An observation window structure and production equipment

Abstract

The utility model discloses an observation window structure and production equipment, this observation window structure includes welding flange, transparent observation window, sealing assembly and pressboard. First, second sealing piece forms double bottom support seal at welding flange end, cooperates the third sealing piece of cladding observation window periphery, has built multilayer sealing protection structure, even when solvent corrosion leads to single pass sealing performance decline, the rest sealing layer still can maintain integral sealing effect, has improved sealing reliability and service life significantly. At the same time, the clear observation window is supported on the flexible sealing piece and avoids the stress concentration produced by rigid contact, effectively prevents the risk that the observation window breaks down because of excessive local stress under the negative pressure or pressure fluctuation working condition. Thus realized long -term stable operation in the strong corrosive solvent environment, greatly reduced the security risk and maintenance cost because of the sealing failure, improved the overall operation efficiency and safety of chemical equipment.

Description

Technical Field

[0001] This utility model relates to the field of industrial equipment, and in particular to an observation window structure and production equipment. Background Technology

[0002] In industrial production processes such as chemical and pharmaceutical manufacturing, observation windows are typically installed in enclosed tanks to facilitate observation and monitoring of the tank's internal working conditions. The design of these observation windows presents significant challenges, particularly in production environments containing highly corrosive solvents such as dichloromethane (DCM).

[0003] Existing observation window structures typically use ordinary tempered glass as the transparent material and are sealed with rubber or plastic sealing rings. This structure has several technical drawbacks in environments with highly polar solvents such as dichloromethane: First, dichloromethane has strong solubility or corrosiveness to most polymers (such as ordinary rubber and PVC) and some metals (such as aluminum), easily causing ordinary glass, acrylic, and other transparent materials to fog and crack, and the sealing ring to swell and age, ultimately leading to leakage; Second, dichloromethane is volatile, and its vapor condenses on the surface of the low-temperature observation window to form a liquid film, scattering light. At the same time, impurities or reaction byproducts in the tank easily adhere to the inner surface of the window, making it difficult to clean and affecting the observation effect; Third, under negative pressure or pressure fluctuations in the tank (such as during material extraction), existing observation windows are prone to cracking due to stress concentration, posing a safety hazard. Utility Model Content

[0004] In order to overcome the shortcomings of the prior art, this utility model provides an observation window structure with multiple sealing structures, high corrosion resistance and good observation performance, as well as production equipment using the observation window structure.

[0005] The technical solution adopted by this utility model to solve its technical problem is: An observation window structure includes: a welding flange, a transparent observation window, a sealing assembly, and a pressure plate; the sealing assembly includes a first sealing element, a second sealing element, and a third sealing element; the outer end face of the welding flange is provided with a first annular sealing groove and a second annular sealing groove arranged concentrically, the first sealing element being embedded in the first annular sealing groove, and the second sealing element being embedded in the second annular sealing groove; the transparent observation window is supported on the first sealing element and the second sealing element; the third sealing element covers the outer peripheral edge of the transparent observation window, including an axial sealing surface covering the upper surface edge of the transparent observation window and a radial sealing surface conforming to the side surface of the transparent observation window; the pressure plate has a bidirectional pressing structure, including an axial pressing portion covering the axial sealing surface of the third sealing element and a radial pressing portion abutting the radial sealing surface of the third sealing element; a fastening assembly is inserted between the pressure plate and the welding flange for fixing the pressure plate to the welding flange and applying a preload force to the sealing assembly.

[0006] Furthermore, the first annular sealing groove is a rectangular cross-section groove, with its groove wall and groove bottom forming a right angle structure; the first sealing element is a rectangular cross-section sealing strip, with its width clearance matching the groove width of the first annular sealing groove and its height interference matching the groove depth.

[0007] Furthermore, the second annular sealing groove has a rectangular cross-section; the second sealing element is an annular sealing body with a circular cross-section; the height of the circular cross-section annular sealing body is greater than the depth of the rectangular cross-section groove, and the width of the circular cross-section annular sealing body is less than the width of the rectangular cross-section groove.

