CN110142532A - Argon filling device for branch pipe seat welding - Google Patents

Abstract

The invention relates to an argon-filling device for branch pipe seat welding, comprising: an argon-filling sleeve used for filling the upper part of the weld seam with argon gas from one side of the branch pipe seat; Core tube; wherein, the argon-filled core tube can be axially inserted into the argon-filled casing, and the branch tube seat welding argon filling device is used to realize the successful replacement of the thin-walled main tube upper branch tube seat (BOSS head) , effectively reducing the problems of poor weld surface formation and high parent pipe collapse caused by non-technical factors such as uneven argon filling and molten pool instability, ensuring the quality and efficiency of welding and branch pipe seat (BOSS head) replacement work .

Description

Argon filling device for branch pipe seat welding

technical field

The invention relates to the technical field of nuclear power maintenance, in particular to an argon charging device for branch pipe seat welding.

Background technique

According to feedback from manufacturing and installation experience, there are defects such as excessive slag inclusion and lack of fusion in the welds connecting some nuclear-grade branch pipe sockets (also known as BOSS heads) and the main pipe on site in nuclear power plants, and weld defects need to be dealt with. The most direct solution It is an in-service replacement of the BOSS head.

For the replacement of the BOSS head, the key lies in the welding of the new BOSS head, and the welding quality is an important criterion for considering the success of the replacement work. During the replacement of the BOSS head in the nuclear power plant, it was found that quite a few BOSS heads were welded to the thin-walled main pipe (the wall thickness of the main pipe is less than 5mm). The welding process is prone to problems such as instability of the molten pool and poor weld formation, which seriously affects the welding quality and the time limit for replacing the BOSS head.

Internationally, there is no relevant technology for in-service replacement of nuclear-grade BOSS heads, and there is no related set of special tools for BOSS head replacement, including special tools for auxiliary welding.

At present, for the replacement of the BOSS head on the thin-walled main pipe in China, the self-designed simple argon filling device as shown in Figure 1 has been used, and the argon filling method is used from the top of the weld (BOSS head side). In order to create an oxygen-free or low-oxygen environment around the back of the weld, a large flow rate of argon gas is required, and a high argon consumption is required. In addition, this method has high requirements on the stability of the argon gas flow, and is prone to problems such as poor weld surface formation caused by unstable argon filling effect.

Contents of the invention

The technical problem to be solved by the present invention is to provide an argon filling device for branch pipe seat welding.

The technical solution adopted by the present invention to solve the technical problem is to construct a welding argon charging device for branch pipe base, which is characterized in that it includes:

An argon-filled sleeve used to fill the upper part of the weld with argon from the side of the branch pipe seat;

An argon-filled core tube for filling the lower part of the weld with argon from the back of the parent tube;

Wherein, the argon-filled core tube can be axially inserted into the argon-filled casing.

Preferably, the argon-filled sleeve includes:

bushing body; and

A gland arranged on the outer periphery of the bushing body for covering the argon-filled bushing on the top of the branch socket for positioning and sealing.

Preferably, at least one first argon gas inlet for filling argon gas is provided on the casing body outside the gland; at least one first argon outlet.

Preferably, the argon-filled sleeve is provided with a first installation hole at the top of the sleeve body, and a sleeve end plug with a second installation hole at the bottom;

When the argon-filled core tube is axially inserted into the argon-filled sleeve through the first installation hole and the second installation hole, the sleeve body, the sleeve end plug and the argon-filled core tube The outer surfaces cooperate to form an inner space for the flow of argon gas.

Preferably, the sleeve end plug is provided with at least one third argon outlet for argon to flow out of the inner space;

Preferably, the first mounting hole is provided with a first thread;

The outer surface of the tube wall of the argon-filled core tube is provided with a second thread that cooperates with the first thread and inserts the argon-filled core tube into the argon-filled casing with an adjustable depth.

Preferably, the first end of the argon-filled core tube is provided with a second argon inlet for filling argon, and the second end is provided with at least one second argon outlet for argon to flow out;

The inner surface of the tube wall of the argon-filled core tube is surrounded to form a hollow cavity for argon to flow through.

Preferably, the second argon gas outlet is arranged on the tube wall of the second end of the argon-filled core tube, and the end of the tube wall of the second end of the argon-filled core tube is also provided with a The argon gas flowing out of the gas outlet is blocked back to the argon space baffle at the back of the main pipe, and the fixing piece for fixing the argon space baffle.

