A sealing structure of a high-pressure flange

Abstract

The utility model belongs to the technical field of flange sealing, especially a sealing structure of high pressure flange, in view of the low sealing reliability, unstable fixation, lack of multiple sealing, insufficient assembly accuracy, gap sealing deficiency etc. of prior art, the following scheme is presented, it includes: two flange bodies and sealing structure body, first sealing device is equipped with two, two first sealing devices are all established on sealing structure body, be used for carrying out sealing work to two flange bodies, the utility model not only effectively overcomes the low sealing reliability, unstable fixation, lack of multiple sealing, insufficient assembly accuracy, gap sealing deficiency etc. of prior art, and through the innovative multiple sealing and double fixed structure combination, provide a kind of sealing reliable, stable structure, adapt to severe working conditions, dismounting and maintenance convenient new high pressure flange sealing structure, has very high practical value and market prospect.

Description

Technical Field

[0001] This application relates to the field of flange sealing technology, and in particular to a sealing structure for a high-pressure flange. Background Technology

[0002] In industries such as petroleum, chemical, natural gas, and power, high-pressure flanges are critical components for pipeline connections, and their sealing performance directly affects the safe and stable operation of the entire pipeline system. High-pressure flanges must withstand high pressure and temperature during operation, and the media often possess corrosive, flammable, and explosive properties, thus placing extremely stringent requirements on the sealing structure.

[0003] Currently, most high-pressure flange sealing structures on the market employ single sealing elements or simple combined sealing methods, which have several shortcomings. First, sealing reliability is poor. Under long-term high pressure, high temperature, or corrosive media, sealing elements are prone to aging, deformation, or wear, leading to seal failure and media leakage accidents. This not only causes economic losses but may also endanger personal safety. Second, the sealing structure's fixation effect is poor. When the pipeline vibrates or pressure fluctuates, the sealing element is prone to displacement, further exacerbating the leakage risk. Third, there is a lack of effective multi-seal protection; if the main sealing element malfunctions, it cannot provide timely secondary sealing. Additionally, insufficient assembly precision between the sealing structure and the flange body can easily lead to gaps between the sealing surfaces, affecting the sealing effect. Furthermore, inadequate consideration of the gap sealing between the sealing structure and the fixing device can also lead to potential leakage hazards.

[0004] Chinese utility model patent CN213871578U discloses a high-pressure flange sealing structure, comprising: a flange, a rectangular sleeve fixedly fitted on one side of the flange, a T-shaped device fixedly connected on one side of the rectangular sleeve, a fixedly installed sealing surface inside the T-shaped device, a fixedly fitted fixing rod inside the sealing surface, a fixedly fitted connecting rod inside the fixing rod, and a movablely fitted fixing component at one end of the connecting rod. This high-pressure flange sealing structure achieves excellent sealing performance through the sealing surface. After the sealing surface relaxes, the fixing rod and connecting rod have sufficient rebound to tightly fit the flange, resulting in good sealing reliability. The flange structure is simple, easy to install and remove, and simplifies the product structure, reduces manufacturing costs and production difficulty, lowers the flange height, and better ensures the stability and reliability of the flange.

[0005] Chinese utility model patent CN216618938U discloses a high-pressure flange sealing structure, including a first flange, a second flange, a first threaded pipe, and a second threaded pipe. The first flange and the second flange are arranged opposite each other, with the first flange and the first threaded pipe fixedly sleeved together, and the second flange and the second threaded pipe fixedly sleeved together. An annular protrusion is fixedly provided on the left side of the second flange, and the annular protrusion is fixedly sleeved with the second threaded pipe. An annular slot is provided on the right side of the first flange, allowing the annular protrusion to slide into it. An anti-loosening mechanism is provided in the annular slot. Multiple evenly distributed first fixing holes are provided on the side of the first flange, and multiple second fixing holes are provided on the side of the second flange and the annular protrusion. This utility model enables a more secure connection between the first and second flanges, improves the high-pressure resistance of the connected first and second flanges, prevents the first and second flanges from being affected by high-pressure compression, and facilitates user operation.

[0006] Existing technologies suffer from defects such as low sealing reliability, unstable fixing, lack of multiple seals, insufficient assembly precision, and inadequate gap sealing, which urgently need to be addressed. Utility Model Content

[0007] In order to improve the problems of low sealing reliability, unstable fixing, lack of multiple seals, insufficient assembly accuracy, and lack of gap sealing in the existing technology, this application provides a sealing structure for a high-pressure flange.

