A system and method for testing the ultimate thickness of a tank bottom ring wall panel

Abstract

This invention discloses a test system and method for the ultimate thickness of the bottom ring wall plate of a storage tank. The system includes a simulated storage tank, a bottom ring wall plate, a pressurizing device, and a stress sensor. The simulated storage tank includes a tank wall, a tank bottom, and a floating roof. The floating roof is disposed inside the tank and connected to the inner wall of the tank wall to form a partially sealed structure. The bottom of the simulated tank is welded to the bottom ring wall plate. The pressurizing device is disposed above the floating roof of the simulated tank to simulate the pressure on the bottom ring wall plate during actual production and operation. The stress sensor is installed on the outer wall of the tank wall to detect the stress on the tank. This invention determines the ultimate thickness of the bottom ring wall plate through experiments, saving materials while meeting the required thickness of the bottom ring wall plate. It can save steel and reduce costs while ensuring the safe operation of the storage tank, resulting in significant economic benefits.

Description

Technical Field

[0001] This invention relates to the field of chemical storage technology, and in particular to a test system and method for the ultimate thickness of the bottom ring wall plate of a storage tank. Background Technology

[0002] With rapid economic development, oil resources continue to play an irreplaceable supporting role. To prevent oil supply shortages or disruptions due to extreme circumstances, the country is accelerating the construction of large-scale strategic oil reserve bases. Large storage tanks, as crucial oil storage equipment, require significant investment of manpower, materials, and financial resources during construction. In particular, the tank walls are currently mostly made of SPV490Q steel, which needs to be imported and is relatively expensive. The tank wall thickness is usually determined through experience and calculations, which can deviate from the actual required thickness, often resulting in steel waste.

[0003] To address the discrepancy between the thickness of the tank wall panels and the actual required thickness, an experimental system was designed to determine the limit thickness of the tank bottom ring wall panels. Summary of the Invention

[0004] The purpose of this invention is to provide a test system and method for the ultimate thickness of the bottom ring wall plate of a storage tank. This test system can determine the ultimate thickness of the bottom ring wall plate of the storage tank, which can save materials, avoid waste, save time, and save a lot of money for enterprises.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A test system for the ultimate thickness of the bottom ring wall plate of a storage tank, the system comprising a simulated storage tank, a bottom ring wall plate of the storage tank, a pressurization device, and a stress sensor, wherein...

[0007] The simulated storage tank includes a tank wall, a tank bottom, and a floating roof; the floating roof is located inside the tank and is connected to the inner wall of the tank wall to form a regionally sealed structure.

[0008] The simulated storage tank bottom is welded to the storage tank bottom ring wall plate;

[0009] The pressurization device is installed above the floating roof of the simulated storage tank to simulate the pressure on the bottom ring wall of the storage tank during actual production and operation.

[0010] Stress sensors are installed on the outer wall of the storage tank to detect the stress experienced by the tank.

[0011] Preferably, the system also includes a basic platform;

[0012] The simulated storage tank is built on a base platform; the diameter of the base platform is larger than the diameter of the simulated storage tank.

[0013] Preferably, the gap between the floating roof and the inner wall of the storage tank is filled with nitrile rubber.

[0014] The thickness of the floating roof in the simulated storage tank is 2.5%-7.5% of the thickness of the actual production storage tank.

[0015] The design thickness of the bottom ring wall plate of the storage tank is obtained through calculation.

[0016] Preferably, the formula for calculating the thickness of the bottom ring wall plate of the storage tank is as follows:

[0017]

[0018] In the formula: t d - The calculated thickness of the bottom ring wall plate of the storage tank under the operating conditions of the stored medium, in mm;

[0019] D - Inner diameter of the storage tank;

[0020] H - Calculate the liquid level height, which is the height from the bottom of the calculated tank wall plate to the top of the tank wall edging angle steel;

[0021] ρ - relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water;

[0022] [σ] d - Allowable stress of the steel plate at the design temperature;

[0023] - Noise level of joint, taken as When the yield strength specified in the standard is greater than 390 MPa, the bottom ring tank wall should be...

[0024] Preferably, the formula for calculating the thickness of the tank bottom ring wall plate further includes:

[0025]

[0026] In the formula, δ 1d -Required thickness of the tank bottom ring wall plate;

[0027] D - Inner diameter of the storage tank;

[0028] H - Calculate the liquid level height;

[0029] ρ - relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water;

[0030] S d - Allowable stress of the steel plate under design conditions, MPa;

[0031] C1 - Corrosion allowance, taken as 1 mm.

