A superfine bicomponent fiber composite needled felt and its preparation process

Abstract

This invention discloses an ultrafine bicomponent fiber composite needled felt and its preparation process, comprising a needled felt body, wherein the needled felt body is composed of a base layer forming the bottom layer, and a wear-resistant layer is provided on the surface of the needled felt body. A high-temperature resistant layer is provided on the top of the base layer, and a corrosion-resistant layer is provided at the bottom of the wear-resistant layer. A flame-retardant layer is provided between the corrosion-resistant layer and the high-temperature resistant layer. In the preparation process of this ultrafine bicomponent fiber composite needled felt and its preparation process, mixed fibers and ultrafine PSPA island fibers are added to improve wear resistance. The addition of a silicate cement polystyrene foam slurry layer, ultrafine glass fiber composite filter material, reinforcing layer, and aramid fiber layer increases the overall high-temperature resistance of the needled felt. Furthermore, the addition of PTFE fiber and polytetrafluoroethylene coating layers improves corrosion resistance. Simultaneously, the knitted aluminosilicate fiber and PPS fiber layers enhance the flame retardancy of the needled felt, thereby improving the overall performance of the needled felt.

Description

Technical Field

[0001] This invention relates to the field of needle-punched felt technology, specifically to an ultrafine bicomponent fiber composite needle-punched felt and its preparation process. Background Technology

[0002] Needle-punched felt is a common type of filter cloth, and there are many varieties due to different performance characteristics. Ultrafine bicomponent fiber composite needle-punched felt is one of them. Ultrafine bicomponent fiber composite needle-punched felt is mainly composed of a base fabric layer and micron-level ultrafine denier fiber layers attached to the upper and lower surfaces of the base fabric layer. These fiber layers include polyester fibers, orange-petal-shaped PA / PET bicomponent fibers that have been mechanically opened to obtain micron-level ultrafine denier fibers, and fine denier acrylic fibers that are intertwined and bound together with these fibers to form micro-dense pores. This structural design aims to improve the overall thermal stability of the product and effectively intercept fine particulate dust, improve dust filtration accuracy, and achieve the goal of energy saving and low emission.

[0003] A novel ultrafine bicomponent fiber composite needle-punched felt, disclosed in publication number CN208965189U, improves the overall thermal stability of the product and reduces its thermal shrinkage rate by mixing a certain proportion of fine denier acrylic fibers into orange-petal-shaped PA / PET bicomponent fibers. This prevents shrinkage from causing blockage of the internal micropores and reducing air permeability. The mixed fibers are then carded with fine-gauge needle cloth using a specific carding machine, and needled with fine-gauge needles and a suitable needle-punching frequency. This process opens the orange-petal-shaped bicomponent fibers, resulting in micron-level ultrafine denier fibers that entangle with the other two types of fibers to form dense micropores. This ensures effective flue gas passage, reduces operating resistance, and provides excellent filtration for fine dust. Furthermore, the mechanical fiber opening process using carding and needle punching also saves time and energy.

[0004] However, the above solution still has the following problems in use: When high-temperature substances are emitted and pass through the needle-punched felt, the filtration efficiency of the needle-punched felt will be affected. Over time, the high temperature will damage the structural integrity of the needle-punched felt and harmful gases will corrode it. When the discharge volume is large, the friction between the needle-punched felt and the emitted substances is heavy, which will also easily cause wear to the needle-punched felt, thereby shortening its service life. Therefore, it is necessary to enhance the high-temperature resistance and wear resistance of the needle-punched felt.

[0005] Therefore, we propose an ultrafine bicomponent fiber composite needled felt and its preparation process to solve the problems mentioned above. Summary of the Invention

[0006] The purpose of this invention is to provide an ultrafine bicomponent fiber composite needled felt and its preparation process, in order to solve the problems mentioned in the background art. Currently available needled felts on the market have the following issues: during use, when high-temperature substances are emitted and pass through the needled felt, the stability of the needled felt structure is damaged. Furthermore, when the emission volume is large, the friction between the needled felt and the emitted substances is heavy, which can easily cause wear to the needled felt and thus shorten its service life.