[0008] The sealing structure of a high-pressure flange provided in this application adopts the following technical solution: A sealing structure for a high-pressure flange includes: two flange bodies and a sealing structure body; The first sealing device is provided in two parts, both of which are located on the sealing structure body and are used to seal the two flange bodies. The first fixing device is provided in two parts, which are respectively located on the rear side of the two first sealing devices and are used to fix the two first sealing devices. The second fixing device is provided in two parts, which are respectively located in front of the two first sealing devices and are used to fix the two flange bodies. The second sealing device is located on the inner wall of the sealing structure body and is used to perform secondary sealing work on the flange body. There are two third sealing devices, which are respectively installed on the two first sealing devices and are used to seal the gap between the two second fixing devices.

[0009] Preferably, the first sealing device on the front side includes a flexible graphite-filled polytetrafluoroethylene ring. The front side of the sealing structure body has an installation groove, and a sealing gasket is provided inside the installation groove. The flexible graphite-filled polytetrafluoroethylene ring is fixedly connected to the top of the sealing gasket. The flange body is located between the flexible graphite-filled polytetrafluoroethylene ring and the sealing gasket. The flexible graphite-filled polytetrafluoroethylene ring is located on the periphery of the flange body. The two first sealing devices are symmetrically distributed with the transverse central axis of the sealing structure body as the center.

[0010] Preferably, the first fixing device on the front side includes a locking block, the rear side of the sealing gasket is fixedly connected to the locking block, the mounting groove has a locking slot, the locking block and the locking slot are engaged and connected, and the two first fixing devices are symmetrically distributed with the transverse central axis of the sealing structure body as the center.

[0011] Preferably, the second fixing device at the front end includes multiple fixing grooves, and the sealing gasket has multiple mounting holes. The multiple fixing grooves are fixedly connected to the inner wall of the mounting groove. The multiple fixing grooves penetrate the through hole of the flange body and the multiple mounting holes. The interior of the multiple fixing grooves is threaded with fixing bolts. The two second fixing devices are symmetrically distributed with the transverse central axis of the sealing structure body as the center.

[0012] Preferably, the second sealing device includes a metal bellows ring, which is fixedly connected inside the through hole of the sealing structure body. Both sides of the metal bellows ring are fixedly connected with sealing rings, and the two sealing rings are respectively located on the front side of the inner ring of the two flange bodies.

[0013] Preferably, the third sealing device on the front side includes multiple sealing sleeves, which are fixedly connected to multiple mounting holes and slidably connected to multiple fixing grooves. The two third sealing devices are symmetrically distributed with the transverse central axis of the sealing structure body as the center.

[0014] In summary, this application includes at least one of the following beneficial technical effects: 1. Multiple sealing mechanisms ensure extremely high sealing reliability: The system employs a triple sealing design consisting of a first sealing device, a second sealing device, and a third sealing device. The first sealing device provides an initial seal to the outer perimeter of the flange body using a flexible graphite-filled PTFE ring and a sealing gasket. The second sealing device, with its corrugated metal ring and sealing ring, provides a secondary seal to the inner ring of the flange body, forming a double main seal. The sealing sleeve of the third sealing device seals the gap in the second fixing device, blocking leakage channels. This synergistic effect of multiple sealing mechanisms significantly improves sealing reliability and effectively prevents media leakage.

[0015] 2. Double-fixation guarantee for a stable and robust structure: The first fixing device secures the sealing gasket within the mounting groove through the engagement of the locking block and the locking groove, preventing displacement of the first sealing device; the second fixing device uses a fixing groove and fixing bolts to tightly connect and fix the flange body to the sealing structure body. This double-fixation structure ensures the positional stability of each sealing element and flange body under high pressure, vibration, and other operating conditions, avoiding seal failure due to displacement.

[0016] 3. Excellent sealing element performance, adaptable to harsh working conditions: The flexible graphite-filled PTFE ring of the first sealing device combines the high temperature and corrosion resistance of flexible graphite with the wear resistance and low friction of PTFE; the metal bellows ring of the second sealing device has good elasticity and compensation capability, which can adapt to flange installation deviations and thermal expansion and contraction deformation; the sealing ring is made of oil-resistant and chemically corrosion-resistant rubber. The performance of each sealing element is complementary, enabling it to adapt to harsh working conditions such as high pressure, high temperature, and strong corrosion.

[0017] 4. High assembly precision and tight sealing surface fit: The mounting groove on the sealing structure body has high fitting precision with the sealing gasket and flange body. The flexible graphite-filled PTFE ring fits tightly with the outer periphery of the flange body. The sealing rings on both sides of the metal bellows ring are in close contact with the front side of the inner ring of the flange body, reducing the gap between the sealing surfaces and further improving the sealing effect.

[0018] 5. Reasonable structural design and convenient disassembly and maintenance: Each sealing device and fixing device adopts a modular design. Assembly can be completed by means of snap-fit ​​and bolt connection, which is simple to operate. When disassembling, simply unscrew the fixing bolts and separate the clip and slot to replace or maintain the sealing element, which reduces maintenance costs and time costs.