[0032] Preferably, the gap between the floating roof and the inner wall of the storage tank is sealed with a nitrile rubber or other elastic material sealing structure.

[0033] Preferably, the pressurizing device includes, but is not limited to, any one of a pneumatic pressurizing device or a hydraulic pressurizing device.

[0034] Preferably, the stress sensor is installed on the outer wall of the storage tank, including,

[0035] Multiple stress sensors are installed at equal intervals on the outside of the tank wall;

[0036] The stress sensors are installed at points on the outside of the tank wall, from the bottom of the simulated tank to the corresponding height of the floating roof, with radial installation points spaced 50-100mm apart and circumferential installation points spaced 0.5-2m apart.

[0037] The designated points include those where the storage tank experiences high stress and is prone to deformation and cracking.

[0038] A method for testing the ultimate thickness of the bottom ring wall plate of a storage tank, the method comprising constructing simulated storage tanks with different bottom ring wall plate thicknesses, wherein the bottom ring wall plate of the storage tank is welded to the bottom of the simulated storage tank;

[0039] Based on the pressure exerted on the bottom ring wall of the storage tank during actual production and operation, different pressures are applied multiple times to the pressurization device on the floating roof of each simulated storage tank;

[0040] Record the values ​​corresponding to the stress sensors on the outer wall of each simulated storage tank under different pressures;

[0041] Based on the values ​​recorded by the stress sensor, the maximum stress value of each simulated storage tank is obtained;

[0042] The maximum stress value of each simulated tank is compared with the yield stress of the steel used in the tank bottom ring wall to determine the ultimate thickness of the tank bottom ring wall.

[0043] Preferably, the simulated storage tank is built on a base platform; the diameter of the base platform is larger than the diameter of the simulated storage tank.

[0044] Preferably, the thickness of the floating roof of the simulated storage tank is 2.5%-7.5% of the thickness of the actual production storage tank;

[0045] The thickness of the bottom ring wall plate of the storage tank is obtained through calculation.

[0046] Preferably, the formula for calculating the thickness of the tank bottom ring wall plate includes:

[0047]

[0048] In the formula: t d- The calculated thickness of the bottom ring wall plate of the storage tank under the operating conditions of the stored medium, in mm;

[0049] D - Inner diameter of the storage tank;

[0050] H - Calculate the liquid level height, which is the height from the bottom of the calculated tank wall plate to the top of the tank wall edging angle steel;

[0051] ρ - relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water;

[0052] [σ] d - Allowable stress of the steel plate at the design temperature;

[0053] - Noise level of joint, taken as When the yield strength specified in the standard is greater than 390 MPa, the bottom ring tank wall should be...

[0054] or,

[0055]

[0056] In the formula, δ 1d -Required thickness of the bottom panel;

[0057] D - Inner diameter of the storage tank;

[0058] H - Calculate the liquid level height;

[0059] ρ - relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water;

[0060] S d - Allowable stress of the steel plate under design conditions, MPa;

[0061] C1 - Corrosion allowance, taken as 1 mm.

[0062] Preferably, the step of comparing the maximum stress value with the yield stress of the steel to determine the thickness of the tank bottom ring wall includes:

[0063] When the maximum stress value is less than the yield stress of the corresponding steel, the thickness of the bottom ring wall plate (8) of the storage tank is qualified.

[0064] The technical effects and advantages of this invention are as follows:

[0065] This application addresses the problem that steel waste often results from determining the wall thickness based on experience and calculation in existing technologies. It designs an experimental system and method to determine the limit thickness of the bottom ring wall of a storage tank. By experimentally determining the limit thickness of the bottom ring wall, this method solves the problem of steel waste caused by the deviation between the thickness of the tank wall obtained through traditional calculation and experience and the actual required thickness. This saves manpower, material resources, and financial resources in the construction of storage tanks.

[0066] 1. Reliability. The ultimate thickness of the bottom ring wall plate, obtained through specific experimental results, is more reliable than the wall thickness obtained through experience and calculation.

[0067] 2. Feasibility. Conducting experimental research on simulated storage tanks can not only save a lot of experimental costs, but also accomplish experimental operations that are difficult or even impossible to achieve in actual storage tanks.

