Manufacturing process of rubber buffer seat

Abstract

The invention relates to the technical field of rubber products, in particular to a rubber buffer seat manufacturing process which comprises the following steps: coating a glue solution in a mold cavity; covering the bottom and the waist part of the mold cavity with an outer-layer sealing film, attaching the outer-layer sealing film to the interior of the mold cavity, and compacting; twelve bottom cord thread layers are attached to the positions, corresponding to the bottom of the mold cavity, of the outer sealing rubber sheet, and every two adjacent bottom cord thread layers are connected through a glue solution; a waist cord thread layer is attached to the position, corresponding to the waist of the mold cavity, of the outer-layer sealing rubber sheet, and every two adjacent waist cord thread layers are connected through a glue solution; covering the bottom cord thread layer and the waist cord thread layer with an inner-layer sealing film and compacting the inner-layer sealing film; and the male die is pressed downwards into the die cavity for compaction, and the inner-layer sealing rubber sheet, the outer-layer sealing rubber sheet, the bottom cord thread layer and the waist cord thread layer are vulcanized and compounded together. The rubber buffer seat is less in deformation in high-temperature and high-pressure environments, is not easy to damage, is higher in durability and service life, and can meet the requirement of frequent emission.

Description

Technical Field

[0001] The present application relates to the technical field of rubber products, and in particular to a manufacturing process of a rubber buffer seat. Background Art

[0002] When facing the strong impact and ultra-high temperature and high pressure launch conditions during aircraft takeoff, a buffer base is often needed as a buffer to reduce the impact of the impact during aircraft takeoff. Currently, most buffer bases use rubber bases, which play an important role in withstanding strong impact and high temperature and high pressure.

[0003] Traditional buffer bases have some limitations in design and manufacturing processes, and it is difficult to meet the stringent performance requirements of strong impact and ultra-high temperature launches during current aircraft takeoffs and frequent takeoffs. Their service life is not long and they are prone to deformation or damage in high temperature and high pressure environments. Their durability and service life are difficult to meet the needs of frequent launches. Summary of the invention

[0004] The present application aims to solve at least one of the above-mentioned technical problems in the prior art to a certain extent. To this end, the present application provides a rubber buffer seat manufacturing process, and the rubber buffer seat manufactured by this process has less deformation under high temperature and high pressure environment, is not easy to be damaged, has higher durability and service life, and can meet the needs of frequent launch.

[0005] A rubber buffer seat manufacturing process, characterized in that it includes the following steps: Apply glue liquid in the mold cavity; Lay the cut outer sealing film flat on the workbench and apply glue; After the glue on the outer sealing film is dry, the outer sealing film covering the bottom and waist of the mold cavity is attached to the inside of the mold cavity and compacted; Twelve bottom cord layers are bonded to the outer sealing film at the position corresponding to the bottom of the mold cavity by glue, wherein the first two bottom cord layers are arranged in a cross-staggered manner, and the third to tenth bottom cord layers are bonded in a staggered manner in a cross-shaped pattern, and two adjacent bottom cord layers are connected by glue; The waist cord layer is bonded to the position of the waist of the mold cavity on the outer sealing film by glue. The waist cord layer adopts a 45° positive and negative winding molding and bonding process, one positive and one negative bonding, a total of 12 layers of cords are bonded, and the adjacent two waist cord layers are connected by glue; Lay the cut inner sealing film flat on the workbench and apply glue; After the glue on the inner sealing film is dry, the inner sealing film is used to cover the bottom cord layer and the waist cord layer and compacted; The convex mold is pressed down into the mold cavity for compaction, and then the vulcanization process is started to vulcanize and compound the inner sealing film, the outer sealing film, the bottom cord layer and the waist cord layer together.

[0006] In an optional or preferred embodiment, when applying the glue, the glue is applied once to the bottom of the mold cavity and twice to the waist of the mold cavity.

[0007] In an optional or preferred embodiment, the glue applied to the bottom of the mold cavity and the waist of the mold cavity is XY507 glue.

[0008] In an optional or preferred embodiment, an aramid reinforcement layer is added at the flange portion after every two layers of cords are bonded together.

[0009] In an optional or preferred embodiment, the height of the waist cord layer at the flange portion is 3 mm higher than the mold edge.

[0010] In an alternative or preferred embodiment, the waist cord layer is interlaced with the bottom cord layer.

[0011] In an optional or preferred embodiment, the adhesive for bonding the outer sealing film to the inside of the mold cavity is a bulk adhesive made by dissolving nitrile-polyvinyl chloride, and the adhesive for bonding the inner sealing film to the waist cord layer and the bottom cord layer is a bulk adhesive made by dissolving nitrile-polyvinyl chloride blended adhesive.

