Pipeline plugging assembly and pipeline plugging welding method

Abstract

The invention provides a pipeline plugging assembly and a pipeline plugging welding method.The pipeline plugging assembly comprises a fixed plugging part and a sealing plug which are located in a to-be-welded pipeline, the two opposite sides of a to-be-welded position are filled with the fixed plugging part and the sealing plug in a sealed mode respectively, or one side of the to-be-welded position is filled with the fixed plugging part in a sealed mode; the fixed plugging part is of a block-shaped structure or a sheet-shaped structure made of a surfactant; the sealing plug is provided with a through hole allowing the protective gas pipe to penetrate through, the protective gas pipe is used for filling protective gas into the sealing area where the position to be welded is located, and the sealing plug can move in the pipeline to be welded under pulling of the protective gas pipe. The fixed plugging part does not generate carbides, so that the hidden danger of pipeline plugging is solved; the sealing performance of a sealing area where the formed position to be welded is located is good, and a root welding seam can be fully protected; part of grease in the pipeline can be removed, an alkaline environment is formed in the pipeline to protect the boiler, and the welding efficiency of the pipeline is improved.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline welding, and in particular to a pipeline plugging component and a pipeline plugging welding method. Background Art

[0002] In the prior art, some pipes made of certain materials need to prevent oxidation of the root weld during welding, and argon needs to be filled inside the pipe for protection before welding. For example, high-alloy pipes refer to heat-resistant steels with a chromium content greater than 3% or a total alloy content greater than 5% according to the specification requirements, generally including 9%Cr-12%Cr martensitic heat-resistant steel, austenitic stainless steel, and nickel-based alloys.

[0003] The existing methods for sealing the welding area of ​​small-diameter pipelines include: using knife paper or water-soluble paper to make a ball and insert it into the pipe; or using water-soluble paper to roll into a cone and insert it into the pipe; or using water-soluble paper to stick the water-soluble paper into the pipe with water-solid.

[0004] The applicant has found that the prior art has at least the following technical problems:

[0005] On the one hand, the pipeline plugging method in the prior art is easy to block the pipeline. The reasons are: (1) Although knife paper or water-soluble paper is more soluble in water than other materials, if the knife paper or water-soluble paper is too close to the welding area, it will be affected by the heat of the welding area and the inert protective gas, and the knife paper, water-soluble paper and hydrosol will not burn, but form carbides; (2) The pipelines within the boiler range that need to be filled with protective gas for protection are concentrated on the boiler heating surface, and due to the improvement of various parameters such as boiler thermal efficiency, most boiler heating surfaces are designed as serpentine pipes or π-shaped pipes, which are prone to siltation; and the number of pipelines is increased, and the pipeline diameter is reduced. (3) The medium in the heating surface pipeline is high-temperature and high-pressure steam, which has little erosion effect on the formed carbides, and cannot burn such carbides, and will also cause carbides. (4) Water-soluble paper will form hard blocks when it is dry-burned at high temperature without dissolving in water. The formed substance is not easy to dissolve in water. Especially when a large amount of water-soluble paper gathers in a certain place or forms a mass, the above phenomenon will become more serious.

[0006] The above reasons can easily lead to carbides accumulating inside the pipeline, and they cannot be completely blown out by boiler water pressure, flushing and blowing. In addition, the steam generated by blowing or operation will also blow the carbides together, eventually causing pipeline blockage. If the pipeline is blocked for a long time, the pipeline here will overheat. Long-term high temperature will cause the pipeline to burst, resulting in "non-stop" of the unit and affecting the reliability of the unit.

[0007] On the other hand, the existing pipe plugging methods do not provide good protection for welds. The reasons are: (1) Compared with the other two plugging methods, paper ball plugging has more gaps with the inside of the pipe; (2) water-soluble paper or knife paper is made of plant fibers and has larger pores; (3) the carbide formed by knife paper or water-soluble paper when heated is relatively loose.

