Composite gasket for severe corrosion service

Abstract

The utility model belongs to the field of sealing gasket, specifically disclose a kind of composite sealing gasket for strong corrosion working condition, including metal framework and PEEK cladding, the metal framework is equipped with several through holes, the PEEK cladding is connected in the side with metal framework and medium contact by several through holes.The utility model passes through metal framework as reinforcing structure, can effectively promote the compression strength and anti creep of composite sealing gasket, can provide elasticity for composite sealing gasket, and PEEK is as engineering plastics, with excellent high temperature resistance and corrosion resistance, can provide sealing layer for composite sealing gasket, the combination of two can make composite sealing gasket be used in high temperature, high pressure, strong corrosion working condition, its long-term use temperature can reach 250 DEG C, far more than all rubber-made sealing gasket, even better than the sealing gasket made of PTFE material.

Description

Technical Field

[0001] This utility model belongs to the field of sealing gaskets, specifically relating to a composite sealing gasket for use in highly corrosive environments. Background Technology

[0002] Gaskets are essential components in mechanical equipment and pipeline connections, widely used in petrochemicals, automotive manufacturing, aerospace, hydraulic systems, and household appliances. Their core function is to fill the microscopic gaps between two stationary connection surfaces, preventing leakage of internal media (liquid or gas) and intrusion of external contaminants, ensuring the system's sealing integrity, operating efficiency, and safety. Gaskets are also a key component of plate heat exchangers, their performance directly determining the sealing reliability, operating efficiency, and service life of the plate heat exchanger. However, current gaskets on the market have significant limitations:

[0003] 1. Long-term operating temperature usually has a certain upper limit. For example, the temperature of gaskets made of EPDM material is about 150-160℃. When the temperature exceeds its tolerance range, the gasket is prone to hardening, loss of elasticity, or even decomposition, resulting in the failure of the gasket's sealing performance.

[0004] 2. In corrosive conditions such as strong acids, strong alkalis, and organic solvents, gaskets may swell, corrode, or degrade. This not only leads to the failure of the gasket's sealing performance but may also contaminate the internal process medium.

[0005] 3. Under long-term continuous pre-tightening force, the gasket will undergo irreversible deformation, that is, permanent compression deformation, which will lead to a decrease in the sealing performance of the gasket and cause leakage when there are temperature or pressure fluctuations. Utility Model Content

[0006] The purpose of this invention is to solve the above-mentioned problems by providing a composite sealing gasket for use in highly corrosive environments. This composite sealing gasket is resistant to high temperatures, oil, and chemical corrosion, and also has the characteristics of high pressure resistance and creep resistance.

[0007] To achieve the above objectives, this utility model provides a composite sealing gasket for highly corrosive working conditions, comprising a metal skeleton and a PEEK coating layer. The metal skeleton is provided with several through holes, and the PEEK coating layer is connected to the side of the metal skeleton that is in contact with the medium through several through holes.

[0008] As a further optimization, the PEEK coating layer is divided into an outer PEEK coating layer and an inner PEEK coating layer, which are connected to opposite sides of the metal skeleton through several through holes.

[0009] As a further optimization, the PEEK coating layer forms an anchoring structure with the metal skeleton by injecting molten PEEK material into several through holes under high pressure.

[0010] As a further optimization, the composite sealing gasket is a composite sealing gasket for plate heat exchangers. The composite sealing gasket includes a gasket body consisting of two primary sealing areas, two primary flow channel corner hole areas, and two secondary sealing areas. The two primary flow channel corner hole areas in the gasket body are laterally provided with secondary flow channel corner hole areas. The secondary flow channel corner hole areas are connected to the secondary sealing areas through connecting ribs. The through holes on the metal skeleton at the two primary sealing areas are large and dense, while the through holes on the metal skeleton at the two primary flow channel corner hole areas and the two secondary flow channel corner hole areas are small and sparse.

[0011] Advantages and beneficial effects of this utility model

[0012] 1. The composite sealing gasket in this utility model is composed of a metal skeleton and a PEEK coating layer. The metal skeleton, as a reinforcing structure, can effectively improve the compressive strength and creep resistance of the composite sealing gasket and provide elasticity. PEEK, as an engineering plastic, has excellent high temperature resistance and corrosion resistance and can provide a sealing layer for the composite sealing gasket. The combination of the two allows the composite sealing gasket to be used in high temperature, high pressure and highly corrosive working conditions. Its long-term service temperature can reach 250℃, which is far superior to all sealing gaskets made of rubber and even better than sealing gaskets made of PTFE material.