[0012] In an optional or preferred embodiment, the adhesive connecting two adjacent bottom cord layers is a bulk adhesive made of nitrile rubber-natural rubber, and the adhesive connecting two adjacent waist cord layers is a bulk adhesive made of nitrile rubber-natural rubber.

[0013] In an optional or preferred embodiment, both the bottom cord layer and the waist cord layer are made of nylon cords.

[0014] In an optional or preferred embodiment, the inner sealing film is covered with an electromagnetic shielding layer.

[0015] Based on the above technical solution, the embodiments of the present application have at least the following beneficial effects: the rubber buffer seat produced by this process deforms less under high temperature and high pressure environment, is not easy to be damaged, has higher durability and service life, and can meet the needs of frequent launches. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present application is further described below in conjunction with the accompanying drawings and embodiments; Figure 1 is a schematic diagram of the structure of the rubber buffer seat provided in an embodiment of the present application; Figure 2 yes Figure 1A schematic diagram of the positional relationship between a portion of the rubber buffer seat and the mold cavity provided in the illustrated embodiment; Figure 3 It is a schematic diagram of the molding and bonding process of 45° forward and reverse winding in this application. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application.

[0018] The following is a further detailed description of the implementation of the present application in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but cannot be used to limit the scope of the present application.

[0019] In the description of the embodiments of the present application, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0020] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0021] In the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0022] When facing strong impact, ultra-high temperature and high pressure launch conditions, a buffer base is often needed as a buffer to reduce the impact of the launch shock. Currently, most buffer bases use rubber buffer seats, which play an important role in withstanding strong impact and high temperature and high pressure.

[0023] Traditional rubber buffer seats have some limitations in design and manufacturing process, and it is difficult to meet the stringent performance requirements of modern high-impact and ultra-high-temperature launches. Their service life is not long and they are prone to deformation or damage in high-temperature and high-pressure environments. Their durability and service life are difficult to meet the needs of frequent launches.

[0024] The present application provides a rubber buffer seat manufacturing process, comprising the following steps: Apply glue liquid in the mold cavity 100; Lay the cut outer sealing film 200 flat on the workbench and apply glue liquid; After the glue on the outer sealing film 200 is dried, the outer sealing film 200 covering the bottom 300 and the waist 400 of the mold cavity 100 is attached to the inside of the mold cavity 100 and compacted; Twelve bottom cord layers 500 are bonded to the outer sealing film 200 at the position corresponding to the bottom of the mold cavity 100 by glue, wherein the first two bottom cord layers 500 are arranged in a cross-staggered manner, and the third to tenth bottom cord layers 500 are staggered and bonded in a cross-shaped manner, and two adjacent bottom cord layers 500 are connected by glue; The waist cord layer 600 is bonded to the position of the waist 400 of the mold cavity 100 on the outer sealing film 200 by glue, wherein the waist cord layer 600 adopts a 45° positive and negative winding molding and bonding process, and is bonded one positive and one negative, with a total of 12 layers of cords bonded, and two adjacent layers of waist cord layers 600 are connected by glue; Lay the cut inner sealing film 700 flat on the workbench and apply glue; After the glue on the inner sealing rubber sheet 700 is dried, the inner sealing rubber sheet 700 is covered with the bottom cord layer 500 and the waist cord layer 600 and compacted; The convex mold is pressed down into the mold cavity 100 for compaction, and then the vulcanization process is started to vulcanize and composite the inner layer sealing rubber sheet 700, the outer layer sealing rubber sheet 200, the bottom cord layer 500 and the waist cord layer 600 together.

[0025] The rubber buffer seat produced by this process has less deformation in high temperature and high pressure environments, is not easy to damage, has higher durability and service life, and can meet the needs of frequent launches.

[0026] Effectively compensate for the tilt, unevenness, and subsidence of the ground during launch, ensuring the launch conditions of the launch device at launch sites with different specific pressures and unevenness and at highways above Class IV. The launch device can be launched from "pre-installed site launch" to mobile launch on vehicle-mounted roadbeds without support on Class IV highways.

[0027] like Figure 3 As shown in the figure, the 45° forward and reverse winding forming and laminating process is to firstly wrap the cord in a forward direction at 45° and laminat the waist 400 of the mold cavity 100, and then wrap the cord in a reverse direction at 45° and laminat the waist 400 of the mold cavity 100, and then perform forward and reverse cross winding until 12 layers are laminatd. The forward direction is the right direction shown in the figure, and the reverse direction is the left direction shown in the figure.

