CN216632972U

CN216632972U - Argon-filling-free welding structure for preventing back surface oxidation by backing argon arc welding at pipeline mounting port

Info

Publication number: CN216632972U
Application number: CN202122935628.9U
Authority: CN
Inventors: 李雪梅; 李伯承; 明宇; 吕振亮; 王余来
Original assignee: Sinopec Fourth Construction Co Ltd
Current assignee: Sinopec Fourth Construction Co Ltd
Priority date: 2021-11-26
Filing date: 2021-11-26
Publication date: 2022-05-31
Anticipated expiration: 2031-11-26

Abstract

The utility model discloses an argon-filling-free welding structure for preventing back oxidation by argon arc welding bottoming of a pipeline mounting port, which comprises a fixed pipeline pipe orifice and a mounting pipe section pipe orifice butted with the fixed pipeline pipe orifice, wherein lining rings matched with the fixed pipeline pipe orifice and the mounting pipe section pipe orifice are arranged on the inner sides of the butting welding ports of the fixed pipeline pipe orifice and the mounting pipe section pipe orifice, the lining rings are connected with the inner sides of the fixed pipeline pipe orifice through intermittent welding seams at intervals, and the lining rings are connected with the fixed pipeline and the mounting pipe section groove through segmented welding seams. The utility model adopts the austenitic stainless steel lining ring which is inosculated with the inner side of the butt weld crater as a tool, when the crater is assembled, the lining enters the interior of the mouth of the butt weld crater, and when the crater is welded by argon arc welding and backing welding, the lining ring isolates the thermal influence of deposited metal and pipelines in the welding process from air, thereby avoiding the oxidation of the crater. Can meet the relevant design requirements of the nickel alloy pipeline and can be suitable for welding the parts which can not be filled with argon for the nickel alloy pipeline and the stainless steel pipeline. The utility model has simple structure, convenient manufacture and use and low cost.

Description

Argon-filling-free welding structure for preventing back surface from being oxidized by argon arc welding bottoming of pipeline mounting port

Technical Field

The utility model relates to a welding structure, in particular to a structure for preventing back oxidation by argon-arc welding priming without argon filling at a pipeline mounting port.

Background

At present, the nickel alloy pipeline is widely applied to various devices in petrochemical industry. In the welding construction process of the nickel alloy pipeline, the welding process requirement is strict, the temperature between channels is required to be less than or equal to 100 ℃, multilayer multi-channel welding is carried out, particularly because the nickel alloy pipeline is easy to oxidize, when argon arc welding is adopted for priming, the front side of a welding seam is generally protected by argon sprayed by a welding handle, high-temperature welding seam metal on the back side of the welding seam is easy to contact with air to cause oxidation, and argon gas needs to be filled to protect the back side. For the prefabricated welding openings of a prefabrication factory, a sponge blocking mode on two sides can be adopted, or an argon filling-free tool can be moved, and argon filling protection is carried out inside; water-soluble paper can be adopted for plugging and argon filling of two sides of the pipeline for welding opening installation, and the water-soluble paper can be flushed away during a hydrostatic test. However, the medium of some engineering pipelines does not allow the residues of water-soluble paper and organic matters, especially the local replacement of the pipeline section in the overhaul process, and the 100% flushing away of the water-soluble paper cannot be guaranteed, so that the water-soluble paper cannot be used for plugging, for example, the mounting port is welded during the overhaul of the styrene gas medium pipeline, and the argon arc welding bottoming of the pipeline prevents the back surface from being oxidized to become a difficult problem in the engineering.

SUMMERY OF THE UTILITY MODEL

The utility model provides an argon-filling-free welding structure for preventing back oxidation by backing argon arc welding of a pipeline mounting port, which aims to solve the technical problems in the prior art.

