A process for controlling welding deformation of thick plate weldments

Abstract

This invention provides a process for controlling welding deformation of thick plate weldments, comprising the following steps: setting up a welding platform and placing a first box and a second box; connecting the first box and the second box; raising the arch at the connection point of the first box and the second box to a first anti-deformation height; assembling an anti-deformation fixture at the top connection point of the first box and the second box; welding the bottom connection point of the first box and the second box; welding one end of a support plate to the top connection point of the first box and the second box; cutting the anti-deformation fixture and adjusting the anti-deformation height to a second anti-deformation height; welding the other end of the support plate and adjusting the anti-deformation height to a third anti-deformation height; simultaneously welding the top weld between the connecting plate and the first box and the second box, monitoring the flatness change during welding and adjusting the flatness to ensure the final flatness meets the standard. The process for controlling welding deformation of thick plate weldments provided by this invention can control welding deformation and weld flatness deviations.

Description

Technical Field

[0001] This invention relates to the field of welding technology, and in particular to a process for controlling welding deformation of thick plate weldments. Background Technology

[0002] The thick plate welded component mainly consists of two box-shaped parts and a top connecting plate, which are welded together to form a closed cavity structure. This requires welding one bottom and two top welds with upward-facing bevels. The steel plates forming the box-shaped parts are 100mm thick, made of Q355B material, and require full penetration testing of the welds, with a post-weld flatness of 5mm. The key to manufacturing is the welding process; conventional direct welding techniques can cause welding deformation, compromising post-weld flatness. Effectively controlling welding deformation and ensuring product dimensions and tolerances meet drawing requirements under conditions of bevel welding and large weld filler are crucial aspects of the manufacturing process. Summary of the Invention

[0003] The purpose of this invention is to solve the problems of large welding deformation and excessive flatness during the welding of thick plates. It proposes a process for controlling the welding deformation of thick plate welded parts, which can control the welding deformation and excessive welding flatness.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A process for controlling welding deformation of a thick plate weldment, the weldment comprising a first box and a second box, wherein the tops of the first and second box are welded together via a connecting plate, and the bottoms of the first and second box are directly welded together, comprising the following steps:

[0006] S1: Set up a welding platform and place the first box and the second box on the welding platform. Adjust the position of the first box and the second box so that the bottom connection of the first box and the second box is located on the welding channel of the welding platform and the first box and the second box are aligned.

[0007] S2: Weld multiple fixing plates along the length of the bottom of the connection between the first box and the second box to connect the first box and the second box;

[0008] S3: Arch the connection between the first box and the second box to make the anti-deformation height reach the first anti-deformation height;

[0009] S4: Assemble the anti-deformation tooling between the top of the first box and the top of the second box;

[0010] S5: Welding at the bottom connection forms a bottom weld;

[0011] S6: A support plate is installed between the first box and the second box under the anti-deformation fixture. One end of the support plate is welded and fixed to the first box or the second box, and the other end of the support plate is not welded for the time being.

[0012] S7: While cutting the anti-deformation fixture, monitor the change in flatness and stop cutting the anti-deformation fixture when the anti-deformation height changes from the first anti-deformation height to the second anti-deformation height.

[0013] S8: Weld the other end of the support plate to the second box or the first box, cut off the anti-deformation fixture, monitor the flatness, and change the anti-deformation height from the second anti-deformation height to the third anti-deformation height;

[0014] S9: Simultaneously weld the top weld between the connecting plate and the first and second housings. Monitor the flatness changes during welding and adjust the flatness to the final flatness to meet the standard.

[0015] Furthermore, in step S1, the welding platform includes a first platform and a second platform. The first platform is used to place the first box, and the second platform is used to place the second box. The first platform and the second platform are placed parallel to each other but do not contact each other. A welding channel is formed between the first platform and the second platform to facilitate operation from the bottom of the first box and the second box within the welding channel.

[0016] Furthermore, in step S1, an alignment fixture is used to achieve fine-tuning alignment of the first box and the second box. The alignment fixture includes a positioning block and a guide block, which are connected by bolts. The positioning block and the guide block are welded to the first box and the second box respectively. Tightening the bolts facilitates the alignment of the first box and the second box.

