Flange sealing assembly
By utilizing the reverse thread design and the difference in thermal expansion coefficients of the flange sealing assembly, the problems of difficult disassembly and poor reliability in high-temperature environments are solved, enabling rapid disassembly and efficient sealing under high-temperature conditions and reducing maintenance costs.
Patent Information
- Application Number
- CN202520477151.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2035-03-18
AI Technical Summary
Existing high-temperature flange sealing technologies suffer from problems such as difficulty in disassembly and assembly, poor reliability, or high cost. In particular, high-temperature alloy bolt sealing solutions have failed to effectively address the stress relaxation problem of bolts under high-temperature conditions, resulting in a gradual decrease in sealing capacity over time.
The flange sealing assembly with reverse thread design achieves sealing by utilizing the difference in thermal expansion between the first and second flanges, which is greater than that of the sleeve. Combined with the high-temperature strength and stress relaxation resistance of ceramic materials, and with the addition of sealing gaskets and anti-seize agents, the sealing reliability is improved.
It enables rapid assembly and disassembly of flanges under high-temperature conditions, facilitating maintenance, improving the reliability and durability of the seal, and reducing maintenance costs.
Smart Images
Figure CN223938943U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of flange sealing technology, and in particular to a flange sealing assembly. Background Technology
[0002] In engineering practice, some equipment, such as burners and heat exchangers, faces the challenge of ultra-high temperature environments, some exceeding 700°C. Flanges play a crucial role in these high-temperature devices. The primary function of flanges is to provide a reliable interface, enabling tight connections and seals between different components. In burners and heat exchangers, flanges also play a vital role in preventing leakage of gaseous or liquid media at the connection points.
[0003] However, in ultra-high temperature environments, to ensure overall equipment efficiency, some equipment lacks flange cooling measures, which places stringent requirements on high-temperature gas sealing technology. Currently, common solutions for high-temperature flange sealing mainly include welding and high-temperature alloy bolt sealing. While directly welding the flanges at both ends offers superior sealing performance and high reliability, it prevents disassembly, undoubtedly increasing the manufacturing and maintenance costs of components. Although high-temperature alloy bolt sealing maintains ease of component assembly and disassembly, it fails to effectively address the stress relaxation problem of bolts in high-temperature environments, leading to a gradual decrease in sealing capacity over time. Especially in the application of large flanges, the increased number of high-temperature alloy bolts, nuts, and gaskets further increases costs and makes structural disassembly and assembly more difficult. Utility Model Content
[0004] This application discloses a flange sealing assembly to solve the problems of existing high-temperature flange seals, such as difficulty in disassembly and assembly, poor reliability, or high cost.
[0005] To achieve the above objectives, this application provides the following technical solution:
[0006] In a first aspect, this application provides a flange sealing assembly, which includes a first flange, a second flange, a first sleeve, and a first sealing gasket. The first flange is provided with a first external thread, and the second flange is provided with a second external thread. Along the axial direction of the first sleeve, the first sleeve has a first internal thread and a second internal thread. The first internal thread is used to screw into the first external thread, and the second internal thread is used to screw into the second external thread. The first internal thread and the second internal thread are reverse threads. The first sleeve is sleeved on the outer circumferential surface of the first flange and the second flange, and the first sealing gasket is sandwiched between the first flange and the second flange. When the first sleeve is rotated, the first flange and the second flange move closer to each other or further away from each other. The coefficients of thermal expansion of both the first flange and the second flange are greater than the coefficient of thermal expansion of the first sleeve.
[0007] Because the first internal thread is screwed into the first external thread, and the second internal thread is screwed into the second external thread, and the first internal thread and the second internal thread are reverse threads, when the first sleeve is rotated in a preset direction, the first flange and the second flange can be brought closer together, so that the first flange and the second flange are in a pre-tightened state, and a preliminary seal is achieved by compressing the first sealing gasket. When the temperature of the working environment reaches the preset temperature T, because the thermal expansion coefficients of the first flange and the second flange are both greater than the thermal expansion coefficient of the first sleeve, the expansion degree of the first flange and the second flange is greater than the expansion degree of the first sleeve. The first flange and the second flange will further compress the first sealing gasket, thereby achieving a further seal between the first flange and the second flange. The flange sealing assembly in this application can achieve quick disassembly and assembly between the first flange and the second flange through the reverse threads, which is convenient for maintenance. At the same time, the thermal expansion coefficients of the first flange and the second flange are both greater than the thermal expansion coefficient of the first sleeve, which can achieve thermal expansion matching at high temperatures and improve the reliability of the seal under high temperature conditions.