[0008] The above situation will cause the air chamber generated by the protective gas to leak, which will not provide good protection for the root weld, and then cause the root weld to oxidize. The weld will be damaged during the long-term operation of high-temperature and high-pressure steam, and the service life of the weld will be shortened, which is more likely to cause boiler tube burst. Summary of the invention

[0009] The purpose of the present invention is to provide a pipeline plugging assembly and a pipeline plugging welding method to solve the technical problem that the prior art uses knife paper or water-soluble paper balls to plug the welding area into the pipe, which is easy to block the pipe and provide poor protection for the weld. The preferred technical solutions among the many technical solutions provided by the present invention can produce many technical effects as described below.

[0010] To achieve the above object, the present invention provides the following technical solutions:

[0011] The pipeline plugging assembly provided by the present invention comprises a fixed plugging portion and a sealing plug located in the pipeline to be welded, wherein:

[0012] The fixed sealing part and the sealing plug are respectively sealed and filled at two opposite sides of the position to be welded, or the fixed sealing part is sealed and filled at one side of the position to be welded;

[0013] The fixed sealing part is a block structure or a sheet structure made of a surfactant;

[0014] The sealing plug is provided with a through hole for a protective gas pipe to pass through. The protective gas pipe is used to fill the sealing area where the welding position is located with protective gas, and the sealing plug can move in the pipe to be welded under the pull of the protective gas pipe.

[0015] Preferably, the fixed sealing part is a truncated cone structure, the upper bottom diameter of the fixed sealing part is smaller than the inner diameter of the pipe to be welded, the lower bottom diameter of the fixed sealing part is larger than the inner diameter of the pipe to be welded, and the lower bottom of the fixed sealing part faces the welding position.

[0016] Preferably, the thickness of the fixed sealing portion is 5-10 mm.

[0017] Preferably, the sealing plug is made of polymer material.

[0018] Preferably, the protective gas pipe is an inert gas pipe, and the gas outlet of the inert gas pipe faces the position to be welded.

[0019] The present invention also provides a pipeline plugging welding method, using the above pipeline plugging assembly, the plugging welding method comprises:

[0020] The fixed sealing part and the sealing plug are respectively sealed and filled on two opposite sides of the position to be welded;

[0021] Pass the protective gas pipe through the through hole to fill the sealing area where the welding position is located with protective gas;

[0022] After the inflation is completed, the first welding position is welded.

[0023] Preferably, the plugging welding method further comprises: before filling the sealing area where the welding position is located with a protective gas, it also comprises:

[0024] A polymer sealing strip is used to wrap and seal the position to be welded, and the polymer sealing strip can melt during welding.

[0025] Preferably, the plugging welding method further comprises:

[0026] After welding the first position to be welded, the protective gas pipe is pulled, so that the sealing plug moves in the pipe to be welded under the pulling of the protective gas pipe until the sealing plug moves to one side of the second position to be welded;

[0027] Insert the new fixed sealing part into the other side of the second position to be welded;

[0028] Use a new polymer sealing strip to wrap and seal the second welding position;

[0029] Filling the sealing area where the second welding position is located with protective gas;

[0030] Weld the second position to be welded.

[0031] Preferably, the above operation is repeated until only the last position to be welded where a sealing plug cannot be used remains on the entire pipeline.

[0032] Preferably, when welding is performed on the last position to be welded of the pipeline, the fixed sealing portion is sealed and filled beside the last position to be welded, so that the last position to be welded is placed in a protective atmosphere.

[0033] Compared with the prior art, the pipeline plugging assembly and pipeline plugging welding method provided by the present invention have the following beneficial effects: the fixed plugging part made of surfactant will not produce carbide, thereby solving the hidden danger of pipeline blockage; the sealing area where the position to be welded is formed has good sealing performance and can fully protect the root weld; part of the grease in the pipeline can be removed to form an alkaline environment in the pipeline to protect the boiler; and the sealing plug cooperates with the protective air pipe and can be located and moved in the pipeline to be welded, thereby realizing mobile protection of different positions to be welded and improving the welding efficiency of the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 It is a schematic diagram of the matching structure of the pipeline plugging component and the pipeline to be welded;

[0036] Figure 2 It is a schematic diagram of the moving structure of the protective gas pipe in the pipeline to be welded.

