Argon filling sealing device and sealing method for welding

Abstract

An argon-filled sealing device for welding, comprising two support frames and an airbag sealing assembly; the support frame comprising a central support member, a support arm, and a drive device; the support arm comprising a fixed arm and a movable arm slidably connected to the fixed arm, a ball supported by a first elastic member being provided in a limiting groove at the end of the movable arm; the drive device comprising a support shaft, a drive sleeve, a fine-tuning member, and a drive rod, the two ends of the drive rod being hinged to the movable arm and the fine-tuning member respectively; the sliding path of the fine-tuning member is parallel to the moving path of the drive sleeve, and a retractable first stopper and a fixed second stopper are provided on the drive sleeve along the sliding path of the fine-tuning member; the first stopper is remotely controlled by a pull rope. The present invention is used to solve the technical problem that the current sealing device is difficult to be pulled out after welding is completed due to high friction.

Description

Technical Field

[0001] The invention belongs to the technical field of pipeline welding, and particularly relates to an argon filling sealing device for welding and a sealing method. Background Art

[0002] For thermal power generation, improving unit operating parameters and developing supercritical and ultra-supercritical units are currently key research areas. Among the key components of supercritical and ultra-supercritical units, P92 steel is widely used in steam piping, superheaters, and reheaters. During the processing of P92 steel piping, segmented pipes must be connected by welding, often using argon arc welding. During argon arc welding, the pipe is filled with argon gas to prevent any reactions between the metals in the weld zone and air, thereby achieving high-quality welds.

[0003] The prior art discloses a patent application with the patent name "A welding argon-filled sealing device", application number 202022308859.2, and authorization announcement date of 2021.06.29, including an I-shaped seal and moisturizing cotton. The moisturizing cotton is fixedly arranged on both sides of the I-shaped seal, and the maximum outer diameter of the I-shaped seal is smaller than the inner diameter of the pipe to be welded, and the outer diameter of the moisturizing cotton is not smaller than the inner diameter of the pipe to be welded. An air inlet nozzle is provided on one side edge of the I-shaped seal; the welding argon-filled sealing device described in the present invention can use the I-shaped seal and moisturizing cotton to form a sealed cavity in the area to be welded, and then use the inflation nozzle to fill the sealed cavity with argon of a certain pressure. Compared with the existing method of filling the entire pipe with argon, it greatly saves the amount of argon filled and reduces production costs.

[0004] However, in the above-mentioned prior art, when removing the plugging device after welding, the friction between the moisturizing cotton and the inner wall of the pipe is large, making it difficult to pull it out. At the same time, the moisturizing cotton can easily scratch the inner wall of the pipe, affecting the quality of the pipe. Therefore, a new plugging device is urgently needed to solve the above problems. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide an argon-filled sealing device and a sealing method for welding, which are used to solve the technical problem that the current sealing device is difficult to be pulled out due to high friction after welding.

[0006] To achieve the above-mentioned object, the technical solution of the present invention is as follows: an argon-filled plugging device for welding, which comprises two support frames and an airbag plugging assembly detachably connected to the two support frames for plugging the pipeline;

[0007] The support frame includes a central support member, at least three retractable support arms, and a driving device for driving the support arms to retract;

[0008] The support arms are evenly arranged along the circumference of the central support member;

[0009] The support arm includes a fixed arm and a movable arm slidably connected to the fixed arm, and a ball supported by a first elastic member is provided in a limiting groove at the end of the movable arm;

[0010] The driving device includes a support shaft rotatably connected to the central support member, a driving sleeve threadedly connected to the support shaft, a fine-tuning member slidably connected to the driving sleeve, and a driving rod, wherein both ends of the driving rod are respectively hinged to the movable arm and the fine-tuning member;

[0011] The sliding path of the fine-tuning member is parallel to the moving path of the driving sleeve. A retractable first stopper and a fixed second stopper are provided on the driving sleeve along the sliding path of the fine-tuning member. The first stopper extends to stop the fine-tuning member and retracts to release the fine-tuning member. The first stopper is located on a side of the second stopper close to the support arm.

