Device and method for controlling welding deformation of titanium alloy

Abstract

The invention relates to the technical field of titanium alloy welding deformation control, in particular to a device and method for controlling titanium alloy welding deformation, and the method comprises the following specific steps: S1, preparation before welding: determining a reversible deformation device according to a welding seam form of a titanium alloy part, and carrying out assembly and spot welding; the assembled titanium alloy welding part is fixed to a reversible deformation device, and it is ensured that the part does not deform in the welding process; s2, a welding process; a thermocouple is placed on the surface of a weld joint, a local heating belt and heat preservation cotton are laid, and the heating belt, the thermocouple and local heating control equipment are connected for heat treatment; and S4, measurement of welding deformation is carried out. According to the method, a complete and easy-to-operate technological process is constructed by combining pre-welding anti-deformation tool fixing and post-welding local heating treatment technologies, and the problem of welding deformation with considerable numerical values and complex forms generated by multiple welding procedures of a large complex titanium alloy structure is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of titanium alloy welding deformation control, and particularly relates to a device and method for controlling titanium alloy welding deformation. Background Art

[0002] Titanium and titanium alloys have the characteristics of high specific strength, corrosion resistance, and non-magnetism, and are widely used in fields such as ships and ocean engineering, and are known as "marine metals". With the continuous increase in China's demand for deep-sea equipment, the demand for titanium alloy pressure hulls with excellent comprehensive performance is becoming more urgent, and the application of various large-thickness and large-size components is gradually increasing. Welding is an essential means for titanium alloy pressure hulls and large components. Processes such as melting, solidification, cooling shrinkage of weld metal, and internal metallographic changes will cause relatively high stresses. At the same time, due to the small elastic modulus of titanium alloys, the deformation caused by welding stress is large. Due to the high specific strength of titanium alloys, when the wall thickness of titanium alloy components is relatively thin, due to its small rigidity and poor stability, welding instability deformation is likely to occur. Especially for large and complex titanium alloy structures, the cross-influence of multiple welding processes makes the structure produce more significant numerical and more complex forms of welding deformation, seriously affecting the dimensional accuracy and stability of titanium alloy structural parts. Therefore, it is necessary to reduce the influence of deformation on the overall structure size. The commonly used means in the prior art to reduce the influence of welding deformation are mainly to reserve deformation amounts and use anti-deformation tooling. After welding, the workpiece and the anti-deformation tooling are placed in a heat treatment furnace for heat treatment, and then the welding deformation is controlled by machining the reserved deformation amount. As the size of titanium alloy workpieces continues to increase, the difficulty of overall heat treatment is also increasing. More often, the method of increasing the deformation amount + machining is used to meet the accuracy requirements of titanium alloy workpieces, resulting in problems such as high construction costs, long cycles, and uncontrollable accuracy.

[0003] Publication No.: CN111774692A, a large cladding nickel-based surfacing process for a cylinder body, includes welding external tooling hoops at both ends of the cylinder body and performing heat treatment on the transition layer after welding, which can effectively control the welding deformation of the surfacing of the container cylinder body. This solution enhances the structural rigidity by welding external tooling hoops at both ends of the cylinder body and optimizes the microstructure of the transition layer by heat treatment under specific parameters to reduce welding stress, thereby effectively controlling welding deformation. However, for large and complex titanium alloy structures, the problem of cross-influence of multiple welding processes cannot solve the problem of more significant numerical and more complex forms of welding deformation generated by the structure.

[0004] Therefore, there is an urgent need to propose a new device and method for controlling titanium alloy welding deformation to solve the problem of significant numerical and complex forms of welding deformation generated by multiple welding processes of large and complex titanium alloy structures. Summary of the Invention

[0005] In view of this, the present invention aims to provide a device and method for controlling the welding deformation of titanium alloys, so as to solve the problem of significant and complex welding deformation generated in the multi-pass welding process of large and complex titanium alloy structures.

[0006] The technical solution of the present invention is realized as follows:

[0007] An object of the present invention is to disclose a device for controlling the welding deformation of titanium alloys. The anti-deformation device includes a first anti-deformation device and a second anti-deformation device. The first anti-deformation device and the second anti-deformation device are respectively arranged on the inner and outer sides of the cylinder. The first anti-deformation device and the second anti-deformation device are provided with an adjusting device, and the adjusting device is used to adjust the deformation amount of the first anti-deformation device and the second anti-deformation device according to the shape of the titanium alloy structural part.

[0008] Further, the first anti-deformation device and the second anti-deformation device have the same structure, and the inner diameter of the first anti-deformation device is smaller than the inner diameter of the second anti-deformation device.

[0009] Further, when the weld form is a butt weld, the first anti-deformation device is a clamp structure, including a strip-shaped body and the adjusting device. The adjusting device is connected to both ends of the strip-shaped body, and the adjusting device adjusts the distance between both ends of the strip-shaped body by tightening and loosening bolts to realize the change of the deformation amount of the first anti-deformation device.