[0028] In some embodiments, both the bottom cord layer 500 and the waist cord layer 600 are made of nylon cords.

[0029] The performance of cords made of different fiber materials varies greatly. It is very important to reasonably select cord varieties and specifications to achieve comprehensive considerations in terms of strength, elongation deformation, puncture resistance, cost, and process performance. In terms of puncture resistance, a higher single cord strength and a reasonable number of layers should be selected. In terms of pressure deformation, low elongation and high modulus materials should be selected. In terms of material cost, they should have low prices and fewer layers. Rayon, nylon, and polyester are the most commonly used cord materials in China.

[0030] Strength: The single-strand strength of rayon is less than that of nylon. Even the super-strong rayon is only 18-20kgf / strand, while nylon 1260D / 2 reaches 22.5 kgf / strand. It can be seen that with the same number of strands and layers, the strength of nylon is much greater than that of rayon.

[0031] Deformation and elongation: Rayon has better dimensional stability than nylon, which is very beneficial for the product to obtain smaller pressure deformation, but not for impact deformation. Nylon is just the opposite. The larger elongation of this material can delay the impact time and reduce the impact force. In this respect, nylon has a special advantage. However, its thermal shrinkage performance and dimensional stability are poor, and thermal shrinkage brings difficulties to the process manufacturing of products. For the unfavorable factor of nylon cord, the process means of high-pressure shaping, high-pressure vulcanization and cooling shaping after vulcanization can solve the problem of large thermal shrinkage.

[0032] Tenacity and Fatigue Resistance: Rayon has poorer fatigue resistance than nylon.

[0033] Quality: The single cord of rayon 1650D / 2 and nylon 1260D / 2 is almost the same, but the specific gravity of rayon is greater than that of nylon. In addition, the strength of rayon is low, so when the strength is the same, nylon is lighter than rayon.

[0034] By comparing materials such as nylon, rayon, and polyester, the cord cord is made of nylon with a specification of 1260D / 2.

[0035] The stress state of the rubber buffer seat under the action of internal pressure is similar to that of a cylindrical thin-walled container with both ends closed. Based on the stress analysis of the thin-walled cylindrical container under internal pressure, the number of circumferential structural layers is determined by the reverse method.

[0036] According to the formula: Q = P·R (1) Q: circumferential film stress, P: ultimate pressure, R: product radius.

[0037] Given: R = 73.8 cm; P = 2.5 MPa = 25 Kgf / cm 2 Substitute into formula (1): Q = 73.8cm × 25Kgf / cm 2 =1845Kgf / cm Known 1260D / 2 cord breaking strength: ≥20.6Kgf / root, forming angle: 45° The force of a single strand during 45° winding is decomposed into: n=Cos45°×20.6Kgf / root=0.707×20.6Kgf / root=14.6Kgf / root Cord density: 10 cords / cm, i.e. cord force per centimeter: N = 146Kgf / cm Calculate the number of layers: i=Q / N=1845 / 146=11.5 layers.

[0038] Therefore, the cord layer of the rubber buffer seat molding is designed to be: 12 layers.

[0039] Forming strength check The design material is 1260D / 2 nylon cord, with a single cord strength of 231N / cord, an elongation of 21.5%, a density of 10 cords / cm, and a cord diameter of 0.65mm.

[0040] The rubber buffer seat molding process is an oblique winding structure, similar to the hose structure, and is calculated by referring to the winding hose strength calculation formula: (2) Where: P B —Compressive strength kgf / cm 2 ; N—Total number of winding wires K B —Strength of a single fiber line kgf / cm; D 计 —Calculate diameter (cm) C2 —Correction factor for different number of winding layers; C3 —Correction factor for hose The calculation formula for the number of winding wires is shown in (2): (3) Where: N 理 —Theoretical winding wire number, root; D 计 —Construction calculation diameter (mm).

[0041] α—winding angle; d—winding wire diameter, (mm).

[0042] Known D 计 =1476㎜, α=45°, d=0.65㎜, substituting the data into formula (3) yields: According to the design requirements of the rubber buffer seat, it is known that D 计 =1476㎜, K B =23.1㎏f / ㎝, C2=0.85, C3=1+21.5﹪, substitute the data into formula (2) to obtain: From the calculation, we know that 27.1㎏f / ㎝ 2 Greater than the design pressure 25㎏f / ㎝ 2 Therefore, the rubber buffer seat can withstand the design pressure according to its structure.

[0043] In some embodiments, when applying the glue, the glue is applied once to the bottom 300 of the mold cavity 100 , and twice to the waist 400 of the mold cavity 100 .

