High-pressure natural gas pipeline metal sealing ring self-compensation device

Abstract

The invention belongs to the technical field of natural gas pipelines, and particularly relates to a self-compensation device for a metal sealing ring of a high-pressure natural gas pipeline. An outer connecting sleeve is fixedly connected to the exterior of a first pipeline, and a wear-resistant mechanism is mounted between a first inner connecting sleeve and a second inner connecting sleeve; the space between the first sealing ring and the packing sealing plate and the space between the second sealing ring and the packing sealing plate are filled with rigid packing, and the space between the first sealing ring and the second sealing ring is filled with flexible packing; a first toothed plate is fixedly connected to the exterior of the inserting plate, a sliding rod is slidably connected to the inner side of the translation groove, a clamping mechanism is installed at one end of the sliding rod, and a positioning mechanism is installed at the other end of the sliding rod; according to the device, rolling friction of balls is adopted to replace sliding contact, high-pressure vibration abrasion is greatly reduced, rigid-flexible double-filler combination elastically responds to deformation, continuous pressing of a sealing face is maintained, internal pressure impact is resisted through the right-angle toothed plate meshing self-locking design, and zero-leakage stable connection under the extreme working condition is achieved in combination with three-stage insertion rod positioning and bolt fastening.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of natural gas pipelines, in particular to a self-compensation device for a metal sealing ring of a high-pressure natural gas pipeline. BACKGROUND

[0002] In the field of high-pressure natural gas pipeline transportation, the sealing performance of the pipeline connection directly relates to the safety and reliability of the entire system. Traditional flange connections use rubber or metal gasket sealing, but under high-pressure, high-frequency vibration and temperature change conditions, the sealing material is prone to aging and wear, increasing the risk of gas leakage. In addition, although the metal sealing ring in the prior art has high pressure resistance, it lacks self-compensation ability and is prone to sealing failure due to pipeline deformation or vibration after long-term use, requiring frequent downtime maintenance, which affects the transportation efficiency. Currently, some improvement schemes increase the pre-tightening force to improve the sealing effect, but this exacerbates the stress concentration of the flange bolts, which may cause connection loosening or even pipe explosion accidents under high-pressure impact. Therefore, there is an urgent need for a sealing device that combines anti-wear, self-adaptive compensation, and anti-impact shedding capabilities to meet the long-term stable operation requirements of high-pressure natural gas pipelines under harsh working conditions.

[0003] The existing high-pressure pipeline sealing device mainly has three defects: first, the metal sealing ring is in rigid contact with the pipeline, and high-pressure vibration causes severe friction wear, shortening the service life; second, the traditional filler lacks elastic deformation ability and cannot compensate for the sealing gap caused by the micro-displacement of the pipeline; third, the flange connection relies on single locking of the bolts, and high-pressure gas impact can cause the threads to loosen, leading to sealing failure. These problems make it difficult for the existing device to balance sealing reliability, wear resistance, and impact resistance, posing a major safety hazard to the safe operation of high-pressure natural gas pipelines. Therefore, a self-compensation device for a metal sealing ring of a high-pressure natural gas pipeline is proposed. SUMMARY

[0004] To solve the above problems, the present application proposes a self-compensation device for a metal sealing ring of a high-pressure natural gas pipeline to more accurately solve the problems raised in the background art.

[0005] The present application is achieved by the following technical solutions: The application provides a high-pressure natural gas pipeline metal sealing ring self-compensation device, which comprises a first pipeline, a second pipeline, a mounting plate and a mounting seat, an external connecting sleeve is fixedly connected to the outside of the first pipeline, a first flange is fixedly connected to the outside of the external connecting sleeve, a second flange is fixedly connected to the outside of the second pipeline, a first inner connecting sleeve is fixedly connected to the outside of the external connecting sleeve, a second inner connecting sleeve is fixedly connected to the outside of the second flange, two groups of symmetrical wear-resistant mechanisms are arranged between the first inner connecting sleeve and the second inner connecting sleeve, two groups of symmetrical packing seal plates are fixedly connected to the outside of the second inner connecting sleeve, the two groups of packing seal plates are respectively attached to the external connecting sleeve and the first inner connecting sleeve, a first sealing ring and a second sealing ring are arranged on the outside of the second inner connecting sleeve, rigid packing is filled between the first sealing ring and the packing seal plate and between the second sealing ring and the packing seal plate, and flexible packing is filled between the first sealing ring and the second sealing ring; the mounting plate is inserted into the outside of the second flange, the mounting seat is inserted into the outside of the first flange, a cavity is formed in the inside of the mounting seat, a plug plate is fixedly connected to the outside of the mounting plate and slidably connected to the inside of the cavity, a first tooth plate is fixedly connected to the outside of the plug plate, a translation groove is formed in the outside of the mounting seat, a sliding rod is slidably connected to the inside of the translation groove, a clamping mechanism is arranged at one end of the sliding rod, and a positioning mechanism is arranged at the other end of the sliding rod.