The technical scheme adopted by the utility model for solving the technical problems in the prior art is as follows: the utility model provides a pipeline installation mouth argon arc welds and bottoms exempts from argon-filling welded structure who prevents back oxidation, includes the fixed pipeline mouth of pipe and rather than the installation pipeline section mouth of pipe of butt joint the fixed pipeline mouth of pipe with installation pipeline section orificial butt weld mouth inboard is equipped with rather than anastomotic junk ring, the junk ring with the fixed pipeline mouth of pipe inboard is through the intermittent weld joint that continues of interval, the junk ring with fixed pipeline with installation pipeline section groove adopts the segmentation welded joint.

The lining ring is formed by rolling thin plates, and the butt joints of the thin plates are connected by welding seams.

The width of the stainless steel plate is 20-30mm, the thickness of the stainless steel plate is less than or equal to 4mm, and the length of the stainless steel plate is equal to the inner circumference of the inner opening of the fixed pipeline.

The interval of the intermittent welding line is 100mm, and the welding length is 10 mm.

The interval of the sectional welding lines is 300mm, and the welding length is 100 mm.

The length of the stainless steel lining ring which is lined into the pipe orifice of the fixed pipeline is 7-8 mm.

The utility model has the advantages and positive effects that: an austenitic stainless steel lining ring matched with the inner side of the butt weld opening is used as a tool, when the weld opening is assembled, the lining enters the inner part of the butt joint pipe opening, and when the argon arc welding backing welding of the weld opening is carried out, the lining ring enables deposited metal and pipeline heat influence in the welding process to be isolated from air, so that the oxidation of the weld opening is avoided. Can meet the relevant design requirements of the nickel alloy pipeline and can be suitable for welding the parts which can not be filled with argon for the nickel alloy pipeline and the stainless steel pipeline. The utility model has simple structure, convenient manufacture and use and low cost.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

In the figure: 1. a gasket; 2. fixing the pipe orifice of the pipeline; 3. and (5) installing a pipe section pipe orifice.

Detailed Description

In order to further understand the contents, features and effects of the present invention, the following embodiments are illustrated and described in detail with reference to the accompanying drawings:

referring to fig. 1, an argon-filling-free welding structure for preventing back surface oxidation during argon arc welding priming of a pipeline installation opening comprises a fixed pipeline pipe opening 2 and an installation pipe section pipe opening 3 butted with the fixed pipeline pipe opening 2, wherein lining rings 1 matched with the fixed pipeline pipe opening 2 and the installation pipe section pipe opening 3 are arranged on the inner sides of butt welding openings of the fixed pipeline pipe opening 2 and the installation pipe section pipe opening 3, the lining rings 1 are connected with the inner sides of the fixed pipeline pipe opening 2 through spaced intermittent welding seams, and grooves of the lining rings 1 and the fixed pipeline pipe opening 2 and the installation pipe section pipe opening 3 are respectively connected through segmented welding seams.

The material of the lining ring should ensure that the group pipe is not carburized, and in order to prevent the group pipe from being carburized, the lining ring should be made of austenitic stainless steel or nickel-based materials.

In the embodiment, the gasket 1 is formed by rolling thin plates, so that the gasket is convenient to manufacture and install, and the butt joints of the thin plates are connected by welding seams. The stainless steel plate is 20-30mm wide, less than or equal to 4mm thick, and the length is equal to the inner circumference of the pipe orifice of the fixed pipe. The interval of the intermittent welding line is 100mm, and the welding length is 10 mm. The interval of the sectional welding lines is 300mm, and the welding length is 100 mm. The length of the lining ring 1 lining the inside of the fixed pipeline pipe orifice 2 is 7-8 mm.

The welding structure is not suitable for pipelines with higher requirements on the internal welding smoothness of the pipelines, such as oxygen lines and the like.