[0008] Furthermore, the coefficient of thermal expansion of the first sleeve is α1, and the coefficient of thermal expansion of the first flange is α. 21 The coefficient of thermal expansion of the second flange is α. 22 Along the axial direction of the first sleeve, the axial clearance between the first external thread and the first sealing gasket is L1, the axial clearance between the second external thread and the first sealing gasket is L2, the thickness of the first sealing gasket is D, the initial compression of the first sealing gasket is a0, and the target compression of the first sealing gasket at a preset temperature T is a. Then a and a0 satisfy the following relationship:
[0009] a-a0≤L1×α 21 ×T+L2×α 22 ×T-(L1+L2+D-a0)×α1×T;
[0010] The initial compression amount is the compression amount of the first sealing gasket when the first flange and the second flange are in a pre-tightened state under normal temperature conditions.
[0011] Furthermore, both the first flange and the second flange are made of metal or alloy, while the first sleeve is made of ceramic.
[0012] Furthermore, the first sealing gasket is selected from vermiculite gaskets, metal gaskets, ceramic gaskets, or graphite spiral wound gaskets.
[0013] Furthermore, an anti-seize agent is filled between the first internal thread and the first external thread, and / or, an anti-seize agent is filled between the second internal thread and the second external thread.
[0014] Furthermore, along the axial direction of the first sleeve, the length of the first external thread is greater than the length of the second external thread, the length of the first external thread is the same as the length of the first internal thread, and the length of the second external thread is the same as the length of the second internal thread.
[0015] Furthermore, the flange sealing assembly also includes a second sleeve and a second sealing gasket. The second sleeve is located at the end of the first sleeve near the second internal thread, and the second sealing gasket is sandwiched between the first sleeve and the second sleeve. The second flange is provided with a third external thread that is spaced apart from the second external thread and has the same helical direction, and the second sleeve is provided with a third internal thread that mates with the third external thread.
[0016] Furthermore, the second sleeve is made of metal or alloy.
[0017] Furthermore, anti-jamming agent is filled between the third internal thread and the third external thread.
[0018] Furthermore, along the axial direction of the first sleeve, the length of the third external thread is greater than the length of the second external thread; and / or, the strength of the second external thread is greater than the strength of the first external thread. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the structure of a flange sealing assembly according to an embodiment of this application;
[0020] Figure 2 This is a schematic diagram of a structure in which a first sealing gasket is sandwiched between a first flange and a second flange according to an embodiment of this application;
[0021] Figure 3 This is a schematic diagram of the structure of a flange sealing assembly according to another embodiment of this application;
[0022] Figure 4 This is a schematic diagram of a structure in which a first sealing gasket is sandwiched between a first flange and a second flange, according to another embodiment of this application.
[0023] Figure 5 This is a schematic diagram of the structure of the first sleeve being fitted onto the second flange according to another embodiment of this application;
[0024] Figure 6 This is a schematic diagram of the structure of a flange sealing assembly according to another embodiment of this application;
[0025] Figure 7 This is a schematic diagram of a structure in which a first sealing gasket is sandwiched between a first flange and a second flange according to another embodiment of this application;
[0026] Figure 8 This is a schematic diagram of the structure of the second sleeve sleeved on the second flange according to another embodiment of this application;
[0027] Figure 9 This is a schematic diagram of a structure in another embodiment of the present application, in which both the first sleeve and the second sleeve are fitted onto the second flange.