Preferably, the fixing member includes a nut and a screw cooperating with the nut for clamping the argon space baffle.

Preferably, the argon space baffle is made of high temperature resistant tape material.

Implementing the present invention has the following beneficial effects: the argon gas circulating in the argon-filled casing is charged from the first argon gas inlet, and flows out from the first argon gas outlet through the casing body, ensuring that the inside of the branch pipe seat (BOSS head) (welding The air from the upper part of the weld is exhausted to create an oxygen-free or ultra-low oxygen environment on the upper part of the weld; the argon gas that enters from the second argon inlet and circulates in the hollow cavity passes through the argon space baffle from the second argon outlet Radial reflow, mixed with argon gas flowing out from the first argon gas outlet, discharges the air around the lower part of the weld and within a certain range on the back of the main pipe, creating an oxygen-free or ultra-low oxygen environment.

The argon filling device for branch pipe seat welding realizes the successful replacement of the upper branch pipe seat (BOSS head) of the thin-walled main pipe, and effectively reduces the poor shape of the weld surface caused by non-technical factors such as uneven argon filling and molten pool instability. Problems such as the high collapse of the main pipe and the high amount of collapse of the main pipe ensure the quality and efficiency of the welding and the replacement of the branch pipe seat (BOSS head).

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and embodiment, in the accompanying drawing:

Fig. 1 is the structural representation of the simple and easy argon filling device commonly used in this field;

Fig. 2 is a schematic structural view of the argon filling device for branch pipe seat welding of the present invention;

Fig. 3 is a schematic diagram of the use of the argon charging device for branch pipe seat welding of the present invention.

Detailed ways

As shown in Figure 2, the welding argon filling device of the branch pipe seat of the present invention includes: an argon filling sleeve 2 for filling the upper part of the weld seam from the side of the branch pipe seat 11; An argon-filled core tube 1 filled with argon at the bottom; wherein, the argon-filled core tube 1 can be inserted into the argon-filled casing 2 along the axial direction.

The argon-filled bushing 2 includes: a bushing body; and a gland 6 arranged on the periphery of the bushing body for covering the argon-filled bushing 2 on the top of the branch socket 11 for positioning and sealing.

In this embodiment, the gland 6 can be a circular plate structure, and its radius is close to or larger than the outer diameter of the head of the branch seat 11, so that it can cover the head of the branch seat 11 sufficiently. , and then make the branch pipe seat welding argon filling device installed on the branch pipe seat 11 according to the positioning of the gland 6 .

Further, the gland 6 ensures that the argon gas will not overflow or seep out from the head of the branch pipe seat 11 during the argon filling process, so as to ensure the uniformity of argon filling and save argon gas.

It can be understood that the gland 6 can also have other structures and other sizes, as long as the above-mentioned positioning, installation and sealing functions can be realized, and no specific limitation is made here.

At least one first argon gas inlet 8 for filling argon gas is provided on the casing body outside the gland 6; an argon gas outlet 9 .

In this embodiment, the first argon gas inlet 8 may be provided with one, or may be provided in multiples circumferentially on the bushing body, or may be two symmetrically arranged along the axis of the bushing body.

It can be understood that the number of the first argon gas inlets 8 can be set according to actual needs, and the aperture of the first argon gas inlets 8 can also be set according to actual needs, which is not specifically limited here.

Further, the first argon gas outlet 9 may be provided with one, or a plurality of outlets arranged circumferentially on the casing body, or two arranged symmetrically along the axis of the casing body.

It can be understood that the number of the first argon outlets 9 can be set according to actual needs, and the aperture of the first argon outlets 9 can also be set according to actual needs, which is not specifically limited here.

In this embodiment, the argon-filled bushing 2 is provided with a first mounting hole at the top of the bushing body, and a bushing end plug 3 with a second mounting hole at the bottom.

When the argon-filled core tube 1 is inserted into the argon-filled sleeve 2 through the first installation hole and the second installation hole in the axial direction, the sleeve body, the sleeve end plug 3 and the outer surface of the argon-filled core tube 1 cooperate to form an argon supply tube. The inner space 201 where air flows.

