Automatic argon arc welding backing welding argon filling protection welding tool

Abstract

The utility model discloses an automatic argon arc welding backing welding argon filling protection welding tool which comprises an air inflation groove fixedly buckled on the back face of a welded junction, the air inflation groove is arranged along the length of the welded junction, a blocking structure is arranged at the end of the air inflation groove, and an air inflation connector is arranged on the air inflation groove. The inflation groove is fixed through a U-shaped clamping plate and a wedge-shaped pin, the U-shaped clamping plate stretches across the inflation groove and is connected with the two pieces to be welded respectively, and the wedge-shaped pin is arranged on the back face of the inflation groove and inserted into a gap between the inflation groove and the U-shaped clamping plate. By the adoption of the structure that the inflation groove is fixedly buckled on the back face of the welded junction, before backing welding of the welded junction is started, the groove is filled with argon, deposited metal in the welding process is isolated from air through the argon, oxidation of the welded junction is avoided, the structure can be combined with a welded junction assembly tool to achieve fixation of the inflation groove, a U-shaped clamping plate can be omitted, the structure is simple, and cost is low. And meanwhile, the structure is only filled with argon in the groove, so that the use amount of the argon is small, and the cost can be saved.

Description

Technical Field

[0001] The utility model relates to a welding tooling, in particular to an automatic argon arc welding backing welding argon filling protection welding tooling. Background Technique

[0002] As a clean and pollution-free energy source, LNG (liquefied natural gas) has been widely used at home and abroad. There are more than 130 LNG receiving stations built (including under construction) globally. Since the first Shenzhen Dapeng LNG receiving station in China started in 2004, dozens of receiving stations have been built in China, and multiple LNG receiving station storage tanks are under construction for welding construction. The structural form of LNG cryogenic storage tanks is generally a self-supporting dome tank, which belongs to a fully enclosed storage tank and is usually composed of a prestressed concrete outer tank, a carbon steel outer tank lining, and a 9% Ni steel inner tank. The storage tank has a large volume. So far, it has developed from 160,000 m 3 to 200,000 m 3 、220,000 m 3 、270,000 m 3 . The thickness of the inner tank wall plate is the thickest at 38 mm and the thinnest at 10 mm. The welding workload of the storage tank will also be increasing. Taking a 160,000 m³ storage tank as an example, the diameter of the metal inner tank is 80 m, the height of the tank wall is 35.43 m, and the total welding length of the circumferential and longitudinal seams of the inner tank wall is 3,450 m. Therefore, the welding of 9% Ni steel for the inner tank is the most critical link in the construction of LNG storage tanks.

[0003] At present, for the commonly used welding methods of the inner tank of LNG storage tanks, submerged arc automatic welding is used for the circumferential seams, but manual shielded metal arc welding has been used for the longitudinal seams. The disadvantages of using manual shielded metal arc welding are as follows: 1) Due to manual operation, the welding efficiency is low and the labor intensity is high; 2) It is impossible to achieve single-sided welding with double-sided formation for backing welding with shielded metal arc welding. It is necessary to grind the root on the back with a grinding wheel. And because the wall plate is relatively thick, multi-layer and multi-pass welding is required. It is necessary to grind the welding slag between each pass, and the grinding workload is relatively large, and the noise and dust pollution are relatively serious; 3) For manual operation of shielded metal arc welding, the heat input is uneven, and for multi-pass welding, the total heat input is high, and the wall plate is prone to deformation, and the welding quality cannot be guaranteed. Therefore, the longitudinal seam automatic welding process technology is being developed in the LNG storage tank welding industry, and the development focuses on process technologies such as flux-cored wire arc welding and hot wire TIG welding. Since hot wire TIG welding has good welding quality, and there is no need for inter-pass grinding, which reduces dust and realizes green environmental protection. Therefore, hot wire TIG welding technology is the welding method that is focused on research and development and popularization and application. Since the welding consumables for welding 9% Ni steel are nickel-based welding consumables, it is necessary to carry out argon protection on the back to prevent the weld bead from oxidizing. However, the height of the LNG storage tank wall plate is relatively high, and it is difficult to carry out argon protection on the back. Therefore, it is necessary to design a welding tooling to facilitate argon filling protection for the backing weld bead on the back. Content of the Utility Model

[0004] The present utility model provides an automatic argon arc welding backing welding argon filling protection welding tooling to solve the technical problems existing in the known technology, which can facilitate the argon filling protection on the back of the backing weld bead.