[0012] The first stopper is remotely controlled by a pull cord;

[0013] The first stopper is slidably connected to a countersunk hole provided on the driving sleeve. A second elastic member is provided at the bottom of the countersunk hole to support the first stopper, thereby realizing the extension and retraction of the first stopper.

[0014] The argon-filled sealing device for welding is described as follows: a through hole parallel to the central axis of the drive sleeve is provided near the bottom of the countersunk hole, a connecting hole is provided between the bottom of the countersunk hole and the through hole, a pull rope is connected to the bottom of the first stopper, and the other end of the pull rope passes through the through hole, so that the first stopper can be remotely driven by the pull rope.

[0015] In the argon-filled sealing device for welding, the pull rope is split into two and passes through the two ends of the through hole respectively.

[0016] In the argon-filled sealing device for welding, a guide roller is provided in the through hole, and the pull rope extends from the countersunk hole to the through hole and then passes around the guide roller to realize the turning of the pull rope.

[0017] In the argon-filled sealing device for welding, the fine-tuning member adopts a fine-tuning sleeve, which is sleeved on the driving sleeve and drives multiple driving rods at the same time.

[0018] The argon-filled sealing device for welding, the driving device also includes at least two limit rods connected to the central support member, the limit rods are parallel to the support shaft; the limit rods pass through the driving sleeve to achieve a sliding connection.

[0019] The argon-filled sealing device for welding is characterized in that a connecting pipe is passed between the two airbag sealing components, and a pressure valve is provided on the connecting pipe; a threaded sleeve that cooperates with the thread of the support shaft is provided at the center of one airbag sealing component, and a non-threaded sleeve with a smooth inner wall is provided at the center of the other airbag sealing component, which can be loosely mounted on the support shaft.

[0020] The argon-filled sealing device for welding has the airbag sealing component of the non-threaded sleeve and is provided with a connecting ear for connecting with a corresponding drawstring.

[0021] In the argon-filled sealing device for welding, the two airbag sealing assemblies are connected by a telescopic rod.

[0022] A method for sealing an argon-filled sealing device for welding, the method comprising the following steps:

[0023] (1) Place the support frame in two pipes to be welded, rotate the support shaft, move the drive sleeve and extend the movable arm through the drive rod. The end of the movable arm is pressed against the inner wall of the pipe in a surface contact manner, increasing the friction surface and improving the support stability;

[0024] (2) Connect an extension cord to the pull ring and extend the extension cord out of the pipe to pull out the support frame after welding is completed;

[0025] (3) Connect the two airbag sealing components to the two support frames respectively, inflate them to achieve sealing, and then weld them;

[0026] (4) After the welding is completed, the annular airbag is deflated, and the first stopper is remotely controlled to retract by pulling the extension cord. Under the rebound action of the first elastic member, the movable arm is pushed, and then the fine-tuning member is pushed to move toward the second stopper;

[0027] (5) At this time, the balls support the inner wall of the pipe. The balls can roll to reduce the friction between the balls and the pipe wall, making it easier to pull out the support frame. During the entire pulling process, the support frame is supported on the inner wall of the pipe, and there will be no problems of skewing or jamming, making it smoother to pull out. Beneficial effects

[0028] 1. The present invention supports two support frames in two pipes near the ends that need to be welded, rotates the support shaft relative to the drive sleeve, and moves the drive sleeve relative to the support shaft. Under the driving action of the drive rods hinged at both ends, the movable arm extends relative to the fixed arm, and the end of the movable arm presses against the inner wall of the pipe to achieve support (at this time, the ball at the end of the movable arm shrinks in the limit groove due to pressure, and the first elastic member is in a compressed state). Two airbag sealing assemblies are respectively connected to the two support frames, and sealing is achieved by inflating the airbag sealing assemblies. Argon gas is filled between the two airbag sealing assemblies to reduce the influence of air on welding.