[0068] 3. Simplicity. The experimental system has a simple structure and is easy to operate. Compared to a complete actual storage tank, it simplifies many structural aspects without affecting the final experimental results.

[0069] 4. Wide applicability. The experimental system for determining the ultimate thickness of the bottom ring wall of a storage tank can be used not only to determine the ultimate thickness of the bottom ring wall, but also the ultimate thickness of the second, third, fourth, fifth, sixth, seventh, eighth, and ninth layers of wall, as well as the ultimate thickness of the tank wall under different storage media. It can also be applied to the determination of the ultimate wall thickness of various types of storage tanks, making it widely applicable.

[0070] 5. Economic efficiency. The greatest advantage of this experimental system is that it determines the limit thickness of the bottom ring wall plate of the storage tank through experiments. While meeting the required thickness of the bottom ring wall plate, it saves materials, thus saving steel and reducing costs while ensuring the safe operation of the storage tank, resulting in significant economic benefits.

[0071] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0072] Figure 1 This is a schematic diagram of a 100,000 cubic meter storage tank in a specific embodiment of the present invention;

[0073] Figure 2 This is a schematic diagram of an experimental system for determining the ultimate thickness of the bottom ring wall plate of a storage tank, according to a specific embodiment of the present invention.

[0074] Figure 3This is a cross-sectional schematic diagram of an experimental system for determining the ultimate thickness of the bottom ring wall plate of a storage tank in a specific embodiment of the present invention;

[0075] Figure 4 This is a schematic cross-sectional view of a 100,000 cubic meter storage tank in a specific embodiment of the present invention;

[0076] Figure 5 This is a schematic diagram of the floating roof of an experimental storage tank in a specific embodiment of the present invention.

[0077] In the diagram: 1-Top of the tank; 2-Floating roof; 3-Tank wall; 4-Bottom of the tank; 5-Foundation platform; 6-Pressure device; 7-Stress sensor; 8-Bottom ring wall plate of the tank. Detailed Implementation

[0078] 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, and 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.

[0079] To address the shortcomings of existing technologies, this invention discloses a test system and method for the ultimate thickness of the bottom ring wall plate of a storage tank. By experimentally determining the ultimate thickness of the bottom ring wall plate of the storage tank, this invention solves the problem of steel waste caused by the deviation between the thickness of the storage tank wall plate obtained through traditional calculations and experience and the actual required thickness. This saves manpower, material resources, and financial resources in the construction of storage tanks.

[0080] Figure 1 A schematic diagram of a 100,000 cubic meter storage tank is shown in a specific embodiment of the present invention. Figure 1 It is known that the simulated storage tank includes a tank top 1, a tank bottom 4, a tank wall 3, and a floating roof 2; wherein, the tank top 1, tank wall 3, and tank bottom 4 are connected in sequence; the tank bottom of the simulated storage tank is welded together with the tank bottom ring wall plate 8, and together they are built on the foundation platform 5; the floating roof 2 of the simulated storage tank is set inside the tank, and the floating roof 2 is connected to the inner wall of the tank wall 3. The gap between the floating roof 2 and the inner wall of the tank wall 3 is filled with nitrile rubber to form a regionally sealed structure.

[0081] Figure 2 and Figure 3 This invention illustrates a schematic diagram and cross-sectional view of an experimental system for determining the ultimate thickness of the bottom ring wall plate 8 of a storage tank, in accordance with a specific embodiment of the present invention. Figure 2 and Figure 3The system of this invention includes a base platform 5, a simulated storage tank, a tank bottom ring wall plate 8, a pressurizing device 6, and a stress sensor 7. These devices are connected sequentially to form a whole. The simulated storage tank includes a tank wall 3, a tank bottom 4, and a floating roof 2. The floating roof 2 is located inside the simulated storage tank and is connected to the inner wall of the tank wall 3. The gap between the floating roof 2 and the inner wall of the tank wall 3 is filled with nitrile rubber to form a partially sealed structure. The tank bottom 4 of the simulated storage tank is welded to the tank bottom ring wall plate 8. The pressurizing device 6 is located above the floating roof 2 of the simulated storage tank to apply pressure, simulating the pressure experienced by the tank bottom ring wall plate 8 during actual production operation. The stress sensor 7 is installed on the outer wall of the tank wall 3 to detect the magnitude of the stress experienced by the tank. It should be noted that during actual production operation, a sealing device is required to seal the inner wall of the tank wall 3 and the floating roof 2. To reduce the complexity and improve the accuracy of the experiment, it is necessary to reduce unnecessary interference devices. Instead of using a sealing device to seal the inner wall of the experimental tank and the floating plate 2, nitrile rubber is used directly for sealing.