[0008] Furthermore, the fastening assembly includes a circumferentially distributed group of bolts, the welding flange is provided with corresponding threaded holes, and the pressure plate is provided with through holes.

[0009] Furthermore, the third sealing element is an L-shaped cross-section member, with its L-shaped horizontal side forming the axial sealing surface and its L-shaped vertical side forming the radial sealing surface.

[0010] Furthermore, the radial pressing portion and the axial pressing portion of the pressure plate are integrated in an L-shape and match the L-shaped cross-section of the third sealing element.

[0011] Furthermore, the edge of the axial pressing part is provided with a flared structure, which gradually expands in the direction away from the pressing surface to form an installation guide opening.

[0012] Furthermore, the first and third seals are made of polytetrafluoroethylene; the second seal is made of fluororubber.

[0013] Furthermore, the transparent observation window is made of borosilicate glass.

[0014] A production device includes a sealed tank and an observation window structure; the observation window structure is as described above; the observation window structure is installed on the sealed tank to form a visual monitoring window for observing the internal state of the sealed tank.

[0015] The beneficial effects of this utility model are: This invention discloses an observation window structure that employs first and second sealing elements to form a double bottom support seal at the welded flange end. Combined with a third sealing element covering the perimeter of the observation window, this constructs a multi-layered sealing and protection structure. Even when solvent corrosion causes a decline in the performance of a single seal, the remaining sealing layers can still maintain the overall sealing effect, significantly improving sealing reliability and service life. Simultaneously, the transparent observation window is supported on a flexible sealing element, avoiding stress concentration caused by rigid contact. The axial and radial bidirectional pressing structure of the pressure plate ensures uniform pressure distribution throughout the sealing structure, effectively preventing the risk of the observation window rupturing due to excessive local stress under negative pressure or pressure fluctuation conditions. This achieves long-term stable operation in highly corrosive solvent environments, significantly reducing safety hazards and maintenance costs caused by seal failure, and improving the overall operating efficiency and safety of chemical equipment. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Figure 1 This is a three-dimensional structural schematic diagram of the present invention; Figure 2 This is a cross-sectional structural diagram of the present invention; Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0018] 1. Welded flange; 11. First annular sealing groove; 12. Second annular sealing groove; 13. Threaded hole; 2. Transparent viewing window; 3. Sealing assembly; 31. First seal; 32. Second seal; 33. Third seal; 4. Pressure plate; 41. Axial pressing part; 42. Radial pressing part; 43. Flared structure; 44. Through hole; 5. Fastening components. Detailed Implementation

[0019] The following will clearly and completely describe the concept, specific structure, and technical effects of this utility model in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are all within the scope of protection of this utility model. Furthermore, all connections / linkages involved in the patent do not simply refer to direct contact between components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The various technical features in this utility model can be combined interactively without contradicting each other.

[0020] This invention relates to an observation window structure suitable for sealed tanks containing highly corrosive solvents such as dichloromethane, specifically an observation window structure with multiple seals, high corrosion resistance, and good light transmittance. This invention solves the technical problems of traditional observation windows in highly corrosive environments, such as insufficient material corrosion resistance, poor sealing, insufficient light transmittance and anti-fouling properties, and insufficient structural strength. It is particularly suitable for sealed tanks containing highly polar solvents such as dichloromethane (e.g., reaction vessels, storage tanks), and can operate stably under negative pressure, pressure fluctuations, or deep working environments.

[0021] like Figure 1-3 As shown, the observation window structure of this utility model mainly includes a welding flange 1, a transparent observation window 2, a sealing assembly 3, and a pressure plate 4. The welding flange 1 is welded to the sealed tank, the transparent observation window 2 is sealed to the welding flange 1 through the sealing assembly 3, and the pressure plate 4 is fixed to the welding flange 1 through the fastening assembly 5, applying a pre-tightening force to the sealing assembly 3 to ensure the sealing and stability of the entire observation window structure.