[0029] 2. After welding is completed, the present invention deflates and shrinks the airbag sealing assembly, and the first stopper is remotely controlled to shrink by a pull rope, thereby losing its stopping effect on the fine-tuning part. Under the action of the rebound force of the first elastic part, the movable arm shrinks relative to the fixed arm, and the fine-tuning part moves relative to the driving sleeve to the position of the second stopper (away from the support arm). At this time, the ball bearings are supported on the side wall of the pipe, and the support frame is still in a supporting state. However, since the ball bearings can rotate relative to the side wall of the pipe, the friction force is reduced, and the support frame can be pulled out with less force. During the pulling-out process, the support frame is always in a state of supporting the pipe wall, avoiding the phenomenon of it skewing and getting stuck, making it easier to remove the sealing device. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of an embodiment of an argon-filled plugging device for welding;

[0031] Figure 2 This is a schematic cross-sectional view of a support frame of an embodiment of an argon-filled plugging device for welding;

[0032] Figure 3 for Figure 2 A in the middle is an enlarged schematic diagram;

[0033] Figure 4 for Figure 2 The enlarged schematic diagram of point B in the middle;

[0034] Figure 5 This is a side view of an airbag sealing component of an embodiment of an argon-filled sealing device for welding.

[0035] in, Figure 1-5In the figure, 1-support arm, 11-fixed arm, 12-movable arm, 121-limiting groove, 122-ball, 123-first elastic member, 2-center support ring, 21-bearing assembly, 3-driving device, 31-support shaft, 32-limiting rod, 33-driving sleeve, 331-first stopper, 332-countersunk hole, 333-second elastic member, 334-through hole, 335-pull rope, 336-pull ring, 337-second stopper, 34-fine-tuning member, 35-driving rod, 4-airbag sealing assembly, 41-sealing disk, 42-annular airbag, 43-air inlet, 44-non-threaded sleeve, 45-connecting ear, 46-threaded sleeve, 5-connecting pipe, 6-pressure valve, 7-telescopic rod. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments, and do not limit the scope of the present invention.

[0037] Specific implementation method one, as Figure 1-5 As shown, a welding argon-filled plugging device comprises two support frames and two airbag plugging assemblies 4. The support frames are used to support the end of the pipe near the welding target, providing support and positioning for the airbag plugging assemblies 4. The two airbag plugging assemblies 4 are detachably connected to the two support frames. After the support frames are connected to the pipe, the airbag plugging assemblies 4 are connected separately. After the airbag plugging assemblies 4 are inflated, the pipe is plugged. Argon gas is then filled between the two airbag plugging assemblies 4 for protection.

[0038] The support frame includes a central support member, a support arm 1 and a drive device 3. The support arm 1 is of a retractable type, with at least three provided, evenly arranged along the circumference of the central support member, and arranged perpendicular to the connecting surface. The support arm 1 includes a fixed arm 11 connected to the central support member and a movable arm 12 slidably connected to the fixed arm 11. A limiting groove 121 is provided at the end of the movable arm 12, and a ball 122 is supported in the limiting groove 121 by a first elastic member 123; a limiting ring is provided at the opening of the limiting groove 121 to limit the ball 122 to prevent it from falling out, and to allow the ball 122 to be partially exposed. In this embodiment, there are four support arms 1; the first elastic member 123 adopts a compression spring.

[0039] In this embodiment, the central support member is a central support ring 2, which facilitates the uniform arrangement of the support arms 1 along the circumferential direction thereon.

