CN115383257A

CN115383257A - Butt welding method and butt welding structure of alloy pipe

Info

Publication number: CN115383257A
Application number: CN202211008943.XA
Authority: CN
Inventors: 刘亚伟; 马金军; 雷振锋; 代磊; 王良平
Original assignee: Guangzhou Shipyard International Co Ltd
Current assignee: Guangzhou Shipyard International Co Ltd
Priority date: 2022-08-22
Filing date: 2022-08-22
Publication date: 2022-11-25

Abstract

The invention discloses a butt welding method and a butt welding structure of alloy pipes, and belongs to the technical field of ships. The butt welding method comprises the following steps: s1: the alloy pipes are provided with grooves, and the two alloy pipes are fixed after being butted; s2: the driving device drives the two alloy pipes to rotate around the center line of the pipe diameter; s3: the welding gun is fixedly arranged, the welding gun is ensured to be vertically positioned on the side surface of the alloy pipe through an electric arc generated by a tungsten needle, and the electric arc forms a welding seam on the inner surface of the alloy pipe from the groove base metal of the alloy pipe; s4: the welding wire on the welding wire disc is conveyed to the position where the electric arc contacts with the outer surface of the alloy pipe from the wire feeding pipe through the wire feeder, the welding wire is not automatically subjected to arc starting welding, and the welding wire is melted to fill the welding seam on the outer surface of the alloy pipe when the electric arc melts the base metal of the alloy pipe. The invention realizes automatic welding, is beneficial to batch butt welding, reduces the dependence degree on welding operation technology, reduces labor cost and improves welding efficiency.

Description

Butt welding method and butt welding structure of alloy pipe

Technical Field

The invention relates to the technical field of ships, in particular to a butt welding method and a butt welding structure of an alloy pipe.

Background

In the prior art, as shown in fig. 1 and 2, when a copper-nickel alloy pipe 1 ' is butt-welded, argon arc welding is adopted for welding, and a first welding seam 2 ', a second welding seam 3 ', a third welding seam 4 ' and a fourth welding seam 5 ' are formed in sequence from inside to outside. However, argon arc welding has the following disadvantages that firstly, the overall welding speed is slow, multiple welding is needed, for example, four welding is shown in fig. 2, and the welding efficiency is low; secondly, the requirement on welding operation skill is high, and the labor cost is high; and thirdly, argon arc welding belongs to manual welding, manual wire feeding and welding are needed, automatic welding cannot be realized, and butt welding of the copper-nickel alloy pipes in batches is not facilitated.

Therefore, a butt welding method and a butt welding structure of alloy pipes are needed to solve the above problems.

Disclosure of Invention

The invention aims to provide a butt welding method and a butt welding structure of an alloy pipe, which realize automatic welding, are beneficial to batch butt welding, reduce the degree of dependence on welding operation technology, reduce labor cost and improve welding efficiency.

In order to achieve the purpose, the invention adopts the following technical scheme:

in one aspect, a butt welding method is provided, including the steps of:

the alloy pipes are provided with grooves, and the two alloy pipes are fixed after being butted;

the driving device drives the two alloy pipes to rotate around the center line of the pipe diameter;

the welding gun is fixedly arranged, the welding gun is ensured to be vertically positioned on the side surface of the alloy pipe through an electric arc generated by a tungsten needle, and the electric arc self-melts the base material of the groove of the alloy pipe to form a welding seam on the inner surface of the alloy pipe;

and the welding wire on the welding wire disc is conveyed to the position where the electric arc contacts the outer surface of the alloy pipe from the wire feeding pipe through the wire feeder, the welding wire is not automatically subjected to arc starting welding, and the welding wire is also melted to fill the welding seam on the outer surface of the alloy pipe when the electric arc self-melts the base metal of the alloy pipe.

In some possible embodiments, the alloy pipes are provided with I-shaped grooves, and/or the assembly gap between two alloy pipes is 0-0.5mm.

In some possible embodiments, the driving device drives the alloy pipe to rotate at a constant speed.

In some possible embodiments, the amount of mismatching between two of the alloy tubes is no more than 0.5mm.

In some possible embodiments, the alloy tube is a copper nickel alloy tube and the welding wire is an ercunin solid welding wire.

