A method for manufacturing a welding air chamber

Abstract

The invention relates to the field of welding air chambers and discloses a method for manufacturing a welding air chamber, wherein the welding air chamber is located at a welding port of a pipeline, and the manufacturing method comprises: making a rubber ball and a water-soluble paper ball; firstly putting the rubber ball into the pipeline from the welding port, and then putting the water-soluble paper ball into the pipeline; checking whether the water-soluble paper ball moves under a positive pressure state; if the water-soluble paper ball does not move, aligning the pipeline and filling argon gas into the welding port; after the air in the welding air chamber is emptied, welding is performed, thereby effectively improving the weld pass rate of the two pipelines to be butt-welded together with a large positive pressure from both sides to the pipe ports of the welding position.

Description

Technical Field

[0001] The invention relates to the technical field of welding air chambers, and in particular to a method for manufacturing a welding air chamber. Background Art

[0002] During the pipeline welding construction process of thermal power plants, especially high-alloy pipelines, in order to reduce the high-temperature oxidation of the molten metal at the root of the weld during the welding construction process, an air chamber is usually made before welding. After the pipeline is connected, the reserved gap in the connection is sealed with tape, and two holes are retained, namely the exhaust air hole and the argon delivery hole. Before formal welding, argon gas is passed into the air chamber to exhaust the air. In the process of making the air chamber, water-soluble paper balls are usually used to block the pipeline, but there are inevitably gaps between the water-soluble paper and the inner wall of the pipeline, and inside the water-soluble paper balls, and gas can still pass through the water-soluble paper balls; after the pipeline is welded, the water-soluble paper balls cannot be removed in an effective way. Therefore, in order to prevent the water-soluble paper balls from being easily unblocked during the process of passing water or steam through the pipeline and clogging the pipeline, the water-soluble paper balls cannot be densely blocked, which further causes the gas to easily pass through the water-soluble paper balls.

[0003] At the same time, in order to ensure the quality of welding, the air pressure in the air chamber cannot be too high and the gas flow cannot be too fast. The gas in the air chamber must be kept stable to prevent quality defects such as dense pores, concave roots and incomplete welding in the weld.

[0004] During the pipeline welding construction process, for some reason, there are two pipes that need to be butt-welded together, and a large positive pressure is emitted from both sides to the pipe opening of the welding position. According to the usual air chamber production method, argon gas introduction pressure and flow rate, the air with positive pressure on both sides will still enter the air chamber, and in the welding process, the air is easy to escape at the welding point, resulting in an increase in defects such as welding porosity, concave, and incomplete penetration. The quality cannot be guaranteed, and in severe cases, welding construction cannot even be carried out.

[0005] Therefore, how to effectively improve the weld pass rate of the two pipes that need to be butt-welded together with a large positive pressure from both sides to the pipe opening of the welding position is a problem that needs to be solved. Summary of the invention

[0006] The purpose of the present invention is to solve the above-mentioned problem of effectively improving the weld qualification rate of the two pipes to be butt-welded together with a large positive pressure from both sides to the pipe mouth of the welding position, and provide a method for manufacturing a welding air chamber, including first manufacturing a rubber ball and placing a water-soluble paper ball in the pipe, then checking whether the water-soluble paper ball moves, and after confirmation, aligning the pipe and flushing argon gas to perform welding.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] In some embodiments of the present application, a method for manufacturing a welding chamber, wherein the welding chamber is located at a welding port of a pipe, comprises: making a rubber ball and a water-soluble paper ball; first placing the rubber ball into the pipe, and then placing the water-soluble paper ball into the pipe; checking whether the water-soluble paper ball moves under a positive pressure state; if the water-soluble paper ball does not move, aligning the pipe and filling the welding port with argon gas; and performing welding after the air in the welding chamber is emptied.

[0009] In some embodiments of the present application, checking whether the water-soluble paper ball will move under a positive pressure state further includes: checking whether both sides of the rubber ball and the water-soluble paper ball are leaking, and if not, aligning the pipes.

[0010] In some embodiments of the present application, the rubber ball and the water-soluble paper ball are checked for air leakage, specifically, a burning flame is placed on one side of the welding port of the pipe, and positive pressure gas is blown from the other side of the pipe. If the flame does not move or is not blown out, it is determined that there is no air leakage.

[0011] In some embodiments of the present application, before placing the rubber ball in the pipe, the process further includes: grinding the welding joint and the inner wall of the pipe with a grinder to clean the burrs on the surface of the pipe.

[0012] In some embodiments of the present application, the pipeline is aligned and argon is filled into the welding port. Specifically, after the pipeline is aligned, the welding port of the pipeline is sealed with tape, and an argon hole and an air hole are reserved at the welding port. The argon hole and the air hole are arranged opposite to each other in the radial direction of the pipeline. Argon enters the pipeline through the argon hole, and the air in the pipeline is discharged from the air hole.

