High-precision pipe joint welding method and auxiliary welding device

Abstract

The application discloses a high-precision nozzle mounting and welding method and an auxiliary welding device, and the method comprises the following steps: welding an isolation layer on the outer wall of a body to be welded, drilling a nozzle mounting hole at the position of the isolation layer; manufacturing a bushing according to the inner diameter of the nozzle mounting hole, and preliminarily processing the bottom of the nozzle according to the inner diameter of the bushing, so that the bottom of the nozzle can be inserted into the bushing; welding the bushing in the nozzle mounting hole; inserting the bottom of the nozzle into the bushing, and welding the nozzle and the isolation layer; drilling a nozzle hole at the center position of the nozzle, and the diameter of the nozzle hole is matched with the nozzle mounting hole. The high-precision nozzle mounting and welding method can effectively avoid the welding quality problem of the root of the nozzle, and effectively ensure the mounting and welding size precision of the nozzle.

Description

TECHNICAL FIELD

[0001] The present application relates to a high-precision pipe welding method and an auxiliary welding device, and belongs to the technical field of pressure vessel equipment. BACKGROUND

[0002] Large-scale pressure vessels, heat exchangers and other products for petroleum, chemical industry and nuclear power are provided with small pipes on the outer wall of the equipment cylinder for measuring working pressure, working temperature and water level. The positioning requirements for welding these pipes are relatively high, and the dimensional tolerance and geometric tolerance are strict.

[0003] Especially in the process of manufacturing main equipment in the nuclear island, the technical requirements are more stringent, and the pipe and the pipe mounting hole are required to have high coaxial precision. In addition to the high dimensional accuracy requirement for pipe welding, the pipe welding quality is also required to be higher.

[0004] Due to the influence of cold working precision, welding deformation and other comprehensive factors, the conventional pipe welding process cannot meet the requirements of product pipe welding, resulting in inaccurate installation on the construction site.

[0005] In addition, pressure vessels and heat exchanger products are manufactured horizontally in the manufacturing plant, and the adjustment of the equipment orientation is realized through the assembly and welding of the roller frame. During the manufacturing process, there is a risk of knocking and bruising the pipe on the outer wall of the cylinder. The replacement of the pipe not only needs to ensure the weld quality, but also needs to ensure the dimensional tolerance of the pipe after welding. The existing welding method has a low success rate in pipe replacement and re-welding.

[0006] Due to the above reasons, the present inventors have studied the existing pipe welding method and proposed a pipe welding positioning method with high precision and good welding quality. SUMMARY

[0007] In order to overcome the above problems, the present inventors have conducted in-depth research and designed a high-precision pipe welding method, which comprises the following steps:

[0008] S1, a separation layer 2 is built up on the outer wall of the to-be-welded body 1, and a pipe 4 mounting hole 11 is formed by drilling at the position of the separation layer 2;

[0009] S2, a bushing 3 is made according to the inner diameter of the pipe 4 mounting hole 11, and the bottom of the pipe 4 is preliminarily processed according to the inner diameter of the bushing 3, so that the bottom of the pipe 4 can be inserted into the bushing 3;

[0010] S3, the bushing 3 is welded in the pipe 4 mounting hole 11;

[0011] S4, the bottom of the pipe 4 is inserted into the bushing 3, and the pipe 4 is welded with the separation layer 2;

[0012] S5, a pipe hole 41 is formed at the center position of the pipe 4, and the diameter of the pipe hole 41 matches the pipe mounting hole 11.

[0013] In a preferred embodiment, in S2, the bushing 3 is a cylinder, and the outer diameter of the bushing 3 matches the hole diameter of the nozzle hole 41.

[0014] In a preferred embodiment, the nozzle 4 comprises a main body section 42, a transition section 43 and an insertion section 44, the main body section 42 is a cylinder, and the outer diameter of the main body section 42 is larger than the nozzle hole 41,

[0015] The insertion section 44 is a cylinder, and the outer diameter of the insertion section 44 matches the inner diameter of the bushing 3, and the transition section 43 between the insertion section 44 and the main body section 42 is tapered.

[0016] In a preferred embodiment, in S3, the top end of the bushing 3 is welded to the inner side of the isolation layer 2, so that the bushing 3 is welded in the nozzle mounting hole 11, and after welding, the weld 31 formed is flush with the top end of the isolation layer 2.

