Special-shaped butt joint component welding device and welding method thereof

Abstract

The invention discloses a special-shaped butt joint component welding device and a welding method thereof, and relates to the technical field of special-shaped component welding, the special-shaped butt joint component welding device comprises a clamping unit, the clamping unit comprises a mounting base, a mounting shell arranged on the mounting base and a clamping part arranged on the mounting shell, and the clamping part comprises a rotating assembly arranged on the mounting shell; and a clamping assembly. By arranging the rotating assembly and the clamping assembly, the special-shaped component can be stably fixed on the horizontal plane when being treated, accurate alignment and stability of the component in the welding process are ensured, the welding precision is improved, the special-shaped component rotates at a constant speed in the treatment process, and the welding quality is improved. Compared with the prior art, welding defects caused by local overheating or uneven heating are avoided, the pause time in the welding process is shortened, the welding speed is increased, the whole welding period is shortened, the production efficiency is improved, meanwhile, errors possibly occurring in the manual operation process are reduced, and the labor intensity of operators is also reduced.

Description

Technical Field

[0001] The invention relates to the technical field of welding of special-shaped parts, and in particular to a welding device for special-shaped butt-jointed parts and a welding method thereof. Background Art

[0002] One side is a straight pipe component, and the other side is a valve, tee, elbow, etc., with inconsistent structural dimensions at both ends, especially unequal inner and outer wall dimensions and significant thickness differences. The components formed by welding are widely used in actual engineering. For the components formed by these welded joints with inconsistent structural dimensions at both ends, the national standards and industry standards have certain provisions on how to transition them. However, due to the limitations of manufacturing and processing capabilities or actual production, there are a large number of special-shaped welded joints with sudden changes in knot shape and wall thickness in actual engineering. For these welded joints, the stress concentration position at the component structure change overlaps or is adjacent to the fusion zone of the welded joint. This makes the overlapping or adjacent area the weakest link in the entire component structure. During use, especially under the action of additional system stress, early failure and cracking are prone to occur, resulting in pipeline leakage and safety risks.

[0003] In order to improve the problem that the stress concentration of the structure of the conventional reducer welded joint overlaps with the fusion zone of the welded joint or the distance is too close to form a weak zone, which increases the risk of early failure of the pipeline, the staff often adopts the method of secondary machining of the special-shaped structural section, using a turning tool to turn the surface of the thick end parent material to form a straight section of a certain length (the outer diameter is consistent with the thinner pipe section), and the slope is 15 to 30° to transition to the outer diameter of the thick end, so as to reduce the stress and avoid the overlap of the structural stress and the welding fusion line. However, only turning the original welded joint can only change the appearance of the original welded joint, and cannot solve the problem of internal stress concentration. In addition, the secondary machining of the pipeline pipe fittings equipment site also requires certain spatial structural conditions. However, at the equipment site, due to site limitations, large mechanical tools cannot be used, and when the pipe fittings are manually polished, appropriate cutting cannot be performed evenly around the pipe fittings. Therefore, it is necessary to propose a small-volume welding device and welding method, which is convenient for use at the equipment site, to reduce the stress of the conventional reducer welded joint structure and avoid the overlap of the structural stress and the welding fusion line. Summary of the invention

[0004] In view of the problems existing in the above-mentioned existing welding devices and welding methods for special-shaped butt parts, the present invention is proposed.

[0005] Therefore, the object of the present invention is to provide a welding device for special-shaped butt parts, which aims to solve the technical problem that when manually grinding the pipe fitting, appropriate cutting cannot be performed evenly around the pipe fitting.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: comprising: a clamping unit, comprising a mounting seat, a mounting shell arranged on the mounting seat, and a clamping portion arranged on the mounting shell;

[0007] The clamping units are provided in at least two groups.

[0008] As a preferred solution of the welding device for special-shaped butt-jointed parts of the present invention, the clamping portion includes a rotating assembly arranged on the mounting shell.

[0009] As a preferred solution of the welding device for special-shaped butt-jointed parts of the present invention, the clamping portion further comprises a clamping assembly arranged on the rotating assembly.

[0010] As a preferred solution of the welding device for special-shaped butt-jointed parts of the present invention, the rotating assembly includes a driving gear arranged on the surface of the mounting shell, and a driven gear meshed with the surface of the driving gear.

[0011] As a preferred solution of the welding device for special-shaped butt-jointed parts of the present invention, the rotating assembly further includes a limiting ring arranged on the driven gear.