[0007] To achieve the above objectives, the present invention provides the following technical solution: an ultrafine bicomponent fiber composite needled felt, comprising a needled felt body, wherein the needled felt body is composed of a base layer forming a bottom layer, and a wear-resistant layer is provided on the surface of the needled felt body, a high-temperature resistant layer is provided on the top of the base layer, a corrosion-resistant layer is provided on the bottom of the wear-resistant layer, and a flame-retardant layer is provided between the corrosion-resistant layer and the high-temperature resistant layer.

[0008] Preferably, the base layer is woven from polyester fiber, PET fiber and fine denier acrylic fiber, and the polyester fiber, PET fiber and fine denier acrylic fiber are twisted into a single bundle and needle-punched together.

[0009] Preferably, the wear-resistant layer is mainly composed of mixed fibers and ultrafine PSPA island fibers, with the ultrafine PSPA island fibers interlaced on the outside of the mixed fibers, and the mixed fibers are distributed longitudinally at equal intervals.

[0010] Preferably, the mixed fiber is woven from three strands of polyester fiber, aramid fiber and acrylic fiber, and the ultrafine PSPA sponge fiber on the outer side of the mixed fiber is arranged in a wavy shape.

[0011] Preferably, the corrosion-resistant layer is woven from PTFE fibers, and a polytetrafluoroethylene coating layer is provided on the surface of the PTFE fibers.

[0012] Preferably, the high-temperature resistant layer is configured as a double-layer structure, and each layer consists of a silicate cement polystyrene foam slurry layer and an ultra-fine glass fiber composite filter material. The ultra-fine glass fiber composite filter material is woven in a cross-hatching pattern, and the outer side of the ultra-fine glass fiber composite filter material is covered with a silicate cement polystyrene foam slurry layer. Furthermore, annular reinforcing layers are fixed at equal intervals on the opposite surfaces of the upper and lower silicate cement polystyrene foam slurry layers, and the upper and lower reinforcing layers are connected together by a double row of aramid fiber layers.

[0013] Preferably, the reinforcing layer is woven from ceramic fibers and polyimide fibers in a diamond pattern, and both the ceramic fibers and polyimide fibers are double-threaded and combed twice simultaneously, forming a web that is laid on both the top and bottom simultaneously.

[0014] Preferably, the flame-retardant layer is a fiber web formed by the entanglement of aluminum silicate fiber and PPS fiber layer, and the aluminum silicate fiber and PPS fiber layer improve the overall flame-retardant performance of the needle-punched felt.

[0015] A preparation process for an ultrafine bicomponent fiber composite needled felt includes the following steps:

[0016] I. Raw material preparation:

[0017] ① Select high-quality polyester fiber, PET grade fiber, fine denier acrylic fiber, etc. as basic raw materials, and carry out necessary pretreatment, such as washing and drying;

[0018] ② Preparation of other high-performance materials:

[0019] Combing of polyester fiber, aramid fiber, and acrylic fiber filaments;

[0020] Preparation of silicate cement polystyrene foam slurry layer, combing of ultrafine glass fiber composite filter material, and double combing and double laying of ceramic fiber and polyimide fiber;

[0021] Carding of aluminum silicate fiber and PPS fiber layers;

[0022] II. Fiber Mixing and Carding:

[0023] Various fiber raw materials are mixed in a certain proportion and then combed through a carding machine to make the fibers arrange in parallel and remove impurities and short fibers, forming a uniform fiber web.

[0024] Polyester fiber, aramid fiber, and acrylic fiber filaments are combed and laid out simultaneously using a three-combing and three-laying method.

[0025] A polytetrafluoroethylene coating is applied to the surface of PTFE fibers;

[0026] A silicate cement polystyrene foam slurry layer is coated on the outside of the ultrafine glass fiber composite filter material, and ceramic fibers and polyimide fibers are combed and laid in a double-combed double-lay method.

[0027] It is made of combed and interwoven layers of aluminosilicate fiber and PPS fiber;

[0028] III. Knitted reinforcement:

[0029] The combed fibers are fed into a needle punching machine for needle punching reinforcement. During the needle punching process, the needles on the needle plate repeatedly puncture the fiber tissue, causing the fibers to entangle and bind together, forming a stable three-dimensional connection structure, thereby improving the high temperature resistance, wear resistance, corrosion resistance and flame retardant properties of the needle-punched felt.