In some possible embodiments, the alloy tube has a wall thickness of 2.5mm to 6mm, and/or a tube diameter of not less than 168mm.

In some possible embodiments, the arc is located vertically at the uppermost end of the alloy tube.

In some possible embodiments, when two alloy pipes are fixed, the alloy pipes are fixed by using positioning welding.

In some possible embodiments, the inside and outside of the alloy tube are filled with argon gas during welding to protect the weld.

On the other hand, the butt welding structure of the alloy pipe is formed by adopting the butt welding method.

The invention has the beneficial effects that:

according to the butt welding method and the butt welding structure of the alloy pipe, the alloy pipe is driven by the driving device to automatically rotate around the center line of the pipe diameter, the welding gun is fixed, the electric arc generated by the tungsten needle, the welding wire disc and the alloy pipe are automatically supplied with the welding wire, and the three parts and the alloy pipe are arranged at the positions. When the electric arc self-fuses the base metal of the alloy pipe, the welding wire is also fused, namely, a welding seam is formed on the outer surface of the alloy pipe while a welding seam is formed on the inner surface of the alloy pipe, so that a welding seam is formed, the alloy pipe is driven for one circle, the number of welding tracks is reduced, and the welding efficiency is improved.

Drawings

FIG. 1 is a cross-sectional view of a prior art Cu-Ni alloy tube prior to welding;

FIG. 2 is a cross-sectional view of a prior art tube of a copper-nickel alloy after welding;

FIG. 3 is a cross-sectional view of an alloy tube according to an embodiment of the present invention before welding;

FIG. 4 is a longitudinal sectional view in the welding of an alloy tube according to an embodiment of the present invention;

FIG. 5 is a cross-sectional view in the welding of an alloy tube according to an embodiment of the present invention;

fig. 6 is a cross-sectional view of an alloy pipe according to an embodiment of the present invention after welding.

In the figure:

1', a copper-nickel alloy tube; 2', a first welding line; 3', a second welding seam; 4', a third welding seam; 5', a fourth welding seam; l', an assembly gap; m', included angle of groove;

1. an alloy pipe; 2. welding; l, assembling clearance; B. wall thickness; D. pipe diameter; x, a first direction;

100. a welding gun; 101. a magnetic nozzle; 102. a tungsten needle; 10A, an electric arc; 200. a wire feeding pipe; 300. and (4) welding wires.

Detailed Description

In order to make the technical problems solved, technical solutions adopted and technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, unless otherwise explicitly specified or limited, the terms "connected," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in a specific case to those of ordinary skill in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The present embodiment provides a butt welding structure of an alloy pipe, which is formed by a butt welding method. The embodiment also provides a butt welding method, as shown in fig. 3 to 6, including the following steps:

s1: the alloy pipes 1 are provided with grooves, and the two alloy pipes 1 are fixed after being butted, so that a gap is reserved between the two alloy pipes 1;

s2: the driving device drives the two alloy pipes 1 to rotate around the center line of the pipe diameter D;

s3: the welding gun 100 is fixedly arranged, the welding gun 100 is enabled to be vertically positioned on the side face of the alloy pipe 1 through an electric arc 10A generated by a tungsten needle 102, and the electric arc 10A forms a welding seam 2 on the inner surface of the alloy pipe 1 from a groove base metal of the alloy pipe 1;

s4: the welding wire 300 on the welding wire disc is conveyed from the wire feeding pipe 200 to the position where the electric arc 10A contacts with the outer surface of the alloy pipe 1 through the wire feeder, the welding wire 300 does not automatically start arc welding, and the electric arc 10A melts the welding wire 300 to fill the welding seam 2 on the outer surface of the alloy pipe 1 when melting the base metal of the alloy pipe 1.

