Method for adjusting the welding deformation of a horizontal plate

Abstract

The application discloses a horizontal plate welding deformation flame adjusting method, after the horizontal plate and the vertical pipe are assembled and welded, the size tolerance of the horizontal plate is detected first; if the actual size exceeds the standard range, the to-be-heated area and the to-be-heated path are demarcated on the horizontal plate surface, the to-be-heated area is corrected by adopting the point heating and surface heating combined mode, the size is re-detected after cooling and compared with the standard; then, the line heating correction is implemented along the symmetrically arranged to-be-heated path, and the roundness of the horizontal plate is detected after cooling. The method has the advantages that the stress of the heating area is uniform, the cooling contraction is synchronous, the horizontal plate is not easy to be laterally twisted and deviated during the correction, the correction precision is excellent, the residual stress of the horizontal plate can be uniformly released, the stress local concentration can be avoided, the cracking probability is reduced, the single correction forming effect is good, the repeated heating and trimming are reduced, the local overheating damage to the horizontal plate is avoided, and the flatness and the overall size precision of the horizontal plate are effectively ensured.

Description

Technical Field

[0001] This invention belongs to the field of marine oil engineering construction technology, and particularly relates to a method for adjusting the flame deformation during horizontal plate welding. Background Technology

[0002] Currently, the construction of offshore oil platforms involves a large amount of welding work; among them, the assembly welding of the large-sized riser (cylindrical) and the horizontal plate, which are the main structural components of offshore oil platforms, is extremely common. This process requires welding the end of the riser to the end face of the horizontal plate perpendicularly.

[0003] However, due to the deformation of the horizontal plate during welding (warping outwards around the edges and protruding in the center), the dimensions of the structural components exceed the tolerance requirements of the project specifications, so mechanical methods are required for correction. However, mechanical straightening not only has a large springback, but also requires repeated overpressure correction. If the internal stress of the horizontal plate is not released, it is very easy to deform again after temperature changes or transportation. In addition, mechanical straightening is also prone to producing indentations, roller marks, hammer pits, scratches, etc.

[0004] Therefore, it is urgent to design a method for adjusting the welding deformation flame of horizontal plates to solve the problems mentioned above. Summary of the Invention

[0005] The purpose of this invention is to provide a method for adjusting the flame deformation of horizontal plate welding, which has the advantages of easy correction and deviation, reduced residual internal stress and better plate levelness, thus solving the problems involved in the background art.

[0006] To achieve the above objectives, the specific technical solution of the horizontal plate welding deformation flame adjustment method of the present invention is as follows: A method for adjusting the flame deformation during welding of a horizontal plate mainly includes the following steps: S1. After the horizontal plate and the riser assembly are welded together, measure the dimensional tolerances of the horizontal plate. S2. If the final dimensions of the water platform are not within the specified range, mark the area to be heated and the path to be heated along the surface of the horizontal plane. S3. Correct the area to be heated by using point heating and surface heating methods; S4. After the area to be heated has cooled naturally, measure it again and compare it with the specified dimensions; S5. Correction is performed along the symmetrical path to be heated by line heating. Among them, a reference circle and its center are drawn on the surface of the horizontal plate away from the riser, corresponding to the weld at the riser port. The symmetrical point on the circumference of the reference circle is taken as the starting point of the line heating, and the line heating is carried out uniformly on the surface of the horizontal plate along the radius of the reference circle towards the center. S6. After the heated path has cooled naturally, remeasure the levelness of the reference circle.

[0007] Furthermore, in S1, the end of the riser is vertically welded to one side of the horizontal plate. After the horizontal plate cools naturally, the assembled riser and horizontal plate are rotated as a whole.

[0008] Furthermore, in S2, a first heating path is drawn along the welding position on the side of the horizontal plate away from the riser, and a heating area is drawn along the circumference of the horizontal plate and between the first heating path.

[0009] Furthermore, in S3, the wave deformation within the heating area is point-heated, and the torsional deformation of the heating area is adjusted by surface heating.

[0010] Furthermore, in S5, an initial heating point is selected on the first path to be heated, and the first path to be heated is heated at a constant speed starting from the initial heating point, so as to straighten the entire area to be heated.

[0011] Furthermore, in S5, two sets of symmetrical points are selected along the circumference of the reference circle as the starting points for line heating. The four starting points are spaced 90 degrees apart on the circumference to form four second paths to be heated. The four second paths to be heated are respectively directed radially toward the center of the reference circle and are uniformly heated on the surface of the horizontal plate.

[0012] Furthermore, during the heating process along the radius of the reference circle toward the center line, the heating width of the second path to be heated gradually increases.