[0022] The outer end face of the welded flange 1 is provided with a first annular sealing groove 11 and a second annular sealing groove 12 arranged concentrically, which cooperate with the first sealing element 31 and the second sealing element 32 respectively to form the first and second sealing barriers, effectively preventing the leakage of dichloromethane. The welded flange 1 is preferably made of 316L stainless steel, which has excellent corrosion resistance and can work stably for a long time in a dichloromethane environment.

[0023] The outer edge of the welding flange 1 is also provided with multiple circumferentially distributed threaded holes 13 for installing fastening components 5. This ensures uniform pressure distribution and avoids the risk of the transparent observation window 2 cracking due to uneven stress during installation.

[0024] The transparent observation window 2 is made of high borosilicate glass. High borosilicate glass is virtually inert to dichloromethane, acids, and alkalis, and will not swell or fog with long-term use. It has a high surface hardness (Mohs 6.5), is not easily scratched, and ensures clear observation results over a long period of time.

[0025] Reference Figure 3 The sealing assembly 3 includes a first seal 31, a second seal 32 and a third seal 33, forming a triple sealing guarantee.

[0026] The first sealing element 31 is embedded in the first annular sealing groove 11. It is a rectangular cross-section sealing ring made of polytetrafluoroethylene (PTFE). PTFE has extremely high resistance to dichloromethane and will not swell, soften, or dissolve. The width of the first sealing element 31 is clearance-fitted with the groove width of the first annular sealing groove 11, and its height is interference-fitted with the groove depth, ensuring a good sealing effect. The first sealing element 31 mainly performs the basic static sealing function, preventing dichloromethane leakage along the contact surface between the welded flange 1 and the transparent observation window 2.

[0027] The second sealing element 32 is embedded within the second annular sealing groove 12 and is an annular sealing body with a circular cross-section, made of fluororubber. The second annular sealing groove 12 has a rectangular cross-section, while the height of the circular-section second sealing element 32 is greater than the depth of the rectangular groove, and the width is less than the width of the rectangular groove. This allows the second sealing element 32 to undergo elastic deformation under pressure, filling the tiny gaps between the sealing surfaces and forming a dynamic seal. Fluororubber has excellent resistance to dichloromethane while maintaining good elasticity, enabling it to adapt to minute displacements caused by pressure fluctuations.

[0028] The third seal 33 covers the outer periphery of the transparent observation window 2, forming an L-shaped cross-section component. Its L-shaped horizontal side forms an axial sealing surface covering the upper surface edge of the transparent observation window 2, and its L-shaped vertical side forms a radial sealing surface conforming to the side of the transparent observation window 2. The third seal 33 is also made of PTFE, ensuring complete corrosion resistance to dichloromethane. On the one hand, the third seal provides bidirectional sealing protection for the transparent observation window 2, preventing liquid leakage from any direction; on the other hand, it acts as a buffer layer to prevent direct contact between the pressure plate 4 and the transparent observation window 2, avoiding stress concentration caused by hard contact between metal and glass, and significantly reducing the risk of the transparent observation window 2 cracking due to uneven local pressure during installation and use. Especially when temperature fluctuations cause stress due to differences in the thermal expansion coefficients of the materials, the third seal 33 can buffer and disperse stress, further improving the safety and reliability of the observation window structure.

[0029] Reference Figure 3 The pressure plate 4 has a bidirectional pressing structure that matches the third seal 33, including an axial pressing portion 41 that covers the axial sealing surface of the third seal 33 and a radial pressing portion 42 that abuts against the radial sealing surface of the third seal 33. The radial pressing portion 42 and the axial pressing portion 41 of the pressure plate 4 are integrated in an L-shape, which perfectly matches the L-shaped cross-section of the third seal 33.

[0030] Reference Figure 3 In a preferred embodiment, the edge of the axial pressing portion 41 is provided with a flared structure 43. The flared structure 43 gradually widens in a direction away from the pressing surface to form an installation guide opening, which facilitates the installation of the third sealing element 33, reduces the installation difficulty, and improves the installation efficiency.