[0013] 2. In this utility model, the PEEK coating layer covers both the inner and outer sides of the metal frame, namely the outer PEEK coating layer and the inner PEEK coating layer. The inner PEEK coating layer can effectively isolate the internal medium from contact with the metal frame. Even in the event of accidental leakage, the outer PEEK coating layer can effectively protect the metal frame from corrosion.

[0014] 3. This utility model injects molten PEEK material into several through holes under high pressure to form an anchoring structure with the metal skeleton. The anchoring structure can make the PEEK outer cladding, PEEK inner cladding and metal skeleton form an integrated composite structure, thus making the overall compressive strength stronger and the stability better.

[0015] 4. The composite sealing gasket in this utility model has unparalleled resistance to organic solvents, strong acids (such as concentrated sulfuric acid and hydrochloric acid), strong alkalis, oxidants, etc., making it the first choice for highly corrosive chemical media conditions. It solves the problem of swelling, corrosion or degradation of traditional rubber gaskets under corrosive conditions, and avoids sealing failure and contamination of the process medium by external pollutants after failure.

[0016] 5. The composite sealing gasket in this utility model will not experience "cold flow" (creep) like traditional rubber gaskets under high temperature and high pressure, and can maintain stable sealing performance. It will not cause leakage when there are temperature or pressure fluctuations, and has a long service life.

[0017] 6. In this utility model, the composite sealing gasket adjusts the size and density of the through holes on the metal frame according to the different pressures of the plates. In areas with relatively low pressure relative to the plates, i.e., the first sealing area of ​​the composite sealing gasket, the through holes on the metal frame are designed to be large and dense. In areas with relatively high pressure relative to the plates, i.e., the first and second flow channel corner hole areas at both ends of the composite sealing gasket, the through holes on the metal frame are designed to be small and sparse. Therefore, by adjusting the density and size of the through holes on the metal frame, the overall pressure of the composite sealing gasket can be balanced, avoiding the risk of medium leakage caused by uneven force leading to local compression over-extension and gaps. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the composite sealing gasket in the plate heat exchanger provided in this embodiment of the utility model;

[0020] Figure 2 This is provided by the embodiment of the present utility model. Figure 1 Enlarged view of point A in the middle;

[0021] Figure 3 This is provided by the embodiment of the present utility model. Figure 1 Enlarged view of point B in the middle;

[0022] Figure 4 This is provided by the embodiment of the present utility model. Figure 3 Enlarged view of point C in the middle.

[0023] Reference numerals: 1. Metal skeleton; 2. PEEK coating layer; 21. PEEK outer coating layer; 22. PEEK inner coating layer; 3. Through hole; 4. Composite sealing gasket; 41. First sealing area; 42. First flow channel corner hole area; 43. Second sealing area; 44. Gasket body; 45. Second flow channel corner hole area; and 46. Connecting rib. Detailed Implementation

[0024] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. It should be noted that in the description of this utility model, the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0025] The composite sealing gasket of this invention can be applied to equipment operating under conditions such as high pressure, high temperature, and corrosiveness. This embodiment is described using a composite sealing gasket for a plate heat exchanger as an example.

[0026] like Figure 1 As shown, a composite sealing gasket for highly corrosive conditions is disclosed. The composite sealing gasket 4 includes a gasket body 44 consisting of two primary sealing areas 41, two primary flow channel corner hole areas 42, and two secondary sealing areas 43. Secondary flow channel corner hole areas 45 are laterally provided between the two primary flow channel corner hole areas 42 in the gasket body 44. The secondary flow channel corner hole areas 45 are connected to the secondary sealing areas 43 via connecting ribs 46. Figure 2 and Figure 3 As shown, the composite gasket 4 includes a metal skeleton 1 and a PEEK coating layer 2. The metal skeleton 1 serves as a reinforcing structure, effectively improving the compressive strength and creep resistance of the composite gasket 4 and providing elasticity. PEEK is a semi-crystalline, high-performance thermoplastic special engineering plastic with excellent high-temperature resistance and corrosion resistance, providing a sealing layer for the composite gasket 4. The metal skeleton 1 has several through holes 3, and the PEEK coating layer 2 is connected to the side of the metal skeleton 1 that is in contact with the medium through several through holes 3 to isolate the metal skeleton 1 from the medium.