[0044] In some embodiments, the glue applied to the bottom 300 of the mold cavity 100 and the waist 400 of the mold cavity 100 is XY507 glue. XY507 glue is a single-component translucent liquid silicone rubber.

[0045] Since the flange portion 410 of the rubber buffer seat needs to be connected to the flange, in order to improve the strength of the flange portion 410. In some embodiments, an aramid reinforcement layer 800 is added to the flange portion 410 after every two layers of cords are attached.

[0046] In some embodiments, the height of the waist cord layer 600 at the flange portion 410 is 3 mm higher than the edge of the mold, so as to provide compensation for the deformation of the rubber layer during the subsequent pressing process of the punch.

[0047] In some embodiments, the inner sealing film 700 is covered with an electromagnetic shielding layer, which plays a role in shielding electromagnetic radiation.

[0048] In some embodiments, the waist cord layer 600 is staggered and connected with the bottom cord layer 500 to improve the connection performance between the waist cord layer 600 and the bottom cord layer 500.

[0049] In some embodiments, the adhesive for bonding the outer sealing film 200 and the inside of the mold cavity 100 is a bulk adhesive made by dissolving nitrile-polyvinyl chloride, and the adhesive for bonding the outer sealing film 200 and the waist cord layer 600 and the bottom cord layer 500 is a bulk adhesive made by dissolving nitrile-polyvinyl chloride.

[0050] The main rubber material of the rubber buffer seat is a nitrile-polyvinyl chloride blended rubber, and the adhesive liquid for bonding the inner and outer rubber plates is mainly nitrile with a matching design of a meta- and methyl methacrylate bonding system.

[0051] In some embodiments, the adhesive connecting two adjacent bottom cord layers 500 is a bulk adhesive made of nitrile rubber-natural rubber, and the adhesive connecting two adjacent waist cord layers 600 is a bulk adhesive made of nitrile rubber-natural rubber.

[0052] The adhesive glue is made by dissolving nitrile rubber and natural rubber. The main body of the adhesive is nitrile rubber, and a small amount of natural rubber acts as a plasticizer and tackifier in the nitrile rubber. In the formula design, the combined system of (resorcinol) methyl (hexamethylenetetramine accelerator H) white (white carbon black) is used as the bonding system, and a certain amount of resin is added as a tackifier. The post-curing system is also selected. The adhesion performance test and the finished product performance test prove that the adhesion is firm and the adhesive glue performance is reliable.

[0053] The rubber buffer seat is a composite thick-walled product made of multiple layers of nylon cords. Due to the high strength and large shrinkage of nylon, the inner capsule is used for high-pressure shaping and vulcanization to solve the problem of large deformation of the outer dimensions of the rubber buffer seat after vulcanization. Since rubber is a poor conductor of heat, for thick-walled products, it is difficult to make the inner and outer layers of rubber reach the vulcanization flat line range at the same time by high-temperature vulcanization, so it is advisable to use a low temperature of 143°C during vulcanization.

[0054] The rubber buffer seat body has many thick layers and a complex structure, and its vulcanization pressure should be increased accordingly to prevent bubbles from being generated in the product during the vulcanization process, improve the density of the rubber material and the adhesion between the rubber cord layers, prevent the outer sealing rubber sheet 200, the bottom cord layer 500, the waist cord layer 600 and the inner sealing rubber sheet 700 from delamination, improve the physical and mechanical properties of the inner and outer rubbers and the product appearance quality, and fundamentally improve and enhance the product quality.

[0055] In the trial production, by balancing and adjusting the vulcanization speed and vulcanization flat range of the inner layer sealing rubber sheet 700 and the bottom and waist cord layer 600, the inner and outer layer sealing rubber sheets 200 and the bottom and waist cord layer 600 reach equivalent vulcanization degree. According to the positive vulcanization condition of the inner rubber of 151℃×28min, the vulcanization temperature coefficient of the rubber is known to be 1.86, and the vulcanization time at 151℃ is 28min. It is required that when the temperature is 143℃, the vulcanization time should be adjusted to achieve equivalent vulcanization, and calculated according to the vulcanization effect formula: E= I1·t Where: E—Sulfurization effect I1—Vulcanization strength t—vulcanization time According to the vulcanization strength table: when T=151℃, I1=23.7, then Sulfurization effect E = I1·t = 23.7×28=663.6 Calculated according to the conversion formula of equivalent vulcanization time: H=E / I2 Where: E—Sulfurization effect I2—Vulcanization strength To adjust the temperature to 143°C, look up the table and get I2=12.0. Substitute it into the above formula, and the equivalent vulcanization time is H=E / I2=663.6 / 12=55.3min, so the vulcanization conditions are 143°C and 55.3 minutes.