[0031] The pressure plate 4 is preferably made of 316L stainless steel, the same material as the welding flange 1, to ensure consistent corrosion resistance throughout the system. The pressure plate 4 is provided with through holes 44 corresponding to the threaded holes 13 on the welding flange 1, for installing the fastening assembly 5.

[0032] The fastening assembly 5 includes a circumferentially distributed group of bolts, which pass through the through hole 44 of the pressure plate 4 and the threaded hole 13 of the welding flange 1. The fastening assembly 5 fixes the pressure plate 4 to the welding flange 1 and applies a preload to the sealing assembly 3 to ensure the sealing and stability of the entire observation window structure.

[0033] In a preferred embodiment, the bolt assembly is made of 316L stainless steel, with 8-12 bolts evenly distributed around the circumference to ensure uniform pressure transmission. The tightening torque of each bolt is controlled at 35-40 N·m, which ensures sufficient sealing preload while avoiding excessive stress concentration on the transparent observation window 2.

[0034] This invention employs a triple-seal design, forming a complete sealing and protection system: the first sealing element 31 and the second sealing element 32 are respectively embedded in the two concentric annular sealing grooves of the welded flange 1, forming two basic sealing barriers; the L-shaped structure of the third sealing element 33 provides bidirectional sealing protection in both the axial and radial directions. This multi-seal design ensures that even if a sealing surface experiences minor aging or damage when exposed to highly corrosive solvents such as dichloromethane, the other sealing components can still maintain an effective seal, greatly improving the overall system's sealing reliability and service life.

[0035] Furthermore, this invention addresses the characteristics of dichloromethane by selecting high borosilicate glass as the transparent observation window 2. This glass is virtually inert to dichloromethane, preventing fogging and cracking, and exhibits high surface hardness and scratch resistance. Polytetrafluoroethylene (PTFE) is used for the first and third sealing elements 31 and 33, ensuring complete resistance to dichloromethane without swelling or deformation. Fluororubber is used for the second sealing element 32, providing both dichloromethane resistance and necessary elasticity. 316L stainless steel is used for the welding flange 1 and pressure plate 4, offering excellent corrosion resistance. This material combination ensures the long-term stable operation of the observation window structure in a dichloromethane environment, effectively solving the problems of easy corrosion of traditional observation window materials and easy aging of sealing elements.

[0036] In addition to the basic embodiments described above, this invention also includes various optimized design schemes to further improve the performance and applicability of the observation window structure. In practical applications, the condensation of dichloromethane vapor is one of the main factors affecting the observation effect. To solve this problem, this invention provides an improved solution: a special anti-fog coating is applied to the surface of the transparent observation window 2. This coating, based on hydrophilic nanomaterial technology, effectively reduces the contact angle between water molecules and the glass surface, causing condensate to form a uniform film instead of droplets, significantly reducing light scattering. This coating is prepared using the sol-gel method, exhibiting good optical transparency while maintaining chemical stability against dichloromethane.

[0037] To further optimize sealing performance, this invention proposes a composite material structure design for the third sealing element 33. This design employs a double-layer composite structure. The inner layer is made of standard PTFE material, directly contacting dichloromethane and providing excellent chemical stability. The outer layer uses modified PTFE material, which, through the addition of trace fillers (such as glass fiber or carbon fiber) and special processing techniques, improves the material's elastic resilience and compressive deformation capacity. While maintaining basic corrosion resistance, it significantly improves the mechanical properties of the sealing element, especially its sealing adaptability under temperature fluctuation conditions.

[0038] To further address the issue of dichloromethane condensate accumulation on the observation window surface, welded flange 1 features an inner surface design with a 5°-10° tilt angle, creating a natural drainage channel. Utilizing gravity, dichloromethane droplets condensed on the observation window surface automatically flow to the bottom of the tank, preventing the formation of a liquid film that obstructs the view. Simultaneously, a miniature collection tank and reflux hole are designed at the bottom of the tilted surface to further promote condensate recovery and circulation.