[0030] IV. Heat setting and post-treatment:

[0031] After needle reinforcement, the needle-punched felt needs to undergo heat setting to stabilize its structure and performance. Subsequently, other post-processing techniques, such as calendering and trimming, can be performed as needed to further improve the quality and appearance of the product.

[0032] Compared with the prior art, the beneficial effects of the ultrafine bicomponent fiber composite needled felt and its preparation process of the present invention are as follows:

[0033] 1. The high-temperature resistant layer, silicate cement polystyrene foam slurry layer, and ultra-fine glass fiber composite filter material have good high-temperature and corrosion resistance. The ceramic fiber and polyimide fiber are mixed in a certain proportion to obtain high-temperature resistant material. The aramid fiber layer has high-temperature resistance and high-temperature thermal stability, as well as a certain degree of chemical resistance, which improves the high-temperature resistance of the needle-punched felt.

[0034] 2. By using a wear-resistant layer, mixed fibers and ultra-fine PSPA island fibers are combined to produce a needle-punched felt with a limiting oxygen index of ≥42%, good dust capture effect, high tensile strength, and good wear resistance. It is made of polyester fiber, aramid fiber and acrylic fiber filaments, which improves the wear resistance of the needle-punched felt, reduces wear and increases service life.

[0035] 3. By setting a corrosion-resistant layer, a polytetrafluoroethylene (PTFE) coating layer is set on the outside of the fiber layer. The PTFE coating layer has the characteristics of being resistant to acids and alkalis and almost insoluble in all solvents, which improves the corrosion resistance of the needle-punched felt. The PTFE fiber layer has high corrosion resistance.

[0036] 4. The flame-retardant layer, formed by the intertwining of aluminum silicate fiber and PPS fiber layer, improves the overall flame-retardant effect of the needle-punched felt. The PPS fiber layer has excellent flame-retardant properties, high temperature resistance and non-hydrolysis, thereby improving the flame-retardant performance of the needle-punched felt and preventing combustion at high temperatures. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the overall structure of the needle-punched felt of the present invention;

[0038] Figure 2 This is a schematic diagram of the basic organizational structure of the present invention;

[0039] Figure 3 This is a schematic diagram of the wear-resistant layer structure of the present invention;

[0040] Figure 4 This is a schematic diagram of the mixed fiber structure of the present invention;

[0041] Figure 5 This is a schematic diagram of the corrosion-resistant layer structure of the present invention;

[0042] Figure 6 This is a schematic diagram of the high-temperature resistant layer structure of the present invention;

[0043] Figure 7 This is a schematic diagram of the structure of the silicate cement polystyrene foam slurry layer and ultrafine glass fiber composite filter material of the present invention;

[0044] Figure 8 This is a schematic diagram of the distribution structure of the reinforcing layer and the aramid fiber layer of the present invention;

[0045] Figure 9 This is a schematic diagram of the reinforcing layer structure of the present invention;

[0046] Figure 10 This is a schematic diagram of the flame-retardant layer structure of the present invention.

[0047] In the diagram: 1. Needle-punched felt body; 2. Base layer; 201. Polyester fiber; 202. PET fiber; 203. Fine denier acrylic fiber; 3. Wear-resistant layer; 301. Mixed fiber; 3011. Polyester fiber; 3012. Aramid fiber; 3013. Acrylic fiber filament; 302. Ultrafine PSPA island fiber; 4. Corrosion-resistant layer; 401. PTFE fiber; 402. Polytetrafluoroethylene coating layer; 5. High-temperature resistant layer; 501. Silicate cement polystyrene foam slurry layer; 502. Ultrafine glass fiber composite filter material; 503. Reinforcing layer; 5031. Ceramic fiber; 5032. Polyimide fiber; 504. Aramid sulfone fiber layer; 6. Flame retardant layer; 601. Alumina silicate fiber; 602. PPS fiber layer. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0049] Please refer to Figure 1 - Figure 10 As shown, an ultrafine bicomponent fiber composite needled felt includes a needled felt body 1, which is composed of a base layer 2 forming the bottom layer. The surface of the needled felt body 1 is provided with a wear-resistant layer 3, the top of the base layer 2 is provided with a high-temperature resistant layer 5, the bottom of the wear-resistant layer 3 is provided with a corrosion-resistant layer 4, and a flame-retardant layer 6 is provided between the corrosion-resistant layer 4 and the high-temperature resistant layer 5. The base layer 2 is woven from polyester fiber 201, PET fiber 202 and fine denier acrylic fiber 203, and the polyester fiber 201, PET fiber 202 and fine denier acrylic fiber 203 are wound into a single bundle and needled together.