[0028] Reference numerals: 100-First flange; 110-First external thread; 200-Second flange; 210-Second external thread; 220-Third external thread; 300-First sleeve; 310-First internal thread; 320-Second internal thread; 400-First sealing gasket; 500-Second sleeve; 510-Third internal thread; 600-Second sealing gasket. Detailed Implementation
[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0030] Figure 1 This is a schematic diagram of the structure of a flange sealing assembly according to an embodiment of this application. Figure 2 This is a schematic diagram of the structure of a first sealing gasket sandwiched between a first flange and a second flange according to an embodiment of this application. Please refer to... Figure 1 and Figure 2 This application provides a flange sealing assembly, which includes a first flange 100, a second flange 200, a first sleeve 300, and a first sealing gasket 400. The first flange 100 has a first external thread 110, and the second flange 200 has a second external thread 210. Along the axial direction D1 of the first sleeve 300, the first sleeve 300 has a first internal thread 310 and a second internal thread 320. The first internal thread 310 is used to screw into the first external thread 110, and the second internal thread 320 is used to screw into the second external thread 210. The first internal thread 310 and the second internal thread 320 are reverse threads. The first sleeve 300 is sleeved on the outer circumferential surface of the first flange 100 and the second flange 200, and the first sealing gasket 400 is sandwiched between the first flange 100 and the second flange 200. When the first sleeve 300 is rotated, the first flange 100 and the second flange 200 can move closer to or further away from each other. When the first sleeve 300 is rotated in a preset direction, the first flange 100 and the second flange 200 can approach each other to compress the first sealing gasket 400, thereby achieving pre-tightening and initial sealing of the first flange 100 and the second flange 200.
[0031] Furthermore, the coefficients of thermal expansion of the first flange 100 and the second flange 200 are both greater than those of the first sleeve 300. When the flange sealing assembly in this application operates under high temperature conditions, the expansion of the first flange 100 and the second flange 200 is greater than that of the first sleeve 300. The first flange 100 and the second flange 200 will further compress the first sealing gasket 400, thereby achieving further sealing of the first flange 100 and the second flange 200.
[0032] The coefficient of thermal expansion of the first sleeve 300 is α1, and the coefficient of thermal expansion of the first flange 100 is α. 21 The coefficient of thermal expansion of the second flange 200 is α. 22 Along the axial direction D1 of the first sleeve 300, the axial clearance between the first external thread 110 and the first sealing gasket 400 is L1, the axial clearance between the second external thread 210 and the first sealing gasket 400 is L2, the thickness of the first sealing gasket 400 is D, the initial compression of the first sealing gasket 400 is a0, and the target compression of the first sealing gasket 400 at a preset temperature T is a. Then a and a0 satisfy the following relationship:
[0033] a-a0≤L1×α 21 ×T+L2×α 22 ×T-(L1+L2+D-a0)×α1×T;
[0034] The initial compression amount is the compression amount of the first sealing gasket 400 when the first flange 100 and the second flange 200 are in a pre-tightened state under normal temperature conditions.
[0035] In some optional embodiments, when the coefficients of thermal expansion of both the first flange 100 and the second flange 200 are α2, the above formula can be simplified to:
[0036] a-a0≤(L1+L2)×α2×T-(L1+L2+D-a0)×α1×T.
[0037] It is understandable that when the first flange 100 and the second flange 200 are in the pre-tightened state, the initial compression of the first sealing gasket 400 is a0, and the target maximum compression of the first sealing gasket 400 at the preset temperature T is a. According to the above formula, a first sealing gasket 400 of suitable material can be selected to meet the sealing requirements of the first flange 100 and the second flange 200.
[0038] In some optional embodiments, both the first flange 100 and the second flange 200 are made of metal or alloy. For example, the first flange 100 may be made of aluminum, copper, carbon steel, stainless steel, or a copper alloy. Similarly, the second flange 200 may be made of aluminum, copper, carbon steel, stainless steel, or a copper alloy.
[0039] The first flange 100 and the second flange 200 may be made of the same or different materials.