[0040] The driving device 3 includes a support shaft 31, a driving sleeve 33, a fine-tuning member 34, and a driving rod 35. The support shaft 31 is rotatably connected to the central support ring 2 via the bearing assembly 21 and is coaxially arranged with the central support ring 2. The driving sleeve 33 is connected to the support shaft 31 by threaded engagement, and the relative rotation of the two causes the driving sleeve 33 to move along the support shaft 31. The fine-tuning member 34 is slidably connected to the driving sleeve 33, and its sliding path is parallel to the moving path of the driving sleeve 33. One end of the driving rod 35 is hinged to the fine-tuning member 34, and the other end is hinged to the movable arm 12. This allows the driving sleeve 33 to move closer to the support arm 1 when the driving sleeve 33 approaches the support arm 1, and the movable arm 12 is extended under the action of the driving rod 35. When the driving sleeve 33 moves away from the support arm 1, the fine-tuning member 34 is moved away from the support arm 1, and the movable arm 12 is retracted under the action of the driving rod 35. A first stopper 331 and a second stopper 337 are provided on the drive sleeve 33 along the sliding path of the fine-tuning member 34, engaging with the fine-tuning member 34. The first stopper 331 is located on the side of the second stopper 337 closer to the support arm 1. The second stopper 337 is fixed. The first stopper 331 is retractable, blocking the fine-tuning member 34 when extended and releasing it when retracted. Furthermore, the extension and retraction of the first stopper 331 can be remotely controlled by pulling the lever 335.

[0041] In this embodiment, the fine-tuning member 34 is a fine-tuning sleeve that fits over the drive sleeve 33. Multiple drive rods 35 are hingedly connected to the fine-tuning sleeve, enabling synchronous actuation of the multiple drive rods 35. Accordingly, two first stoppers 331 can be provided, symmetrically positioned, or multiple stoppers can be provided based on the number and corresponding positions of the drive rods 35. The second stopper 337 is an annular protrusion at the end of the drive sleeve 33, simplifying the structure.

[0042] It should be noted that the fine-tuning member 34 moves between the first stopper 331 and the second stopper 337 , and the movable arm 12 driven thereby is formed to a height smaller than the depth of the ball 122 that can penetrate into the limiting groove 121 .

[0043] Furthermore, a countersunk hole 332 is provided on the driving sleeve 33 , the first stopper 331 is slidably connected in the countersunk hole 332 , and a second elastic member 333 is provided between the bottom of the countersunk hole 332 and the first stopper 331 to achieve the extension and retraction of the first stopper 331 .

[0044] Furthermore, a through hole 334 is provided at the bottom of the counterbore 332, adjacent to the central axis of the drive sleeve 33. Through hole 334 is parallel to the central axis of the drive sleeve 33. A connecting hole is provided between the bottom of the counterbore 332 and through hole 334. A pull rope 335 is connected to the bottom of the first stopper 331. The pull rope 335 passes through the connecting hole, enters through hole 334, and exits through the end of through hole 334, where it is connected to a pull ring 336. Therefore, when the pull rope 335 is tightened by the pull ring 336, the pull rope 335 pulls the first stopper 331 into the counterbore 332. After the external force on the pull ring 336 is removed, the first stopper 331 extends outward due to the rebound action of the second elastic member 333. Thus, by connecting an extension rope to the pull ring 336 and extending it outside the welding pipe, the extension and retraction of the first stopper 331 can be remotely controlled. Furthermore, after the first stopper 331 contracts, the first elastic member 123 pushes the movable arm 12 to contract under the action of the rebound force, and the ball 122 is exposed from the limiting groove 121 and pressed against the pipe wall.

[0045] Furthermore, a guide roller is provided in the through hole 334 at a position aligned with the countersunk hole 332. The pull rope 335 extends from the countersunk hole 332 to the through hole 334 and then passes around the guide roller, thereby realizing the turning of the pull rope 335 and making it easier to pull the rope 335.

[0046] Furthermore, the drive device 3 includes at least two limiting rods 32. The limiting rods 32 are perpendicularly connected to the central support ring 2 and parallel to the support shaft 31. The limiting rods 32 pass through the drive sleeve 33 to achieve a sliding connection. Therefore, when the support shaft 31 rotates, the limiting rods 32 prevent the drive sleeve 33 from rotating with the support shaft 31, allowing the drive sleeve 33 to move along the support shaft 31.

[0047] Furthermore, the airbag sealing assembly 4 includes a sealing disk 41 and an annular airbag 42. The annular airbag 42 is sealed to the outer edge of the sealing disk 41 and is provided with an air inlet 43. The two annular airbags 42 are connected by a connecting pipe 5, and a pressure valve 6 is provided on the connecting pipe 5. Based on this, air can be inflated through one of the air inlets 43 to inflate both annular airbags 42. When the pressure reaches a certain value, the pressure valve 6 opens, inflating the space between the two airbag sealing assemblies 4 to protect the weld.