[0050] like Figure 1 - Figure 2As shown, firstly, the components of the needle-punched felt are briefly introduced. The needle-punched felt body 1 consists of a base layer 2, a high-temperature resistant layer 5, a flame-retardant layer 6, a corrosion-resistant layer 4, and a wear-resistant layer 3 from the inside out. The base layer 2 is woven with polyester fiber 201, PET fiber 202, and fine denier acrylic fiber 203 as the basic textile units, and the base needle-punched felt bottom layer is formed by horizontal weaving.

[0051] Example 1: To improve the overall wear resistance of needle-punched felt, the following solution is proposed. Please refer to the following for details. Figure 1 and Figure 3 - Figure 4 As shown,

[0052] The wear-resistant layer 3 is mainly composed of mixed fibers 301 and ultrafine PSPA island fibers 302. The ultrafine PSPA island fibers 302 are interwoven on the outside of the mixed fibers 301, and the mixed fibers 301 are distributed longitudinally at equal intervals. The mixed fibers 301 are woven from three strands of polyester fiber 3011, aramid fiber 3012 and acrylic fiber filament 3013. The ultrafine PSPA sponge fibers 302 on the outside of the mixed fibers 301 are arranged in a wavy shape.

[0053] By using a combination of blended fiber 301 and ultrafine PSPA island fiber 302, a needle-punched felt with a limiting oxygen index of ≥42%, good dust capture effect, and high tensile strength was obtained, resulting in good wear resistance of the needle-punched felt body 1. In addition, polyester fiber 3011, aramid fiber 3012 and acrylic fiber filament 3013 all have good wear resistance, which improves the wear resistance of the needle-punched felt, reduces wear, and increases service life.

[0054] Example 2: To improve the overall high-temperature resistance of needle-punched felt, the following solution is proposed. Please refer to the following for details. Figure 1 and Figure 6 - Figure 9 As shown,

[0055] The high-temperature resistant layer 5 is configured as a double-layer structure, and each layer consists of a silicate cement polystyrene foam slurry layer 501 and an ultra-fine glass fiber composite filter material 502. The ultra-fine glass fiber composite filter material 502 is woven in a cross pattern, and the outer side of the ultra-fine glass fiber composite filter material 502 is covered with the silicate cement polystyrene foam slurry layer 501. Annular reinforcing layers 503 are fixed at equal intervals on the opposite surfaces of the upper and lower silicate cement polystyrene foam slurry layers 501. The upper and lower reinforcing layers 503 are connected together by a double row of aramid fiber layers 504. The reinforcing layer 503 is woven in a diamond pattern by ceramic fibers 5031 and polyimide fibers 5032. Both ceramic fibers 5031 and polyimide fibers 5032 are double-threaded and combed twice at the same time, and the upper and lower layers are laid out simultaneously.

[0056] The prepared silicate cement polystyrene foam slurry layer 501 is laid on the outside of the ultrafine glass fiber composite filter material 502. After being fused and fixed, it forms the outer structure. Ceramic fiber 5031 and polyimide fiber 5032 are woven to form connecting nodes. Then, the upper and lower structures are fixed together by the aramid fiber layer 504. While having a certain chemical resistance, it also improves the high temperature resistance of the needle-punched felt.

[0057] Example 2: To improve the overall corrosion resistance and flame retardant properties of needle-punched felt, the following solution is proposed. Please refer to the following for details. Figure 1 , Figure 4 and Figure 10 As shown,

[0058] The corrosion-resistant layer 4 is woven from PTFE fibers 401, and a polytetrafluoroethylene coating layer 402 is provided on the surface of the PTFE fibers 401; the flame-retardant layer 6 is a fiber web formed by intertwining aluminum silicate fibers 601 and PPS fiber layer 602, and the aluminum silicate fibers 601 and PPS fiber layer 602 improve the overall flame-retardant performance of the needle-punched felt.