[0017] Furthermore, in step S3, the connection between the first box and the second box is arched higher. Specifically, the first box and the second box near the connection are arched simultaneously using jacks, so that the connection between the first box and the second box is higher than the first anti-deformation height of the horizontal plane where the welding platform is located.

[0018] Furthermore, the anti-deformation fixture is a U-shaped fixture, with its two ends welded to the first and second housings respectively.

[0019] Furthermore, in step S7, an oxy-acetylene torch is used to cut the anti-deformation fixture.

[0020] Furthermore, in step S8, after cutting off the anti-deformation fixture, the flatness is measured. When the anti-deformation height is not the third anti-deformation height, the bottom weld is flame straightened to make the anti-deformation height the third anti-deformation height.

[0021] Furthermore, in step S9, the flatness can be adjusted to the final flatness by either continuing to raise the arch or lowering the connection between the first and second boxes.

[0022] Furthermore, in step S9, the flatness can be adjusted to the final flatness by increasing or decreasing the welding current.

[0023] Furthermore, the first anti-deformation height is 15mm; the second anti-deformation height is 7mm; the third anti-deformation height is 4.5mm, and the final flatness is 5mm.

[0024] Compared with the prior art, the process for controlling welding deformation of thick plate welded parts provided by the present invention has the following beneficial effects:

[0025] 1. During the welding process, both the first and second housings are relatively heavy and large in volume. Ensuring that the first and second housings are perfectly aligned front-to-back and side-to-side without any gaps is a challenge in the welding process. In this invention, an alignment fixture is used to achieve fine-tuning alignment of the first and second housings. The alignment fixture includes a positioning block and a guide block, which are connected by bolts. The positioning block and guide block are welded to the first and second housings respectively, and tightening the bolts facilitates alignment of the first and second housings.

[0026] 2. When welding the bottom weld, the top cannot be fitted with a connecting plate, leaving it in an open state, resulting in significant welding deformation that is difficult to correct. In this invention, before welding the bottom weld, multiple fixing plates are welded along the length of the connection between the first and second housings to connect them. Then, the connection between the first and second housings is arched to achieve the first anti-deformation height. An anti-deformation fixture is then fitted between the tops of the first and second housings, effectively controlling welding deformation. During the bottom weld, because the anti-deformation fixture is installed, the flatness remains almost unchanged; therefore, only the flatness of the final bottom weld needs to be measured.

[0027] 3. When welding the top weld, a closed cavity is formed between the first box, the second box, and the connecting plate. Since the cavity lacks internal rigidity, the welding shrinkage between the connecting plate and the first and second boxes is significant, easily leading to flatness deviations. In this invention, before assembling the connecting plate, a support plate is installed between the first and second boxes under an anti-deformation fixture to enhance structural rigidity and control welding deformation during the welding of the top weld.

[0028] 4. In this invention, during the welding process, a phased reverse deformation method is adopted. First, after connecting the first box and the second box, the connection point between the first box and the second box is arched to make the reverse deformation height reach the first reverse deformation height. Second, after welding the bottom weld and before welding the support plate, the anti-deformation fixture is cut to change the reverse deformation height from the first reverse deformation height to the second reverse deformation height. Third, the other end of the support plate is welded to the second box or the first box, the anti-deformation fixture is cut off, and the flatness is monitored to change the reverse deformation height from the second reverse deformation height to the third reverse deformation height. In this state, the welding of the top connecting plate begins.

[0029] 6. When welding the top weld, the flatness is constantly changing. It is necessary to monitor and measure the bottom flatness in real time. The flatness can be adjusted to the final flatness by continuing to arch the top or lowering the connection between the first and second boxes; or by increasing or decreasing the welding current. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the first box, the second box, and the connecting plate before welding in this invention;

[0031] Figure 2 This is a schematic diagram of the structure of the first box, the second box, and the connecting plate after welding in this invention;

[0032] Figure 3 A flowchart of the process for controlling welding deformation of thick plate welded parts provided by the present invention;

[0033] Figure 4 A structural schematic diagram showing the arch height at the connection point between the first and second boxes;

[0034] Figure 5 A schematic diagram showing the connection between the anti-deformation tooling and the first and second housings;

[0035] Figure 6 This is a schematic diagram showing the connection between the support plate and the first and second housings.