[0019] This utility model not only effectively overcomes the defects of existing technologies such as low sealing reliability, unstable fixing, lack of multiple sealing, insufficient assembly precision, and lack of gap sealing, but also provides a new type of high-pressure flange sealing structure with reliable sealing, stable structure, adaptability to harsh working conditions, and convenient disassembly and maintenance through an innovative combination of multiple sealing and double fixing structure. It has high practical value and market promotion prospects. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure in Embodiment 1 of this application; Figure 2 This is a schematic diagram of the internal structure in Embodiment 1 of this application; Figure 3 This is a schematic diagram of the connection structure of the sealing gasket, the locking block, and the mounting hole in Embodiment 1 of this application; Figure 4 This is a schematic diagram of the connection structure of multiple sealing sleeves and sealing gaskets in Embodiment 1 of this application.

[0021] Reference numerals: 1. Flexible graphite-filled PTFE ring; 2. Sealing structure body; 3. Sealing sleeve; 4. Fixing bolt; 5. Flange body; 6. Clamping block; 7. Mounting hole; 8. Mounting groove; 9. Fixing groove; 10. Clamping groove; 11. Sealing ring; 12. Sealing gasket; 13. Metal bellows ring. Detailed Implementation

[0022] Example 1 The following is in conjunction with the appendix Figures 1-4 The first embodiment of this application will be described in further detail.

[0023] A sealing structure for a high-pressure flange includes two flange bodies 5, a sealing structure body 2, a first sealing device, a first fixing device, a second fixing device, a second sealing device, and a third sealing device. The two first sealing devices are both disposed on the sealing structure body 2. The two first fixing devices are respectively disposed on the rear side of the two first sealing devices. The two second fixing devices are respectively disposed on the front side of the two first sealing devices. The second sealing device is disposed on the inner wall of the sealing structure body 2. The two third sealing devices are respectively disposed on the two first sealing devices.

[0024] In this embodiment, the first sealing device on the front side includes a flexible graphite-filled polytetrafluoroethylene ring 1. The front side of the sealing structure body 2 is provided with an installation groove 8. The installation groove 8 is provided with a sealing gasket 12. The flexible graphite-filled polytetrafluoroethylene ring 1 is fixedly connected to the top of the sealing gasket 12. The flange body 5 is located between the flexible graphite-filled polytetrafluoroethylene ring 1 and the sealing gasket 12. The flexible graphite-filled polytetrafluoroethylene ring 1 is located on the periphery of the flange body 5. The two first sealing devices are symmetrically distributed with the transverse central axis of the sealing structure body 2 as the center. Specifically, the sealing gasket 12 is a metal-reinforced graphite gasket, which has good sealing performance and compressive strength.

[0025] In this embodiment, the first fixing device on the front side includes a locking block 6, the rear side of the sealing gasket 12 is fixedly connected to the locking block 6, the mounting groove 8 is provided with a locking groove 10, the locking block 6 and the locking groove 10 are engaged and connected, and the two first fixing devices are symmetrically distributed with the transverse central axis of the sealing structure body 2 as the center. Specifically, the locking block 6 is made of elastic plastic material, and has a certain pre-tightening force after locking to ensure a firm connection.

[0026] In this embodiment, the second fixing device at the front end includes multiple fixing grooves 9, and multiple mounting holes 7 are provided on the sealing gasket 12. The multiple fixing grooves 9 are all fixedly connected to the inner wall of the mounting groove 8. The multiple fixing grooves 9 penetrate the through hole of the flange body 5 and the multiple mounting holes 7. The interior of the multiple fixing grooves 9 is threaded with fixing bolts 4. The two second fixing devices are symmetrically distributed with the transverse central axis of the sealing structure body 2 as the center. Specifically, fixing bolt 4 is a high-strength alloy bolt with good tensile and fatigue resistance.

[0027] In this embodiment, the second sealing device includes a metal bellows ring 13, which is fixedly connected inside the through hole of the sealing structure body 2. Both sides of the metal bellows ring 13 are fixedly connected with sealing rings 11, and the two sealing rings 11 are respectively located on the front side of the inner ring of the two flange bodies 5. Specifically, the metal bellows ring 13 is made of stainless steel, which has good elasticity and corrosion resistance, while the sealing ring 11 is made of nitrile rubber, which is suitable for a variety of media.

[0028] In this embodiment, the third sealing device on the front side includes multiple sealing sleeves 3, which are fixedly connected to multiple mounting holes 7 respectively, and are slidably connected to multiple fixing grooves 9. The two third sealing devices are symmetrically distributed with the transverse central axis of the sealing structure body 2 as the center. Specifically, the sealing sleeve 3 is made of polytetrafluoroethylene, which has good sealing performance and wear resistance.