[0010] Further, when the weld form is a fillet weld, the first anti-deformation device includes a pressing plate, a cushion block, a base and an adjusting device.

[0011] The pressing plate is an annular structure with a notch. The pressing plate has two mutually perpendicular sides for restricting the displacement of the flange.

[0012] The cushion block is arranged between the pressing plate and the base, and is used to adjust the distance between the pressing plate and the base to adapt to the fixation of flanges with different thicknesses.

[0013] The base is provided with a plurality of parallel strip-shaped grooves, and the base is used to support the welded part and fix the pressing plate.

[0014] The adjusting device includes a connecting bolt and a second connecting groove. A plurality of the second connecting grooves are evenly arranged on the side of the pressing plate away from the flange. The second connecting groove is an open groove, and the connecting bolt is used to connect the second connecting groove with the strip-shaped grooves at different positions to change the deformation amount of the pressing plate.

[0015] Another object of the present invention is to disclose a method for controlling the welding deformation of titanium alloys. Based on any one of the above-mentioned devices for controlling the welding deformation of titanium alloys, the specific steps are as follows:

[0016] S1: Preparation before welding: Determine the anti-deformation device according to the weld form of the titanium alloy component, assemble and spot-weld, fix the assembled titanium alloy welded component on the anti-deformation device to ensure that the component does not deform during welding;

[0017] S2: Welding process: Weld the titanium alloy component fixed on the anti-deformation device;

[0018] S3: Post-weld treatment: Place thermocouples on the weld surface, lay local heating tapes and heat insulation cotton, and connect the heating tapes and thermocouples to local heating control equipment for heat treatment;

[0019] S4: Measure the welding deformation to verify the control effect.

[0020] Further, in step S1, fix the upper anti-deformation tooling at 150 mm and 1000 mm away from the weld.

[0021] Further, in step S3, place thermocouples on the inner and outer surfaces of the weld, lay local heating tapes and heat insulation cotton, and the center of the weld is at the center of the local heating tape.

[0022] Further, in step S3, the heating rate, heating temperature, heating width, and heat preservation time of the heat treatment are selected according to the grade and thickness t of the titanium alloy component. The heating width ≥ 3t, the heating rate is 200 - 400 °C / h, the heating temperature is 500 - 800 °C, and the heat preservation time is 1 h - 3 h.

[0023] Further, in step S3, the titanium alloy component is cooled to below 100 °C after heating.

[0024] Compared with the prior art, a device and method for controlling titanium alloy welding deformation of the present invention have the following advantages:

[0025] 1. The present invention combines the pre-weld anti-deformation tooling fixation and post-weld local heating treatment technologies to construct a complete and easy-to-operate process flow, including pre-weld preparation, welding fixation, and post-weld local heating and cooling steps. It not only simplifies the process flow but also improves the consistency of welding quality and dimensional accuracy, solves the problem of significant and complex welding deformation generated by multiple welding processes of large and complex titanium alloy structures, meets the high-efficiency and precise production requirements of titanium alloy structural parts, and improves the economy and practicality of the overall process.

[0026] 2. By adopting the anti-deformation tooling, the present invention fixes the titanium alloy component before welding, can effectively counter the deformation problems that may occur during welding, solves the problem of significant and complex welding deformation generated by multiple welding processes of large and complex titanium alloy structures, greatly reduces the test requirements and manufacturing cycle, and reduces the production cost.

[0027] 3. By precisely controlling parameters such as the heating rate, heating temperature, and heat preservation time, the present invention ensures uniform heating of the weld seam, reduces the residual stress of the welded joint, and provides a scientific basis and technical support for titanium alloy materials in the fields of ships, petrochemicals, offshore engineering, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0029] Figure 1 It is a top view after the installation of the anti-deformation device in Embodiment 1;

[0030] Figure 2 It is a front view of the anti-deformation device in Embodiment 1;

[0031] Figure 3 It is a left view of the anti-deformation device in Embodiment 1;

[0032] Figure 4 It is a sectional view taken along line A-A of the anti-deformation device in Embodiment 1;

[0033] Figure 5 It is a sectional view taken along line B-B of the anti-deformation device in Embodiment 1;

[0034] Figure 6 It is a schematic diagram of local heating in Embodiment 1;

[0035] Figure 7 It is a top view after the installation of the anti-deformation device in Embodiment 2;

[0036] Figure 8 It is a front view after the installation of the anti-deformation device in Embodiment 2;

[0037] Figure 9 It is a left view after the installation of the anti-deformation device in Embodiment 2;

[0038] Figure 10 It is a sectional view taken along line A-A of the anti-deformation device in Embodiment 2;

[0039] Figure 11 It is a sectional view taken along line B-B of the anti-deformation device in Embodiment 2.