[0037] In the figure, 1, fixed sealing part; 2, sealing plug; 21, through hole; 3, protective air pipe; 4, polymer sealing strip; 100, pipeline; 101, welding seam. DETAILED DESCRIPTION

[0038] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0039] In the description of the present invention, it should be understood that the terms "center", "length", "width", "height", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "side" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0040] The embodiments of the present invention provide a pipeline plugging assembly and a pipeline plugging welding method, which will not produce carbides in the pipeline, have better sealing performance, can achieve mobile protection of different welding positions, and improve the welding efficiency of the pipeline.

[0041] Combine the following Figure 1 and Figure 2 The technical solution provided by the present invention is described in more detail.

[0042] Embodiment 1:

[0043] See also Figure 1 and Figure 2 As shown, the present invention provides a pipe sealing assembly, comprising a fixed sealing part 1 and a sealing plug 2 located in the pipe to be welded 100, wherein: the fixed sealing part 1 and the sealing plug 2 are respectively sealed and filled on opposite sides of the position to be welded, or the fixed sealing part 1 is sealed and filled on one side of the position to be welded; the fixed sealing part 1 is a block structure or a sheet structure made of a surfactant; the sealing plug 2 is provided with a through hole 21 for a protective gas pipe 3 to pass through, the protective gas pipe 3 is used to fill the sealing area where the position to be welded is located with a protective gas, and the sealing plug 2 can move in the pipe to be welded 100 under the pull of the protective gas pipe 3, and move to the side of the remaining positions to be welded.

[0044] Among them, for the last weld 101 of the pipeline 100, the fixed sealing part 1 is sealed and filled on one side of the position to be welded, and for the remaining welds 101 of the pipeline 100, the fixed sealing part 1 and the sealing plug 2 are sealed and filled on opposite sides of the position to be welded respectively.

[0045] The pipe 100 to be welded includes multiple pipe sections with welds 101. It should be understood that the pipe sections are interconnected, and the sealing plug 2 can be moved in the multiple pipe sections under the pull of the protective gas pipe 3. However, there are welds 101 between the pipe sections, and the purpose of this embodiment is to weld the welds 101 between the pipe sections using a welding device (that is, the position to be welded is the weld 101).

[0046] In order to facilitate pulling the protective air tube 3, a protruding structure can be fixed on the protective air tube 3, so that the user can hold it by hand or pull it through an external power device.

[0047] The pipeline plugging component of this embodiment has the following beneficial effects: the fixed plugging part 1 made of surfactant does not produce carbide compared to the knife paper or water-soluble paper in the prior art, thereby solving the hidden danger of clogging of the pipeline 100.

[0048] In the prior art, the knife paper or water-soluble paper is inserted into the pipe 100 in the form of a paper ball. Compared with the other two plugging methods, the paper ball plugging has more gaps inside the pipe 100; the water-soluble paper or knife paper is made of plant fibers and has larger pores; the carbide formed by the knife paper or water-soluble paper when heated is relatively loose. In this embodiment, the fixed plugging part 1 made of a surfactant is inserted into the pipe 100, with less gaps, and the sealing area formed where the welding position is located has good sealing performance, which can fully protect the root weld 101;

[0049] On the other hand, the fixed sealing part 1 made of surfactant can remove part of the grease in the pipeline 100 and form an alkaline environmental protection boiler in the pipeline 100.

[0050] The sealing plug 2 cooperates with the protective gas pipe 3 and can be moved inside the pipeline 100 to be welded, thereby realizing mobile protection of different positions to be welded and improving the welding efficiency of the pipeline 100.

[0051] The following description will be made by taking the weld 101 as the position to be welded.

[0052] As an alternative embodiment, see Figure 1 As shown, the fixed sealing part 1 is a truncated cone-shaped structure, the upper base diameter of the fixed sealing part 1 is smaller than (slightly smaller than) the inner diameter of the pipe 100 to be welded, the lower base diameter of the fixed sealing part 1 is larger than (slightly larger than) the inner diameter of the pipe 100 to be welded, and the lower base of the fixed sealing part 1 faces the position to be welded.

[0053] The fixed sealing part 1 of the truncated cone structure is convenient for being inserted into the pipe 100, and the bottom of the fixed sealing part 1 faces the position to be welded (weld 101). Figure 1 As shown, it is convenient to improve the sealing of the weld 101.

[0054] As an optional implementation, specifically, in this embodiment, the fixed sealing portion 1 has a sheet structure with a thickness of 5-10 mm, which is convenient for being inserted into the pipe 100 to seal and protect the weld 101 .