[0013] Furthermore, the heating temperatures for point heating, surface heating, and line heating must be measured on the surface of the horizontal plate being heated, and the measurement interval must not exceed 2 minutes to ensure that the temperature of the heating area does not exceed 500 degrees Celsius.

[0014] Furthermore, the flame peak of the inner flame should be kept 8-10 mm away from the surface of the horizontal plate and at least 15 mm away from the weld.

[0015] Furthermore, in S6, limit blocks are set at both ends of the horizontal plate on the side away from the riser, and a standard line is connected between the limit blocks. The levelness is judged by measuring the distance between each position of the reference circle and the standard line.

[0016] The horizontal plate welding deformation flame adjustment method of the present invention has the following advantages: (1) The present invention causes the horizontal plate to be subjected to force from the outside to the inside: the ring is heated and cooled simultaneously, and the contraction force is gathered from the outer ring to the center, which is suitable for correcting the edge warping and outer ring deformation of the plate.

[0017] (2) The present invention has strong controllability of deformation: the shrinkage of the ring heating is uniform and stable, and it is not easy to overcorrect. The plane dimensions of the horizontal plate are easier to control within the tolerance range.

[0018] (3) The present invention has balanced stress and is not easy to deviate during correction: the two sides are heated symmetrically and shrink synchronously, the correction tension is balanced with each other, the horizontal plate will not bend or twist, and the shape is more regular after correction.

[0019] (4) The present invention can uniformly release the residual stress inside the horizontal plate, and the stress is not easy to accumulate locally, reducing the risk of cracking of the plate. The single correction and forming effect is good, reducing the number of repeated heating and repairs, while avoiding local overheating damage to the horizontal plate, and better ensuring the flatness and overall dimensional accuracy of the horizontal plate. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the assembly and welding of the horizontal plate and the vertical pipe of the present invention; Figure 2 This is a schematic diagram of the operation of Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the operation of Embodiment 2 of the present invention; Figure 4 This is a schematic diagram of the operation of Embodiment 3 of the present invention.

[0021] Explanation of markings in the diagram: 1. Horizontal plate; 2. Vertical pipe; 3. Area to be heated; 4. First path to be heated; 5. Second path to be heated; 6. Reference circle; 7. Center of the circle; 8. Limiting block; 9. Standard line. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0024] The following is a reference to the appendix. Figure 1 To be continued Figure 4 The present invention describes a method for adjusting the flame deformation during horizontal plate welding.

[0025] like Figure 1 and Figure 2 As shown, the horizontal plate welding deformation flame adjustment method of the present invention mainly includes the following steps: S1. After the horizontal plate 1 and the vertical pipe 2 are welded together, measure the dimensional tolerance of the horizontal plate 1. The process involves vertically aligning and welding the ends of riser 2 to one side of horizontal plate 1. The welding current and speed are controlled throughout the welding process to reduce initial deformation caused by uneven heat input. After welding, horizontal plate 1 is left to cool completely naturally to eliminate temporary deformation caused by the instantaneous high temperature during welding. Then, the horizontal plate 1 and riser 2 are flipped and rotated to collect various dimensional data such as flatness, outer diameter, and coaxiality of horizontal plate 1 from all angles. The data are compared with the standard tolerance range of the drawings, and the locations of deviations, the magnitude of deformation, and the type of deformation (wavy warping, circumferential twisting, local bulges and depressions) are recorded.

[0026] S2. If the measured dimensions of the horizontal plate 1 exceed the standard tolerance range, mark the heating area 3 and the two types of heating paths on the surface of the horizontal plate 1. Specifically, taking the weld of riser 2 as a reference, the first heating path 4 is drawn on the surface of horizontal plate 1 away from riser 2; combined with the actual deformation distribution of the plate surface, the heating area 3 is drawn in the area between the first heating path 3 and the outer periphery of horizontal plate 1, and the lines clearly distinguish the heating boundary and the non-heating protection area to avoid the correction deviation caused by the ambiguity of the heating range.

[0027] S3. Correct the area to be heated 3 by using a combination of point heating and surface heating; Specifically, for single-point protrusions and local wavy deformation points within the area to be heated 3, a point heating process is used for targeted baking, relying on local high-temperature shrinkage to eliminate single-point concave-convex defects; for large-scale distortion and overall warping deformation of the entire area, a surface heating process is used, with the flame sweeping back and forth at a uniform speed within the designated area, so that the entire area to be heated 3 is heated synchronously and evenly, relying on overall thermal shrinkage to correct large-scale distortion of the board surface, first coarsely adjusting the overall deformation, and then finely correcting local single-point defects.