[0006] Preferably, connecting bolts are threadedly connected between the first flange and the second flange, two groups of transversely arranged fastening nuts are threadedly connected to the outside of the connecting bolts, one group of the fastening nuts abuts against one side of the second flange, and the two groups of fastening nuts abut against each other.

[0007] Preferably, the outer diameter of the second inner connecting sleeve is smaller than that of the first inner connecting sleeve, and the second inner connecting sleeve is located on the inside of the first inner connecting sleeve.

[0008] Preferably, the wear-resistant mechanism comprises first fixing rings and second fixing rings, the second fixing rings are fixedly connected to the inside of the second inner connecting sleeve, one group of the first fixing rings is fixedly connected to the inside of the external connecting sleeve, and the other group of the first fixing rings is fixedly connected to the inside of the first inner connecting sleeve.

[0009] Preferably, a first stepped groove is formed in the inside of the first fixing ring, a second stepped groove is formed in the outside of the second fixing ring, the first fixing ring and the second fixing ring are limited in position by the first stepped groove and the second stepped groove, an installation groove is formed in the outside of the second stepped groove, and rolling balls are rollingly connected between the installation groove and the first stepped groove.

[0010] Preferably, the first flange and the second flange are externally provided with clamping grooves, the mounting plate and the mounting seat are externally fixedly connected with positioning inserting rods which are inserted into the clamping grooves.

[0011] Preferably, the clamping mechanism comprises a connecting plate and a second toothed plate, the connecting plate is fixedly connected with the sliding rod, the second toothed plate is fixedly connected with the connecting plate, and the second toothed plate is engaged with the first toothed plate.

[0012] Preferably, the sawtooth of the second toothed plate and the first toothed plate is a right triangle, and the right angle side of the sawtooth of the second toothed plate and the first toothed plate is in abutment in a direction out of the cavity when the inserting plate is pulled out.

[0013] Preferably, the positioning mechanism comprises a positioning plate and positioning bolts, the positioning plate is fixedly connected with the sliding rod and is slidingly connected with the outside of the mounting seat, and the positioning bolts are threadedly connected with the outside of the positioning plate and embedded in the inside of the mounting seat.

[0014] Preferably, the positioning bolts are arranged in several groups and symmetrically.

[0015] Compared with the prior art, the present application provides a high-pressure natural gas pipeline metal sealing ring self-compensation device, which has the following beneficial effects: 1. The high-pressure natural gas pipeline metal sealing ring self-compensation device significantly improves the sealing reliability and service life of high-pressure natural gas pipeline connections. Through the design of ball rolling friction, the wear degree of traditional metal sealing rings under high-pressure vibration conditions is effectively reduced, and the decline in sealing performance caused by long-term friction is avoided. The rigid and flexible filler combination design can adapt to pipeline deformation. The flexible filler produces elastic compensation when the pressure fluctuates, and the rigid filler maintains stable sealing pressure. The synergistic effect of the two ensures excellent sealing effect under various working conditions. This design not only solves the problem of easy aging and failure of traditional sealing materials, but also greatly prolongs the maintenance period and reduces the pipeline operation cost.

[0016] 2. The high-pressure natural gas pipeline metal sealing ring self-compensation device solves the problem of impact stability at the connection of high-pressure pipelines. The three-level mechanical interlocking structure cooperates with precise positioning of the inserting rod, self-locking engagement of the right-angle toothed plate, and multi-point bolt fastening to form multiple impact protection. In particular, the self-locking feature of the right-angle toothed plate can produce a mechanical reverse stop effect when the internal pressure of the pipeline suddenly increases, effectively preventing connection loosening. This design fundamentally overcomes the defects of traditional flange connections that rely solely on bolt fastening, significantly improving the safety and stability of the pipeline system under extreme working conditions, and providing a strong guarantee for the long-term reliable operation of high-pressure natural gas pipelines. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a schematic diagram of the overall structure of the present application; Figure 2 is a partial structure front cross-sectional view of the present application; Figure 3 is a partial structure front cross-sectional view of the present application; Figure 2 is an enlarged view of the structure at A in the middle; Figure 4 is a schematic diagram of the second overall structure of the present application; Figure 5 is a partial structure front cross-sectional view of the present application; Figure 4 is an enlarged view of the structure at B in the middle; Figure 6 is a partial structure front cross-sectional view of the present application; Figure 1 is an enlarged view of the structure at C in the middle; Figure 7 is a partial structure front cross-sectional view of the present application; Figure 1 is an enlarged view of the structure at D in the middle; Figure 8 is a partial structure front cross-sectional view of the present application; Figure 9 is a partial structure front cross-sectional view of the present application; Figure 8 is an enlarged view of the structure at E in the middle; Figure 10 is a partial structure front cross-sectional view of the present application; Figure 8 is an enlarged view of the structure at F in the middle.