[0055] As an alternative embodiment, see Figure 1 As shown, the sealing plug 2 of this embodiment is made of polymer material.

[0056] The sealing plug 2 is made of elastic material and is squeezed and sealed in the pipeline 100 . When the protective air pipe 3 passes through the through hole 21 of the sealing plug 2 , one side of the weld 101 can be sealed.

[0057] See also Figure 1As shown, one side of the weld 101 is sealed by a fixed sealing portion 1, and the other side is sealed by a sealing plug 2 and a protective gas pipe 3 passing through the sealing plug. The weld 101 is located between the fixed sealing portion 1 and the sealing plug 2. When the weld 101 is inflated for protection, a polymer sealing strip 4 is used to wrap the weld 101. The polymer sealing strip 4 wraps the weld 101 360°. With this arrangement, the weld 101 can be in a sealed area to prevent leakage of the protective gas.

[0058] Specifically, the shielding gas pipe 3 is an inert gas pipe, the gas outlet of the inert gas pipe faces the position to be welded, and the shielding gas is an inert gas, such as argon, nitrogen, etc., to prevent oxidation of the root weld.

[0059] Embodiment 2:

[0060] See also Figure 1 and Figure 2 As shown, this embodiment provides a pipeline plugging welding method, using the above-mentioned pipeline plugging assembly, the plugging welding method includes: sealing and filling the fixed sealing part 1 and the sealing plug 2 on the opposite sides of the position to be welded respectively; passing the protective gas pipe 3 through the through hole 21, and filling the sealing area where the position to be welded is located with protective gas; after the inflation is completed, welding the first position to be welded.

[0061] Figure 2 The arrow direction in the figure is the moving direction of the protective air pipe 3. The two welds 101 framed in the figure are the first weld 101 (left side in the figure) and the last weld 101 (right side in the figure) of the pipeline 100.

[0062] The fixed sealing part 1 is a block or sheet structure made of a surfactant, such as soap flakes. The main component of soap is sodium stearate. The use of soap flakes can ensure the sealing of the air chamber; and the soap flakes are soluble in water and have a certain lubricity. In the heating surface of the boiler, even if the soap flakes are not taken out, after the boiler water pressure, pipe flushing and other processes, it can still ensure that the pipeline 100 is not blocked before the overall operation. In addition, excess grease in the pipe can be removed to ensure the alkaline environment inside the boiler.

[0063] As an optional implementation, the plugging welding method further includes: before filling the sealing area where the welding position is located with a protective gas, it also includes: using a polymer sealing strip 4 to wrap and seal the welding position, and the polymer sealing strip 4 can melt during welding.

[0064] The polymer sealing strip 4 wraps the weld 101 360°, so that the weld 101 can be in a sealed area to prevent leakage of the protective gas. The polymer sealing strip 4 can melt during welding and will not affect the welding work of the weld 101.

[0065] As an alternative embodiment, see Figure 1 and Figure 2 As shown, the plugging welding method also includes: after the welding of the first position to be welded is completed, the protective gas pipe 3 is pulled, so that the sealing plug 2 moves in the pipe 100 to be welded under the pulling of the protective gas pipe 3 until the sealing plug 2 moves to one side of the second position to be welded; a new fixed plugging part 1 is inserted on the other side of the second position to be welded; a new polymer sealing strip 4 is used to wrap and seal the second position to be welded; the sealing area where the second position to be welded is located is filled with protective gas; and the second position to be welded is welded. Repeat the above operations until only the last position to be welded that cannot be welded with the sealing plug 2 is left in the entire pipe 100.

[0066] In the above method, for each weld 101, a fixed plugging portion 1 is inserted into one side of the weld 101 between adjacent pipe sections. Figure 2 For the first weld 101 in the figure, the fixed sealing part 1 and the sealing plug 2 are respectively inserted into the upper side and the lower side of the first weld 101 (the upper side and the lower side only represent the position in the figure). Figure 2 For the last weld 101 in the pipeline 100, the fixed plugging part 1 is inserted into the upper side of the last weld 101 (the upper side only indicates the position in the figure). Except for the last weld 101 of the pipeline 100, the sealing plug 2 is filled in the other side of the weld 101, and the polymer sealing strip 4 is wrapped around the weld 101, so that the weld 101 is in the sealing area, and welding is performed under the protection of the protective gas.

