Method for controlling welding deformation of thin plate
Through the combination of plasma cutting, cold processing equipment and laser welding machine, the deformation of thin plate welding is controlled, and the deformation problem in marine thin plate welding is solved, and the deformation control of the entire process from pre-processing to welding is realized, which improves the welding quality and the stability and aesthetics of the ship structure.
Patent Information
- Application Number
- CN202510721269.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-30
- Publication Date
- 2025-07-25
AI Technical Summary
There are problems of large deformation, difficult to control the size and hardening during the welding process of existing marine thin plates, which affects the safety and aesthetics of the ship structure and is difficult to prevent welding deformation.
Plasma cutting and cutting are used, and the bevel is prepared using cold processing equipment. The amount of edges and gaps in the assembly stage are controlled, the welding sequence is changed, the welding is positioned using a laser welding machine, and post-weld deformation correction is carried out through thermal correction.
Effectively control the deformation of thin plate welding, reduce deformation from pre-processing to welding, improve welding quality and accuracy, and ensure the stability and aesthetics of the ship structure.
Smart Images
Figure CN120362773A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of thin plate welding, and particularly to a method for controlling thin plate welding deformation. Background Art
[0002] When welding existing marine thin plates, a carbon dioxide shielded welding machine is used for welding. During the welding process, problems such as large deformation, difficult size control, and welding hardening are extremely likely to occur. These problems seriously affect the normal installation of subsequent outfitting and supporting facilities of the ship, and pose a serious impact on the safety of the ship structure. At the same time, the welding deformation of thin plates will also affect the hull structure, not only affecting the aesthetics of the hull, but also causing the subsequent modular installation to be unable to proceed smoothly. At present, only the deformation treatment after thin plate welding can be carried out, and the welding deformation of thin plates cannot be well prevented. The present invention proposes a method that can comprehensively prevent welding deformation before, during, and after thin plate welding. Summary of the Invention
[0003] The purpose of the present invention is to provide a method for controlling thin plate welding deformation, which solves the problem that welding deformation cannot be comprehensively controlled.
[0004] In order to achieve the above purpose, the technical solution adopted by the present invention is:
[0005] A method for controlling thin plate welding deformation includes:
[0006] S1. Deformation control in the preprocessing stage: Use plasma cutting to cut the material, and select cold working equipment to prepare the groove;
[0007] S2. Deformation control in the assembly stage: Control the misalignment amount, root gap of fillet welds, and root gap of the groove during the assembly of thin plates to ensure the flatness of thin plates during the welding process;
[0008] S3. Deformation control in the welding stage: First, perform positioning welding on the thin plate, and then perform formal welding; Positioning welding is to position the thin plate through welding; In the positioning welding stage, first weld the longitudinal long welds that have a greater impact on the deformation of the thin plate, and then weld the transverse short welds; In the formal welding stage, first weld the transverse segment welds, and then weld the longitudinal long welds;
[0009] S4. Deformation control in the post-welding stage: Perform deformation correction on the welding position.
[0010] Furthermore, laser cutting is used for plasma cutting to cut the thin plate, and a planer or milling machine is selected as the cold working equipment.
[0011] Furthermore, the misalignment amount during the assembly of thin plates is controlled within 0 - 0.1 times the thickness of the thin plate, the root gap of fillet welds is controlled within 0 - 0.5 mm, and the root gap of the groove is controlled within 0 - 1 mm.
[0012] Furthermore, when welding on openings or curved surfaces, the method of inserting plate welding is adopted. Before welding, heavy objects are used to ballast the thin plate to ensure the flatness of the thin plate. After welding, the heavy objects are removed to eliminate the ballast.
[0013] Furthermore, the method of tack welding needs to be carried out by a laser welding machine, and it is ensured that the diameter of the welding wire used is 1.0 mm, the current is controlled at 180 - 220 A, the voltage is 24 - 28 V, and the speed is 8 - 12 mm / s.
[0014] Furthermore, the welding position is corrected for deformation by thermal straightening; the thermal straightening is to perform long-strip heating on the back of the thin plates on both sides of the deformed weld, and then perform short-strip heating on both sides of the weld. After heating, it is cooled with water.