[0018] In the figure: 1, first pipe; 2, second pipe; 3, external sleeve; 4, first flange; 5, second flange; 6, connecting bolt; 7, fastening nut; 8, first internal sleeve; 9, second internal sleeve; 10, first fixing ring; 11, second fixing ring; 12, first stepped groove; 13, second stepped groove; 14, mounting groove; 15, ball; 16, packing seal plate; 17, first sealing ring; 18, second sealing ring; 19, rigid packing; 20, flexible packing; 21, mounting plate; 22, mounting seat; 23, clamping groove; 24, positioning plug; 25, cavity; 26, plug plate; 27, first toothed plate; 28, translation groove; 29, slide rod; 30, connecting plate; 31, second toothed plate; 32, positioning plate; 33, positioning bolt. DETAILED DESCRIPTION

[0019] In order to more clearly and completely illustrate the technical solutions of the present application, the present application will be further described below in conjunction with the accompanying drawings.

[0020] Example One

[0021] As Figures 1-3As shown in the figure, an embodiment of the present invention proposes a self-compensating device for a high-pressure natural gas pipeline metal sealing ring, including a first pipeline 1, a second pipeline 2, a mounting plate 21, and a mounting base 22. An external sleeve 3 is fixedly connected to the outside of the first pipeline 1. The external sleeve 3 serves as a transition component for the connection between the first pipeline 1 and the flange. It has a sealing structure installation space inside. A first flange 4 is fixedly connected to the outside of the external sleeve 3. The first flange 4 serves as the main load-bearing component of the pipeline connection. Its end face is machined with a precise sealing mating surface. A second flange 5 is fixedly connected to the outside of the second pipeline 2. The second flange 5 and the first flange 4 together form the basic framework of the pipeline connection. A connecting bolt 6 is threadedly connected between the first flange 4 and the second flange 5. The connecting bolt 6 serves as the core fastener of the flange connection. Its strength is directly related to the reliability of the pipeline connection. Two sets of transversely arranged fastening nuts 7 are threadedly connected to the outside of the connecting bolt 6. The fastening nuts 7 adopt a double-nut anti-loosening design. One set of fastening nuts 7 abuts against one side of the second flange 5 to provide initial pre-tightening force, and the two sets of fastening nuts 7 abut against each other to form a mechanical interlock, effectively preventing the threads from loosening due to vibration.

[0022] like Figure 2 as well as Figure 3 As shown, the outer sleeve 3 is fixedly connected to the first inner sleeve 8. The first inner sleeve 8 serves as the main supporting component of the sealing structure. Its inner diameter is precision machined to ensure the sealing fit accuracy. The second flange 5 is fixedly connected to the second inner sleeve 9. The second inner sleeve 9 serves as the main body of the movable sealing component. Its outer surface is specially hardened to improve wear resistance. The outer diameter of the second inner sleeve 9 is smaller than the outer diameter of the first inner sleeve 8 to form a fitting gap. The second inner sleeve 9 is located inside the first inner sleeve 8 to form a nested sealing structure. This design allows the pipeline to undergo slight displacement under stress without affecting the sealing performance.