[0040] In some optional embodiments, the first sleeve 300 is made of ceramic or other materials that meet certain conditions. When the first sleeve 300 is a ceramic sleeve, because the coefficient of thermal expansion of metal is higher than that of ceramic, under high-temperature conditions, the expansion of the first flange 100 and the second flange 200 is greater than that of the ceramic structure, which will further compress the first sealing gasket 400, thereby achieving a seal between the first flange 100 and the second flange 200 under high-temperature conditions. In addition, the stress relaxation resistance and high-temperature strength of ceramic are much higher than those of metal, thereby effectively avoiding seal failure caused by material thermal decay, and thus improving the sealing reliability of the flange sealing assembly.
[0041] Stress relaxation refers to the decrease in stress over time in a material that maintains constant deformation.
[0042] It is understandable that when the coefficients of thermal expansion of the first flange 100 and the second flange 200 differ significantly from the coefficient of thermal expansion of the first sleeve 300, reasonable dimensional design is required to achieve thermal expansion matching at high temperatures, thereby ensuring the sealing effect.
[0043] In some optional embodiments, the first sealing gasket 400 is selected from vermiculite gaskets, metal gaskets, ceramic gaskets, or graphite spiral wound gaskets, as long as it can ensure a sealing effect at high temperatures. Among them, vermiculite gaskets are inorganic non-metallic sealing gaskets with low rigidity, which can be used for sealing in both normal and high temperature conditions, and require a certain amount of compression to achieve the sealing function.
[0044] In some alternative embodiments, an anti-seize agent is filled between the first internal thread 310 and the first external thread 110 to fill the gap at the threads of the two threads, thereby improving the sealing effect.
[0045] In some alternative embodiments, an anti-seize agent is filled between the second internal thread 320 and the second external thread 210 to fill the gap at the threads of the two threads, thereby improving the sealing effect.
[0046] Anti-seize agent refers to a high-temperature anti-seize lubricant made by thickening high-temperature resistant synthetic oil with inorganic thickener, adding ultrafine pure copper powder and additives such as rust inhibitors and corrosion inhibitors.
[0047] The flange sealing assembly in this application is applicable to flanges of various structures, and different sealing forms are designed for the ease of movement of the first flange 100 and the second flange 200 and the sealing requirements. The following will be described in detail with reference to the accompanying drawings.
[0048] like Figure 1 and Figure 2 The flange sealing assembly shown is suitable for movable flange structures. By rotating the first sleeve 300, the first flange 100 and the second flange 200 can move relative to each other simultaneously, so as to move closer to or further away from each other.
[0049] Along the axial direction D1 of the first sleeve 300, the length of the first external thread 110 is equal to or close to the length of the second external thread 210.
[0050] Figure 3 This is a schematic diagram of the structure of a flange sealing assembly according to another embodiment of this application. Figure 4 This is a schematic diagram of the structure of a first sealing gasket sandwiched between a first flange and a second flange according to another embodiment of this application. (Refer to...) Figure 3 and Figure 4 Along the axial direction of the first sleeve 300, the length of the first external thread 110 is greater than the length of the second external thread 210, the length of the first external thread 110 is the same as the length of the first internal thread 310, and the length of the second external thread 210 is the same as the length of the second internal thread 320.
[0051] The flange sealing assembly with the above structure is suitable for flanges in locations where movement is difficult or inconvenient. Its structure has been described above, and the assembly process and working principle of the flange sealing assembly with the above structure will be explained below.
[0052] The assembly steps for the flange sealing assembly with the above structure are as follows:
[0053] Figure 5 This is a schematic diagram of the structure of the first sleeve sleeved on the second flange according to another embodiment of this application, as shown below. Figure 5 As shown, the first sleeve 300 is fitted onto the outer circumferential surface of the second flange 200;
[0054] Align the second flange 200 with the first flange 100, and clamp the first sealing gasket 400 between the first flange 100 and the second flange 200.
[0055] Rotate the first sleeve 300 in the direction of the second flange 200 pointing to the first flange 100. At this time, because the tightening direction of the first internal thread 310 and the second internal thread 320 is consistent with the tightening direction of the thread on the left, but because the number of second external threads 210 is small, only the first internal thread 310 is tightened, thereby achieving overall structural sealing.