[0017] In a preferred embodiment, before welding, the top of the bushing 3 is 2-3 mm away from the top surface of the isolation layer 2,

[0018] In a preferred embodiment, in S4, when welding, there is a gap of 0-2 mm between the top end of the insertion section 44 and the top end of the isolation layer 2.

[0019] In a preferred embodiment, in S5, the hole diameter of the nozzle hole 41 is the same as the hole diameter of the nozzle mounting hole 11, and by punching, the nozzle 4 is penetrated up and down, and the bushing 3 is separated from the isolation layer 2.

[0020] In a preferred embodiment, the method further comprises step S6, weld detection on the welded part.

[0021] The application also provides a high-precision nozzle welding auxiliary welding device for welding a nozzle 4 on a body to be welded 1,

[0022] The body to be welded 1 has an isolation layer 2 on the outer wall, and the nozzle mounting hole 11 is arranged at the position of the isolation layer 2,

[0023] The isolation layer 2 is provided with a cylindrical bushing 3, and the nozzle 4 comprises a nozzle main body section 42, a transition section 43 and an insertion section 44,

[0024] The nozzle main body section 42 is a cylinder, and the outer diameter of the nozzle main body section 42 is larger than the nozzle hole 41,

[0025] The insertion section 44 is a cylinder, and the outer diameter of the insertion section 44 matches the inner diameter of the bushing 3, and the transition section 43 between the insertion section 44 and the nozzle main body section 42 is tapered,

[0026] After welding between the transition section 43 and the isolation layer 2, a hole is punched in the center of the connecting pipe 4, so that the hole diameter is the same as the connecting pipe 4 mounting hole 11.

[0027] In a preferred embodiment, the bushing 3 is welded in the connecting pipe 4 mounting hole 11.

[0028] The present application has the beneficial effects, including:

[0029] (1) The bushing ingeniously solves the problem of connecting pipe welding positioning accuracy;

[0030] (2) The connecting pipe center hole is processed after welding, which can effectively avoid the welding quality problem of the connecting pipe root, and effectively ensure the welding size accuracy of the connecting pipe;

[0031] (3) It not only ensures the product quality, but also improves the efficiency of connecting pipe welding. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The present application has the beneficial effects, including:

[0033] Figure 2 The present application has the beneficial effects, including:

[0034] Figure 3 The present application has the beneficial effects, including:

[0035] Figure 4 The present application has the beneficial effects, including:

[0036] Figure 5 The present application has the beneficial effects, including:

[0037] BRIEF DESCRIPTION OF DRAWINGS

[0038] 1-Body to be welded;

[0039] 2-Isolation layer;

[0040] 3-Bushing;

[0041] 4-Connecting pipe;

[0042] 11-Mounting hole;

[0043] 31-Welding seam;

[0044] 41-Connecting pipe hole;

[0045] 42-Body section;

[0046] 43 - transition section;

[0047] 44 - insertion section. DETAILED DESCRIPTION

[0048] The application will be further described by the accompanying drawings and examples. The features and advantages of the application will become more apparent from the description.

[0049] The term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. The description is not intended to limit the application to the forms shown. Unless otherwise indicated, the drawings are not necessarily drawn to scale.

[0050] According to the high-precision pipe welding method provided by the application, the method comprises the following steps:

[0051] S1, a separation layer 2 is built up on the outer wall of a body to be welded 1, and a pipe mounting hole 11 is formed by drilling at the position of the separation layer 2, as shown in Figure 1 ;

[0052] S2, a bushing 3 is made according to the inner diameter of the pipe mounting hole 11, and the bottom of a pipe 4 is preliminarily processed according to the inner diameter of the bushing 3, so that the bottom of the pipe 4 can be inserted into the bushing 3;

[0053] S3, the bushing 3 is welded in the pipe mounting hole 11;

[0054] S4, the bottom of the pipe 4 is inserted into the bushing 3, and the pipe 4 is welded with the separation layer 2;

[0055] S5, a pipe hole 41 is formed by drilling at the center position of the pipe 4, and the diameter of the pipe hole 41 matches the pipe mounting hole 11.

[0056] In the application, the transition connection between the body to be welded 1 and the pipe 4 is achieved by building up the separation layer 2 on the outer wall of the body to be welded 1 for positioning the bushing 3, so as to improve the positioning accuracy.

[0057] The body to be welded 1 can be a cylinder or an irregularly shaped part, and further preferably, the body to be welded 1 is a cylinder of a pressure vessel, and more preferably, a cylinder of a nuclear power pressure vessel, and the high-precision pipe welding method is used for the pipe welding of the nuclear power pressure vessel.