[0067] Furthermore, by pulling the protective gas pipe 3, the sealing plug 2 can be synchronously moved. The protective gas pipe 3 can provide gas protection to different positions of the weld seams 101 without being pulled out, thereby improving the gas filling efficiency and thus improving the welding efficiency.

[0068] As an optional implementation, when welding is performed on the last position to be welded of the pipeline 100, the fixed sealing portion 1 is sealed and filled beside the last position to be welded, so that the last position to be welded is in a protective atmosphere.

[0069] For the last weld 101 of the pipeline 100, since the front side of the weld 101 is already in the atmosphere of protective gas and the interior of the pipeline 100 is filled with protective gas at this time, the fixed sealing part 1 is about to be inserted into the pipeline 100 before the last weld is aligned. Therefore, it is only necessary to use a gas needle to inflate from the weld position to meet the protection requirements, and the other side is sealed with the fixed sealing part 1, which greatly reduces the workload of filling the protective gas (argon or other inert gas).

[0070] In the description of this specification, specific features, structures or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0071] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0072] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A pipeline plugging assembly, characterized in that: It includes a fixed plugging portion and a sealing plug located in the pipe to be welded, wherein: The fixed sealing part and the sealing plug are respectively sealed and filled at two opposite sides of the position to be welded, or the fixed sealing part is sealed and filled at one side of the position to be welded; The fixed sealing part is a block structure or a sheet structure made of a surfactant; The sealing plug is provided with a through hole for a protective gas pipe to pass through. The protective gas pipe is used to fill the sealing area where the welding position is located with protective gas, and the sealing plug can move in the pipe to be welded under the pull of the protective gas pipe.

2. The pipeline plugging assembly according to claim 1, characterized in that: The fixed sealing part is a truncated cone structure, the upper bottom diameter of the fixed sealing part is smaller than the inner diameter of the pipe to be welded, the lower bottom diameter of the fixed sealing part is larger than the inner diameter of the pipe to be welded, and the lower bottom of the fixed sealing part faces the position to be welded.

3. The pipeline plugging assembly according to claim 1 or 2, characterized in that: The thickness of the fixed sealing part is 5-10 mm.

4. The pipeline plugging assembly according to claim 1, characterized in that: The sealing plug is made of polymer material.

5. The pipeline plugging assembly according to claim 1, characterized in that: The protective gas pipe is an inert gas pipe, and the gas outlet of the inert gas pipe faces the position to be welded.

6. A pipeline plugging welding method, characterized in that: Using the pipeline plugging assembly according to any one of claims 1 to 5, the plugging welding method comprises: The fixed sealing part and the sealing plug are respectively sealed and filled on two opposite sides of the position to be welded; Pass the protective gas pipe through the through hole to fill the sealing area where the welding position is located with protective gas; After the inflation is completed, the first welding position is welded.

7. The pipeline plugging welding method according to claim 6, characterized in that: The plugging welding method further comprises: before filling the sealing area where the welding position is located with a protective gas, the method further comprises: A polymer sealing strip is used to wrap and seal the position to be welded, and the polymer sealing strip can melt during welding.

8. The pipeline plugging welding method according to claim 6, characterized in that: The plugging welding method also includes: After welding the first position to be welded, the protective gas pipe is pulled, so that the sealing plug moves in the pipe to be welded under the pulling of the protective gas pipe until the sealing plug moves to one side of the second position to be welded; Insert the new fixed sealing part into the other side of the second position to be welded; Use a new polymer sealing strip to wrap and seal the second welding position; Filling the sealing area where the second welding position is located with protective gas; Weld the second position to be welded.

9. The pipeline plugging welding method according to claim 8, characterized in that: Repeat the above operation until only the last welding position that cannot be sealed with a sealing plug remains on the entire pipe.

10. The pipeline plugging welding method according to claim 6, characterized in that: When welding is performed on the last position to be welded of the pipeline, the fixed sealing portion is sealed and filled beside the last position to be welded, so that the last position to be welded is placed in a protective atmosphere.

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