[0013] In some embodiments of the present application, after welding is completed, an oxyacetylene flame is used to heat the outer wall of the pipe at the location of the rubber ball to cause the rubber ball to burst.

[0014] In some embodiments of the present application, the inner diameter of the rubber ball is 0.5 mm-1 mm; the inner diameter of the water-soluble paper ball is 2 mm-3 mm.

[0015] In some embodiments of the present application, the argon hole is at the bottom of the pipe, and the air hole is at the top of the pipe; the diameters of the argon hole and the air hole are 5 mm.

[0016] In some embodiments of the present application, the manufacturing method as described in claim 8 is characterized in that the flow rate of the argon gas is 8-12 L / min, and a flame is placed at the air hole, and the flame is extinguished after 1min-5min, and the air in the pipeline is discharged.

[0017] The beneficial effects of the present invention are:

[0018] 1. The method for making a welding air chamber in the present invention effectively solves the problem of unclean air discharge and large gas flow in the air chamber by placing a small rubber balloon and a small water-soluble paper ball inside the pipeline, and basically does not increase the construction cost.

[0019] 2. The gas chamber manufacturing method ensures that after the argon gas is introduced, the gas chamber is filled with argon gas, which effectively prevents the oxidation problem of the high-temperature molten metal filled during the welding process and improves the welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the welding air chamber in the present invention;

[0021] Figure 2 A flow chart of a method for manufacturing a welding chamber according to an embodiment of the present invention;

[0022] Figure 3 The present invention is a flowchart of a method for manufacturing a welding chamber according to another embodiment of the present invention.

[0023] Markings in the figure: 100, pipe; 200, rubber ball; 300, water-soluble paper ball; 400, argon hole; 500, air hole. DETAILED DESCRIPTION

[0024] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0025] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0026] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0027] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0028] In some embodiments of the present application, as shown in the figure, a method for manufacturing a welding air chamber is proposed, which forms an airless air chamber at the welding position of two pipes, so that after the pipes are welded, the weld at the welding joint has less porosity or incomplete penetration.

[0029] In some embodiments of the present application, S101, first make rubber balls and water-soluble paper balls. In some specific embodiments, the inner diameter of the rubber ball is 0.5mm-1mm smaller than the inner diameter of the pipe, and the rubber ball is firmly tied to prevent air leakage of the rubber ball. The inner diameter of the water-soluble paper ball is 2mm-3mm larger than the inner diameter of the pipe.

[0030] In this embodiment, the rubber ball is elastic and can adapt to the inner diameter and shape of the pipe, which is sufficient to close the pipe.

[0031] In some embodiments of the present application, it is necessary to first process the pipeline, grind the welding joints and inner walls of the pipeline with a grinder, and clean the burrs on the surface of the pipeline until the metallic luster is exposed. Then, use 80, 120, 180, and 280 grit sandpaper to grind in sequence to ensure that the burrs on the pipeline bevel and inner wall are cleaned.

[0032] In some embodiments of the present application, S102, a rubber ball is first placed into the pipe from the welding port, and then a water-soluble paper ball is placed into the pipe, so that the positive pressure air blown from the other end of the pipe will be first blocked by the rubber ball, and the water-soluble paper ball is on the other side of the rubber ball. Under ideal conditions, the rubber ball can isolate the positive pressure air and prevent the positive pressure air from blowing to the water-soluble paper ball, thereby causing leakage in the welding air chamber.

[0033] In some embodiments of the present application, S103 checks whether the water-soluble paper ball will move under positive pressure. This is done by checking whether the water-soluble paper ball will move when positive pressure air blows in the presence of the rubber ball. This is actually a rough check of whether the rubber ball is properly installed.

[0034] In addition, after checking whether the water-soluble paper ball will move under positive pressure, when it is determined that the water-soluble paper ball does not move, check whether there are leaks on both sides of the rubber ball and the water-soluble paper ball. If there are no leaks, it means that the rubber ball and the water-soluble paper ball are installed in place and proceed to the next step.

[0035] The specific method for detecting gas leaks is: a burning flame is placed on one side of the welding joint of the pipeline, and positive pressure gas is blown from the other side of the pipeline. If the flame does not move or is not blown out, it is determined that there is no gas leak.

[0036] In some embodiments of the application, S104, after checking to make sure that the water-soluble paper ball does not move and the pipe does not leak, the pipe is aligned and argon is filled into the welding port. The specific filling method is that after the pipe is aligned, the welding port of the pipe is sealed with tape, and argon holes and air holes are reserved at the welding port. The argon holes and air holes are arranged opposite to each other in the radial direction of the pipe. Argon enters the pipe through the argon holes, and the air in the pipe is discharged by the air hole.

[0037] A closed space is formed by two aligned pipes and rubber balls and water-soluble paper balls inside the two pipes, which is the welding air chamber.