[0036] In the diagram, 1. First box; 2. Second box; 3. Anti-deformation fixture; 4. Support plate; 5. Connecting plate; 6. Fixing plate. Detailed Implementation

[0037] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0038] like Figure 1-2 As shown, Figure 1 This is a schematic diagram of the structure of the first box 1, the second box 2, and the connecting plate 5 before welding in this invention. Figure 2This is a schematic diagram of the structure of the first box 1, the second box 2 and the connecting plate 5 after welding in this invention; the welded parts include the first box 1 and the second box 2, the top of the first box 1 and the second box 2 are welded together by the connecting plate 5, and the bottom of the first box 1 and the second box 2 are directly welded together.

[0039] The first housing 1, the second housing 2, and the top connecting plate 5 are welded together to form a closed cavity structure. This requires welding one bottom and two top welds with upward-facing bevels. The steel plates composing the housings are 100mm thick, made of Q355B material. Full penetration testing of the welds is required, and the post-weld flatness must reach 5mm. Conventional direct welding techniques can cause welding deformation, resulting in unreliable post-weld flatness. To address the problems of large welding deformation and difficulty in achieving the required flatness, this invention provides a process for controlling welding deformation in thick plate weldments. The process flow diagram is shown below. Figure 3 As shown.

[0040] The process for controlling welding deformation of thick plate welded parts provided by the present invention includes the following steps:

[0041] S1: Set up a welding platform and place the first box 1 and the second box 2 on the welding platform. Adjust the position of the first box 1 and the second box 2 so that the bottom connection of the first box 1 and the second box 2 is located on the welding channel of the welding platform and the first box 1 and the second box 2 are aligned.

[0042] In some preferred embodiments, the welding platform includes a first platform and a second platform. The first platform is used to place a first housing 1, and the second platform is used to place a second housing 2. The first platform and the second platform are placed parallel to each other but not in contact, forming a welding channel between the first platform and the second platform, facilitating operation from the bottom of the first housing 1 and the second housing 2 within the welding channel. In actual welding, readily available materials can be used, such as a rigid, flat square box, as the first platform and the second platform.

[0043] Both the first housing 1 and the second housing 2 are relatively heavy and large in volume. Ensuring that the first housing 1 and the second housing 2 are perfectly aligned front-to-back and side-to-side is a challenge during welding. In step S1, an alignment fixture is used to fine-tune the alignment of the first housing 1 and the second housing 2. The alignment fixture includes a positioning block and a guide block, which are connected by bolts. The positioning block and the guide block are welded to the first housing 1 and the second housing 2 respectively. Tightening the bolts facilitates the alignment of the first housing 1 and the second housing 2.

[0044] S2: Weld multiple fixing plates 6 along the length of the bottom of the connection between the first box 1 and the second box 2 to connect the first box 1 and the second box 2. Specifically, welding personnel need to enter the welding channel and weld at the bottom of the connection between the first box 1 and the second box 2. Generally, three fixing plates 6 are welded along the length, located at the beginning, end and middle of the bottom connection, respectively. This can play a good fixing role and prevent the first box 1 and the second box 2 from separating during the subsequent reverse deformation process. After welding the fixing plates 6, the alignment fixture can be removed.

[0045] S3: Raise the arch at the connection point between the first box 1 and the second box 2 so that the anti-deformation height reaches the first anti-deformation height. Figure 4 This is a structural diagram showing the arch height at the connection point of the first and second housings. Specifically, by using jacks, the arch height of the first housing 1 and the second housing 2 near the connection point is increased, so that the connection point of the first housing 1 and the second housing 2 is higher than the first anti-deformation height of the horizontal plane where the welding platform is located.