It can be understood that the size of the inner space 201 can be adjusted by the size of the casing body, the casing end plug 3 and the argon-filled core tube 1 . The formation of the inner space 201 reduces the space required to be filled with argon on the upper part of the branch tube base 11, and makes the head of the branch tube base 11 filled with argon more uniformly, and the argon filling effect is better.

In some embodiments, the sleeve end plug 3 is provided with at least one third argon outlet for argon to flow out from the inner space 201, so that the argon flowing in the inner space 201 is filled with the third argon outlet to flow out and be discharged. In the environment of branch pipe seat 11 head.

Further, the first installation hole is provided with a first thread; the outer surface of the tube wall of the argon-filled core tube 1 is provided with a thread that matches the first thread, and the argon-filled core tube 1 can be inserted into the argon-filled casing 2 with an adjustable depth. the second thread.

It can be understood that the inner wall surface of the second installation hole of the bushing end plug 3 can be smoothed. It is also possible to provide a third thread matched with the second thread. In this case, the casing end plug 3 needs to be finished to make the centering accurate.

In this embodiment, the position of the end of the argon-filled core tube 1 can be adjusted reasonably according to the needs of the site. Further, the argon-filled core tube 1 is inserted into the first installation hole, and the installation position is adjusted. When the argon-filled core tube 1 is adjusted and installed to a predetermined position, the sleeve end plug 3 is screwed into the second installation hole. The argon-filled core tube 1 abuts against the bottom of the bushing body for installation and fixation.

Understandably, it can be fixed by welding. Further, the locking can be performed by locking pieces arranged on the circumferential sides of the sleeve body and the sleeve end plug 3 . Further, the bottom of the casing body faces the casing end plug 3 and is provided with a positioning groove or a positioning thin column, and the casing end plug 3 is correspondingly provided with a positioning thin column or a positioning groove, which is more convenient for positioning and installation, and can enhance installation stability.

In this embodiment, the first end of the argon-filled core tube 1 is provided with a second argon inlet 102 for filling argon, and the second end is provided with at least one second argon outlet 10 for argon to flow out. .

Further, the inner surface of the tube wall of the argon-filled core tube 1 is surrounded to form a hollow cavity 101 for argon gas to flow through. Argon gas is filled into the second argon gas inlet 102 and circulates in the central cavity 101 , and finally flows out through the second argon gas outlet 10 .

The second argon gas outlet 10 is arranged on the tube wall of the second end of the argon-filled core tube 1, and the end of the tube wall at the second end of the argon-filled core tube 1 is also provided with an argon for flowing out of the second argon gas outlet 10. The gas is blocked back to the argon space baffle plate 7 on the back of the main pipe 12, and the fixture for fixing the argon space baffle plate 7.

In this embodiment, the second argon gas outlet 10 may be provided with one, or multiple outlets arranged circumferentially on the tube wall of the argon-filled core tube 1, or two outlets symmetrically arranged along the axis of the argon-filled core tube 1. indivual.

It can be understood that the number of the second argon outlets 10 can be set according to actual needs, and the aperture of the second argon outlets 10 can also be set according to actual needs, which is not specifically limited here.

Further, the fixing member includes a nut 4 and a screw 5 cooperating with the nut 4 for clamping the argon space baffle 7 . The argon space baffle 7 is a baffle made of high-temperature-resistant tape material. It is understandable that other materials can be used to make the argon space baffle 7 according to actual needs.

A hole close to the diameter of the screw 5 is provided in the middle of the argon space baffle plate 7 , through which the hole is screwed into the screw 5 , and then the nut 4 is matched to complete the clamping work. When the argon space baffle plate 7 needs to be replaced, it is only necessary to unscrew the screw 5 in reverse.

In some embodiments, the argon space baffle 7 can be clamped by the cooperation between the first pressing plate and the second pressing plate. It can be understood that as long as the clamping of the argon space baffle 7 is achieved.

As shown in Figure 3, in this embodiment, the argon gas circulating in the argon-filled sleeve 2 is filled from the first argon gas inlet 8, and flows out from the first argon gas outlet 9 through the sleeve body, ensuring that the branch pipe seat 11 (BOSS head) The air inside (the upper part of the welding seam) is discharged to create an oxygen-free or ultra-low oxygen environment on the upper part of the welding seam; the argon gas that enters from the second argon gas inlet 102 and circulates in the hollow cavity 101, from the second argon gas inlet 102 The second argon gas outlet 10 flows back radially through the argon space baffle plate 7, mixes with the argon gas flowing out from the first argon gas outlet 9, and discharges the air in a certain range around the lower part of the weld seam and the back of the main pipe 12 to create an oxygen-free or In an ultra-low oxygen environment, after the welding is completed, the argon filling device can be directly lifted up to weld the branch pipe seat.