[0058] In a preferred embodiment, in S1, the pipe welding position line is determined on the outer wall of the body to be welded 1, in order to improve the positioning accuracy of the pipe, a machine tool can be used for auxiliary scribing, and the area for building up the separation layer is determined according to the outer diameter size of the pipe and the size of the weld leg.

[0059] In the present application, the surfacing can adopt manual welding, or can adopt automatic welding or mechanical welding, and no limitation is made thereto.

[0060] In the present application, the surfacing of the isolation layer and then welding can solve the precision problem of the connecting pipe, the center hole machining of the connecting pipe is completed first, then the assembly and welding of the connecting pipe and the body to be welded are carried out, and in the welding process of the connecting pipe, deformation and inclination may occur, which results in low size precision, and after the isolation layer is surfaced, welding is carried out, so that the welding deformation is reduced, and the size precision is improved.

[0061] In addition, the surfacing of the isolation layer and then welding can reduce the machining difficulty of the center hole after the connecting pipe is assembled and welded.

[0062] In a preferred embodiment, after the isolation layer is surfaced, the isolation layer is subjected to flaw detection and magnetic powder detection, so as to effectively verify the surfacing quality of the isolation layer.

[0063] More preferably, before the flaw detection and the magnetic powder detection, the top surface of the isolation layer is polished, so that the top surface of the isolation layer presents a metallic luster, so as to improve the accuracy of the detection result.

[0064] According to a preferred embodiment of the present application, the effective thickness of the isolation layer 2 is greater than or equal to 5 mm, and through a large number of practices, it is found that if the isolation layer is too thin, the base material of the body to be welded 1 is easily affected when the body to be welded 1 and the connecting pipe are welded, and the performance of the base material is reduced.

[0065] According to an embodiment of the present application, in S2, the bushing 3 is a cylinder, as shown in Figure 2 The outer diameter of the bushing 3 matches the hole diameter of the connecting pipe hole 41, and more preferably, the assembly gap between the outer diameter of the bushing 3 and the hole diameter of the connecting pipe hole 41 is 0.02-0.05 mm, so as to ensure the concentricity of the bushing 3 and the installation hole 11 of the connecting pipe.

[0066] In a preferred embodiment, the wall thickness of the bushing 3 is greater than 5 mm, and when the wall thickness is less than 5 mm, there is a risk of deformation when the end of the bushing 3 is welded with the isolation layer, which may cause difficulty in inserting the connecting pipe 4, or the gap between the connecting pipe 4 and the bushing is too large, affecting the assembly precision.

[0067] According to a preferred embodiment of the present application, the surface roughness of the bushing is better than Ra3.2, so as to ensure the assembly gap, and the outer diameter of the bushing is matched with the inner diameter of the hole 11 during processing, the smaller the assembly gap, the more accurate the positioning, and the roughness is too large, which affects the assembly of the bushing and the subsequent removal.

[0068] According to the present application, the connecting pipe 4 comprises a main body section 42, a transition section 43 and an insertion section 44, and the cross section is as shown in Figure 2 The main body section 42 is a cylinder, the outer diameter of the main body section 42 is greater than the connecting pipe hole 41,

[0069] The insertion section 44 is a cylinder with an outer diameter matching the inner diameter of the bushing 3, and a tapered transition section 43 between the insertion section 44 and the main section 42.

[0070] In a preferred embodiment, the fitting clearance between the outer diameter of the insertion section 44 and the inner diameter of the bushing 3 is 0.02-0.05 mm.

[0071] In a preferred embodiment, the insertion depth of the insertion section 44 into the bushing 3 is greater than 50 mm, to ensure the verticality between the adapter 4 and the body to be welded 1.

[0072] In a preferred embodiment, the roughness of the outer surface of the insertion section 44 is better than Ra3.2, to ensure the fitting clearance and improve the equipment accuracy.

[0073] According to the present application, the adapter 4 can be a solid adapter, or a pre-drilled adapter with a center hole, and when the center hole is pre-drilled, the hole diameter is smaller than the outer diameter of the insertion section.

[0074] In S3, the bushing 3 top end is welded to the inner side of the isolation layer 2, so that the bushing 3 is welded in the adapter 4 mounting hole 11, and after welding, the weld 31 formed is flush with the top end of the isolation layer 2, as shown in Figure 3 .