[0059] A polytetrafluoroethylene (PTFE) coating layer 402 is applied to the outside of the PTFE fiber 401. The PTFE coating layer 402 has the characteristics of being resistant to acids and alkalis and almost insoluble in all solvents, which improves the corrosion resistance of the needle-punched felt body 1. The PTFE fiber 401 has high corrosion resistance. The fiber web formed by the intertwining of the aluminum silicate fiber 601 and the PPS fiber layer 602 serves as a fiber layer, which improves the overall flame retardant effect of the needle-punched felt body 1. The PPS fiber layer 602 has excellent flame retardant properties, high temperature resistance, and non-hydrolysis, thereby improving the flame retardant properties of the needle-punched felt body 1 and preventing combustion at high temperatures.

[0060] A preparation process for an ultrafine bicomponent fiber composite needled felt includes the following steps:

[0061] I. Raw material preparation:

[0062] ① Select high-quality polyester fiber 201, PET fiber 202, fine denier acrylic fiber 203, etc. as basic raw materials, and carry out necessary pretreatment, such as washing and drying;

[0063] ② Preparation of other high-performance materials:

[0064] Polyester fiber 3011, aramid fiber 3012, acrylic fiber filament 3013 combed;

[0065] The process involves mixing silicate cement polystyrene foam slurry layer 501, combing ultrafine glass fiber composite filter material 502, and double-combing and double-laying ceramic fiber 5031 and polyimide fiber 5032.

[0066] Aluminosilicate fiber 601 and PPS fiber layer 602 combing;

[0067] II. Fiber Mixing and Carding:

[0068] Various fiber raw materials are mixed in a certain proportion and then combed through a carding machine to make the fibers arrange in parallel and remove impurities and short fibers, forming a uniform fiber web.

[0069] Polyester fiber 3011, aramid fiber 3012, and acrylic fiber 3013 are combed and laid out simultaneously using a three-combing, three-lay method.

[0070] A polytetrafluoroethylene coating layer 402 is coated on the surface of PTFE fiber 401;

[0071] The silicate cement polystyrene foam slurry layer 501 is coated on the outside of the ultra-fine glass fiber composite filter material 502. The ceramic fiber 5031 and polyimide fiber 5032 are combed and laid in a double-combed double-lay method.

[0072] It is made of combed and interwoven aluminum silicate fiber 601 and PPS fiber layer 602;

[0073] III. Knitted reinforcement:

[0074] The combed fibers are fed into a needle punching machine for needle punching reinforcement. During the needle punching process, the needles on the needle plate repeatedly puncture the fiber tissue, causing the fibers to entangle and bind together, forming a stable three-dimensional connection structure, thereby improving the high temperature resistance, wear resistance, corrosion resistance and flame retardant properties of the needle-punched felt.

[0075] IV. Heat setting and post-treatment:

[0076] After needle reinforcement, the needle-punched felt needs to undergo heat setting to stabilize its structure and performance. Subsequently, other post-processing techniques, such as calendering and trimming, can be performed as needed to further improve the quality and appearance of the product.