[0040] REFERENCE MARKS:

[0041] 1, cylinder body; 2, first anti-deformation device; 201, pressing plate; 202, cushion block; 203, platform; 204, strip groove; 3, second anti-deformation device; 4, adjusting device; 401, first connection hole; 402, connecting bolt; 403, second connection groove; 5, flange. Detailed implementation mode

[0042] In order to make the technical means, objectives and effects of the present invention easy to understand, the embodiments of the present invention will be described in detail below with reference to specific illustrations.

[0043] It should be noted that all terms indicating directionality and positional indication in the present invention, such as: "up", "down", "left", "right", "front", "rear", "vertical", "horizontal", "inner", "outer", "top", "bottom", "lateral", "longitudinal", "center", etc., are only used to explain the relative positional relationship and connection situation between components in a specific state, and are only for the convenience of describing the present invention, rather than requiring the present invention to be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, the descriptions involving "first", "second", etc. in the present invention are only for descriptive purposes, and cannot be construed as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features.

[0044] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0045] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0046] An object of the present invention is to disclose a device for controlling the welding deformation of titanium alloy, including a first anti-deformation device 2 and a second anti-deformation device 3 arranged on the inner and outer sides of the cylinder body 1, and an adjusting device 4 is provided on the first anti-deformation device 2 and the second anti-deformation device 3. The adjusting device 4 is used to adjust the deformation amount according to the shape of the titanium alloy structural part.

[0047] The first anti-deformation device 2 and the second anti-deformation device 3 work together to provide rigid support from the inside and outside of the titanium alloy cylinder 1, forming a two-way binding force to prevent bending, angular deformation or instability caused by uneven heat input during welding. The adjusting device 4 can be adaptively adjusted according to the specific shapes of different titanium alloy structural parts, such as curvature, diameter change, thickness difference, etc., and preset a reasonable amount of anti-deformation to offset the shrinkage or warping that may occur after welding; by finely adjusting the position and angle of the anti-deformation device through the adjusting device 4, it can ensure that the titanium alloy components are in an ideal spatial position before welding, reduce the workload of post-weld correction, and improve the overall assembly quality.

[0048] This setting applies prestress through the bilateral anti-deformation devices and, combined with the precise control of the adjusting device 4, significantly reduces the welding residual stress and deformation amount, improves the dimensional stability and mechanical properties of the welded joint. The device structure is reasonable, and the adjusting device 4 is easy to operate. It can be quickly adjusted according to different working conditions, suitable for batch production and customized manufacturing of complex structures, reducing post-weld correction, grinding, repair and other work, shortening the manufacturing cycle, reducing labor and material losses, and improving the overall production efficiency.

[0049] Specifically, the first anti-deformation device 2 and the second anti-deformation device 3 have the same structure, and the inner diameter of the first anti-deformation device 2 is smaller than the inner diameter of the second anti-deformation device 3.

[0050] Due to the different geometric shapes and stress distributions inside and outside the titanium alloy cylinder 1, using the first anti-deformation device 2 and the second anti-deformation device 3 with different inner diameters can better adapt to this difference and provide more effective support. By precisely matching the inner and outer dimensions of the cylinder 1, it ensures that the anti-deformation device can stably fix the cylinder 1 during welding and prevent displacement or deformation caused by welding heat input.

[0051] This setting can better adapt to the different constraint requirements inside and outside the titanium alloy cylinder 1, provide more effective support, reduce welding deformation, and improve welding quality and production efficiency.

[0052] Specifically, when the weld form is a butt weld, the first anti-deformation device 2 is a clamp structure, including a strip-shaped body and an adjusting device 4. The adjusting device 4 is connected to both ends of the strip-shaped body, and the adjusting device 4 adjusts the distance between both ends of the strip-shaped body by tightening and loosening bolts to achieve a change in the deformation amount of the first anti-deformation device 2.

[0053] The first anti-deformation device 2 of the clamp structure can change the distance between both ends of the strip-shaped body through the adjusting device 4, and can adapt to titanium alloy cylinders 1 with various diameter specifications, meeting the clamping and deformation control requirements of workpieces with different sizes. Before welding, a certain pre-tightening force is generated on the clamp by loosening or tightening the bolts, and the closing degree of the clamp is adjusted as needed to apply a reverse deformation amount to the cylinder 1 in advance, so as to offset the shrinkage deformation caused by thermal expansion and contraction after welding cooling. The clamp structure is simple and the operation is convenient, and the installation and removal of the device can be quickly completed manually or with tools.

[0054] This setting has a simple structure and low cost, can adapt to titanium alloy cylinders 1 with different diameters, does not require replacing the main body of the equipment, improves the versatility of the device, is applicable to various butt weld forms and structural dimensions, is quick to disassemble and assemble, intuitive to adjust, has a low threshold for worker training, can quickly be put into the production process, and improves the welding preparation efficiency.