[0075] More preferably, before welding, the top of the bushing 3 is 2-3 mm away from the top surface of the isolation layer 2, to achieve the fixation of the bushing, and if the distance between the top of the bushing 3 and the top surface of the isolation layer 2 is too small, it will cause the weld leg between the bushing and the isolation layer to be too small, and if the distance between the top of the bushing 3 and the top surface of the isolation layer 2 is too large, it will increase the work load of the build-up welding and waste costs.

[0076] According to a preferred embodiment of the present application, in S4, during welding, the top end of the insertion section 44 is 0-2 mm higher than the top end of the isolation layer 2, as shown in Figure 4 , to ensure the welding strength and the uniformity of the clearance welding around.

[0077] In a preferred embodiment, in S4, during welding, the adapter 4 is first fixed between the isolation layer 2 by spot welding, and then the verticality of the adapter relative to the body to be welded 1 is detected, and if there is an inclination, the welding arc starting position is adjusted according to the inclination position, to improve the verticality of the adapter relative to the body to be welded 1.

[0078] According to the present application, in S5, the hole diameter of the adapter hole 41 is the same as the hole diameter of the adapter 4 mounting hole 11, and by punching, the adapter 4 is penetrated up and down, and the bushing 3 is separated from the isolation layer 2, and the bushing is removed, as shown in Figure 5 .

[0079] In the present application, the connecting pipe is welded with the body to be welded first, and then the connecting pipe is punched, which can greatly reduce the deformation degree of the connecting pipe during welding, thereby ensuring the precision and quality after welding.

[0080] Further preferably, the inner wall of the connecting pipe hole 41 is polished to be smooth.

[0081] According to the present application, the method further has a step S6 of detecting the weld joint.

[0082] Preferably, the detection is performed by volume detection and surface detection, both of which are common detection methods for weld joints, and the specific process is not described herein, and the volume detection is preferably ultrasonic detection, and the surface detection is preferably magnetic powder detection.

[0083] According to the present application, the method further includes a replacement process of the connecting pipe, which includes:

[0084] S7, cutting off the original connecting pipe above the isolation layer;

[0085] S8, repeating S2-S5 to complete the connecting pipe welding.

[0086] Preferably, the welding detection is repeated after the welding is completed.

[0087] The present application also provides a high-precision connecting pipe welding auxiliary welding device for welding the connecting pipe 4 on the body to be welded 1,

[0088] The body to be welded 1 has an isolation layer 2 on the outer wall, and the connecting pipe 4 mounting hole 11 is arranged at the position of the isolation layer 2,

[0089] The isolation layer 2 is provided with a sleeve 3 of a cylinder, and the connecting pipe 4 includes a connecting pipe main section 42, a transition section 43 and an insertion section 44,

[0090] The connecting pipe main section 42 is a cylinder, and the outer diameter of the connecting pipe main section 42 is greater than the connecting pipe hole 41,

[0091] The insertion section 44 is a cylinder, and the outer diameter of the insertion section 44 matches the inner diameter of the sleeve 3, and the transition section 43 between the insertion section 44 and the connecting pipe main section 42 is tapered,

[0092] The transition section 43 is welded with the isolation layer 2, and then a hole is punched at the center position of the connecting pipe 4, so that the hole diameter is the same as the connecting pipe 4 mounting hole 11.

[0093] In a preferred embodiment, the sleeve 3 is welded in the connecting pipe 4 mounting hole 11.

[0094] In a preferred embodiment, the outer diameter of the bushing 3 matches the inner diameter of the nozzle hole 41, more preferably, the assembly gap between the outer diameter of the bushing 3 and the inner diameter of the nozzle hole 41 is 0.02-0.05mm.

[0095] In a preferred embodiment, the wall thickness of the bushing 3 is greater than 5mm.

[0096] In a preferred embodiment, the surface roughness of the bushing is better than Ra3.2.

[0097] In a preferred embodiment, the top end of the bushing 3 is welded to the inner side of the isolation layer 2, so that the bushing 3 is welded in the nozzle hole 4 mounting hole 11, and after welding, the weld of the bushing 3 is flush with the top end of the isolation layer 2.

[0098] In a preferred embodiment, the outer diameter of the insertion section 44 matches the inner diameter of the bushing 3, and the assembly gap is 0.02-0.05mm.

[0099] In a preferred embodiment, the depth of the insertion section 44 inserted into the bushing 3 is greater than 50mm.

[0100] In a preferred embodiment, the surface roughness of the outer surface of the insertion section 44 is better than Ra3.2.