[0027] As a further optimization, the PEEK coating layer 2 is divided into an outer PEEK coating layer 21 and an inner PEEK coating layer 22. The outer PEEK coating layer 21 and the inner PEEK coating layer 22 are connected to opposite sides of the metal frame 1 through several through holes 3. The inner PEEK coating layer 22 is in contact with the medium inside the heat exchanger and is used to block medium corrosion and resist high temperature. The outer PEEK coating layer 21 can prevent leakage and acid mist from corroding the outside of the metal frame 1.

[0028] As a further optimization, the PEEK coating layer 2 forms an anchoring structure with the metal skeleton 1 by injecting molten PEEK material into several through holes 3 under high pressure. Specifically, the metal skeleton 1 is placed in the middle of the mold, and molten PEEK material is poured inward through the through holes 3 on the metal skeleton 1, allowing the PEEK material to flow through the through holes 3 to the lateral sides of the metal skeleton 1 to fill the gap between the lateral sides of the metal skeleton 1 and the mold, forming the inner PEEK coating layer 22 and the outer PEEK coating layer 21. Since the coefficient of thermal expansion and mechanical properties of PEEK material are different from those of metal material, if the PEEK material does not form a stable bond with the metal skeleton, the heat exchanger is prone to interfacial stress concentration due to thermal cycling or pressure changes during long-term operation, which may lead to cracks in the metal skeleton 1 and may further induce cracking of the PEEK coating layers on both sides. Therefore, in this embodiment, the outer PEEK coating layer 21 and the inner PEEK coating layer 22 are integrated with the metal skeleton 1 to form an integrated composite structure, thereby increasing the overall compressive strength and stability.

[0029] like Figure 2 and Figure 4 As the pressure on the plates varies (lower pressure in the middle and higher pressure at the corner holes at both ends), this embodiment designs the through holes 3 on the metal skeleton 1 at the two primary sealing areas 41 to be large and dense to reduce the rigidity of the metal skeleton 3. Conversely, the through holes 3 on the metal skeleton 1 at the two primary flow channel corner hole areas 42 and the two secondary flow channel corner hole areas 45 are designed to be small and sparse to increase the rigidity of the metal skeleton 3. By adjusting the density and size of the through holes 3 in different areas of the metal skeleton 1, the composite sealing gasket 4 can achieve a balanced pressure distribution, preventing the risk of leakage due to uneven stress causing localized compression and gaps.

[0030] As a further optimization, the through hole 3 supports circular, square and various irregularly shaped holes, and is not limited to a specific form, mainly serving the function of casting connection.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model, and are not intended to limit them. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the present utility model.

Claims

1. A composite sealing gasket for use in highly corrosive environments, characterized in that, It includes a metal skeleton (1) and a PEEK coating layer (2). The metal skeleton (1) is provided with several through holes (3). The PEEK coating layer (2) is connected to the side of the metal skeleton (1) that is in contact with the medium through several through holes (3).

2. The composite sealing gasket for highly corrosive conditions according to claim 1, characterized in that, The PEEK coating layer (2) is divided into an outer PEEK coating layer (21) and an inner PEEK coating layer (22), which are connected to the opposite sides of the metal skeleton (1) through several through holes (3).

3. The composite sealing gasket for highly corrosive conditions according to claim 1, characterized in that, The PEEK coating layer (2) forms an anchoring structure with the metal skeleton (1) by injecting molten PEEK material into several through holes (3) under high pressure.

4. A composite sealing gasket for highly corrosive conditions according to any one of claims 1-3, characterized in that, The composite sealing gasket (4) is a composite sealing gasket for plate heat exchangers. The composite sealing gasket (4) includes a gasket body (44) consisting of two primary sealing areas (41), two primary flow channel corner hole areas (42), and two secondary sealing areas (43). The two primary flow channel corner hole areas (42) in the gasket body (44) are provided with secondary flow channel corner hole areas (45) laterally. The secondary flow channel corner hole areas (45) are connected to the secondary sealing areas (43) through connecting ribs (46). The through holes (3) on the metal skeleton (1) at the two primary sealing areas (41) are large and dense, while the through holes (3) on the metal skeleton (1) at the two primary flow channel corner hole areas (42) and the two secondary flow channel corner hole areas (45) are small and sparse.

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