[0055] Preferably, protrusions are arranged radially at both ends of the strip-shaped body, facilitating the installation and fixation of the adjusting device 4.

[0056] Preferably, the adjusting device 4 includes a first connection hole 401 and a connection bolt 402. The two first connection holes 401 are respectively arranged at the protrusions at both ends of the strip-shaped body, and the connection bolt 402 passes through the first connection hole 401 to adjust the deformation amount of the strip-shaped body.

[0057] Specifically, when the weld form is a fillet weld, the first anti-deformation device 2 includes a pressing plate 201, a cushion block 202, a platform 203 and an adjusting device 4.

[0058] The pressing plate 201 is an annular structure with a notch. The pressing plate 201 has two mutually perpendicular sides for restricting the displacement of the flange 5.

[0059] The cushion block 202 is arranged between the pressing plate 201 and the platform 203 for adjusting the distance between the pressing plate 201 and the platform 203 to adapt to the fixation of flanges 5 with different thicknesses.

[0060] The platform 203 is provided with a plurality of parallel strip-shaped grooves 204. The platform 203 is used to support the welded parts and fix the pressing plate 201.

[0061] The adjusting device 4 includes a connection bolt 402 and a second connection groove 403. A plurality of second connection grooves 403 are uniformly arranged on the side of the pressing plate 201 away from the flange 5. The second connection groove 403 is an open groove, and the connection bolt 402 is used to connect the second connection groove 403 with strip-shaped grooves 204 at different positions to change the deformation amount of the pressing plate 201.

[0062] The pressing plate 201 has two mutually perpendicular sides, which are respectively attached to the end face of the flange 5 and parallel to the axis direction of the cylinder 1. By applying pressure, it prevents the flange 5 from shifting or warping during the welding process. By replacing the spacers 202 with different thicknesses, the distance between the pressing plate 201 and the base 203 can be flexibly adjusted, so as to adapt to the flange 5 structures with different thicknesses, without the need to separately design a pressing tool for each type of flange 5, reducing the manufacturing cost. The second connecting groove 403 allows the connecting bolt 402 to move within a certain range, facilitating fine adjustment according to the position of the flange 5. The connecting bolt 402 passes through the pressing plate 201 and is fixed on the base 203, realizing the overall pressing of the pressing plate 201 and the flange 5. The base 203 serves as the basic platform of the entire device, used to carry the titanium alloy cylinder 1 and the flange 5 assembly. By fixing the pressing plate 201 at different positions of the strip-shaped grooves 204 on it through the connecting bolt 402, the deformation amount of the pressing plate 201 is different to adapt to the welding requirements, forming a complete reverse deformation system to ensure the structural stability during the welding process.

[0063] Before welding, this setting applies a pre-tightening force to the flange 5 through the pressing plate 201, the spacer 202, the base 203 and the adjusting device 4 to form a rigid constraint, preventing the flange 5 from warping, angular deformation or misalignment after the welding heat input. With the design of the replaceable spacer 202 and the pressing plate 201 with the second connecting groove 403, it can quickly adapt to the flange 5 structures with different thicknesses and sizes, improving the versatility of the device. Through the rigid connection between the pressing plate 201 and the base 203, it ensures that the relative position between the flange 5 and the cylinder 1 does not change during the welding process, improving the geometric accuracy of the welded joint.

[0064] Specifically, when the weld is a fillet weld, the first reverse deformation device 2 and the second reverse deformation device 3 are respectively arranged inside and outside the cylinder 1. The first reverse deformation device 2 and the second reverse deformation device 3 are arranged adjacent to the fillet weld. The pressing plate 201 is a notched annular structure. The pressing plate 201 can adjust the magnitude of the deformation amount according to the welding requirements, and the change of its deformation amount is realized by the adjusting device 4. In this embodiment, the adjusting device 4 realizes the change of the deformation amount of the pressing plate 201 by connecting the second connecting groove 403 with different strip-shaped grooves 204 on the base 203 through the connecting bolt 402.

[0065] Another object of the present invention is to disclose a method for controlling the welding deformation of titanium alloy, including the following specific steps:

[0066] S1: Preparation before welding: Determine the reverse deformation device according to the weld form of the titanium alloy component, and perform assembly and tack welding. Fix the assembled titanium alloy welded component on the reverse deformation device to ensure that the component does not deform during the welding process;

[0067] Select a suitable anti-deformation device according to the specific weld form of the titanium alloy component, and perform assembly and spot welding. This setting ensures that the component will not undergo uncontrollable deformation due to uneven heat input during the welding process, enhances the stability of the welded structure, reduces the possibility of welding instability, is simple to operate and has low cost, and is suitable for various types of titanium alloy welding scenarios.

