A Deformation Suppression Method for Transformer Tanks with Different Foundations

Abstract

This invention belongs to the field of power equipment installation and foundation construction, and mainly relates to a method for analyzing and suppressing deformation of high-voltage reactor transformer tanks under different foundations. Its features include: comparing multiple measurement methods, using an infrared level or a horizontal level to detect the flatness of the foundation; simulating the deformation of the tank under different foundation conditions and determining the standard deviation; adjusting the flatness of foundations exceeding the standard deviation to suppress tank deformation; and installing and fixing the tank on the adjusted foundation. This application uses a combined infrared level and horizontal level method, significantly improving measurement accuracy and avoiding misjudgments due to detection errors; adjusting the flatness of different foundations solves the problem of vibration amplification caused by uneven foundations; and proposing the establishment of a standard deviation for tank deformation, thus unifying industry standards.

Description

Technical Field

[0001] This invention relates to the field of power equipment installation and foundation construction, and in particular to a method for analyzing and suppressing deformation of transformer oil tanks in high-voltage reactors with different foundations. Background Technology

[0002] With the large-scale construction of global ultra-high voltage (UHV) transmission networks, UHV transformers and reactors, as core power grid transmission and transformation equipment, have reached single-unit capacities of 320,000 kVA and above (such as the BKDF-320000 / 1000 type reactor), with a total weight exceeding 340,000 kg. These devices exhibit significant vibration characteristics. The foundation, as the core load-bearing structure, directly determines the degree of fit between the equipment and the foundation, thus affecting the vibration amplitude during equipment operation. An uneven foundation can lead to partial unsupported sections of the equipment enclosure, significantly increasing the vibration amplitude of the enclosure walls compared to a well-supported state. Long-term operation can easily cause structural fatigue, sealing failures, and other malfunctions, even threatening power grid safety. Currently, the industry's demand for controlling the flatness of UHV equipment foundations continues to grow with increasing equipment capacity, but the lack of unified testing methods and deviation standards has become a key bottleneck restricting the quality of equipment installation. Summary of the Invention

[0003] To address the above problems, this invention proposes a method for analyzing and suppressing deformation of transformer tanks with different foundations for high-voltage reactors. It proposes to establish a standard for tank deformation and adjust the flatness of the foundation that exceeds the standard deviation, thereby effectively suppressing tank deformation.

[0004] This application proposes a method for analyzing and suppressing deformation of transformer tanks with different foundations, including the following steps: By comparing various measurement methods, the flatness of the foundation was tested using either an infrared level or a water level. The deformation of the fuel tank under different foundation conditions was simulated, and the standard deviation was determined. For foundations exceeding the standard deviation, perform flatness adjustments to suppress fuel tank deformation. Install and fix the oil tank after the flatness has been adjusted.

[0005] Furthermore, the infrared level measurement method includes the following steps: Equipment calibration: Place the infrared level on the standard platform. After the bubble stabilizes, set the left end reading to 0. Rotate 180°. The zero-position error is A / 2 divisions. Adjust the level to reduce the error to the permissible range. On-site measurement: Determine the length and width of the foundation as the test direction, place the working surface of the level against the foundation surface, and read the deviation number after the bubble stops moving. Segmented measurement: Measure in segments along the length and width directions, record the deviation values ​​of each segment, plot the error coordinate graph, and obtain the local maximum deviation.

[0006] Furthermore, the leveling instrument measurement method includes the following steps: Equipment installation: Adjust the support frame to chest height, level and fix the frame head, and install the level instrument using the connecting bolts; Calibration: Rotate the foot screws in opposite directions to center the bubble in the circular level, aim at the leveling rod, and then focus to eliminate parallax. Rotate the micro-tilt screw to match the half-image of the bubble in the level tube. Measurement: Divide the surface of the foundation to be measured into a grid, measure the elevation reading of each grid point, and calculate the relative height difference between the grid points as the flatness of the foundation.