[0048] In order to facilitate the removal of the airbag sealing assembly 4 out of the pipeline, a threaded sleeve 46 is set at the center position of one of the sealing disks 41, which is threadedly connected to the support shaft 31, and a non-threaded sleeve 44 with a smooth inner wall is set at the center position of the other sealing disk 41, which can be loosely sleeved on the support shaft 31. With such an arrangement, when the windage device needs to be removed, the annular airbag 42 is deflated and the support frame is pulled out by the extension rope, wherein the support frame connected by the threaded sleeve 46 directly pulls out the airbag sealing assembly 4, and the non-threaded sleeve 44 is detached from the support frame when the other support frame is pulled out.

[0049] Furthermore, the two sealing disks 41 are connected by a telescopic rod 7. When the support frame is pulled out, the two deflated airbag sealing assemblies 4 will not contact the inner wall of the pipe under the support of the telescopic rod 7, thereby avoiding wear; and after the two support frames and the two airbag sealing assemblies 4 are installed, when the pipes to be welded are aligned, the telescopic rod 7 can conveniently adjust the distance between the two airbag sealing assemblies 4 without affecting use.

[0050] When using the argon-filled sealing device for welding in this embodiment, the support frame is placed in two pipes to be welded, the support shaft 31 is rotated, the drive sleeve 33 moves, and the movable arm 12 is extended through the drive rod 35. The end of the movable arm 12 is pressed against the inner wall of the pipe in a surface contact manner, increasing the friction surface and improving the support stability. An extension rope is connected to the pull ring 336 and extended out of the pipe where the extension rope is located, so as to pull out the support frame after welding is completed. The two airbag sealing assemblies 4 are connected to the two support frames respectively, and then inflated to achieve sealing, and welding can be carried out; and after welding is completed, the annular airbag 42 is deflated. By pulling the extension rope, the first stopper 331 is remotely controlled to retract, and under the rebound action of the first elastic member 123, the movable arm 12 is pushed, and then the fine-tuning member 34 is pushed to move toward the second stopper 337. At this time, the ball 122 supports the inner wall of the pipe. The ball 122 can roll to reduce the friction between the pipe wall, making it easier to pull out the support frame. During the entire pulling-out process, the support frame is supported on the inner wall of the pipe, and there will be no problems of skewing or jamming, making it smoother to pull out.

[0051] It should be noted that this embodiment is suitable for scenarios where the ends of the pipes at both ends that need to be welded can be conveniently extended with extension ropes to facilitate pulling out the two support frames from two directions respectively.

[0052] Specific implementation method 2: Figure 1-5As shown, an argon-filled sealing device for welding is different from the specific embodiment one in that the pull rope 335 is split into two, and after entering the through hole 334, it extends from both ends of the through hole 334 respectively, and a connecting ear 45 is provided on the sealing disk 41 with a non-threaded sleeve 44. When in use, the connecting ear 45 is connected to the pull ring 336 of the support frame on that side, and the pull ring 336 of the other support frame is connected to the extension rope and extends out of the pipeline. When pulling out the sealing device, the support frame on that side is pulled by the extension rope, and the support frame drives the airbag sealing assembly 4 to move, and the airbag sealing assembly 4 is connected to the pull ring 336 on the other support frame through the connecting ear 45 to pull out the other support frame. Other structures are not repeated here.

[0053] It should be noted that this embodiment is applicable to pipes that need to be welded, where the other end of one pipe is not convenient for extending the extension rope of the support frame, and the two support frames are simultaneously pulled out from the same side through an extension rope.

[0054] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the scope of protection of the present invention.