[0023] like Figure 2 as well as Figure 3As shown, two groups of symmetrical wear-resistant mechanisms are installed between the first inner sleeve 8 and the second inner sleeve 9, the wear-resistant mechanism includes a first fixed ring 10 and a second fixed ring 11, the first fixed ring 10 is used as a rolling support fixed component, and the material is selected from high-strength alloy steel, and the second fixed ring 11 is fixedly connected to the inner side of the second inner sleeve 9 as a movable component, one group of first fixed rings 10 are fixedly connected to the inner side of the outer sleeve 3 to provide axial support, and the other group of first fixed rings 10 are fixedly connected to the inner side of the first inner sleeve 8 to form double protection, the inner side of the first fixed ring 10 is provided with a first stepped groove 12, and the outer side of the second fixed ring 11 is provided with a second stepped groove 13, the stepped groove structure provides an accurate running track for the ball 15, and the first fixed ring 10 and the second fixed ring 11 are limited by the first stepped groove 12 and the second stepped groove 13 to ensure the movement accuracy, the outer side of the second stepped groove 13 is provided with a mounting groove 14, the mounting groove 14 is used as the installation reference surface of the ball 15, and the depth is accurately calculated to ensure the contact angle of the ball 15, the ball 15 is made of high-hardness ceramic material, and the sliding friction is converted into rolling friction, which significantly reduces the wear of the sealing surface.

[0024] As shown in the figure, Figure 3 The outer side of the second inner sleeve 9 is fixedly connected with two groups of symmetrical packing seal plates 16, the packing seal plate 16 is used as a separation component of the packing cavity, the edge is chamfered to avoid damage to the packing, and the two groups of packing seal plates 16 are respectively attached to the outer sleeve 3 and the first inner sleeve 8 to form a sealing boundary, the outer side of the second inner sleeve 9 is provided with a first sealing ring 17 and a second sealing ring 18, the sealing ring is made of special composite material and has elasticity and wear resistance, the first sealing ring 17 and the packing seal plate 16 and the second sealing ring 18 and the packing seal plate 16 are filled with rigid packing 19, the rigid packing 19 is selected from metal powder composite material to ensure the sealing stability under high pressure, and the first sealing ring 17 and the second sealing ring 18 are filled with flexible packing 20, the flexible packing 20 is made of graphite-based material and can provide elastic compensation when the pipeline deforms, and the combination of rigid and flexible packing layout realizes the perfect combination of dynamic and static sealing.

[0025] In this embodiment, when the pipeline is subjected to severe pressure fluctuation, the device ensures the stability of the seal through a triple synergistic design. First, the first fixed ring 10 and the second fixed ring 11 in the wear-resistant mechanism are embedded with each other through a stepped groove structure, and the first stepped groove 12 and the second stepped groove 13 form a rolling track, so that the rolling ball 15 can freely roll in the installation groove 14, converting the sliding friction of the pipeline axial displacement into rolling friction, significantly reducing the metal wear caused by high-pressure vibration. Second, the sealing self-compensation system is composed of a flexible filler 20 and a rigid filler 19 to form a dynamic response layer. When the pressure suddenly increases and causes the second inner sleeve 9 and the outer sleeve 3 to move slightly, the flexible filler 20 is compressed to produce elastic deformation, actively filling the expansion gap between the first sealing ring 17 and the second sealing ring 18, while the rigid filler 19 remains dense under the constraint of the filler sealing plate 16, preventing gas from leaking along the radial direction. This combination of rigidity and flexibility not only adapts to the deformation of the pipeline but also maintains the continuous compression force of the sealing surface, achieving zero leakage self-compensation under pressure fluctuation.

[0026] Example Two

[0027] As shown in Figures 1-10 , on the basis of example one, the mounting plate 21 is inserted into the outside of the second flange 5 as the positioning reference of the connection structure, and the mounting seat 22 is inserted into the outside of the first flange 4 to form a complete connection frame. The outside of the first flange 4 and the second flange 5 is provided with a clamping groove 23, and the clamping groove 23 is designed as a dovetail groove to ensure positioning accuracy. The outside of the mounting plate 21 and the mounting seat 22 is fixedly connected with a positioning plug rod 24, and the positioning plug rod 24 is subjected to quenching treatment to improve wear resistance. The positioning plug rod 24 is inserted into the inside of the clamping groove 23 to realize rapid and accurate positioning. This plug-in design greatly simplifies the on-site installation process.

[0028] As shown in Figure 8 and Figure 10 , the inside of the mounting seat 22 is provided with a cavity 25, and the size of the cavity 25 is accurately calculated to ensure the activity gap of the plug plate. The outside of the mounting plate 21 is fixedly connected with a plug plate 26, and the plug plate 26 is formed by laser cutting of high-strength steel plate to ensure size accuracy. The plug plate 26 is slidingly connected to the inside of the cavity 25 to realize axial positioning. The outside of the plug plate 26 is fixedly connected with a first tooth plate 27, and the tooth shape of the first tooth plate 27 is specially designed to optimize the stress distribution. The outside of the mounting seat 22 is provided with a translation slot 28, and the two sides of the translation slot 28 are polished to reduce the friction coefficient. The inside of the translation slot 28 is slidingly connected with a slide rod 29, and the surface of the slide rod 29 is chrome-plated to improve wear resistance and corrosion resistance.