The argon filling device for branch pipe seat welding realizes the successful replacement of the branch pipe seat 11 (BOSS head) on the thin-walled main pipe 12, and effectively reduces the weld surface damage caused by non-technical factors such as uneven argon filling and molten pool instability. Problems such as poor forming and high collapse of the main pipe 12 ensure the quality and efficiency of the welding and branch pipe seat 11 (BOSS head) replacement work.

It can be understood that the above examples only express the preferred implementation of the present invention, and its description is relatively specific and detailed, but it should not be interpreted as limiting the patent scope of the present invention; it should be pointed out that for those of ordinary skill in the art In other words, on the premise of not departing from the concept of the present invention, the above-mentioned technical features can be freely combined, and some modifications and improvements can also be made, all of which belong to the protection scope of the present invention; All equivalent transformations and modifications should fall within the scope of the claims of the present invention.

Claims (10)

1. An argon filling device for branch pipe seat welding, characterized in that it comprises: An argon filling sleeve (2) for filling the upper part of the weld with argon from one side of the branch pipe seat (11); An argon-filled core tube (1) for filling the lower part of the weld with argon from the back of the main tube (12); Wherein, the argon-filled core tube (1) can be axially inserted into the argon-filled casing (2). 2. The argon filling device for branch pipe seat welding according to claim 1, characterized in that, the argon filling sleeve (2) comprises: bushing body; and A gland (6) arranged on the outer periphery of the sleeve body for covering the argon-filled sleeve (2) on the top of the branch socket (11) for positioning and sealing. 3. The welding argon charging device for branch pipe seat according to claim 2, characterized in that at least one first argon gas inlet for charging argon gas is provided on the casing body outside the gland (6) (8); and at least one first argon outlet (9) for argon to flow out is provided on the casing body inside the gland (6). 4. The argon filling device for branch pipe seat welding according to claim 2, characterized in that, the argon filling sleeve (2) is provided with a first installation hole on the top of the sleeve body, and a second installation hole at the bottom. Casing end plug (3) for the hole; When the argon-filled core tube (1) is axially inserted into the argon-filled sleeve (2) through the first installation hole and the second installation hole, the sleeve body, the sleeve end plug ( 3) cooperate with the outer surface of the argon-filled core tube (1) to form an inner space (201) for the flow of argon gas. 5. The argon filling device for branch tube seat welding according to claim 4, characterized in that, the sleeve end plug (3) is provided with at least one third argon for argon to flow out from the inner space (201) gas outlet. 6. The argon filling device for branch pipe seat welding according to claim 4, characterized in that, the first mounting hole is provided with a first thread; The outer surface of the tube wall of the argon-filled core tube (1) is provided with a thread that matches the first thread, and the argon-filled core tube (1) is inserted into the argon-filled casing (2) in an adjustable depth. in the second thread. 7. The argon-filling device for branch tube seat welding according to claim 1, characterized in that, the first end of the argon-filling core tube (1) is provided with a second argon gas inlet (102) for filling in argon gas , the second end is provided with at least one second argon outlet (10) for argon to flow out; The inner surface of the tube wall of the argon-filled core tube (1) is surrounded to form a hollow cavity (101) for the circulation of argon gas. 8. The argon-filling device for branch tube seat welding according to claim 7, characterized in that, the second argon gas outlet (10) is arranged on the tube wall of the second end of the argon-filling core tube (1), so that The end of the tube wall at the second end of the argon-filled core tube (1) is also provided with an argon space barrier for blocking the argon gas flowing out of the second argon gas outlet (10) back to the back of the main tube (12) plate (7), and a fixture for fixing the argon space baffle (7). 9. The welding argon charging device for branch pipe seat according to claim 8, characterized in that, the fixing member includes a nut (4), and cooperates with the nut (4) to clamp the argon space barrier Plate(7) with screws(5). 10. The argon charging device for branch pipe seat welding according to claim 8, characterized in that, the argon space baffle (7) is made of high temperature resistant tape material.