The alloy pipe 1 is driven by a driving device to automatically rotate around the center line of the pipe diameter D, the welding gun 100 is fixed, the electric arc 10A generated by the tungsten needle 102, the welding wire 300 are automatically supplied by the welding wire disc, and the three parts and the alloy pipe 1 are arranged in position, after the three parts are started, the tungsten needle 102 and the wire feeding pipe 200 are relatively rotated relative to the periphery of the alloy pipe 1 due to the rotation of the alloy pipe 1 around the center line of the pipe diameter D, the welding wire 300 is automatically fed to the position of the electric arc 10A, the electric arc 10A melts through the joint of the whole alloy pipe 1 to form a welding seam 2 on the inner surface of the pipe, and the melted welding wire 300 ensures that the welding seam 2 on the outer surface of the joint of the alloy pipe 1 is full, the whole process can be welded by only one welding, the single-pass automatic welding and double-sided forming of the single-face is realized, the welding quality of the copper-nickel pipe is obviously improved, the number of the welding passes is reduced, and the welding efficiency is improved; and automatic welding is realized, and the alloy pipes 1 are butt-welded in batches. Specifically, the speed of the welding wire 300 conveyed by the wire feeder, the position of the tungsten needle 102 and the like can be determined by referring to the prior art, tests and the like, so that the dependence on welding operation skills is reduced, and the labor cost is reduced.

After welding of one group of alloy pipes 1 is completed, the alloy pipes are detached from the driving device, and welding of another group of alloy pipes 1 is performed.

As shown in fig. 1, a butt-jointed cupronickel alloy pipe 1 ' in the prior art is generally provided with a V-shaped groove, the included angle M ' of the groove is about 60 degrees, and an assembly gap L ' of about 1mm is reserved for assembly, so as to ensure that the root of the groove is melted through and formed, and thus the welding effect is ensured. However, the V-groove machining results in a low tube utilization rate, and the groove leaving the fitting gap L' increases the welding workload and the consumption of welding materials such as welding wires. In one embodiment, as shown in fig. 3, the fitting clearance L between the two alloy tubes 1 is 0 to 0.5mm. Because the inner surface of the alloy pipe 1 is welded in a mode of melting the welding wire 300 on the outer surface, on the premise of ensuring the penetration of the weld, the adoption of the method has the advantages that the gaps are not left or smaller gaps are left, the welding workload and the consumption of welding materials such as the welding wire 300 are reduced, the working efficiency is improved, and the cost is reduced. Similarly, in an embodiment, the alloy pipe 1 is provided with an I-shaped groove (not shown in the figure), and the groove is smaller than the opening of the V-shaped groove, so that compared with the traditional V-shaped groove, the scheme can improve the welding effect and reduce the welding workload and the consumption of welding materials.

In one embodiment, alloy tube 1 is a copper nickel alloy tube and welding wire 300 is ercunin solid wire to ensure welding. In one embodiment, the wall thickness B of the alloy pipe 1 is 2.5mm-6mm, so that the welding effect can be ensured. The diameter D of the alloy pipe 1 generally used in a ship is large, and in one embodiment, the diameter D of the alloy pipe 1 is not less than 168mm. For big pipe diameter D copper nickel alloy pipe argon arc welding arc stop point is many among the traditional structure, and welded joint is many, easily leads to connecting position welding seam 2 quality to descend, and this scheme welds in succession, fuses of high qualityly, reduces welded joint quantity, improves welding quality. In one embodiment, the misalignment between the two alloy pipes 1 is not more than 0.5mm, so that the structural precision of the alloy pipes 1 after butt welding is improved, and the product quality is improved.

In one embodiment, when the two alloy pipes 1 are fixed, the two alloy pipes 1 are fixed by adopting positioning welding, the positions of the two alloy pipes 1 are fixed, the welding effect is ensured, and the positioning welding process is simple and reliable.

Further, the welding gun 100, the driving device, the wire reel and the wire feeder all adopt the existing structures, which are not described again, and during assembly, the welding gun 100 is ensured not to make mechanical swing, specifically, the welding gun 100 comprises a magnetic nozzle 101, a tungsten needle 102 and other structures; the diameter of the tungsten needle 102 is large enough, a welding seam 2 is formed on the inner surface of the alloy tube 1 from the I-shaped groove base metal of the alloy tube 1 through the electric arc 10A generated by the large-diameter tungsten needle 102, and meanwhile, the electric arc 10A generated by the large-diameter tungsten needle 102 melts the ERCuNi solid welding wire to fill the welding seam 2 on the outer surface of the alloy tube 1; the driving device drives the alloy pipe 1 to rotate at a constant speed, so that the welding seam 2 is ensured to be uniform, the alloy pipe rotates towards a first direction X in the embodiment, and the alloy pipe can also rotate in the opposite direction in other embodiments; the arc 10A is vertically positioned at the uppermost end of the alloy tube 1 to avoid structural interference. In one embodiment, the inside and outside of the alloy tube 1 are filled with argon gas throughout the welding process to protect the weld 2 and prevent oxidation of the weld 2. By arranging the copper-nickel alloy pipe with the wall thickness B of 2.5mm-6mm, not forming a groove or an I-shaped groove in butt joint, not leaving an assembly gap L or having a smaller assembly gap L, the effect of single-side single-pass welding and double-side molding is ensured, and meanwhile, the consumption of protective gas such as argon can be reduced.