[0007] Furthermore, the simulation demonstrates deformation under different basic conditions, including the following steps: Model creation: Simplify the internal structure of the fuel tank into mass points and create a model of the fuel tank shell; build models of the bottom of the fuel tank under different basic conditions; Build dynamic models under different basic conditions: constrain the bottom plate of the fuel tank and apply its own weight to simulate and analyze different basic conditions at the bottom of the fuel tank; Standard deviation determination: The standard deviation of the tank deformation is determined based on the maximum deformation of the tank bottom under different foundation conditions.

[0008] Furthermore, the different basic conditions include complete contact, partial contact, and central suspension.

[0009] Furthermore, the standard deviation for different basic conditions is taken as the maximum deformation at the bottom of the oil tank.

[0010] Furthermore, when building the dynamic model, a fixed constraint is applied to the bottom contact surface of the oil tank, and a gravitational acceleration is applied to the oil tank as a whole.

[0011] Furthermore, the adjustment of basic flatness includes overall adjustment and regional adjustment. The overall adjustment involves adding vibration isolation pads between the bottom of the oil tank and the foundation. The area adjustment involves clearing local depressions in the foundation and fixing the leveling plate to the depressions.

[0012] Furthermore, the vibration isolation pad is made of rubber, and the height of the vibration isolation pad is the same as the height of the foundation.

[0013] Furthermore, when installing the fuel tank, the leveling plate is made of steel.

[0014] The beneficial effects of this invention are as follows: Significantly improved detection accuracy: Compared with the traditional ruler and feeler gauge method and the string method, the infrared level and level instrument method used in this invention are combined to detect the problem, which greatly improves the measurement accuracy and avoids misjudgment caused by detection errors. Effective control of equipment vibration: This invention adjusts the flatness of different foundations to suppress excessive deformation of the oil tank, thereby reducing the vibration amplitude of the equipment and completely solving the problem of vibration amplification caused by uneven foundations; Industry standardization: Propose the formulation of fuel tank deformation standards to meet the needs of most manufacturers. On-site construction does not require process adjustments due to differences between manufacturers, thereby improving the installation qualification rate and shortening the construction period. Controllable construction costs: Reduces equipment maintenance costs due to uneven foundations, resulting in significant economic benefits. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A flowchart illustrating a method for analyzing and suppressing deformation of transformer tanks with different foundations, provided in an embodiment of this application; Figure 2 A schematic diagram of the simulation process in a method for analyzing and suppressing deformation of transformer tanks with different foundations provided in an embodiment of this application; Figure 3 A schematic diagram of the foundation flatness adjustment process in a method for analyzing and suppressing deformation of transformer tanks with different foundations provided in this application embodiment; Figure 4 A schematic diagram of foundation flatness detection in a method for analyzing and suppressing deformation of transformer tanks with different foundations provided in an embodiment of this application; Figure 5 A schematic diagram of the tank dynamic model in the simulation of a method for analyzing and suppressing deformation of transformer tanks with different foundations provided in an embodiment of this application; Figure 6 A schematic diagram illustrating the contact between different foundations and the oil tank in a deformation analysis and suppression method for high-voltage reactor transformer oil tanks with different foundations, provided in an embodiment of this application; Figure 7 This is a schematic diagram of the installation of the oil tank in a method for analyzing and suppressing deformation of the oil tank of a high-voltage reactor transformer with different foundations, provided in an embodiment of this application. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other implementations obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. In the various drawings, the same elements are represented by the same or similar reference numerals, and for clarity, the various parts in the drawings are not drawn to scale.

[0018] See Figure 1-7 As shown, this invention proposes a method for analyzing and suppressing deformation of transformer tanks with different foundations, comprising the following steps: S1. Compare various measurement methods and use infrared level or water level to detect the flatness of the foundation; See Figure 4 As shown, specifically, in step S1, the infrared level measurement method S11 includes the following steps: S111 Equipment calibration: Place the infrared level on the standard platform. After the bubble stabilizes, set the left end reading to 0. Rotate 180°. Formula 1: "Zero position error = A / 2 divisions". Adjust the level to reduce the error to the permissible range. S112. On-site measurement: Determine the length and width of the foundation as the test direction, place the working surface of the level against the foundation surface, and read the deviation number after the bubble stops. Calculate according to Formula 2: "Actual tilt value = 0.02mm / m × measurement length × deviation number". S113. Segmented measurement: Measure in segments along the length and width directions, record the deviation values ​​of each segment, draw an error coordinate graph, and obtain the local maximum deviation.