[0029] The implementation principle of the sealing structure of a high-pressure flange in this application embodiment is as follows: During assembly, the sealing gasket 12 is first installed in the mounting groove 8 of the sealing structure body 2 by the engagement of the locking block 6 and the locking groove 10, thus completing the assembly of the first sealing device and the first fixing device. The two flange bodies 5 are placed on the two sealing gaskets 12 respectively, so that the flange bodies 5 are located inside the flexible graphite-filled polytetrafluoroethylene ring 1.

[0030] The fixing groove 9 passes sequentially through the through hole of the flange body 5 and the mounting hole 7 of the sealing gasket 12. Fixing bolts 4 are then screwed into the fixing groove 9 to securely connect the flange body 5 to the sealing structure body 2, completing the assembly of the second fixing device. At this time, the sealing sleeve 3 is fitted over the outside of the fixing groove 9 to seal the gap between the fixing groove 9 and the mounting hole 7.

[0031] The sealing rings 11 on both sides of the metal bellows ring 13 inside the through hole of the sealing structure body 2 are in close contact with the front side of the inner ring of the two flange bodies 5, forming a secondary seal. During operation, the first sealing device seals the outer periphery of the flange body 5, the second sealing device seals the inner ring of the flange body 5, and the third sealing device seals the gap of the fixing device. The multiple sealing devices work together to ensure that the medium does not leak.

[0032] Example 2 The difference between this embodiment and Embodiment 1 is that a layer of flexible graphite tape is wrapped around the outside of the metal corrugated ring 13 to further enhance the sealing performance of the second sealing device.

[0033] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A sealing structure for a high-pressure flange, comprising: Two flange bodies (5) and a sealing structure body (2); characterized in that: The first sealing device is provided in two parts, both of which are located on the sealing structure body (2) and are used to seal the two flange bodies (5). The first fixing device is provided in two parts, which are respectively located on the rear side of the two first sealing devices and are used to fix the two first sealing devices. The second fixing device is provided in two parts. The two second fixing devices are respectively located in front of the two first sealing devices and are used to fix the two flange bodies (5). The second sealing device is located on the inner wall of the sealing structure body (2) and is used to perform secondary sealing work on the flange body (5). There are two third sealing devices, which are respectively installed on the two first sealing devices and are used to seal the gap between the two second fixing devices.

2. The sealing structure of a high-pressure flange according to claim 1, characterized in that: The first sealing device on the front side includes a flexible graphite-filled polytetrafluoroethylene ring (1). The front side of the sealing structure body (2) is provided with an installation groove (8). The installation groove (8) is provided with a sealing gasket (12). The flexible graphite-filled polytetrafluoroethylene ring (1) is fixedly connected to the top of the sealing gasket (12). The flange body (5) is located between the flexible graphite-filled polytetrafluoroethylene ring (1) and the sealing gasket (12). The flexible graphite-filled polytetrafluoroethylene ring (1) is located on the periphery of the flange body (5). The two first sealing devices are symmetrically distributed with the transverse central axis of the sealing structure body (2) as the center.

3. The sealing structure of a high-pressure flange according to claim 2, characterized in that: The first fixing device on the front side includes a locking block (6), the rear side of the sealing gasket (12) is fixedly connected to the locking block (6), the mounting groove (8) is provided with a slot (10), the locking block (6) and the slot (10) are engaged and connected, and the two first fixing devices are symmetrically distributed with the transverse central axis of the sealing structure body (2) as the center.

4. The sealing structure of a high-pressure flange according to claim 3, characterized in that: The second fixing device at the front end includes multiple fixing grooves (9), and multiple mounting holes (7) are provided on the sealing gasket (12). The multiple fixing grooves (9) are all fixedly connected to the inner wall of the mounting groove (8). The multiple fixing grooves (9) penetrate the through hole of the flange body (5) and the multiple mounting holes (7). The interior of the multiple fixing grooves (9) is threaded with fixing bolts (4). The two second fixing devices are symmetrically distributed with the transverse central axis of the sealing structure body (2) as the center.

5. The sealing structure of a high-pressure flange according to claim 4, characterized in that: The second sealing device includes a metal bellows ring (13), which is fixedly connected inside the through hole of the sealing structure body (2). Both sides of the metal bellows ring (13) are fixedly connected with sealing rings (11), and the two sealing rings (11) are located on the front side of the inner ring of the two flange bodies (5).

6. The sealing structure of a high-pressure flange according to claim 5, characterized in that: The front third sealing device includes multiple sealing sleeves (3), which are fixedly connected to multiple mounting holes (7) respectively. The multiple sealing sleeves (3) are slidably connected to multiple fixing grooves (9). The two third sealing devices are symmetrically distributed with the transverse central axis of the sealing structure body (2) as the center.

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