[0038] In some specific embodiments, S105, the argon hole is at the bottom of the pipe, the air hole is at the top of the pipe, the diameter of the argon hole and the air hole is 5mm, the flow rate of the introduced argon is 8-12L / min, and the flame is placed at the air hole. In the process of argon gas continuously entering the welding chamber, the air in the welding chamber is discharged from the air hole. After 1-5 minutes, the flame at the air hole goes out, indicating that the air in the welding chamber has been exhausted. At this time, there is only argon gas in the welding machine chamber, and the welding joints of the two pipes are welded.

[0039] In addition, after the welding is completed, the outer wall of the pipe at the location of the rubber ball is heated with an oxyacetylene flame to cause the rubber ball to burst. After the rubber ball bursts, the water-soluble paper ball can be directly taken out without affecting the use of the pipe.

[0040] In some embodiments of the application, the specific steps of a method for manufacturing a welding air chamber are:

[0041] S201, prepare rubber balls and water-soluble paper balls, and execute step S202;

[0042] S202, polishing the pipe with a polishing machine until the pipe has a metallic luster and no burrs, and then executing step S203;

[0043] S203, putting the rubber ball into the pipe from the welding port, and then putting the water-soluble paper ball into the pipe, and executing step S204;

[0044] S204, checking whether the water-soluble paper ball moves under the positive pressure state, if the water-soluble paper ball does not move, executing step S205, if the water-soluble paper ball moves, executing S103;

[0045] S205, check whether there is any leakage on both sides of the rubber ball and the water-soluble paper ball, that is, place a burning flame on one side of the welding port of the pipeline, and the positive pressure gas is transmitted from the other side of the pipeline. If the flame does not move or is not blown out, it is determined that there is no leakage, and step S206 is executed. If the flame moves or is blown out, it is a leakage, and step S203 is executed;

[0046] S206, align the pipelines, seal the welding ports of the pipelines with tape, and reserve argon holes and air holes at the welding ports, and execute step S207;

[0047] S207, fill argon gas into the pipeline through the argon hole, place the flame at the air hole until the flame is extinguished, and execute step S208;

[0048] S208, welding the welding joint of the pipeline, and completely sealing the welding joint to complete the welding, and executing step S209;

[0049] S209, using an oxyacetylene flame to heat the outer wall of the pipe at the location of the rubber ball until the rubber ball breaks.

[0050] Those skilled in the art can understand that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a welding air chamber, wherein the welding air chamber is located at a welding port of a pipeline, characterized in that: include: Making rubber balls and water-soluble paper balls, wherein the inner diameter of the rubber balls is 0.5 mm to 1 mm smaller than the inner diameter of the pipe, and the inner diameter of the water-soluble paper balls is 2 mm to 3 mm larger than the inner diameter of the pipe; First, put the rubber ball into the pipe from the welding port, and then put the water-soluble paper ball into the pipe; Check whether the water-soluble paper ball moves under positive pressure; If the water-soluble paper ball does not move, align the pipes and fill the welding port with argon; After the air in the welding air chamber is emptied, welding is performed.

2. The manufacturing method according to claim 1, characterized in that Check whether the water-soluble paper ball moves under positive pressure, and then include: Check whether both sides of the rubber ball and the water-soluble paper ball are leaking. If not, align the pipes.

3. The manufacturing method according to claim 2, characterized in that: Check whether the rubber ball and the water-soluble paper ball are leaking, specifically: A burning flame is placed on one side of the welding port of the pipeline, and positive pressure gas is blown from the other side of the pipeline. If the flame does not move or is not blown out, it is determined that there is no gas leakage.

4. The manufacturing method according to claim 1, characterized in that: Before placing the rubber ball in the pipe, the method further comprises: The welding joint and the inner wall of the pipeline are polished with a grinder to remove the burrs on the surface of the pipeline.

5. The manufacturing method according to claim 1, characterized in that: Align the pipes and fill the weld with argon gas as follows: After the pipeline is aligned, the welding joint of the pipeline is sealed with tape, and an argon hole and an air hole are reserved at the welding joint. The argon hole and the air hole are arranged opposite to each other in the radial direction of the pipeline. Argon enters the pipeline through the argon hole, and the air in the pipeline is discharged through the air hole.

6. The manufacturing method according to claim 1, characterized in that: After welding is completed, an oxyacetylene flame is used to heat the outer wall of the pipe at the location of the rubber ball to cause the rubber ball to burst.

7. The manufacturing method according to claim 5, characterized in that: The argon hole is at the bottom of the pipe, and the air hole is at the top of the pipe; the diameters of the argon hole and the air hole are 5 mm.

8. The manufacturing method according to claim 7, characterized in that: The flow rate of the argon gas is 8-12 L / min, and a flame is placed at the air hole. The flame goes out after 1-5 minutes, and the air in the pipeline is discharged.

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