[0019] Specifically, in step S1, the leveling instrument measurement method S12 includes the following steps: S121. Equipment installation: Adjust the bracket to chest height and fix it horizontally. Install the level instrument using connecting bolts. S122. Calibration: Rotate the foot screws in opposite directions to center the bubble of the circular level, aim at the leveling rod and then focus to eliminate parallax. Rotate the micro-tilt screw to make the half-image of the bubble in the level tube match. S123. Measurement: Divide the surface of the foundation to be measured into a grid, measure the elevation reading of each grid point, and calculate the relative height difference between the grid points as the flatness of the foundation.

[0020] S2. Simulate the deformation of the oil tank under different foundation conditions and determine the standard deviation; See Figure 2As shown, specifically, in step S2, the simulation of deformation under different basic conditions includes the following steps: S21. Model Creation: Simplify the internal structure of the fuel tank into mass points and create a model of the fuel tank shell; build models of the bottom of the fuel tank under different basic conditions; S22. Build dynamic models under different basic conditions: constrain the bottom plate of the fuel tank and apply its own weight to simulate and analyze different basic conditions at the bottom of the fuel tank. See Figure 5 As shown, specifically, when building the dynamic model, a fixed constraint is applied to the bottom contact surface of the oil tank, and a gravitational acceleration is applied to the entire oil tank; S23. Standard deviation determination: Based on the maximum deformation of the bottom of the oil tank under different foundation conditions, determine the standard deviation of the oil tank deformation; In this embodiment, specifically, the standard deviation of different basic conditions is taken as the maximum deformation at the bottom of the oil tank, and the standard deviation of the oil tank deformation is determined to be ≤3mm.

[0021] See Figure 6 As shown, specifically, the different foundation conditions include complete contact, partial contact, and central suspension. In this embodiment, complete contact means that the entire bottom of the tank bears the force; partial contact means that a pre-embedded plate is embedded at the bottom of the tank, and the tank is placed on the pre-embedded plate, which is the only contact point between the tank and the foundation; central contact means that the bottom of the tank is in contact around the perimeter, with the interior suspended, to simulate the support state of local unevenness in the foundation.

[0022] S3. Adjust the flatness of the foundation if it exceeds the standard deviation to suppress oil tank deformation: See Figure 4 As shown, in this embodiment, if the elevation deviation of a certain grid point is found to be -3.5mm, exceeding the standard, the following adjustment measures will be taken: S31. Deviation Location: Mark the deviation area where the grid point is located with a marker; S32. Flatness adjustment, including overall adjustment and area adjustment; the overall adjustment and the area adjustment, S321. Area Adjustment: Clean up any low-lying areas of the foundation and fix the leveling plate to the low-lying areas to ensure the upper surface of the steel plate is flat. Specifically, when installing the fuel tank, the leveling plate is made of steel.

[0023] S322. Overall Adjustment: Vibration isolation pads are added between the leveled foundation and the overall foundation surface and the bottom of the oil tank, with no seams. Preferably, the vibration isolation pads are made of rubber, and their height is the same as the foundation height.

[0024] S4. Install and fix the oil tank after the flatness has been adjusted.

[0025] The following is a specific embodiment provided in this application: S1. Inspect the flatness of the base; S11. Using an infrared level for detection: S111 Equipment calibration: Place the infrared level on the standard platform. After the bubble stabilizes, set the reading on the left end to 0. After rotating 180°, the reading A = 0.02 divisions. Calculate according to Formula 1 to get 0.01 divisions, which is within the permissible range. S112. On-site measurement: Determine the foundation length (7.2m) and width (3.6m) as the test direction, place the working surface of the level against the foundation surface, and read the deviation number after the bubble stops moving. Calculate according to Formula 2. S113. Segmented measurement: Divide the length direction into 1m segments (8 segments in total) and the width direction into 1m segments (4 segments in total). Record the deviation value of each segment, draw an error coordinate graph, and find that the local maximum deviation is +2.8mm.