[0012] As a preferred solution of the welding device for special-shaped butt parts described in the present invention, the clamping assembly includes an adjustment ring arranged on the limiting ring, a fixing block arranged on the adjustment ring, and a clamping ring arranged on a side of the fixing block away from the adjustment ring.

[0013] As a preferred solution of the welding device for special-shaped butt joint parts of the present invention, there are at least three groups of adjustment rings, and grooves corresponding to the fixing blocks are formed on the adjustment rings.

[0014] The beneficial effects of the present invention are as follows: by arranging a rotating assembly and a clamping assembly, special-shaped parts can be stably fixed on a horizontal plane when being processed, ensuring accurate alignment and stability of the parts during welding and improving welding accuracy; by rotating the special-shaped parts at a constant speed during processing, the welding heat source can be evenly applied to the welding area, which helps to achieve uniform formation of the weld, avoid welding defects caused by local overheating or uneven heating, reduce the pause time during welding, increase the welding speed, thereby shortening the entire welding cycle and improving production efficiency, while reducing possible errors that may occur during manual operation and reducing the labor intensity of the operator.

[0015] Another object of the present invention is to provide a welding method for a welding device of special-shaped butt-jointed parts, the purpose of which is to solve the technical problem that merely turning the original welded joint can only change the appearance of the original welded joint but cannot solve the internal stress concentration.

[0016] In order to solve the above technical problems, the present invention provides the following technical solutions: comprising a welding device for special-shaped butt-jointed parts, the method comprising:

[0017] The ports of the special-shaped parts are respectively fixed by the clamping units, the surface of the welded joint is measured, and the excess height of the original welded joint is cut off;

[0018] A smooth transition zone is polished on the surface of the original weld joint and the original slope section, and a widening zone and a surfacing zone are set around the straight pipe section and the slope section, so that the angle of the diagonal line connecting the straight pipe section and the slope section is 15 to 30 degrees;

[0019] Preheat the cladding area before welding, and use welding rods to perform multi-layer and multi-pass thin-layer welding on the weld;

[0020] During welding, the driving gear is turned on to drive the driven gear and the special-shaped component to rotate;

[0021] After welding, the weld surface is cleaned and special-shaped parts are subjected to post-weld heat treatment and shaping treatment.

[0022] As a preferred solution of the welding method of the welding device for special-shaped butt parts of the present invention, the ratio of the weld length corresponding to each group of welding rods to the melting length is greater than 50%.

[0023] The beneficial effects of the present invention are as follows: by setting the widening area and the surfacing area, and controlling the angle between the straight pipe section and the slope section, it helps to improve the stress distribution of the welded joint, reduce welding stress and deformation, and multi-layer and multi-pass welding helps to control the heat input in the welding process, reduce welding deformation, and at the same time improve the density and uniformity of the weld, thereby ensuring the accuracy and welding quality of the welding process and achieving a significant reduction in the structural stress of special-shaped butt-jointed components. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0025] Figure 1 It is a schematic diagram of the overall structure of the clamping unit of the present invention in working state.

[0026] Figure 2 It is a schematic diagram of the overall structure of the clamping unit of the present invention.

[0027] Figure 3 It is a schematic diagram of the structure of the clamping assembly of the present invention.

[0028] Figure 4It is a schematic diagram of the overall structure before welding repair of the present invention.

[0029] Figure 5 It is a schematic diagram of the widening area in the welding repair of the present invention.

[0030] Figure 6 It is a schematic diagram of the overall structure after welding repair of the present invention.

[0031] Figure 7 for Figure 6 Enlarged schematic diagram at point A in the middle. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0034] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0035] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0036] The present invention tests the stress concentration degree of the welded joint with reference to "Evaluation of Stress Concentration of 45 Steel Based on Magnetic Memory Detection Method".

[0037] Example 1

[0038] Reference Figure 1-2 , which is the first embodiment of the present invention, provides a welding device for special-shaped butt parts, the device comprising:

[0039] The clamping unit 100 includes a mounting seat 101, a mounting shell 102 disposed on the mounting seat 101, and a clamping portion 103 disposed on the mounting shell 102;

[0040] At least two groups of clamping units 100 are provided, and both ends of the special-shaped component are clamped in the clamping units 100 respectively, which can ensure the precise alignment and stability of the components during the welding process and improve the welding accuracy.