[0101] In a preferred embodiment, before welding, the top of the bushing 3 is 2-3mm away from the top surface of the isolation layer 2,

[0102] The gap between the top end of the insertion section 44 and the top end of the isolation layer 2 is 0-2mm.

[0103] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear" and the like indicate the orientation or positional relationship based on the working state of the present application, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", "fourth" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0104] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0105] The application has been described above with reference to preferred embodiments. However, these embodiments are merely exemplary and are intended to be illustrative only. Various substitutions and alterations are possible in view of the disclosure of this application without departing from the spirit and scope of the application.

Claims

1. A high-precision pipe joint welding method, characterized by, The method comprises the following steps: S1, a separation layer (2) is welded on the outer wall of the body (1) to be welded, and the effective thickness of the separation layer (2) is greater than or equal to 5 mm. A hole is drilled in the position of the separation layer (2) to form a mounting hole (11) for the connecting pipe (4); S2, a bushing (3) is made according to the inner diameter of the mounting hole (11) for the connecting pipe (4), and the wall thickness of the bushing (3) is greater than 5 mm. The bottom of the connecting pipe (4) is preliminarily processed according to the inner diameter of the bushing (3) so that the bottom of the connecting pipe (4) can be inserted into the bushing (3); S3, the bushing (3) is welded in the mounting hole (11) for the connecting pipe (4); S4, the bottom of the connecting pipe (4) is inserted into the bushing (3), and the connecting pipe (4) is welded with the separation layer (2); S5, a hole is drilled in the center of the connecting pipe (4) to form a connecting pipe hole (41), and the diameter of the connecting pipe hole (41) matches the diameter of the mounting hole (11) for the connecting pipe; In S5, the diameter of the connecting pipe hole (41) is the same as the diameter of the mounting hole (11) for the connecting pipe (4). By drilling, the connecting pipe (4) penetrates up and down, and the bushing (3) is separated from the separation layer (2).

2. The high-precision connecting pipe welding method according to claim 1, wherein In S2, the bushing (3) is a cylinder, and the outer diameter of the bushing (3) matches the diameter of the connecting pipe hole (41).

3. The high-precision connecting pipe welding method according to claim 1, wherein The connecting pipe (4) comprises a main body section (42), a transition section (43), and an insertion section (44). The main body section (42) is a cylinder, and the outer diameter of the main body section (42) is greater than the connecting pipe hole (41), The insertion section (44) is a cylinder, and the outer diameter of the insertion section (44) matches the inner diameter of the bushing (3). The transition section (43) between the insertion section (44) and the main body section (42) is tapered.

4. The high-precision connecting pipe welding method according to claim 1, wherein In S3, the top end of the bushing (3) is welded with the inner side of the separation layer (2), so that the bushing (3) is welded in the mounting hole (11) for the connecting pipe (4). After welding, the weld (31) is flush with the top end of the separation layer (2).

5. The high-precision connecting pipe welding method according to claim 1, wherein Before welding, the top of the bushing (3) is 2-3 mm away from the top surface of the separation layer (2).

6. The high-precision connecting pipe welding method according to claim 1, wherein In S4, there is a gap of 0-2 mm between the top end of the insertion section (44) and the top end of the separation layer (2) during welding.

7. The high-precision connecting pipe welding method according to claim 1, wherein The method further comprises step S6, weld detection of the welded part.

8. A high-precision connecting pipe welding auxiliary welding device for welding a connecting pipe (4) on a body (1) to be welded according to any one of claims 1-7, wherein The body (1) to be welded has a separation layer (2) on the outer wall, and a mounting hole (11) for the connecting pipe (4) is provided at the position of the separation layer (2), A bushing (3) in the form of a cylinder is provided in the separation layer (2), and the connecting pipe (4) comprises a main body section (42), a transition section (43), and an insertion section (44), The adapter body section (42) is a cylinder, the outer diameter of the adapter body section (42) is larger than the adapter hole (41), The insertion section (44) is a cylinder, the outer diameter of the insertion section (44) matches the inner diameter of the bushing (3), and a tapered transition section (43) is arranged between the insertion section (44) and the adapter body section (42), After welding between the transition section (43) and the isolation layer (2), a hole is punched at the center position of the adapter (4), so that the hole diameter is the same as the adapter (4) mounting hole (11) hole diameter.

9. The high precision adapter welding aid welding apparatus of claim 8, wherein, The bushing (3) is welded in the adapter (4) mounting hole (11).

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