[0026] S12. Use a level instrument for testing: S121. Equipment installation: Spread the tripod to chest height, make the tripod head roughly horizontal and step on it to fix it firmly, and install the level instrument by connecting bolts; S122. Leveling and aiming: Rotate the foot screws in opposite directions to center the bubble of the circular level (rough leveling), aim at the leveling rod and then focus to eliminate parallax, rotate the micro-tilt screw to make the half-image of the bubble in the level tube match (fine leveling). S123. Grid Measurement: Divide the foundation surface into a 2m × 2m grid (4 rows and 2 columns, 8 grid points). Mark each grid point and measure the elevation values ​​sequentially: 100.002m, 100.003m, 100.001m, 100.000m, 99.999m, 100.001m, 99.998m, 100.000m; Elevation difference calculation: Connect adjacent grid points with dashed lines and mark the relative elevation difference (e.g., mark +0.001m between 100.002m and 100.003m). The overall maximum relative elevation difference is +2.9mm.

[0027] S2. Simulate the deformation of the oil tank under different foundation conditions and determine the standard deviation; Specifically, in step S2, the simulation of deformation under different basic conditions includes the following steps: S21. Model Creation: Simplify the internal structure of the fuel tank into mass points and create a model of the fuel tank shell; build models of the bottom of the fuel tank under different basic conditions; S22. Build dynamic models under different basic conditions: constrain the bottom plate of the fuel tank and apply its own weight to simulate and analyze different basic conditions at the bottom of the fuel tank. S23. Standard deviation determination: Based on the deformation of the bottom of the oil tank under different foundation conditions, the standard deviation of the oil tank deformation is determined to be ≤3mm.

[0028] Upon inspection, the maximum local deviation of the foundation was 2.8mm and the maximum relative height difference was 2.9mm, both of which meet the core standard of "≤±3mm" of this invention. Furthermore, the deviation of the embedded steel plate was verified to be -2mm, requiring no additional leveling or adjustment.

[0029] S3. Adjust the flatness of the foundation if it exceeds the standard deviation to suppress oil tank deformation: S31, Deviation Location: Mark the deviation area where the grid point is located; S32, Flatness Adjustment: S321. Area Adjustment: Select a 3.5mm thick Q345 thin steel plate, cut it into a shape that matches the deviation area, and use it as the leveling plate. Fix the leveling plate to the foundation surface with epoxy resin adhesive, and ensure that the upper surface of the leveling plate is flat. S322. Overall Adjustment: On the leveled foundation and the overall foundation surface, lay a 5mm thick vibration isolation pad to fully cover the surface.

[0030] S4. Install and fix the oil tank on the basis of the flatness adjustment; See Figure 7 As shown, the bottom of the oil tank and the embedded plate are filled with vibration damping pads, so that the bottom of the oil tank and the embedded plate are on the same plane. The oil tank is placed on top of the vibration damping pads. A pressure iron is set at the protruding part of the bottom of the oil tank, and the pressure iron presses the oil tank from above and is fixed to the pressure iron with bolts. The pressure iron is welded to the embedded plate around its perimeter. Preferably, when installing the oil tank, the radiator, oil tank and other accessories of the oil tank need to be cleaned to ensure that there is no black dirt on the installation parts of the accessories; and the elevation difference between the embedded plate and the main body foundation is checked. In this embodiment, the elevation difference is +0.5mm, which meets the requirement of ≤±1mm; and the inside of the oil tank is inspected. In a dry air environment with a dew point of -50℃, after the reactor is purged with nitrogen, the oxygen content in the oil tank is tested to be ≥19.5%, confirming that there is no displacement of the reactor body and the insulation resistance is qualified; after the oil tank is installed, the vibration amplitude of the tank wall is tested to be 0.09mm, which meets the low vibration operation requirements.