[0046] S4: Assemble the anti-deformation fixture 3 between the top of the first housing 1 and the top of the second housing 2. Figure 5 This is a structural diagram showing the connection between the anti-deformation fixture and the first and second housings. The anti-deformation fixture 3 is a U-shaped fixture. The two ends of the anti-deformation fixture 3 are welded to the first housing 1 and the second housing 2, respectively. The U-shape is achieved by hollowing out the middle of the square block, which can reduce the weight of the anti-deformation fixture 3, and the hollow in the middle also makes it easier to handle and hold.

[0047] S5: The bottom weld is formed at the bottom connection. During the welding of the bottom weld, the flatness remains almost unchanged due to the installation of the anti-deformation fixture 3. Therefore, the flatness only needs to be measured after the final bottom weld is welded. After the bottom weld is completed, a flaw detection test must be performed.

[0048] In this invention, when welding the bottom weld, the connecting plate 5 cannot be assembled at the top, leaving the top open and resulting in significant welding deformation that is difficult to correct. Before welding the bottom weld, multiple fixing plates 6 are welded along the length of the bottom of the connection between the first housing 1 and the second housing 2 to connect them. Then, the connection between the first housing 1 and the second housing 2 is arched to achieve the first anti-deformation height. Finally, an anti-deformation fixture 3 is assembled between the top of the first housing 1 and the top of the second housing 2, effectively controlling welding deformation.

[0049] S6: A support plate 4 is installed between the first housing 1 and the second housing 2, under the anti-deformation fixture 3. One end of the support plate 4 is welded to either the first housing 1 or the second housing 2, while the other end is not welded at this time. When welding the top weld, since a closed cavity is formed between the first housing 1, the second housing 2, and the connecting plate 5, the interior lacks rigidity. The welding shrinkage between the connecting plate 5 and the first housing 1 and the second housing 2 is large, easily leading to excessive flatness. In this invention, before assembling the connecting plate 5, a support plate 4 is installed between the first housing 1 and the second housing 2, under the anti-deformation fixture 3, to enhance structural rigidity and control welding deformation during the welding of the top weld.

[0050] S7: While cutting the anti-deformation fixture 3 with an oxy-acetylene torch, monitor the change in flatness and stop cutting the anti-deformation fixture 3 when the anti-deformation height changes from the first anti-deformation height to the second anti-deformation height.

[0051] S8: Weld the other end of the support plate 4 to the second housing 2 or the first housing 1. Figure 6 This is a structural diagram showing the connection between the support plate and the first and second housings. The anti-deformation fixture 3 is cut off, and the flatness is monitored to change the anti-deformation height from the second anti-deformation height to the third anti-deformation height.

[0052] In this invention, the reverse deformation method is adopted in stages during the welding process. First, after connecting the first box 1 and the second box 2, the connection point of the first box 1 and the second box 2 is arched to make the reverse deformation height reach the first reverse deformation height. Second, after welding the bottom weld and before welding the support plate 4, the reverse deformation height is changed from the first reverse deformation height to the second reverse deformation height by cutting the anti-deformation fixture 3. Third, the other end of the support plate 4 is welded to the second box 2 or the first box 1, the anti-deformation fixture 3 is cut off, and the flatness is monitored to make the reverse deformation height change from the second reverse deformation height to the third reverse deformation height. In this state, the welding of the top connecting plate 5 begins.

[0053] S9: Simultaneously weld the top weld between the connecting plate 5 and the first box 1 and the second box 2. Monitor the flatness change during welding and adjust the flatness to ensure that the final flatness meets the standard.

[0054] The first anti-deformation height is 15mm; the second anti-deformation height is 7mm; the third anti-deformation height is 4.5mm, and the final flatness is 5mm.

[0055] When welding the top weld, the flatness is constantly changing, so it is necessary to monitor and measure the bottom flatness in real time. The flatness can be adjusted to the final flatness by continuing to arch the top or lowering the connection between the first box 1 and the second box 2; or by increasing or decreasing the welding current.