[0028] S4. After the heated area 3 has cooled naturally to room temperature, remeasure the dimensions and compare them with the standard dimensions. After point and surface composite heating is completed, the workpiece is left to cool naturally. Forced cooling methods such as water cooling and air cooling are prohibited to prevent thermal stress and cracks from forming on the horizontal plate 1. After cooling, all dimensions of the horizontal plate are measured again and compared with the standard tolerances in the drawings to judge the correction effect of overall warping and local single-point deformation. If there are still dimensional deviations, the next step of line heating fine correction process is carried out.

[0029] S5. Perform fine-tuning of the heating path along the symmetrically arranged heating path: Among them, on the plate surface of the horizontal plate 1 away from the riser 2, a reference circle 6 and a center 7 are drawn with the weld center of the riser 2 as the reference. The symmetrical points on the circumference of the reference circle 6 are used as the starting points of line heating. The flame moves at a constant speed towards the center 7 along the radial direction of the reference circle 6 to complete the radial line heating. More specifically, linear heating is first carried out along the first pre-marked heating path 4: an initial heating point is selected in the first heating path 4, and the flame is moved at a constant speed along the path from this point. The heating area 3 is straightened as a whole through long strip thermal contraction. The first heating path 4 coincides with the reference circle 6 in the circumference, that is, the weld of the riser 2 is heated by flame.

[0030] At the same time, such as Figure 2 As shown, in the preferred embodiment 1, two sets of symmetrical points are selected along the circumference of the reference circle 6 as the starting points for line heating, for a total of 4 starting points. The included angle between adjacent starting points on the circumference is 90 degrees, forming four second heating paths 5. The four second heating paths 5 are respectively directed radially towards the center 7 of the reference circle 6, and are uniformly heated on the surface of the horizontal plate 1. As the flame moves from the circumference of the reference circle 6 to the center 7, the flame heating width is widened synchronously, that is, the heating width of the second heating path 5 gradually increases from the outside to the center, adapting to the circumferential gradual deformation.

[0031] like Figure 3 As shown, in the preferred embodiment 2, three sets of symmetrical points are selected along the circumference of the reference circle 6 as the starting points for line heating, for a total of 6 starting points. The included angle between adjacent starting points on the circumference is 60 degrees, forming six second heating paths 5. The six second heating paths 5 are respectively directed radially towards the center 7 of the reference circle 6, and are uniformly heated on the surface of the horizontal plate 1. As the flame moves from the circumference of the reference circle 6 to the center 7, the heating width of the second heating path 5 gradually increases.

[0032] like Figure 4 As shown, in the preferred embodiment 3, five sets of symmetrical points are selected along the circumference of the reference circle 6 as the starting points for line heating, for a total of 10 starting points. The included angle between adjacent starting points on the circumference is 36 degrees, forming ten second heating paths 5. The ten second heating paths 5 are respectively directed radially towards the center 7 of the reference circle 6, and are uniformly heated on the surface of the horizontal plate 1. As the flame moves from the circumference of the reference circle 6 to the center 7, the heating width of the second heating path 5 gradually increases.

[0033] In other embodiments, the circumferential interval angle between two adjacent second heating paths 5 can be flexibly adjusted according to the actual deformation at different positions of the reference circle 6; the path angle is reduced and the heating trajectory is densified in areas with large deformation and serious deviation; the angle is increased and the heating lines are reduced in areas with slight deformation, so as to achieve differentiated and precise heating correction in different areas.

[0034] This method can match different deformation requirements in various places, avoid excessive local heat input causing the horizontal plate 1 to overheat, and also prevent insufficient heating from causing rework during correction. It can greatly improve the correction accuracy, reduce repeated heating processes, and effectively avoid defects such as lateral twisting and thermal cracking of the plate during the correction process.

[0035] S6. After all heating paths have cooled naturally, check the overall levelness of the control circle 6. After the second heating path 5 is completed, the workpiece is allowed to cool naturally to room temperature. Rigid limiting blocks 8 are installed at both ends of the horizontal plate 1 on the side away from the vertical pipe 2. The standard line 9 is pulled between the two limiting blocks 8. By measuring the vertical distance between each point on the reference circle 6 and the standard line 9, the height deviation of each point on the reference circle 6 is quantitatively judged. This is used to evaluate whether the overall levelness meets the standard. If the deviation still exceeds the allowable range, step S5 can be repeated to fine-tune the heating path angle and heating width for correction.

[0036] In addition, this application includes the following heating process control requirements: Temperature detection specifications: The operating temperature of point heating, surface heating and line heating is collected in real time by directly contacting the heated surface of the horizontal plate with a temperature measuring instrument. The interval between two adjacent temperature measurements shall not exceed 2 minutes. The heating temperature of the plate surface shall be controlled not to exceed 500℃ throughout the process to prevent the metallographic structure of the plate from deteriorating and the strength from decreasing due to high temperature.