[0041] Among them, the clamping part 103 includes a rotating component 103a arranged on the mounting shell 102, and a clamping component 103b arranged on the rotating component 103a. The rotating component 103a allows the special-shaped component clamped in the clamping component 103b to rotate at a uniform speed around the center point of the clamping unit 100, ensuring that the position of the component will not shift during the welding process, thereby improving the accuracy and consistency of welding, while reducing the pause time during the welding process and increasing the welding speed.

[0042] During use, the two ends of the special-shaped component that needs to be repaired are respectively fixed on the clamping assembly 103b. At this time, the special-shaped component is in a horizontal state as a whole. When it is processed, the special-shaped component is driven to rotate by the rotating assembly 103a, which is convenient for the operator to conduct an overall inspection of the special-shaped component and reduces the operator's work intensity. When the special-shaped component is processed, the special-shaped component can be taken out from the clamping unit 100.

[0043] Example 2

[0044] Reference Figure 1-3 , which is the second embodiment of the present invention. This embodiment is different from the first embodiment in that: the rotating assembly 103a includes a driving gear 103a-1 arranged on the surface of the mounting shell 102, a driven gear 103a-2 meshing with the surface of the driving gear 103a-1, and a limiting ring 103a-3 arranged on the driven gear 103a-2. When processing the special-shaped parts, the driving gear 103a-1 is opened to drive the driven gear 103a-2 and the limiting ring 103a-3 to rotate.

[0045] Compared with Example 1, further, the clamping assembly 103b includes an adjustment ring 103b-1 arranged on the limiting ring 103a-3, a fixed block 103b-2 arranged on the adjustment ring 103b-1, and a clamping ring 103b-3 arranged on a side of the fixed block 103b-2 away from the adjustment ring 103b-1. By adjusting the adjustment ring 103b-1 and the fixed block 103b-2, the diameter of the adjustment ring 103b-1 is changed so that it can adapt to clamping rings 103b-3 of different sizes, and the fixed block 103b-2 is fixed between the adjustment ring 103b-1 and the clamping ring 103b-3, thereby improving the stability of the clamping ring 103b-3 in clamping the special-shaped component, and in the process of adjusting the adjustment ring 103b-1 and the fixed block 103b-2, the adjustment ring 103b-1 always presents a circle, ensuring that the central axis of the special-shaped component is always on the same horizontal plane;

[0046] Preferably, the fixing method of the fixing block 103b-2 includes bolt fixing or thread fixing;

[0047] At least three groups of adjustment rings 103b-1 are provided, which increase the fineness and flexibility of adjustment and can more accurately adapt to special-shaped parts of different sizes. A groove corresponding to the fixed block 103b-2 is opened on the adjustment ring 103b-1, which improves the stability of the fixed block 103b-2, and the groove is toward the center of the rotation axis. During the rotation process, the centripetal force always applies a force to close the fixed block 103b-2 to avoid the fixed block 103b-2 from detaching from the adjustment ring 103b-1 during the rotation process, which poses a safety hazard. It is also convenient to remove the fixed block 103b-2. When it is necessary to replace special-shaped parts of different specifications, the fixed block 103b-2 can be manually detached from the adjustment ring 103b-1 through the groove of the fixed block 103b-2. This semi-automatic adjustment mechanism reduces the errors that may occur during manual adjustment and improves the reliability of the welding process.

[0048] The remaining structures are the same as those of Example 1.

[0049] Example 3

[0050] Reference Figure 1-7 , which is the third embodiment of the present invention, is based on embodiments 1-2 and provides a welding method for a special-shaped butt-jointed component welding device, comprising:

[0051] The ports of the special-shaped parts are fixed by the clamping units 100 respectively, which ensures the accurate positioning and stability before welding. The surface of the welded joint is measured, and the excess height of the original welded joint is cut off to ensure the flatness and quality of the welded joint.

[0052] Grinding a smooth transition zone S on the surface of the original weld joint and the original slope section N helps to reduce stress concentration and improve the strength and durability of the weld joint. A widening zone K and a surfacing zone Q are set around the straight pipe section M and the slope section N, so that the angle a of the oblique line connecting the straight pipe section M and the slope section N is 15 to 30 degrees, thereby optimizing the geometric structure of the weld joint and reducing welding stress.