[0015] Furthermore, during the process of heating the thin plates on both sides of the weld, it is necessary to ensure that the distance between the weld and the heating line is more than 30 mm.
[0016] Furthermore, when the deformation is relatively serious, an external force can be applied to the thin plate, that is, heavy objects are added to the thin plate to ballast it, so as to achieve the purpose of correcting the deformation of the thin plate.
[0017] Furthermore, when welding long welds, the method of segmental backstep welding is adopted.
[0018] By adopting the above technical solutions, the beneficial technical effects of the present invention are:
[0019] Before welding, the present invention cuts the material by an ion cutting machine, reduces the stress applied to the thin plate during processing, and reduces the stress deformation of the thin plate. A cold working device is used to bevel the thin plate, reducing the heat input to the thin plate and reducing welding deformation. During assembly, the position of the thin plate is accurately controlled to prevent stress from being generated inside the thin plate and causing deformation. During welding, by changing the welding sequence, long welds in the welding process are reduced, and welding deformation is also reduced. After welding is completed, the weld is processed by thermal straightening. The present invention can effectively control welding deformation from the pre-processing stage of the thin plate to after welding, so as to improve the welding quality of the thin plate. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 It is a sequence diagram of the weld during the tack welding stage.
[0021] Figure 2 It is a sequence diagram of the weld during the formal welding stage. DETAILED DESCRIPTION OF THE INVENTION
[0022] A method for controlling the welding deformation of a thin plate includes:
[0023] S1. Control the deformation of the thin plate in the pre-processing stage: First, when cutting the material, use plasma cutting technology such as laser cutting to cut the material, preventing stress from being generated on the thin plate. Traditional cutting devices will be placed on the thin plate and generate stress on the thin plate, resulting in stress deformation of the thin plate; then select cold processing equipment such as a planer or a milling machine to prepare the groove on the thin plate, which will reduce the heat input to the thin plate and reduce the deformation rate of the thin plate;
[0024] S2. Control the deformation of the thin plate in the assembly stage: First, control the gaps of the thin plate, control the misalignment during the assembly of the thin plate within 0 to 0.1 times the thickness of the thin plate, control the root gap of the fillet weld within 0 to 0.5 mm, and control the root gap of the groove within 0 to 1 mm; and ensure the flatness of the thin plate during the welding process;
[0025] S3. Control the deformation of the thin plate in the welding stage: First, perform tack welding on the thin plate, and then perform formal welding; Tack welding is to position the thin plate through welding. When performing tack welding, a laser welding machine will be used for welding. The laser welding machine can achieve a relatively small heat input, effectively reducing the welding deformation of the thin plate; as Figure 1 shown, the welding sequence of the weld in the tack welding stage is to first weld the longitudinal long weld that has a greater impact on the deformation of the thin plate, and then weld the transverse short weld; weld the gaps at No. 1 in sequence, and finally weld the transverse short seams at 2-6; as Figure 2 shown, the welding sequence of the weld in the formal welding stage is to first weld the transverse section weld, and then weld the longitudinal long weld. First, weld the numbers 1-5 in sequence, and then weld the numbers 6 and 7 in sequence; this will avoid long-term heat input to the thin plate and reduce the deformation rate of the thin plate;
[0026] S4. Control the deformation of the thin plate in the post-welding stage: Correct the deformation of the welding position by means of thermal straightening for the welding position.
[0027] When the plate is open-hole or curved surface welding, and the plates form a curved surface line, because the heat input for welding the small plates is small, the method of inserting plate welding is usually selected, which is not easy to cause deformation of the curved surface. However, before welding, weights should be added around the welding position to apply pressure to the thin plate to prevent the thin plate from deforming during the welding process, and then remove the weights after welding is completed, effectively reducing the welding deformation. When the weld length is long, the method of segmented backstep welding is usually used for welding, decomposing the long weld into multiple small welds, reducing the heat input to the thin plate and reducing the deformation rate of the thin plate.