[0068] S2: Welding process: Weld the titanium alloy component fixed on the anti-deformation device;

[0069] Perform the welding operation on the titanium alloy component under the support of the anti-deformation device, ensuring the stability and consistency of the component during the welding process and avoiding deformation caused by welding stress. This setting significantly reduces the risk of welding deformation, improves the consistency of welding quality, ensures the fixed position of the component during the welding process, makes the welding more precise, meets the high-precision dimensional requirements, is applicable to titanium alloy materials with different thicknesses and shapes, and has good adaptability.

[0070] S3: Post-weld treatment: Place thermocouples on the weld surface, lay local heating tapes and insulation cotton, and connect the heating tapes, thermocouples to local heating control equipment for heat treatment;

[0071] After welding is completed, place thermocouples on the weld surface, and lay local heating tapes and insulation cotton. Then connect the heating tapes, thermocouples to local heating control equipment for heat treatment, which helps to eliminate the residual stress after welding and further reduce welding deformation. This setting can effectively eliminate welding stress and reduce the residual stress at the welded joint through local heating and heat preservation treatment, thereby reducing deformation. Use thermocouples to monitor the temperature to ensure uniform heating and prevent new deformation caused by local overheating or cooling. It simplifies the process flow, is easy to operate, and improves the quality and dimensional accuracy of the welded parts at the same time.

[0072] S4: Measure the welding deformation to verify the control effect.

[0073] Measure the welding deformation of the titanium alloy component processed through the above steps to verify the effect of the entire control method and ensure the welding quality and dimensional accuracy. This setting can visually evaluate the effect of welding deformation control through precise measurement, and the measurement results can be used to adjust and optimize welding parameters to further improve welding quality.

[0074] Specifically, in step S1, the weld forms are fillet welds and butt welds.

[0075] Fillet welds are mainly used to connect two surfaces that are perpendicular or nearly perpendicular to each other, such as T-joints, corner joints, etc. Using a specially designed anti-deformation tooling, appropriate force can be applied in advance before welding to offset the possible angular deformation during the welding process and ensure that the fillet weld formed after welding meets the design requirements.

[0076] Butt welds are used to butt the end faces of two plates together to form a continuous whole, and are suitable for various occasions such as flat plate splicing and pipeline butt joint. The anti-deformation device can help fix the position of the plates to be welded, preventing bending or warping during the welding process. Especially when dealing with large-sized or thick-walled materials, it can effectively reduce the amount of post-welding correction work and improve production efficiency.

[0077] Specifically, in step S1, the material selected for the anti-deformation device has a certain ability to resist high-temperature deformation, such as heat-resistant steel, nickel-based alloy, titanium alloy, ceramic material, silicon carbide or silicon nitride, etc.

[0078] Heat-resistant steel can maintain sufficient strength and stability in a high-temperature environment, ensuring that the anti-deformation device can effectively support and fix titanium alloy components during the welding process; nickel-based alloys are particularly suitable for applications in extremely high-temperature environments and can maintain high strength and good corrosion resistance at high temperatures; if the anti-deformation device uses the same titanium alloy material as the workpiece to be welded, it can reduce the problem of differences in thermal expansion coefficients caused by material mismatch; ceramic materials can provide support at extremely high temperatures due to their extremely high melting points; silicon carbide and silicon nitride are advanced ceramic materials with extremely high hardness and wear resistance, suitable for use under high-temperature and high-wear conditions.

[0079] This setting can ensure that the anti-deformation device plays the best role in the titanium alloy welding process by selecting suitable materials, reducing welding deformation, and improving welding quality and efficiency.

[0080] Specifically, in step S1, the welding components need to be firmly fixed in the anti-deformation device to ensure that the components do not deform during the welding process. Therefore, it is necessary to strengthen the anti-deformation device according to the size and specifications of the titanium alloy components.

[0081] The strengthened anti-deformation device can fix the titanium alloy components more firmly, thus effectively resisting the deformation caused by uneven heat input during the welding process and reducing the displacement or vibration during the welding process.

[0082] This setting ensures the quality and consistency of the weld, obtains uniform and high-quality welds, avoids cracks or other defects, helps maintain the shape accuracy of the welded parts, reduces the need for post-welding treatment such as correcting deformation, and can significantly reduce the manufacturing cost.

[0083] Specifically, in step S1, the anti-deformation tooling is fixed at 150 mm and 1000 mm from the weld.

[0084] Setting an anti-deformation tooling at a specific distance can more precisely control the deformation that may occur during welding, helping to effectively offset the deformation caused by welding. By fixing the anti-deformation tooling at multiple positions, the welding stress can be dispersed over a larger area, reducing local stress concentration, thereby lowering the deformation risk of the overall structure. For large or complex-shaped titanium alloy components, choosing different fixing points can better adapt to their geometric characteristics, ensuring that all parts can be effectively supported and fixed.