[0056] The above description is only of the preferred embodiment of the present invention and should not be construed as limiting the scope of the claims. The present invention is not limited to the above embodiments, and variations in its specific structure are permitted. All variations made within the scope of the independent claims of the present invention are also within the scope of protection of the present invention.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Claims

1. A process for controlling welding deformation of a thick plate weldment, the weldment comprising a first box and a second box, wherein the tops of the first and second box are welded together via a connecting plate, and the bottoms of the first and second box are directly welded together, characterized in that... Includes the following steps: S1: Set up a welding platform and place the first box and the second box on the welding platform. Adjust the position of the first box and the second box so that the bottom connection of the first box and the second box is located on the welding channel of the welding platform and the first box and the second box are aligned. S2: Weld multiple fixing plates along the length of the bottom of the connection between the first box and the second box to connect the first box and the second box; S3: Arch the connection between the first box and the second box to make the anti-deformation height reach the first anti-deformation height; S4: Assemble the anti-deformation fixture between the top of the first box and the top of the second box; S5: Welding at the bottom connection forms a bottom weld; S6: A support plate is provided between the first box and the second box under the anti-deformation tooling. One end of the support plate is welded and fixed to the first box or the second box, and the other end of the support plate is not welded. S7: While cutting the anti-deformation fixture, monitor the change in flatness and stop cutting the anti-deformation fixture when the anti-deformation height changes from the first anti-deformation height to the second anti-deformation height. S8: Weld the other end of the support plate to the second box or the first box, cut off the anti-deformation fixture, monitor the flatness, and change the anti-deformation height from the second anti-deformation height to the third anti-deformation height; S9: Simultaneously weld the top weld between the connecting plate and the first box and the second box. Monitor the flatness change during welding and adjust the flatness to ensure that the final flatness meets the standard.

2. The process for controlling welding deformation of thick plate weldments according to claim 1, characterized in that, In step S1, the welding platform includes a first platform and a second platform. The first platform is used to place the first box and the second platform is used to place the second box. The first platform and the second platform are placed parallel to each other but do not contact each other. A welding channel is formed between the first platform and the second platform to facilitate operation from the bottom of the first box and the second box within the welding channel.

3. The process for controlling welding deformation of thick plate weldments according to claim 1, characterized in that, In step S1, an alignment fixture is used to achieve fine-tuning alignment of the first box and the second box. The alignment fixture includes a positioning block and a guide block. The positioning block and the guide block are connected by bolts. The positioning block and the guide block are respectively welded to the first box and the second box to facilitate alignment of the first box and the second box.

4. The process for controlling welding deformation of thick plate weldments according to claim 1, characterized in that, In step S3, the connection point between the first box and the second box is raised. Specifically, the first box and the second box near the connection point are raised simultaneously using jacks, so that the connection point is higher than the horizontal plane of the welding platform.

5. The process for controlling welding deformation of thick plate weldments according to claim 1, characterized in that, The anti-deformation fixture is a U-shaped fixture, and its two ends are welded to the first box and the second box, respectively.

6. The process for controlling welding deformation of thick plate weldments according to claim 1, characterized in that, In step S7, an oxy-acetylene torch is used to cut the anti-deformation fixture.

7. The process for controlling welding deformation of thick plate weldments according to claim 1, characterized in that, In step S8, after cutting off the anti-deformation fixture, the flatness is measured. When the anti-deformation height is not the third anti-deformation height, the bottom weld is flame straightened to make the anti-deformation height the third anti-deformation height.

8. The process for controlling welding deformation of thick plate weldments according to claim 1, characterized in that, In step S9, the flatness can be adjusted to the final flatness by either continuing to raise the arch or lowering the connection between the first and second boxes.

9. The process for controlling welding deformation of thick plate weldments according to claim 1, characterized in that, In step S9, the flatness can be adjusted to the final flatness by increasing or decreasing the welding current.

10. The process for controlling welding deformation of thick plate welded parts according to claim 1, characterized in that, The first anti-deformation height is 15mm; the second anti-deformation height is 7mm; the third anti-deformation height is 4.5mm, and the final flatness is 5mm.

Images