Now, taking the inlet pipeline of the heat exchanger of the styrene device as an example, the application of the welding structure is described, the inlet pipeline of the heat exchanger of the styrene device is made of N08810, the pipe diameter is phi 914mm, and the thickness is 19 mm. The welding process requires argon arc welding for priming, welding rod arc welding for filling the cover surface, and no organic matter remains in the pipe during construction. The welding structure is adopted to carry out back protection of argon arc welding in the specific construction process.

Before the group is matched, a mechanical method is adopted for groove processing, appearance inspection is carried out after the groove processing, and the defects of cracks, layering and the like cannot be generated on the surface of the groove.

And then, firstly inserting the lining ring into the pipe orifice of the fixed pipeline, wherein the insertion depth is 7-8 mm, fixing the end part of the lining ring into the pipe orifice of the fixed pipeline by adopting argon arc welding, positioning the lining ring, and adopting welding wire type ERNiCr-3, intermittent welding at intervals of every 100mm, wherein the welding length is 10 mm. And then welding the joint of the lining ring at the end and the tail by adopting welding wires corresponding to the material of the lining ring.

In the weld crater assembling process, after the weld craters are centered, the lining ring is inserted into the pipe orifice of the installation pipe section, the gap between the lining ring and the pipe orifice of the installation pipe section is adjusted to be not more than 1mm, and then the alignment gap and the misalignment amount are adjusted, wherein the alignment gap is 3-4mm, and the misalignment amount is 1-2 mm.

And after the lining ring is installed, respectively welding the lining ring with the pipe orifice of the installation pipe section and the pipe orifice of the fixed pipeline, and welding the lining ring in a segmented mode by welding 100mm at intervals of 300mm by adopting argon arc welding to prevent the lining ring from deforming until the whole circle of welding seam is welded.

After the construction of the argon filling-free structure is finished, welding beads are firstly blanked by welding wires ERNiCr-3 argon arc welding for 2mm, then are blanked by welding wires ERNiCrCoMo-1 argon arc welding for 2mm to 3mm, and after PT and RT are checked to be qualified, welding rods ENiCrCoMo-1 welding rods are used for arc welding to fill the cover surfaces. The inter-channel temperature in the welding process is less than 100 ℃; the joints of each weld pass should be staggered.

Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and those skilled in the art can make many modifications without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. The utility model provides a pipeline installation mouth argon arc welds exempts from argon-filling welded structure who prevents back oxidation of bottoming, including the fixed pipeline mouth of pipe and rather than the installation pipeline section mouth of pipe of butt joint, its characterized in that the fixed pipeline mouth of pipe with the orificial butt weld mouth inboard of installation pipeline section is equipped with rather than anastomotic junk ring, the junk ring with the fixed pipeline mouth of pipe inboard is through the intermittent weld joint in interval, the junk ring with fixed pipeline with installation pipeline section groove adopts the segmentation welded joint to connect.

2. The argon arc welding priming structure for the pipeline installation port, which is free of argon filling and prevents back oxidation, according to claim 1, is characterized in that the lining ring is formed by rolling stainless steel plates, and the butt joints of the stainless steel plates are connected through welding seams.

3. The argon arc welding priming structure for the pipe installation port, which is free of argon filling and prevents back surface oxidation, according to claim 2, wherein the stainless steel plate is 20-30mm wide, 4mm or less thick and equal to the inner circumference of the pipe hole of the fixed pipe.

4. The argon arc welding backing argon-filling-free welding structure for the pipeline installation port, which is used for preventing back surface oxidation, as claimed in claim 1, is characterized in that the interval of the intermittent welding line is 100mm, and the welding length is 10 mm.

5. The argon arc welding backing argon-filling-free welding structure for the pipeline installation port to prevent the back surface from being oxidized as claimed in claim 1, wherein the interval of the segmented welding seams is 300mm, and the welding length is 100 mm.

6. The argon arc welding backing argon-filling-free welding structure for the pipeline installation port to prevent the back surface from being oxidized according to claim 1, wherein the length of the lining ring lining the inside of the fixed pipeline pipe orifice is 7-8 mm.