[0085] This setting can ensure that the components do not displace or deform during welding, guaranteeing the quality and consistency of the welds, reducing the need for subsequent rectification. The clear fixing points make the operation more standardized and repeatable, simplifying the process flow, reducing the operation difficulty, improving work efficiency, being able to flexibly handle various different welding tasks, and enhancing the applicability of the process.

[0086] Specifically, in step S3, an anti-oxidation coating is applied to the welded titanium alloy joint position and the adjacent base metal area.

[0087] Titanium alloy is particularly prone to reacting with oxygen in the air at high temperatures, forming a brittle oxide layer. An oxide layer such as TiO2 not only affects the quality of the weld, but may also cause welding defects or reduce the mechanical properties of the welded joint. Applying an anti-oxidation coating can protect the welding area from oxidation during welding, ensuring that the weld metal and the adjacent base metal are not affected by the atmosphere, reducing defects such as porosity and slag inclusion that may occur during welding, thereby improving the overall quality of the weld.

[0088] This setting using an anti-oxidation coating can significantly reduce the incidence of welding defects, improve the success rate and stability of welding, effectively reduce the formation of the oxide layer, and greatly reduce the workload of subsequent removal of the oxide scale or other surface treatments, saving time and cost.

[0089] Specifically, in step S3, thermocouples are placed on the inner and outer surfaces of the weld, and local heating tapes and heat insulation cotton are laid.

[0090] By placing thermocouples on the inner and outer surfaces of the weld, the temperature changes in the welding area can be monitored in real time, ensuring the temperature uniformity and stability during the heating process. By using a combination of local heating tapes and heat insulation cotton, the materials in the welding area and its surroundings can be heated more evenly, reducing the welding stress and deformation caused by too large a temperature gradient. The heat insulation cotton helps to slowly cool the welding area, preventing brittle transformation or crack formation caused by rapid cooling.

[0091] This setting can help operators adjust the heating parameters in a timely manner, ensuring that the welding area is always within the optimal temperature range, effectively reducing the incidence of welding defects, lowering the costs of rework and repair, guaranteeing consistent quality for each welding, reducing the influence of human factors, and improving production efficiency and product consistency.

[0092] Preferably, heat-insulating cotton is laid on the surface of the heating tape, and the heat-insulating cotton completely covers the heating tape.

[0093] The heat-insulating cotton can effectively reduce heat dissipation, enabling the heat generated by the heating tape to act more concentratedly on the welded joint area and the base material nearby, ensuring uniform heating of the weld and the surrounding area. By slowing down the rate of heat diffusion outward, a relatively gentle temperature gradient can be formed in the welding area, avoiding problems such as local overheating or too rapid cooling.

[0094] This setting reduces the occurrence probability of welding defects such as porosity, slag inclusions, and lack of fusion by maintaining temperature uniformity in the welding area, improving the overall quality of the weld. The slow and uniform cooling process helps optimize the microstructure of the welded joint, enhancing its tensile strength, toughness, and corrosion resistance.

[0095] Specifically, in step S3, the center of the weld is located at the center of the local heating tape.

[0096] Placing the center of the weld at the center of the local heating tape can ensure that the welding area, which is the area most in need of temperature control, receives the most concentrated heat input, thus achieving the best heating effect on the weld and the surrounding materials, helping to form a relatively ideal temperature gradient, avoiding problems such as overheating or uneven cooling at the weld, and making the entire welding area heated more uniformly.

[0097] This setting, which places the center of the weld at the center of the local heating tape, can maximize the utilization of heat, avoid unnecessary energy waste, reduce overall energy consumption, and achieve an energy-saving effect.

[0098] Specifically, in step S3, the heating rate, heating temperature, heating width, and holding time should be selected according to the grade and thickness t of the titanium alloy component. The heating width ≥ 3t, the heating rate is 200 - 400 °C / h, the heating temperature is 500 - 800 °C, and the holding time is 1h - 3h.

[0099] Titanium alloys are prone to oxidation at high temperatures, and embrittlement may occur in certain temperature ranges, such as above 800 °C. An appropriate heating rate helps to uniformly heat the titanium alloy components, reducing the thermal stress concentration caused by rapid heating, thereby reducing the residual stress after welding. A holding time of 1 - 3 hours allows the heat to fully penetrate into the titanium alloy interior, enabling the internal stress of the material to be fully released, further reducing the risk of welding deformation and cracks. Ensure that the area covered by the heating band is wide enough, at least three times the thickness of the titanium alloy component, so that the welded area and the base metal around it can be uniformly heated, avoiding problems such as local overheating or uneven cooling, and helping to form a gentle temperature gradient to reduce stress concentration.

[0100] This setting enables the welded area and the surrounding materials to undergo optimal heat treatment, thereby reducing welding deformation and residual stress, and enhancing the quality and stability of the welded joint.

[0101] Specifically, in step S3, the titanium alloy component is cooled to below 100 °C after heating.