[0028] The method of positioning welding needs to use a laser welding machine for welding, and ensure that the wire diameter used is 1.0 mm, the current is controlled at 180 - 220 A, the voltage is 24 - 28 V, and the speed is 8 - 12 mm / s. When ensuring that the moving speed of laser welding is 8 - 12 mm / s, the lateral shrinkage of the thin plate is significantly reduced.
[0029] When the deformation situation is not very serious, the method of thermal straightening is usually used to control welding deformation. The thermal straightening is to perform long-strip heating on the back of the thin plates on both sides of the deformed weld, and then perform short-strip heating on both sides of the weld. When the deformation degree is small, the deformation can be restored after the heating process. When the deformation does not recover after the heating process, it is cooled with water after the heating stage, and the restoration of the deformation is achieved by applying the principle of thermal expansion and contraction. During the process of heating the thin plates on both sides of the weld, it is necessary to ensure that the distance between the weld and the heating line is more than 30 mm.
[0030] When the deformation situation is relatively serious, a heavy object with an area larger than the thin plate can be added to the thin plate, that is, pressure is applied to the thin plate. After placing it for a period of time, the deformation amount of the thin plate will be effectively reduced, so as to achieve the purpose of correcting the deformation of the thin plate.
[0031] Certainly, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by those skilled in the art within the scope of the essence of the present invention should also fall within the protection scope of the present invention.
Claims
1. A method for controlling the welding deformation of thin plates, characterized in that, Including: S1. Deformation control in the pre - processing stage: Use plasma cutting for blanking and select cold - working equipment to prepare the groove. S2. Deformation control in the assembly stage: Control the misalignment amount, root gap of fillet welds, and root gap of the groove during the assembly of thin plates to ensure the flatness of the thin plates during the welding process. S3. Deformation control in the welding stage: First, perform tack welding on the thin plates, and then carry out formal welding; Tack welding is to position - weld the thin plates; In the tack - welding stage, first weld the longitudinal long welds that have a greater impact on the deformation of the thin plates, and then weld the transverse short welds; In the formal - welding stage, first weld the transverse - section welds, and then weld the longitudinal long welds. S4. Deformation control in the post - welding stage: Carry out deformation correction on the welding positions.
2. A method for controlling the welding deformation of thin plates according to claim 1, characterized in that, For the plasma cutting mentioned above, laser cutting is used for blanking the thin plates, and the cold - working equipment selected is a planer or a milling machine.
3. A method for controlling the welding deformation of thin plates according to claim 1, characterized in that, Control the misalignment amount during the assembly of thin plates within 0 - 0.1 times the thickness of the thin plates, control the root gap of fillet welds within 0 - 0.5 mm, and control the root gap of the groove within 0 - 1 mm.
4. A method for controlling the welding deformation of a thin plate according to claim 1, characterized in that, When welding openings or curved surfaces, the method of inserting - plate welding is adopted. Before welding, use heavy objects to press - load the thin plates to ensure the flatness of the thin plates. After welding, remove the heavy objects and the press - load.
5. A method for controlling the welding deformation of thin plates according to claim 1, characterized in that, The method of tack welding needs to be carried out using a laser welder, and ensure that the diameter of the welding wire used is 1.0 mm, the current is controlled within 180 - 220 A, the voltage is 24 - 28 V, and the speed is 8 - 12 mm / s.
6. A method for controlling the welding deformation of thin plates according to claim 1, characterized in that, Carry out deformation correction on the welding positions through thermal straightening; The thermal straightening is to perform long - strip heating on the back of the thin plates on both sides of the deformed weld, and then perform short - strip heating on both sides of the weld. After heating, cool with water.
7. A method for controlling the welding deformation of thin plates according to claim 6, characterized in that, During the process of heating the thin plates on both sides of the weld, ensure that the distance between the weld and the heating line is more than 30 mm.
8. A method for controlling the welding deformation of thin plates according to claim 1, characterized in that, When the deformation situation is relatively serious, an external force can be applied to the thin plates, that is, add heavy objects on the thin plates to press - load the thin plates to achieve the purpose of correcting the deformation of the thin plates.
9. A method for controlling the welding deformation of thin plates according to claim 1, characterized in that, When welding long welds, adopt the method of segmental back - step welding for welding.