is formed.

[0063] Fourth step, calculate the weight reduction of the metal / CFRP composite valve body in the fourth step compared with the original metal valve body 1. That is:

[0064]

[0065] In the formula: is the weight reduction of the metal / CFRP composite valve body compared with the original metal valve body 1; and are the weight of the original metal valve body 1 and the weight of the metal / CFRP composite valve body, respectively. Among them, , , get .

[0066] Fifth step, a certain thickness of rubber damping material with a mass of is glued to the CFRP surface at the position of the annular outer wall of the metal / CFRP composite valve body, and finally a metal / CFRP / rubber composite valve body 2 is formed. All contact surfaces of different materials are glued together by epoxy resin to form a complete valve body.

[0067] The harmonic response analysis is carried out on the original metal valve, the metal / CFRP composite valve and the metal / CFRP / rubber composite valve, and the results are shown in Figure 9 . It can be found that the metal / CFRP / rubber damping composite valve has better anti-vibration effect.

[0068] The above described embodiments only express the implementation of the present application, but cannot be understood as the limitation of the scope of the patent of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application.

Claims

1. A valve of a vibration and sound insulation acoustic material, comprising a valve body (2), a spring gland (3), a valve seat (4), a ball (5), a spring (6), a diffuser (7), an orifice plate (8), a flow guide sleeve (9), a large bolt (10), a guide sleeve (11), a valve stem (12), an upper cover (13) and a seal; characterized in that, The damping and sound insulation acoustic material valve is a structure with a metal material as an inner container, an outer layer of CFRP material and damping material. The oblique curved surface ring outer wall (101) of the original metal valve body (1) is designed as an equal-diameter curved surface ring outer wall (204) and is thinned; the middle flange (102) flange of the original metal valve body (1) is removed and designed as a composite material valve body middle flange (205) structure; the inner side of the original metal valve body end flange (102) and the outer wall of the large bolt position (103) are thinned to form a composite material valve body end flange (206) and a large bolt position (207), thereby forming a metal inner container (201) of the valve body (2); The thinned and removed metal is replaced with CFRP material at the equal-diameter curved surface ring outer wall (204) by using the equal stiffness replacement principle, and the removed metal is replaced with CFRP material at the inner side of the end flange (206) and the outer wall of the large bolt position (207) by using the equal thickness replacement, and only a CFRP material layer (202) is coated as an appearance on the remaining outer surface area to obtain a CFRP / metal composite material valve structure.

2. A valve of a sound damping acoustic material according to claim 1, characterized in that, Based on the weight difference between the CFRP / metal composite material valve structure and the original metal valve body (1), the outer layer of the CFRP material layer (202) at the equal-diameter curved surface ring outer wall (204) position is coated with a damping material layer (203) to form a metal / CFRP / damping material composite material valve body structure with the same weight as the original metal valve, and the three materials are connected to form an integral whole, wherein the materials and material layer thicknesses coated at different positions of the valve body are different.

3. A valve of a sound damping acoustic material according to claim 2, characterized in that, A first thread (208) is machined at the inlet of the valve body (2) for connecting a spring gland (3), the spring gland (3) is in gap cooperation with the outer wall surface of a valve seat (4), the valve seat (4) is in contact with a ball (5) through a dynamic sealing ring; the valve seat (4) is fixed and constrained by the contact of the ball (5) and the valve seat (4) and the compression force generated by a spring (6); the spring (6) is located between the spring gland (3) and the valve seat (4).

4. A valve of a sound damping acoustic material according to claim 3, characterized in that, A second thread (209) is machined at the outlet of the valve body (2) for connecting a diffuser (7), the diffuser (7) is in contact with an orifice plate (8), the orifice plate (8) is in contact with a flow guide sleeve (9), the orifice plate (8) and the flow guide sleeve (9) are fixed and constrained by the contact of the inner wall structure of the metal inner container (201) of the valve body (2) and the diffuser (7).

5. A valve of a sound damping acoustic material according to claim 4, characterized in that, A first through hole (210) is machined in the composite material valve body middle flange (205) for putting in a valve stem (12) and an upper cover (13), the valve stem (12) is embedded at the end of the ball (5) to control the rotation of the ball (5) and limit the degrees of freedom; A plurality of threaded holes (211) are machined around the first through hole (210) for bolt connection of the valve body (2) and the upper cover (13), and the upper cover (13) is used for connecting a valve actuating structure.

6. A valve of a sound damping acoustic material according to claim 5, characterized in that, The lower end of the valve body (2) is machined with a third thread 212 for connecting a large bolt (10), the end of which is connected to a ball (5) through a guide sleeve (11) to limit the freedom of the ball (5).

7. A valve of a sound damping acoustic material according to claim 6, characterized in that The end flanges (206) on both sides of the valve body (2) are each machined with a plurality of second through holes (213) for connecting the valve body (2) with pipelines.

8. A method of designing a valve of a sound damping and sound insulating acoustic material according to any one of claims 1-7, characterized in that, The method comprises the following steps: Firstly, the original metal valve body (1) is structurally improved; The inclined curved surface ring outer wall (101) of the original metal valve body (1) is changed to the equal-diameter curved surface ring outer wall (204) of the valve body (2); The flange of the middle flange (102) of the original metal valve body (1) is removed and changed to the square composite material valve body middle flange (205) structure for winding and forming the CFRP prepreg; The shapes of the end flanges (103) and the large bolt positions (104) on both sides of the original metal valve body (1) are not modified, the outer walls thereof are thinned to form the composite material valve body end flanges (206) and the large bolt positions (207), and then the metal inner liner (201) of the valve body (2) is formed; Secondly, the CFRP material is used to replace the metal material removed at the equal-diameter curved surface ring outer wall (204) position in the first step, and the thickness of the replaced CFRP material layer (202) is determined through the equal-stiffness replacement formula; the formula is: ； wherein: , are the thickness of the metal material of the replaced portion and the thickness of the replaced CFRP material layer (202), respectively; , are the metal stiffness and the CFRP material stiffness, respectively; is the thickness exponent coefficient; According to the values of , , and , the value of is determined; and the metal liner (201) after removing part of the metal material and the CFRP material layer (202) surface are connected; Third step, the inner side of the flange (103) on both sides of the original metal valve body (1) and the outer wall of the position of the large bolt (104) are replaced with equal thickness, that is, the original part of the metal material is removed, and the thickness is and , which is replaced with a CFRP material layer (202) with a thickness of and , wherein , ; the remaining outer surface area, that is, the edge and the outer side of the end flange (103), the surface of the middle flange (102), and the lower edge of the large bolt position (104), is only coated with a CFRP material layer (202) as an appearance, obtaining a metal / CFRP composite valve valve body; Step 4, calculate the weight of the metal / CFRP composite valve body reduced compared with the original metal valve body (1) ; that is: ； wherein: and are the weight of the original metal valve body (1) and the weight of the metal / CFRP composite valve body, respectively; Fifth step, the damping material with mass of is glued on the CFRP surface at the position of the outer wall of the metal / CFRP composite valve body, and finally a metal / CFRP / damping composite valve body (2) is formed.

9. A method of designing a valve for a sound damping acoustic material according to claim 8, wherein, All contact surfaces of different materials are glued to form a complete valve body through epoxy resin glue.

10. A method of designing a valve for a sound damping acoustic material according to claim 8, wherein, In the second step, the thickness index coefficient is 1-3; in the third step, the CFRP material layer (202) is coated with 1-2 layers.

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