[0077] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0078] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0079] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" or "linked" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0080] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An ultrafine bicomponent fiber composite needle felt comprising a needle felt body (1), characterized in that: The needle felt body (1) is composed of a base layer (2) as a bottom layer, the base layer (2) is woven by polyester fibers (201), PET fibers (202) and fine denier acrylic fibers (203), and the three kinds of polyester fibers (201), PET fibers (202) and fine denier acrylic fibers (203) are twisted into a single bundle and connected by needle punching, and the surface of the needle felt body (1) is provided with a wear-resistant layer (3), the wear-resistant layer (3) is mainly composed of mixed fibers (301) and ultra-fine PSPA sea-island fibers (302), the ultra-fine PSPA sea-island fibers (302) are interlaced and woven on the outer side of the mixed fibers (301) up and down, and the mixed fibers (301) are distributed in longitudinal equal intervals, the mixed fibers (301) are composed of three kinds of polyester fibers (3011), aramid fibers (3012) and acrylic fiber filaments (3013), and the ultra-fine PSPA sea-island fibers (302) on the outer side of the mixed fibers (301) are arranged in a wave shape, a high-temperature-resistant layer (5) is arranged on the top of the base layer (2), the high-temperature-resistant layer (5) is arranged as a double-layer structure, and each layer structure is composed of a silicate cement polystyrene foam slurry layer (501) and an ultra-fine glass fiber composite filter material (502), the ultra-fine glass fiber composite filter material (502) is crosswise interlaced, the outer side of the ultra-fine glass fiber composite filter material (502) is covered with the silicate cement polystyrene foam slurry layer (501), and the opposite surfaces of the upper and lower silicate cement polystyrene foam slurry layers (501) are fixed with annular reinforcing layers (503) at equal intervals, and the upper and lower reinforcing layers (503) are connected together by double rows of aramid fiber layers (504), a corrosion-resistant layer (4) is arranged at the bottom of the wear-resistant layer (3), the corrosion-resistant layer (4) is woven by PTFE fibers (401), a polytetrafluoroethylene film layer (402) is arranged on the surface of the PTFE fibers (401), and a flame-retardant layer (6) is arranged between the corrosion-resistant layer (4) and the high-temperature-resistant layer (5).

2. An ultra-fine bicomponent fiber composite needle-punched felt according to claim 1, characterized in that: The reinforcing layer (503) is connected and woven in a diamond shape by ceramic fibers (5031) and polyimide fibers (5032), and the ceramic fibers (5031) and the polyimide fibers (5032) are both double-line parallel and are carded twice at the same time, and are formed by laying the web up and down at the same time.

3. An ultra-fine bicomponent fiber composite needle-punched felt according to claim 1, characterized in that: The flame-retardant layer (6) is a fiber web formed by intertangling aluminum silicate fibers (601) and PPS fiber layers (602), and the aluminum silicate fibers (601) and the PPS fiber layers (602) improve the flame-retardant performance of the whole needle felt.

4. A process for the production of a fine bicomponent fiber composite needle felt according to any one of claims 1 to 3, characterized in that: The method comprises the following steps: I. Raw material preparation: ①, select high-quality polyester fibers (201), PET fibers (202) and fine denier acrylic fibers (203) as basic raw materials and pretreat them; ②, preparation of other high-performance materials: carding of polyester fibers (3011), aramid fibers (3012) and acrylic fiber filaments (3013); Silicate cement polystyrene foam slurry layer (501) mixed preparation, superfine glass fiber composite filter material (502) carding, ceramic fiber (5031) and polyimide fiber (5032) double comb double paving; Aluminum silicate fiber (601) and PPS fiber layer (602) carding; Second, fiber mixing and carding: After mixing various fiber raw materials in a certain proportion, carding machine is used for carding to make fibers parallel arrangement and remove impurities and short fibers, forming a uniform fiber web; Polyester fiber (3011), aramid fiber (3012) and acrylic fiber (3013) are carded by three combing and three paving method at the same time; PTFE fiber (401) is coated with a polytetrafluoroethylene film layer (402) on its surface; Silicate cement polystyrene foam slurry layer (501) is coated on the outside of superfine glass fiber composite filter material (502), ceramic fiber (5031) and polyimide fiber (5032) are carded by double combing and double paving at the same time; Aluminum silicate fiber (601) and PPS fiber layer (602) are carded and interwoven to form a fabric; Third, needle punching reinforcement: The carded fibers are sent to the needle punching machine for needle punching reinforcement. During the needle punching process, the needle on the needle plate repeatedly penetrates the fiber tissue, causing the fibers to entangle and adhere to each other, forming a stable three-dimensional connection structure, thereby improving the high temperature resistance, wear resistance, corrosion resistance and flame retardant performance of the needle punching felt; Fourth, heat setting and post-processing: The needle punching felt after needle punching reinforcement needs to be heat set to stabilize its structure and performance, and then post-processing is carried out to further improve the quality and appearance of the product.

Images