[0031] The beneficial effects of this invention are as follows: Significantly improved detection accuracy: Compared with the traditional ruler and feeler gauge method and the string method, the infrared level and level instrument method used in this invention are combined to detect the problem, which greatly improves the measurement accuracy and avoids misjudgment caused by detection errors. Effective control of equipment vibration: This invention adjusts the flatness of different foundations to suppress excessive deformation of the oil tank, thereby reducing the vibration amplitude of the equipment and completely solving the problem of vibration amplification caused by uneven foundations; Industry standardization: Propose the formulation of fuel tank deformation standards to meet the needs of most manufacturers. On-site construction does not require process adjustments due to differences between manufacturers, thereby improving the installation qualification rate and shortening the construction period. Controllable construction costs: Reduces equipment maintenance costs due to uneven foundations, resulting in significant economic benefits.

[0032] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be noted that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0033] Those skilled in the art will understand that, unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose. The step numbers used in this specification are for distinguishing steps only and are not intended to limit the temporal or logical relationship between steps, and the relationship between steps includes a wide range of possibilities unless expressly defined herein.

[0034] It should be noted that the above embodiments are illustrative of this disclosure and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. Finally, it should be noted that the above embodiments are clearly examples for clearly illustrating the invention and are not intended to limit the implementation. 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. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for analyzing and suppressing deformation of transformer tanks with different foundations, characterized in that, Includes the following steps: By comparing various measurement methods, the flatness of the foundation was tested using either an infrared level or a water level. The deformation of the fuel tank under different foundation conditions was simulated, and the standard deviation was determined. For foundations exceeding the standard deviation, perform flatness adjustments to suppress fuel tank deformation. Install and fix the oil tank after the flatness has been adjusted.

2. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 1, characterized in that, The infrared level measurement method includes the following steps: Equipment calibration: Place the infrared level on a standard platform. After the bubble stabilizes, set the left end reading to 0, then rotate 180°. The error was reduced to within acceptable limits through adjustments; On-site measurement: Determine the length and width of the foundation as the test direction, place the working surface of the level against the foundation surface, and read the deviation number after the bubble stops moving. Segmented measurement: Measure in segments along the length and width directions, record the deviation values ​​of each segment, plot the error coordinate graph, and obtain the local maximum deviation.

3. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 1, characterized in that, The leveling instrument measurement method includes the following steps: Equipment installation: Adjust the support frame to chest height, level and fix the frame head, and install the level instrument using the connecting bolts; Calibration: Rotate the foot screws in opposite directions to center the bubble in the circular level, aim at the leveling rod, and then focus to eliminate parallax. Rotate the micro-tilt screw to match the half-image of the bubble in the level tube. Measurement: Divide the surface of the foundation to be measured into a grid, measure the elevation reading of each grid point, and calculate the relative height difference between the grid points as the flatness of the foundation.

4. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 1, characterized in that, Simulation of deformation under different basic conditions includes the following steps: Model creation: Simplify the internal structure of the fuel tank into mass points and create a model of the fuel tank shell; build models of the bottom of the fuel tank under different basic conditions; Build dynamic models under different basic conditions: constrain the bottom plate of the fuel tank and apply its own weight to simulate and analyze different basic conditions at the bottom of the fuel tank; Standard deviation determination: The standard deviation of the tank deformation is determined based on the maximum deformation of the tank bottom under different foundation conditions.

5. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 1, characterized in that, The different basic conditions include complete contact, partial contact, and central suspension.

6. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 1, characterized in that, The standard deviation for different basic conditions is taken as the maximum deformation at the bottom of the oil tank.

7. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 4, characterized in that, When building the dynamic model, a fixed constraint is applied to the bottom contact surface of the oil tank, and a gravitational acceleration is applied to the entire oil tank.

8. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 1, characterized in that, Basic flatness adjustment includes overall adjustment and regional adjustment. The overall adjustment involves adding vibration isolation pads between the bottom of the oil tank and the foundation. The area adjustment involves clearing local depressions in the foundation and fixing the leveling plate to the depressions.

9. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 8, characterized in that, The vibration isolation pad is made of rubber, and its height is the same as that of the foundation.

10. The method for analyzing and suppressing deformation of transformer tanks with different foundations according to claim 8, characterized in that, When installing the fuel tank, the leveling plate is made of steel.

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