[0037] Among them, point heating involves the flame baking a small local area of ​​the horizontal plate at a fixed point, with concentrated heating at a single point, which is used to correct local deformation at a single point; surface heating involves the flame moving back and forth within a defined area to form a whole heated surface, with large-area synchronous heating to correct the overall warping of the plate; and line heating involves the flame moving at a uniform speed along a preset radial path to form a strip heating band, with the heating width adjustable in a gradient, to specifically correct circumferential deformation.

[0038] Flame operation distance specifications: During operation, the flame peak inside the flame should maintain a fixed distance of 8~10mm from the surface of the horizontal plate. At the same time, the minimum distance between the flame heating area and the weld of riser 2 should not be less than 15mm to avoid direct burning of the weld by high temperature and to prevent the weld from softening due to tempering and the reduction of weld strength.

[0039] Based on the horizontal plate welding deformation flame adjustment method, the heating area of ​​this invention is subjected to balanced force, and the cooling and contraction are synchronized. The correction process is less prone to lateral twisting and displacement, resulting in higher correction accuracy.

[0040] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for adjusting the flame deformation during welding of a horizontal plate, characterized in that, The main steps include: S1. After the horizontal plate and the riser assembly are welded together, measure the dimensional tolerances of the horizontal plate. S2. If the final dimensions of the water platform are not within the specified range, mark the area to be heated and the path to be heated along the surface of the horizontal plane. S3. Correct the area to be heated by using point heating and surface heating methods; S4. After the area to be heated has cooled naturally, measure it again and compare it with the specified dimensions; S5. Correction is performed along the symmetrical path to be heated by line heating. Among them, a reference circle and its center are drawn on the surface of the horizontal plate away from the riser, corresponding to the weld at the riser port. The symmetrical point on the circumference of the reference circle is taken as the starting point of the line heating, and the line heating is carried out uniformly on the surface of the horizontal plate along the radius of the reference circle towards the center. S6. After the heated path has cooled naturally, remeasure the levelness of the reference circle.

2. The method for adjusting the welding deformation flame of a horizontal plate according to claim 1, characterized in that, In S1, the end of the riser is vertically welded to one side of the horizontal plate. After the horizontal plate cools naturally, the assembled riser and horizontal plate are rotated as a whole.

3. The method for adjusting the welding deformation flame of a horizontal plate according to claim 1, characterized in that, In S2, a first heating path is drawn along the welding position on the side of the horizontal plate away from the riser, and a heating area is drawn along the circumference of the horizontal plate and between the first heating path.

4. The method for adjusting the welding deformation flame of a horizontal plate according to claim 1, characterized in that, In S3, point heating is applied to the wave deformation within the heating area, and surface heating is used to adjust the torsional deformation of the heating area.

5. The method for adjusting the welding deformation flame of a horizontal plate according to claim 1 or 3, characterized in that, In S5, an initial heating point is selected on the first path to be heated, and the first path to be heated is heated at a constant speed starting from the initial heating point to straighten the entire area to be heated.

6. The method for adjusting the welding deformation flame of a horizontal plate according to claim 1, characterized in that, In S5, two sets of symmetrical points are selected along the circumference of the reference circle as the starting points for line heating. The four starting points are spaced 90 degrees apart on the circumference to form four second heating paths. The four second heating paths are respectively radially toward the center of the reference circle and are uniformly heated on the horizontal plate surface.

7. The method for adjusting the welding deformation flame of a horizontal plate according to claim 6, characterized in that, As the heating process proceeds from the radius of the reference circle toward the center line, the heating width of the second path to be heated gradually increases.

8. The method for adjusting the welding deformation flame of a horizontal plate according to claim 1, characterized in that, The heating temperature for point heating, surface heating, and line heating must be measured on the surface of the horizontal plate being heated, and the measurement interval should not exceed 2 minutes to ensure that the temperature of the heating area does not exceed 500 degrees Celsius.

9. The method for adjusting the welding deformation flame of a horizontal plate according to claim 8, characterized in that, The flame crest of the inner flame should be kept 8-10 mm from the surface of the horizontal plate and at least 15 mm from the weld.

10. The method for adjusting the welding deformation flame of a horizontal plate according to claim 1, characterized in that, In S6, limit blocks are set at both ends of the horizontal plate away from the riser, and a standard line is connected between the limit blocks. The levelness is judged by measuring the distance between each position of the reference circle and the standard line.

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