[0102] Cooling to below 100 °C can further reduce the chance of reaction between the titanium alloy surface and oxygen in the air, preventing the formation of an oxide layer.

[0103] Specifically, in step S3, after cooling, the anti - deformation device is removed, and the titanium alloy component is sandblasted or polished to remove the anti - oxidation coating.

[0104] After welding and subsequent heat treatment are completed, the anti - deformation device needs to be removed to restore the titanium alloy component to its designed size and shape. Sandblasting or polishing can not only remove the anti - oxidation coating but also further improve the surface finish of the titanium alloy component, removing the oxide layer, spatter, or other surface defects that may occur during the welding process.

[0105] This setting ensures that the dimensional accuracy and shape of the titanium alloy component meet the design requirements, significantly improving the surface quality and corrosion resistance.

[0106] Specifically, in step S4, when the weld form is a fillet weld, the welding of the titanium alloy cylinder 1 and the flange 5 can ensure that the flatness of the surface of the titanium alloy flange 5 is < 1.0 mm. When the weld form is a butt weld, the butt joint of the titanium alloy cylinder 1 can ensure that the ovality of the titanium alloy cylinder 1 is < one - thousandth.

[0107] Example 1

[0108] The butt joint of the cylinder 1 includes the following steps:

[0109] 1. The dimensions of the two cylinders 1 are φ3000 * 40 * 1500 mm;

[0110] 2. Assemble and spot - weld the cylinders 1 in step 1, as shown inFigure 1 as shown;

[0111] 3. Fix the anti-deformation device in step 2 on the assembled titanium alloy cylinder 1, and fix the deformation tooling at 150 mm and 1000 mm from the weld respectively. As shown in Figure 2 The tooling is provided with an adjusting device 4, and the deformation amount can be adjusted as needed;

[0112] 4. Weld the titanium alloy cylinder 1 in step 3;

[0113] 5. Apply anti-oxidation coating to the titanium alloy joint position and the parent material area of the department in step 4, and air dry it;

[0114] 6. Place thermocouples on the inner and outer surfaces of the weld of the cylinder 1 in step 5 to ensure that the thermocouple probe is at the center of the weld;

[0115] 7. Lay a local heating tape on the thermocouple in step 6. The width of the heating tape is 240 mm, and the center of the weld is at the center of the local heating tape;

[0116] 8. Lay heat insulation cotton on the surface of the heating tape in step 7. The heat insulation cotton completely covers the heating tape. As shown in Figure 3 as shown;

[0117] 9). Connect the heating tape, thermocouple in step 8 with the local heating control equipment, heat up to the set temperature and keep it warm for a period of time. The heating rate is 300 °C / h, the heating temperature is 550 °C, and the holding time is 1 h. The heating curve is shown in Figure 3 ;

[0118] 10. Cool the titanium alloy cylinder 1 processed in step 9 to below 100 °C;

[0119] 11. Remove the anti-deformation device from the titanium alloy cylinder 1 processed in step 10;

[0120] 12. Sandblast or polish the weld of the titanium alloy cylinder 1 processed in step 11 to remove the anti-oxidation coating.

[0121] 13. Measure the size of the titanium alloy cylinder 1 processed in step 12. The ovality of the cylinder 1 is less than one-thousandth.

[0122] Example 2

[0123] The fillet weld of the titanium alloy cylinder 1 and the titanium alloy flange 5 includes the following steps:

[0124] 1. The size of the cylinder 1 is φ3000*50*1500 mm, and the size of the flange 5 is φ3150*350*100 mm

[0125] 2. Spot-weld the flange 5 to the cylinder body 1 in step 1, as Figure 1 shown;

[0126] 3. Place the structure assembled by spot welding in step 2 on the platform 203, and fix the anti-deformation device on the flange 5. The anti-deformation device consists of a pressing plate 201 and a spacer 202, and is connected to the platform 203 through connecting bolts 402 to achieve the control of the flange 5. As shown in Figure 2 the tooling, an adjusting device 4 is provided, which can adjust the deformation amount as needed;

[0127] 4. Weld the titanium alloy cylinder body 1 and the flange 5 in step 3;

[0128] 5. Apply anti-oxidation coating to the welded position of the titanium alloy joint and the base metal area in step 4, and let it dry;

[0129] 6. Place a thermocouple on the outer surface of the fillet weld in step 5 to ensure that the thermocouple probe is at the center of the weld;

[0130] 7. Lay a local heating tape on the thermocouple in step 6. The width of the heating tape is 240 mm, and the center of the weld is at the center of the local heating tape;

[0131] 8. Lay heat insulation cotton on the surface of the heating tape in step 7. The heat insulation cotton completely covers the heating tape, as shown in Figure 3 the figure;

[0132] 9). Connect the heating tape and the thermocouple in step 8 to the local heating control equipment, heat up to the set temperature and keep it warm for a period of time. The heating rate is 300 °C / h, the heating temperature is 550 °C, and the holding time is 2 h;

[0133] 10. Cool the titanium alloy weld treated in step 9 to below 100 °C;

[0134] 11. Remove the anti-deformation device from the titanium alloy weld treated in step 10;

[0135] 12. Sandblast or polish the titanium alloy fillet weld treated in step 11 to remove the anti-oxidation coating.