[0053] Preheat the cladding area Q before welding, use welding rods to perform multi-layer and multi-pass thin-layer welding on the weld, reduce the heat-affected zone during welding, control the heat input during welding, reduce welding deformation, improve the toughness and overall performance of the welded joint, and at the same time improve the density and uniformity of the weld;

[0054] During welding, the driving gear 103a-1 is turned on to drive the driven gear 103a-2 and the special-shaped component to rotate, thereby achieving a continuous and uniform welding process;

[0055] After welding, the weld surface is cleaned, and special-shaped parts are subjected to post-weld heat treatment and shaping treatment to further improve the quality and performance of the welded joint.

[0056] Compared with Example 2, further, the corners of the smooth transition zone S are R3 to R10, which reduces stress concentration and improves the fatigue strength of the welded joint and the stability of the overall structure.

[0057] Compared with Example 2, further, the widened area K is a base material area where the straight pipe section M is 5 to 10 mm wider than the groove, and the slope section N is 5 to 10 mm wider than the upper edge of the slope, which optimizes the heat distribution and the distribution of the filler metal during welding and reduces welding deformation.

[0058] Compared with Example 2, further, the surfacing area Q is composed of two widened areas K, the original weld joint area and the base material area of ​​the slope section N. The expanded surfacing area Q may increase the volume and strength of the weld joint, help to withstand greater loads and improve the durability of the weld joint.

[0059] Compared with Example 2, further, preheating before welding is to heat the special-shaped component to 200-250° C. and then keep it warm for 1-2 hours;

[0060] Among them, the width of the heating side is ≥ 4 times the pipe wall thickness;

[0061] The thickness of a single layer of welding is ≤3mm;

[0062] Each layer of welding joint is offset by 10 to 15 mm in the horizontal plane to achieve a more uniform welding thermal cycle and better weld formation, reduce thermal stress and heat-affected zone during welding, improve the toughness and uniformity of the welding joint, and the refined parameters help to control the welding process more accurately.

[0063] Compared with Example 2, further, the ratio of the weld length corresponding to each group of welding rods to the melting length is greater than 50%, thereby reducing material waste and improving welding efficiency.

[0064] The remaining structure is the same as that of Example 2.

[0065] Example 4

[0066] This example is used to explore the effects of different corners and surfacing areas on the performance of the repaired welded joint.

[0067] The specific experimental method is:

[0068] 1) Measure the surface of the component welding joint to understand the groove structure and width of the welding joint, the diameter and thickness of the straight pipes and special-shaped parts on both sides of the welding joint, and the inclination angle and length of the slope section;

[0069] 2) Refer to the relevant standard regulations to formulate corresponding welding process parameters and heat treatment process parameters;

[0070] 3) All the excess height of the original welded joint is turned off, the surface is kept flat, and it is manually polished along the original slope section so that the angle a of the oblique line connecting the straight pipe section and the slope section is 15-30°. The polishing range is increased by 10mm of base material at both ends of the original area as a widening area. After rust removal and decontamination, the original welded joint surface and the original slope section are polished to form a smooth transition zone of R5. The upper edge of the slope is also polished to form a smooth transition zone of R5;

[0071] 4) The surfacing area formed by the two widened areas, the original weld joint area and the base material area of ​​the slope section is welded. The thickness of a single weld layer is 3 mm, and each weld joint is offset by 10 mm on the horizontal plane.

[0072] Taking the 10% Cr martensitic heat-resistant steel material commonly used in high-temperature and high-pressure pipelines in thermal power plants as an example, the specific welding process is shown in Tables 1 and 2, and the original welded joint strength is 325 MPa.

[0073] Table 1 Welding process parameters

[0074]

[0075] Table 2 Post-weld heat treatment process parameters

[0076]

[0077] Keeping other conditions unchanged and changing the corner of the smoothness zone, the performance tests of the welded joints before and after repair were carried out. The results are shown in Table 3.

[0078] Table 3

[0079]

[0080]

[0081] According to Table 3, under the R5 condition, the comprehensive performance of the welded joint is the best. The strength of the repaired welded joint is increased by 58.46%, and the welding deformation and stress concentration are relatively small. This is because the R5 corner provides the best stress distribution and thermal cycle conditions, thereby achieving the best welded joint performance. When the corner of the smooth transition zone is too small, it will lead to uneven stress distribution, thereby increasing stress concentration and affecting the strength and stability of the welded joint. When the corner of the smooth transition zone is further increased to R10, the improvement rate of the welded joint strength decreases slightly. This is because an overly large corner may cause some areas of the welded joint to fail to receive sufficient heat treatment or material flow.