[0029] As shown in Figure 10As shown, one end of the slide rod 29 is provided with a clamping and mechanism, which includes a connecting plate 30 and a second tooth plate 31. The connecting plate 30 is fixedly connected with the slide rod 29 to form a rigid transmission structure. The second tooth plate 31 is fixedly connected with the connecting plate 30 to ensure the shortest force transmission path. The second tooth plate 31 is engaged with the first tooth plate 27 to form a mechanical self-locking. The sawtooth of the second tooth plate 31 and the first tooth plate 27 are all in the shape of a right triangle. Such a tooth shape design can produce a self-enhancing effect when stressed. The right angle edges of the sawtooth of the second tooth plate 31 and the first tooth plate 27 abut in the direction of the plug plate 26 being pulled out of the cavity 25. Such an arrangement makes the larger the pressure in the pipeline, the tighter the engagement of the tooth plates, thereby forming a perfect pressure self-adaptive locking mechanism.

[0030] As shown in Figure 1 and Figure 7 the other end of the slide rod 29 is provided with a positioning mechanism, which includes a positioning plate 32 and a positioning bolt 33. The positioning plate 32 is fixedly connected with the slide rod 29 to form an integral movement component. The positioning plate 32 is slidingly connected to the outside of the mounting seat 22 to achieve precise positioning. The positioning bolt 33 is threadedly connected to the outside of the positioning plate 32 to provide a final locking force. The positioning bolt 33 is embedded in the inside of the mounting seat 22 to form an anti-loosening structure. The number of the positioning bolts 33 is several groups and is symmetrically arranged. Such a multi-bolt uniform distribution design ensures the uniform distribution of the locking force and avoids the deformation problem caused by local stress concentration.

[0031] In the embodiment, the quick installation and high-pressure resistance of the device depend on the multiple mechanical interlocking design. During installation, the positioning plug rod 24 is accurately inserted into the clamping groove 23 outside the flange, the guide mounting plate 21 is axially aligned with the mounting seat 22, the plug plate 26 carrying the first tooth plate 27 is slid into the cavity 25, the tooth plate is engaged and locked, the operator pushes the slide rod 29 transversely to drive the second tooth plate 31 at the end of the connecting plate 30 to engage with the right-angle sawtooth of the first tooth plate 27, i.e., the right-angle edges of the sawtooth are directed to the direction of the plug plate 26 exiting, forming a mechanical reverse stop. When the pressure in the pipeline suddenly increases to generate an outward pushing force, the right-angle edges of the sawtooth produce a self-locking effect, completely inhibiting the plug plate 26 from being pulled out of the cavity 25. In the final positioning stage, the positioning plate 32 is longitudinally slid to tightly abut against the side wall of the mounting seat 22, and the symmetrically arranged positioning bolts 33 are screwed to complete rigid fixation. The three-stage locking, i.e., plug rod positioning + tooth plate self-locking + bolt compression, greatly improves the impact resistance of the connecting bolt 6, ensures that the flange connection does not loosen under extreme working conditions, thereby maintaining the self-compensation space of the sealing ring and the overall structural stability, and eliminating the risk of pipe explosion.

[0032] It should be understood that all the details provided above are merely exemplary and do not limit the present specification. Although not explicitly described, one skilled in the art can make various modifications, improvements and corrections to the present specification. Such modifications, improvements and corrections are suggested in the present specification, and still belong to the spirit and scope of the exemplary embodiments of the present specification. Also, specific words are used in the present specification to describe the embodiments of the present specification. For example, "one embodiment", "an embodiment", and / or "some embodiments" mean a certain feature, structure or characteristic related to at least one embodiment of the present specification. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "one alternative embodiment" mentioned in different places in the present specification does not necessarily mean the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present specification can be properly combined. In addition, unless explicitly stated in the claims, the order of processing elements and sequences, the use of numerical letters, or the use of other names in the present specification are not intended to limit the order of processes and methods of the present specification.