[0056] In some optional embodiments, the contact area between the second external thread 210 and the second internal thread 320 is small. The width of the thread root of the second external thread 210 and the second internal thread 320 can be adjusted appropriately according to actual needs to improve thread strength.
[0057] It is understandable that in the flange sealing assembly of the above structure, a first sealing gasket 400 of appropriate material can be selected according to actual needs, and a first internal thread 310 and a second internal thread 320 of appropriate length can be set to meet the sealing requirements under high temperature conditions.
[0058] In the flange sealing assembly with the above structure, the contact area between the second external thread 210 and the second internal thread 320 is small, and conventional measures cannot directly seal this area.
[0059] In view of this, the present application also provides a flange sealing assembly according to another embodiment. Figure 6 This is a schematic diagram of the structure of a flange sealing assembly according to another embodiment of this application. Figure 7 This is a schematic diagram of the structure of a first sealing gasket sandwiched between a first flange and a second flange according to another embodiment of this application. (Refer to...) Figure 6 and Figure 7 The flange sealing assembly also includes a second sleeve 500 and a second sealing gasket 600. The second sleeve 500 is located at the end of the first sleeve 300 near the second internal thread 320, and the second sealing gasket 600 is sandwiched between the first sleeve 300 and the second sleeve 500. The second flange 200 is provided with a third external thread 220 that is spaced apart from the second external thread 210 and has the same helical direction. The second sleeve 500 is provided with a third internal thread 510 that mates with the third external thread 220.
[0060] The assembly steps for the flange sealing assembly with the above structure are as follows:
[0061] Figure 8 This is a schematic diagram of the structure of the second sleeve sleeved on the second flange according to another embodiment of this application, as shown below. Figure 8 As shown, the second sleeve 500 is fitted onto the outer circumferential surface of the second flange 200, and the third internal thread 510 and the third external thread 220 are screwed together.
[0062] Figure 9 This is a schematic diagram of a structure in another embodiment of the present application, in which both the first sleeve and the second sleeve are fitted onto the second flange. Figure 6 and Figure 9 As shown, the first sleeve 300 is sleeved on the outer circumferential surface of the second flange 200, and the second sealing gasket 600 is sandwiched between the first sleeve 300 and the second sleeve 500. The first sleeve 300 and the second sleeve 500 drive the second sealing gasket 600 to rotate in the direction of the second external thread 210 pointing to the third external thread 220.
[0063] Align the second flange 200 with the first flange 100, and clamp the first sealing gasket 400 between the first flange 100 and the second flange 200. Rotate the first sleeve 300 in the direction of the second flange 200 pointing to the first flange 100. At this time, since the tightening direction of the first internal thread 310 and the second internal thread 320 is the same, and the number of second internal threads 320 is small, only the first internal thread 310 is tightened, thereby achieving the sealing of the entire structure.
[0064] The second sleeve 500 is rotated toward the first sleeve 300 so that the first sleeve 300 and the second sleeve 500 clamp the second sealing gasket 600, thereby further achieving a seal between the first flange 100 and the second flange 200.
[0065] In some optional embodiments, the second sleeve 500 is made of metal or alloy. When the flange sealing assembly operates under high temperature conditions, the second sleeve 500 expands due to heat, which further compresses the second sealing gasket 600, thereby improving the sealing reliability of the flange sealing assembly under high temperature conditions in this application.
[0066] Reference Figures 7 to 9 Along the axial direction of the first sleeve 300, the length of the third external thread 220 is greater than the length of the second external thread 210, that is, the contact area between the third external thread 220 and the third internal thread 510 is larger, which improves the sealing effect.
[0067] In some alternative embodiments, the strength of the second external thread 210 is greater than the strength of the first external thread 110.
[0068] In some alternative embodiments, an anti-seize agent is filled between the third internal thread 510 and the third external thread 220 to fill the gap at the threads of the two threads, thereby improving the sealing effect.