[0082] With other conditions kept unchanged, the added base material areas at both ends of the original area were changed, and the performance tests of the welded joints before and after repair were carried out. The results are shown in Table 4.

[0083] Table 4

[0084]

[0085] It can be seen from Table 4 that as the widening area and the surfacing area increase the base material area, the strength of the welded joint shows an overall upward trend. This is because the increased base material area provides more material to bear the load, thereby improving the overall strength of the welded joint, and helps to distribute heat more evenly during the welding process, reducing deformation caused by thermal expansion and contraction. When the increased base material area at both ends is 10 mm, the comprehensive performance of the welded joint is optimal. When this width is exceeded, the performance improvement effect decreases. This is because an overly wide base material area will reduce the thermal cycle efficiency during welding, and the microstructure of the welded joint may change, such as grain growth, which will reduce the strength and toughness of the material, and will also lead to uneven distribution of residual stress, because the cooling rates of different areas during welding may be different, thus affecting the overall performance of the welded joint.

[0086] In summary, when welding and repairing special-shaped parts made of 10% Cr martensitic heat-resistant steel, the repair effect is best when the R5 condition is set, the straight pipe section is 10mm wider than the groove of the base material area, and the slope section is 10mm wider than the upper edge of the slope. The base material area, the strength of the welded joint can be increased by 58.46, with minimal stress concentration, effectively realizing efficient and high-quality welding of special-shaped butt parts, while ensuring the mechanical properties and durability of the welded joint.

[0087] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, improvements, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0088] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0089] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A welding device for special-shaped butt joint parts, characterized in that: include, A clamping unit (100) comprises a mounting seat (101), a mounting shell (102) arranged on the mounting seat (101), and a clamping portion (103) arranged on the mounting shell (102); The clamping units (100) are provided in at least two groups.

2. The welding device for special-shaped butt joint parts according to claim 1, characterized in that: The clamping portion (103) comprises a rotating assembly (103a) arranged on the mounting shell (102).

3. The welding device for special-shaped butt joint parts according to claim 2, characterized in that: The clamping portion (103) further comprises a clamping component (103b) arranged on the rotating component (103a).

4. The welding device for special-shaped butt joint parts according to claim 3, characterized in that: The rotating assembly (103a) comprises a driving gear (103a-1) arranged on the surface of the mounting shell (102), and a driven gear (103a-2) meshed with the surface of the driving gear (103a-1).

5. The welding device for special-shaped butt joint parts according to claim 4, characterized in that: The rotating assembly (103a) further comprises a limiting ring (103a-3) arranged on the driven gear (103a-2).

6. The welding device for special-shaped butt joint parts according to claim 5, characterized in that: The clamping assembly (103b) comprises an adjustment ring (103b-1) arranged on the limiting ring (103a-3), a fixing block (103b-2) arranged on the adjustment ring (103b-1), and a clamping ring (103b-3) arranged on a side of the fixing block (103b-2) away from the adjustment ring (103b-1).

7. The welding device for special-shaped butt joint parts according to claim 6, characterized in that: At least three groups of the adjustment rings (103b-1) are provided, and grooves corresponding to the fixing blocks (103b-2) are formed on the adjustment rings (103b-1).

8. A welding method for a special-shaped butt-jointed component welding device, characterized in that: The method comprises the device for welding special-shaped butt parts according to claim 7, and comprising: The ports of the special-shaped parts are respectively fixed by the clamping units (100), the surface of the welded joint is measured, and the excess height of the original welded joint is cut off; A smooth transition zone (S) is polished on the surface of the original weld joint and the original slope section (N), and a widening zone (K) and a surfacing zone (Q) are set around the straight pipe section (M) and the slope section (N), so that the angle a of the oblique line connecting the straight pipe section (M) and the slope section (N) is 15 to 30°; Preheating the cladding area (Q) before welding, and performing multi-layer and multi-pass thin-layer welding on the weld using welding rods; During welding, the driving gear (103a-1) is opened to drive the driven gear (103a-2) and the special-shaped component to rotate; After welding, the weld surface is cleaned and special-shaped parts are subjected to post-weld heat treatment and shaping treatment.

9. The welding method of the special-shaped butt-jointed component welding device according to claim 8, characterized in that: The ratio of the weld length to the melting length corresponding to each group of welding rods is greater than 50%.

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