Specifically, the parameters of the alloy pipe 1 during butt welding are shown in table 1 below, and reference may be made thereto.

TABLE 1

In this embodiment, the example of welding the phi 168 × 6mm copper-nickel alloy pipe butt joints by argon arc welding and the present solution is taken as an example, and the efficiency and material consumption are as follows in table 2.

TABLE 2

Compared with the traditional copper-nickel alloy pipe argon arc welding, the copper-nickel alloy pipe butt joint efficient automatic welding method has the following advantages: firstly, beveling is not needed, and gapless assembly is realized, so that the processing and assembly quality and efficiency of the pipe can be improved, the welding amount is reduced, and the loss of the copper-nickel alloy pipe is reduced; secondly, beveling is not needed, and gapless assembly is carried out, so that the consumption of welding materials is reduced, the usage amount of the welding wire 300 is reduced by about 32%, and the protective gas can be saved by 95%; thirdly, because single-side single-pass welding and double-side forming can be realized, the welding efficiency is improved by 17.3 times compared with argon arc welding; fourthly, automatic wire feeding and automatic welding can be realized, batch production can be realized, the requirement on welding operation skills is low, and the labor cost is low; fifthly, continuous welding is performed, the fusion quality is good, the number of welding joints is reduced, and the welding quality is improved.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A butt welding method, comprising the steps of:

the alloy pipes (1) are provided with grooves, and the two alloy pipes (1) are fixed after being butted;

the driving device drives the two alloy pipes (1) to rotate around the center line of the pipe diameter (D);

the welding gun (100) is fixedly arranged, the welding gun (100) is enabled to be vertically positioned on the side face of the alloy pipe (1) through an electric arc (10A) generated by a tungsten needle (102), and the electric arc (10A) melts a groove base metal of the alloy pipe (1) to form a welding seam (2) on the inner surface of the alloy pipe (1);

the welding wire (300) on the welding wire disc is conveyed to an electric arc (10A) from a wire feeding pipe (200) through a wire feeder and is in contact with the outer surface of the alloy pipe (1), the welding wire (300) is not automatically subjected to arc starting welding, and the welding wire (300) is further melted when the base metal of the alloy pipe (1) is automatically melted by the electric arc (10A) to fill up the welding seam (2) on the outer surface of the alloy pipe (1).

2. The butt welding method according to claim 1, wherein the alloy tubes (1) are provided with an I-shaped bevel, and/or an assembly gap (L) between the two alloy tubes (1) is 0-0.5mm.

3. The butt welding method according to claim 1, wherein the driving device drives the alloy tube (1) to rotate at a constant speed.

4. Butt welding method according to claim 1, characterized in that the amount of misalignment between two said alloy tubes (1) does not exceed 0.5mm.

5. The butt welding method according to claim 1, wherein the alloy tube (1) is a cupronickel tube and the welding wire (300) is an ercunin solid welding wire.

6. The butt welding method according to claim 1, characterized in that the wall thickness (B) of the alloy tube (1) is 2.5mm to 6mm, and/or the tube diameter (D) of the alloy tube (1) is not less than 168mm.

7. The butt welding method according to any one of claims 1 to 6, wherein the arc (10A) is vertically positioned at the uppermost end of the alloy tube (1).

8. The butt welding method according to any one of claims 1 to 6, wherein when the two alloy pipes (1) are fixed, tack welding is used for fixing.

9. A butt welding method according to any one of claims 1-6, characterized in that the inside and outside of the alloy tube (1) are filled with argon gas during welding to protect the weld joint (2).

10. A butt-welded structure of an alloy pipe, characterized by being formed by the butt-welding method according to any one of claims 1 to 9.