[0069] In summary, the flange sealing assembly of this application has the following advantages:
[0070] 1) The first internal thread 310 and the second internal thread 320 are reverse threads, which reduces the number of parts, facilitates disassembly and assembly, and improves maintenance efficiency;
[0071] 2) The first flange 100, the second flange 200 and the first sleeve 300 have different coefficients of thermal expansion. Through reasonable size design, thermal expansion matching at high temperature can be achieved to ensure the sealing effect under high temperature conditions.
[0072] 3) The internal seal uses a gasket, and the external seal uses an anti-seize compound between the threads, providing a double seal to improve the reliability of the seal.
[0073] 4) Ceramic has a much higher stress relaxation resistance and high temperature strength than metal, thus avoiding sealing failure caused by material thermal decay.
[0074] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of this application. Therefore, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.
Claims
1. A flange sealing assembly, characterized in that, It includes a first flange, a second flange, a first sleeve, and a first sealing gasket, wherein the first flange is provided with a first external thread, and the second flange is provided with a second external thread; Along the axial direction of the first sleeve, the first sleeve has a first internal thread and a second internal thread, the first internal thread is used to screw into the first external thread, the second internal thread is used to screw into the second external thread, and the first internal thread and the second internal thread are reverse threads; The first sleeve is fitted onto the outer circumferential surfaces of the first flange and the second flange, and the first sealing gasket is sandwiched between the first flange and the second flange. When the first sleeve is rotated, the first flange and the second flange move closer to or further away from each other. The coefficients of thermal expansion of both the first flange and the second flange are greater than the coefficient of thermal expansion of the first sleeve.
2. The flange sealing assembly according to claim 1, characterized in that, The coefficient of thermal expansion of the first sleeve is α1, and the coefficient of thermal expansion of the first flange is α. 21 The coefficient of thermal expansion of the second flange is α. 22 Along the axial direction of the first sleeve, the axial clearance between the first external thread and the first sealing gasket is L1, the axial clearance between the second external thread and the first sealing gasket is L2, the thickness of the first sealing gasket is D, the initial compression of the first sealing gasket is a0, and the target compression of the first sealing gasket at a preset temperature T is a. Then a and a0 satisfy the following relationship: a-a0≤L1×α 21 ×T+L2×α 22 ×T-(L1+L2+D-a0)×α1×T; Wherein, the initial compression amount is the compression amount of the first sealing gasket when the first flange and the second flange are in a pre-tightened state under normal temperature conditions.
3. The flange sealing assembly according to claim 2, characterized in that, The first flange and the second flange are both made of metal or alloy, and the first sleeve is made of ceramic.
4. The flange sealing assembly according to claim 2, characterized in that, The first sealing gasket is selected from vermiculite gaskets, metal gaskets, ceramic gaskets, or graphite spiral wound gaskets.
5. The flange sealing assembly according to claim 2, characterized in that, An anti-seize agent is filled between the first internal thread and the first external thread, and / or, an anti-seize agent is filled between the second internal thread and the second external thread.
6. The flange sealing assembly according to any one of claims 1-5, characterized in that, Along the axial direction of the first sleeve, the length of the first external thread is greater than the length of the second external thread, the length of the first external thread is the same as the length of the first internal thread, and the length of the second external thread is the same as the length of the second internal thread.
7. The flange sealing assembly according to claim 6, characterized in that, The flange sealing assembly further includes a second sleeve and a second sealing gasket, the second sleeve being located at the end of the first sleeve near the second internal thread, and the second sealing gasket being sandwiched between the first sleeve and the second sleeve; The second flange is provided with a third external thread that is spaced apart from the second external thread and has the same helical direction, and the second sleeve is provided with a third internal thread that mates with the third external thread.
8. The flange sealing assembly according to claim 7, characterized in that, The second sleeve is made of metal or alloy.
9. The flange sealing assembly according to claim 7, characterized in that, Anti-jamming agent is filled between the third internal thread and the third external thread.
10. The flange sealing assembly according to claim 7, characterized in that, Along the axial direction of the first sleeve, the length of the third external thread is greater than the length of the second external thread; and / or, The strength of the second external thread is greater than the strength of the first external thread.