[0136] 13. Measure the size of the titanium alloy flange 5 treated in step 12. The flatness of the flange 5 surface is < 1.0 mm.

[0137] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A device for controlling the welding deformation of titanium alloy, characterized in that The anti-deformation device includes a first anti-deformation device (2) and a second anti-deformation device (3). The first anti-deformation device (2) and the second anti-deformation device (3) are respectively arranged on the inner and outer sides of the cylinder body (1). The first anti-deformation device (2) and the second anti-deformation device (3) are provided with an adjusting device (4), and the adjusting device (4) is used to adjust the deformation amount of the first anti-deformation device (2) and the second anti-deformation device (3) according to the shape of the titanium alloy structural part.

2. The device for controlling the welding deformation of titanium alloy according to claim 1, characterized in that The first anti-deformation device (2) and the second anti-deformation device (3) have the same structure, and the inner diameter of the first anti-deformation device (2) is smaller than the inner diameter of the second anti-deformation device (3).

3. The device for controlling the welding deformation of titanium alloy according to claim 2, wherein When the weld form is a butt weld, the first anti-deformation device (2) is a clamp structure, including a strip-shaped body and the adjusting device (4). The adjusting device (4) is connected to both ends of the strip-shaped body, and the adjusting device (4) adjusts the distance between both ends of the strip-shaped body by tightening and loosening bolts to realize the change of the deformation amount of the first anti-deformation device (2).

4. The device for controlling the welding deformation of titanium alloy according to claim 2, wherein When the weld form is a fillet weld, the first anti-deformation device (2) includes a pressing plate (201), a cushion block (202), a platform (203) and an adjusting device (4). The pressing plate (201) is an annular structure with a notch. The pressing plate (201) has two mutually perpendicular sides for restricting the displacement of the flange (5). The cushion block (202) is arranged between the pressing plate (201) and the platform (203) for adjusting the distance between the pressing plate (201) and the platform (203) to adapt to the fixation of flanges (5) with different thicknesses. The platform (203) is provided with a plurality of parallel strip-shaped grooves (204), and the platform (203) is used to support the welded part and fix the pressing plate (201). The adjusting device (4) includes a connecting bolt (402) and a second connecting groove (403). A plurality of the second connecting grooves (403) are uniformly arranged on the side of the pressing plate (201) away from the flange (5). The second connecting groove (403) is an open groove, and the connecting bolt (402) is used to connect the second connecting groove (403) with the strip-shaped grooves (204) at different positions to change the deformation amount of the pressing plate (201).

5. A method for controlling the welding deformation of titanium alloy, characterized in that, Based on the device for controlling the welding deformation of titanium alloy according to any one of the above claims 1-4, the specific steps are as follows: S1: Preparation before welding: Determine the anti-deformation device according to the weld form of the titanium alloy component, and perform assembly and tack welding. Fix the assembled titanium alloy welded component on the anti-deformation device to ensure that the component does not deform during the welding process. S2: Welding process: Weld the titanium alloy component fixed on the anti-deformation device. S3: Post-weld treatment: Place a thermocouple on the weld surface, lay a local heating tape and heat preservation cotton, and connect the heating tape, thermocouple to the local heating control device for heat treatment. S4: Measure the welding deformation to verify the control effect.

6. The method for controlling the welding deformation of titanium alloy according to claim 5, characterized in that, In step S1, the weld forms are fillet welds and butt welds.

7. The method for controlling the welding deformation of titanium alloy according to claim 5, wherein, In step S1, an anti-deformation tooling is fixed at 150 mm and 1000 mm away from the weld seam.

8. The method for controlling the welding deformation of titanium alloy according to claim 5, characterized in that, In step S3, thermocouples are placed on the inner and outer surfaces of the weld seam, and local heating tapes and heat insulation cotton are laid. The center of the weld seam is at the center of the local heating tape.

9. The method for controlling the welding deformation of titanium alloy according to claim 5, characterized in that, In step S3, the heating rate, heating temperature, heating width, and holding time of the heat treatment are selected according to the grade and thickness t of the titanium alloy component. The heating width ≥ 3t, the heating rate is 200 - 400 °C / h, the heating temperature is 500 - 800 °C, and the holding time is 1 h - 3 h.

10. The method for controlling the welding deformation of titanium alloy according to claim 5, wherein In step S3, after heating, the titanium alloy component is cooled to below 100 °C.

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