[0039] Finally, this invention designs a detachable protective cover, which is installed on the outer surface of the pressure plate 4. The protective cover is made of 304 stainless steel, possessing excellent mechanical strength and corrosion resistance. The design of the protective cover considers practicality and convenience, employing a snap-on quick-installation structure that allows for tool-free installation and removal, facilitating daily maintenance and inspection. The protective cover not only protects the transparent observation window 2 from mechanical damage but also extends the service life of the fastening components 5, improving the reliability and durability of the entire system.

[0040] The observation window structure provided by this invention solves the technical problems faced by observation windows in highly corrosive solvent environments such as dichloromethane, including material corrosion resistance and sealing failure, insufficient light transmittance and anti-fouling properties, and structural strength and safety risks. Through a triple-sealing design, reasonable material selection, and structural coordination, this invention addresses these issues. This invention has significant engineering application value, meeting the visual monitoring needs of industries such as chemical and pharmaceutical manufacturing in corrosive environments, and improving the safety and controllability of production processes.

[0041] The above is a detailed description of the preferred embodiments of the present utility model. However, the present utility model is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present utility model. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. An observation window structure, characterized in that, include: Welding flange, transparent observation window, sealing assembly and pressure plate; The sealing assembly includes a first seal, a second seal, and a third seal; The outer end face of the welding flange is provided with a first annular sealing groove and a second annular sealing groove arranged concentrically. The first sealing element is embedded in the first annular sealing groove, and the second sealing element is embedded in the second annular sealing groove. The transparent observation window is supported on the first seal and the second seal; The third sealing element covers the outer peripheral edge of the transparent observation window, including an axial sealing surface covering the upper surface edge of the transparent observation window and a radial sealing surface conforming to the side surface of the transparent observation window; The pressure plate has a bidirectional pressing structure, including an axial pressing part that covers the axial sealing surface of the third seal and a radial pressing part that abuts against the radial sealing surface of the third seal. A fastening assembly, inserted between the pressure plate and the welding flange, is used to fix the pressure plate to the welding flange and apply a preload to the sealing assembly.

2. The observation window structure according to claim 1, characterized in that, The first annular sealing groove is a rectangular cross-section groove, and its groove wall and groove bottom form a right angle structure; The first sealing element is a rectangular cross-section sealing strip, the width of which is clearance-fitted with the width of the first annular sealing groove, and the height of which is interference-fitted with the groove depth.

3. The observation window structure according to claim 1, characterized in that, The second annular sealing groove has a rectangular cross-section; The second seal is an annular seal with a circular cross-section; The height of the circular cross-section annular seal is greater than the depth of the rectangular cross-section, and the width of the circular cross-section annular seal is less than the width of the rectangular cross-section.

4. The observation window structure according to claim 1, characterized in that, The fastening assembly includes a group of bolts evenly distributed around the circumference, the welding flange has corresponding threaded holes, and the pressure plate has through holes.

5. The observation window structure according to claim 1, characterized in that, The third sealing element is an L-shaped cross-section member, with its L-shaped horizontal side forming the axial sealing surface and its L-shaped vertical side forming the radial sealing surface.

6. The observation window structure according to claim 5, characterized in that, The radial pressing portion and the axial pressing portion of the pressure plate are integrated in an L-shape and match the L-shaped cross-section of the third sealing element.

7. The observation window structure according to claim 6, characterized in that, The edge of the axial pressing part is provided with a flared structure, which gradually expands in the direction away from the pressing surface to form an installation guide opening.

8. The observation window structure according to claim 1, characterized in that, The first and third seals are made of polytetrafluoroethylene (PTFE). The second seal is made of fluororubber.

9. The observation window structure according to claim 1, characterized in that, The transparent observation window is made of borosilicate glass.

10. A production equipment, characterized in that: The production equipment includes a sealed tank and an observation window structure; The observation window structure is the observation window structure as described in any one of claims 1 to 9; The observation window structure is installed on the sealed tank to form a visual monitoring window, so as to facilitate the observation of the internal state of the sealed tank.

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