[0056] It is known that the positive vulcanization conditions of the rubber compound are 143℃×55.3min, the heat conduction time of the rubber compound vulcanization is K1=2.5min, the calculated thickness of the rubber layer is δ=2.5㎜, the heat conduction time of each layer of cord is K2=3.2min, the number of cord layers i=12 layers, the heating time is 50min, and the cooling time is 30min. According to the vulcanization time calculation formula: H1=C+K1δ+K2i Where: C—Positive vulcanization time of rubber K1—rubber vulcanization heat conduction time K2—heat conduction time of each layer of cord i—number of cord layers δ—Calculated thickness of adhesive layer Substituting the known data into the formula H1=C+K1δ+K2i, we get: H1=C+K1δ+K2i=55.3+2.5×2.5+3.2×12=99.95min≈100min H 总 = H1+H2 Where: H 总 —Total vulcanization time of rubber buffer seat H1—Positive vulcanization time of rubber buffer seat H2—Heating and cooling time Substitute the known data into formula H 总 = H1 + H2: The total vulcanization time of the rubber buffer seat is H 总 = H1+H2=100+50+30=180min The vulcanization conditions of the rubber buffer seat are: 143℃×100 min.

[0057] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0058] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present application.

Claims

1. A rubber buffer seat manufacturing process, characterized in that: The following steps are involved: Apply glue liquid in the mold cavity; Lay the cut outer sealing film flat on the workbench and apply glue; After the glue on the outer sealing film is dry, the outer sealing film covering the bottom and waist of the mold cavity is attached to the inside of the mold cavity and compacted; Twelve bottom cord layers are bonded to the outer sealing film at the position corresponding to the bottom of the mold cavity by glue, wherein the first two bottom cord layers are arranged in a cross-staggered manner, and the third to tenth bottom cord layers are bonded in a staggered manner in a cross-shaped pattern, and two adjacent bottom cord layers are connected by glue; The waist cord layer is bonded to the position of the waist of the mold cavity on the outer sealing film by glue. The waist cord layer adopts a 45° positive and negative winding molding and bonding process, one positive and one negative bonding, a total of 12 layers of cords are bonded, and the adjacent two waist cord layers are connected by glue; Lay the cut inner sealing film flat on the workbench and apply glue; After the glue on the inner sealing film is dry, the inner sealing film is used to cover the bottom cord layer and the waist cord layer and compacted; The convex mold is pressed down into the mold cavity for compaction, and then the vulcanization process is started to vulcanize and compound the inner sealing film, the outer sealing film, the bottom cord layer and the waist cord layer together.

2. The rubber buffer seat manufacturing process according to claim 1 is characterized in that: When applying glue, apply one coat of glue on the bottom of the mold cavity and two coats of glue on the waist of the mold cavity.

3. The rubber buffer seat manufacturing process according to claim 3 is characterized in that: The glue applied to the bottom and waist of the mold cavity is XY507 glue.

4. The manufacturing process of the rubber buffer seat according to claim 1 is characterized in that: Add an aramid reinforcement layer after every two layers of cord are bonded at the flange.

5. The manufacturing process of the rubber buffer seat according to claim 4 is characterized in that: The height of the waist cord layer at the flange is 3 mm higher than the edge of the mold.

6. The manufacturing process of the rubber buffer seat according to claim 1 is characterized in that: The waist cord layer is connected in an alternating manner with the bottom cord layer.

7. The manufacturing process of the rubber buffer seat according to claim 1, characterized in that: The adhesive for bonding the outer sealing film to the inside of the mold cavity is a bulk adhesive made by dissolving nitrile-polyvinyl chloride, and the adhesive for bonding the inner sealing film to the waist cord layer and the bottom cord layer is a bulk adhesive made by dissolving nitrile-polyvinyl chloride.

8. The manufacturing process of the rubber buffer seat according to claim 1, characterized in that: The adhesive liquid connecting two adjacent bottom cord layers is a bulk adhesive liquid made by dissolving nitrile rubber-natural rubber, and the adhesive liquid connecting two adjacent waist cord layers is a bulk adhesive liquid made by dissolving nitrile rubber-natural rubber.

9. The manufacturing process of the rubber buffer seat according to claim 1, characterized in that: The bottom cord layer and the waist cord layer both use nylon cords.

10. The manufacturing process of the rubber buffer seat according to claim 1, characterized in that: The inner sealing film is covered with an electromagnetic shielding layer.

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