[0033] Finally, it should be noted that the above only describes the preferred embodiments of the present application, and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can modify, improve and correct the technical solutions described in the foregoing embodiments, or make equivalent replacements to some technical features. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A self-compensating device for high pressure natural gas pipeline metal seal rings, characterized by, The utility model relates to a pipeline connection device, including first pipeline (1), second pipeline (2), mounting plate (21) and mounting seat (22), the outside fixed connection of first pipeline (1) has external connection sleeve (3), the outside fixed connection of external connection sleeve (3) has first flange (4), the outside fixed connection of second pipeline (2) has second flange (5), the outside fixed connection of external connection sleeve (3) has first inner sleeve (8), the outside fixed connection of second flange (5) has second inner sleeve (9), two groups of symmetrical arrangement's wear -resisting mechanism are installed between first inner sleeve (8) with second inner sleeve (9), the outside fixed connection of second inner sleeve (9) has two groups of symmetrical arrangement's packing seal plate (16), and two groups packing seal plate (16) respectively with external connection sleeve (3) and first inner sleeve (8) are pasted, the outside sleeve of second inner sleeve (9) has first sealing ring (17) and second sealing ring (18), and first sealing ring (17) with packing seal plate (16) between and second sealing ring (18) with packing seal plate (16) between all fill rigid packing (19), and first sealing ring (17) and second sealing ring (18) between fill flexible packing (20), the outside of mounting plate (21) is inserted in second flange (5), the outside of mounting seat (22) is inserted in first flange (4), the inside of mounting seat (22) is equipped with cavity (25), the outside fixed connection of mounting plate (21) has plugboard (26), and plugboard (26) sliding connection is in the inside of cavity (25), the outside fixed connection of plugboard (26) has first toothed plate (27), the outside of mounting seat (22) is equipped with translation slot (28), the inside sliding connection of translation slot (28) has slide rod (29), one end of slide rod (29) is installed with clamp and mechanism, and the other end of slide rod (29) is installed with positioning mechanism.

2. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 1, characterized in that, The threaded connection of first flange (4) with second flange (5) has connecting bolt (6), the outside threaded connection of connecting bolt (6) has two groups of transverse arrangement's fastening nut (7), one group fastening nut (7) is located at one side of second flange (5), and two groups fastening nut (7) are located at the abutted limit between.

3. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 1, characterized in that, The outer diameter of second inner sleeve (9) is less than the outer diameter of first inner sleeve (8), and second inner sleeve (9) is located in the inside of first inner sleeve (8).

4. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 1, characterized in that, The wear -resisting mechanism includes first fixed ring (10) and second fixed ring (11), the inside fixed connection of second fixed ring (11) in second inner sleeve (9), one group first fixed ring (10) is fixedly connected to the inside of external connection sleeve (3), and the other group first fixed ring (10) is fixedly connected to the inside of first inner sleeve (8).

5. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 4, characterized in that, The inner side of the first fixed ring (10) is provided with a first stepped groove (12), the outer side of the second fixed ring (11) is provided with a second stepped groove (13), and the first fixed ring (10) and the second fixed ring (11) are limited by abutting the first stepped groove (12) and the second stepped groove (13), the outer side of the second stepped groove (13) is provided with a mounting groove (14), and the mounting groove (14) and the first stepped groove (12) are connected with a ball (15).

6. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 1, characterized in that, The outer side of the first flange (4) and the second flange (5) is provided with a clamping groove (23), the outer side of the mounting plate (21) and the mounting seat (22) is fixedly connected with a positioning plug rod (24), and the positioning plug rod (24) is inserted into the inner side of the clamping groove (23).

7. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 1, characterized in that, The clamping mechanism comprises a connecting plate (30) and a second toothed plate (31), the connecting plate (30) is fixedly connected with the slide rod (29), the second toothed plate (31) is fixedly connected with the connecting plate (30), and the second toothed plate (31) is engaged with the first toothed plate (27).

8. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 7, characterized in that, The sawteeth of the second toothed plate (31) and the first toothed plate (27) are all right-angled triangles, and the abutting direction of the right-angled sides of the sawteeth of the second toothed plate (31) and the first toothed plate (27) is the direction of the plug plate (26) being pulled out of the cavity (25).

9. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 1, characterized in that, The positioning mechanism comprises a positioning plate (32) and a positioning bolt (33), the positioning plate (32) is fixedly connected with the slide rod (29), and the positioning plate (32) is slidingly connected with the outer side of the mounting seat (22), the positioning bolt (33) is threadedly connected with the outer side of the positioning plate (32), and the positioning bolt (33) is embedded in the inner side of the mounting seat (22).

10. A self-compensating device for high-pressure natural gas pipeline metal seal rings according to claim 9, characterized in that, The number of the positioning bolts (33) is several groups and is symmetrically arranged.

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