Claims

1. An argon-filled plugging device for welding, characterized by: The device comprises two support frames and air bag sealing components detachably connected to the two support frames for sealing the pipeline; The support frame includes a central support member, at least three retractable support arms, and a driving device for driving the support arms to retract; The support arms are evenly arranged along the circumference of the central support member; The support arm includes a fixed arm and a movable arm slidably connected to the fixed arm, and a ball supported by a first elastic member is provided in a limiting groove at the end of the movable arm; The driving device includes a support shaft rotatably connected to the central support member, a driving sleeve threadedly connected to the support shaft, a fine-tuning member slidably connected to the driving sleeve, and a driving rod, wherein both ends of the driving rod are respectively hinged to the movable arm and the fine-tuning member; The sliding path of the fine-tuning member is parallel to the moving path of the driving sleeve. A retractable first stopper and a fixed second stopper are provided on the driving sleeve along the sliding path of the fine-tuning member. The first stopper extends to stop the fine-tuning member and retracts to release the fine-tuning member. The first stopper is located on a side of the second stopper close to the support arm. The first stopper is remotely controlled by a pull cord; The first stopper is slidably connected to a countersunk hole provided on the driving sleeve, and a second elastic member is provided at the bottom of the countersunk hole to support the first stopper, thereby realizing the extension and retraction of the first stopper; The airbag blocking assembly includes a blocking disk and an annular airbag. The annular airbag is sealed and connected to the outer edge of the blocking disk. An air inlet is provided on the annular airbag. The two annular airbags are connected by a connecting pipe, and a pressure valve is provided on the connecting pipe. A threaded sleeve is provided at the center of one of the blocking discs and is threadedly connected to the support shaft. A non-threaded sleeve with a flat inner wall is provided at the center of the other blocking disc and can be loosely sleeved on the support shaft. The two occluding discs are connected by a telescopic rod; Connect the extension cord to the pull ring and extend the extension cord out of the pipe where it is located; A through hole parallel to the central axis of the drive sleeve is provided near the bottom of the countersunk hole, a connecting hole is provided between the bottom of the countersunk hole and the through hole, a pull rope is connected to the bottom of the first stopper, and the other end of the pull rope passes through the through hole, so that the first stopper can be remotely driven by the pull rope.

2. The argon-filling plugging device for welding according to claim 1, characterized in that: The drawstring is split into two and passes through the two ends of the through hole respectively.

3. The argon-filling plugging device for welding according to claim 2, characterized in that: A guide roller is provided in the through hole. The pull rope extends from the countersunk hole to the through hole and then passes around the guide roller to realize the turning of the pull rope.

4. The argon-filling plugging device for welding according to claim 3, characterized in that: The fine-tuning member adopts a fine-tuning sleeve, and the fine-tuning sleeve is sleeved on the driving sleeve to drive multiple driving rods at the same time.

5. The argon-filling plugging device for welding according to claim 4, characterized in that: The driving device further comprises at least two limiting rods connected to the central support member, wherein the limiting rods are parallel to the support shaft; the limiting rods pass through the driving sleeve to achieve a sliding connection.

6. The argon-filling plugging device for welding according to claim 1, characterized in that: The airbag sealing assembly with the non-threaded sleeve is provided with a connecting ear for connecting with a corresponding drawstring.

7. A plugging method using the welding argon plugging device according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: (1) Place the support frame in two pipes to be welded, rotate the support shaft, move the drive sleeve and extend the movable arm through the drive rod. The end of the movable arm is pressed against the inner wall of the pipe in a surface contact manner to increase the friction surface and improve the support stability. (2) Connect an extension cord to the pull ring and extend the extension cord out of the pipe to pull out the support frame after welding is completed; (3) Connect the two airbag sealing components to the two support frames respectively, inflate them to achieve sealing, and then weld them; (4) After the welding is completed, the annular airbag is deflated, and the first stopper is remotely controlled to retract by pulling the extension cord. Under the rebound action of the first elastic member, the movable arm is pushed, and then the fine-tuning member is pushed to move toward the second stopper; (5) At this time, the balls support the inner wall of the pipe. The balls can roll to reduce the friction between the balls and the pipe wall, making it easier to pull out the support frame. During the entire pulling process, the support frame is supported on the inner wall of the pipe, and there will be no problems of skewing or jamming, making it smoother to pull out.

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