[0005] The technical solution adopted by the present utility model to solve the technical problems existing in the known technology is: an automatic argon arc welding backing welding argon filling protection welding tooling, including an inflation groove buckled on the back of the weld joint. The inflation groove is arranged along the entire length of the weld joint, and a sealing structure is provided at the end. An inflation interface is provided on the inflation groove; the inflation groove is fixed by a U-shaped clamping plate and a wedge pin. The U-shaped clamping plate straddles the inflation groove and is respectively connected to two workpieces to be welded. The wedge pin is arranged on the back of the inflation groove and is inserted into the gap between the inflation groove and the U-shaped clamping plate.

[0006] The inflation groove is formed by segmented connection, and the adjacent segments are connected by a snap structure. The inflation interface is provided on each segment.

[0007] The cross-section of the inflation groove is semi-circular.

[0008] The advantages and positive effects of the present utility model are: by adopting the structure of buckling the inflation groove on the back of the weld joint, before the backing welding of the weld joint starts, the inflation groove is filled with argon gas. The argon gas isolates the deposited metal during the welding process from the air, avoiding the oxidation of the weld joint. Moreover, this structure can be combined with the weld joint alignment tooling to fix the inflation groove, eliminating the U-shaped clamping plate. The structure is simple and the operation is convenient. At the same time, this structure only fills the inflation groove with argon gas, with less argon gas consumption, which can save costs.

[0009] The structure of the present utility model is simple, easy to manufacture and use, and has low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a schematic structural diagram of the present utility model;

[0011] Figure 2 is a top view of the present utility model;

[0012] Figure 3 is a schematic diagram of the segmented structure of the inflation groove of the present utility model.

[0013] In the figure: 1, weld joint; 1-1, 1-2, workpieces to be welded; 2, inflation groove; 3, wedge pin; 4, inflation interface; 5, U-shaped clamping plate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In order to further understand the content, features and effects of the present utility model, the following embodiments are cited and detailed as follows in conjunction with the drawings:

[0015] Please refer to Figures 1 to 3, an automatic argon arc welding backing welding argon shielded welding tool, including an inflation groove 2 fastened to the back of the weld, the inflation groove 2 is arranged along the length of the weld, and a sealing structure is provided at the end, and an inflation interface 4 is provided on the inflation groove 2; the inflation groove 2 is fixed by a U-shaped clamping plate 5 and a wedge pin 3, the U-shaped clamping plate 5 spans the inflation groove 2 and is respectively connected to two to-be-welded parts 1-1 and 1-2, and the wedge pin 3 is arranged on the back of the inflation groove 2 and inserted in the gap between the inflation groove 2 and the U-shaped clamping plate 5.

[0016] In this embodiment, the inflatable groove 2 is connected in sections, and adjacent sections are connected by a snap-fit ​​structure, and each section is provided with the inflatable interface 4 for convenient combined use. The cross section of the inflatable groove 2 is semicircular, which is convenient for gas circulation.

[0017] When using, stick water-soluble paper on the front of the weld. Before welding, argon gas is filled into the filling groove 2 on the back of the weld through the vent. After the groove is filled with argon arc, peel off a small amount of water-soluble paper at the end of the weld and start the base welding.

[0018] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the scope of protection of the present invention.

Claims

1. An automatic argon arc welding backing welding argon shielded welding tool, characterized in that: It includes an inflation groove fastened to the back side of the weld, the inflation groove is arranged along the length of the weld, a sealing structure is arranged at the end, and an inflation interface is arranged on the inflation groove; the inflation groove is fixed by a U-shaped clamping plate and a wedge-shaped pin, the U-shaped clamping plate spans the inflation groove and is respectively connected to two to-be-welded parts, and the wedge-shaped pin is arranged on the back side of the inflation groove and inserted in the gap between the inflation groove and the U-shaped clamping plate.

2. The automatic argon arc welding backing welding argon shielded welding tool according to claim 1 is characterized in that: The inflation groove is formed by connecting sections, and adjacent sections are connected by a snap-fit ​​structure, and the inflation interface is provided on each section.

3. The automatic argon arc welding backing welding argon shielded welding tool according to claim 1 is characterized in that: The cross section of the inflation groove is semicircular.

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