[0082] Furthermore, the pressurizing device 6 includes, but is not limited to, any one of a pneumatic pressurizing device or a hydraulic pressurizing device.

[0083] Furthermore, the stress sensor 7 is installed on the outer wall of the simulated storage tank, including multiple stress sensors 7 installed at equal intervals on the outer wall of the simulated storage tank; the stress sensor 7 is set at the following positions on the outside of the tank wall 3: from the bottom of the simulated storage tank to the corresponding height of the floating roof 2, with radial setting points spaced at 50-100mm and circumferential setting points spaced at 0.5-2m; the setting points include points in the storage tank where the stress is high and deformation and cracking are likely to occur.

[0084] In one specific embodiment of the present invention, to ensure the accuracy of the results, for a simulated storage tank with a diameter of 4m, as many stress sensors 7 as possible are set up. Sensors are placed at points with higher stress in the radial direction of the tank. The selected locations are based on conclusions from previous experiments and simulations. Through these experiments and simulations, we can roughly determine which locations are likely to have higher stress and are prone to deformation and cracking. The number of sensors in the radial direction can be appropriately increased. The sensors in the circumferential direction serve a comparative purpose; two or four sensors can be placed around the circumference.

[0085] Furthermore, the thickness of the floating roof 2 of the simulated storage tank is 2.5%-7.5% of the thickness of the actual production storage tank; in one embodiment of the present invention, the design standard thickness of the floating roof of a 100,000 cubic meter storage tank is 1.5m, and the thickness of the floating roof according to similarity theory is 75mm.

[0086] Furthermore, the thickness of the bottom ring wall plate 8 of the storage tank is obtained through calculation, including calculating the thickness of the bottom ring wall plate according to national standards and the American API 650 standard.

[0087] Furthermore, according to national standards, the formula for calculating the thickness of the bottom ring wall plate 8 of the storage tank is as follows:

[0088]

[0089] In the formula: t d - Calculated thickness of tank wall plate under operating conditions of the stored medium, mm;

[0090] D - Inner diameter of the storage tank;

[0091] H - Calculate the liquid level height, which is the height from the bottom of the calculated tank bottom ring wall plate 8 to the top of the tank wall 3 edge angle steel;

[0092] ρ - relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water;

[0093] [σ] d - Allowable stress of the steel plate at the design temperature;

[0094] - Noise level of joint, taken as The design specifications generally stipulate a yield strength of 0.9. However, when the standard specifies a yield strength greater than 390 MPa, the bottom ring tank wall should be... or,

[0095] Calculations based on the US API 650 standard include:

[0096]

[0097] In the formula, δ 1d -Required thickness of tank bottom ring wall plate 8;

[0098] D - Inner diameter of the storage tank;

[0099] H - Calculate the liquid level height;

[0100] ρ - relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water;

[0101] S d - Allowable stress of the steel plate under design conditions, MPa;

[0102] C1 - Corrosion allowance, taken as 1 mm.

[0103] These two formulas are the national standard and the American API 650 standard for calculating the bottom ring wall plate. Both can be used to calculate the thickness of the bottom ring wall plate, and the final calculation results of the two standards are consistent. Using the two standards serves as a comparison and verification to check whether the calculation of one of the standards is reasonable. If the difference is too large, it proves that there is an error in the calculation process. If the difference is not large, the result calculated by the American API 650 standard shall be used.

[0104] This invention also discloses a method for testing the ultimate thickness of the bottom ring wall plate of a storage tank, the method comprising the following steps:

[0105] Construct simulated storage tanks with different bottom ring wall plate thicknesses;

[0106] Based on the pressure exerted on the bottom ring wall plate 8 of the storage tank during actual production and operation, different pressures are applied multiple times to the pressurization device 6 in each simulated storage tank;

[0107] Record the values ​​corresponding to stress sensor 7 on the outer wall of each simulated tank under different pressures;

[0108] Based on the values ​​recorded by the stress sensor 7, the maximum stress value of each simulated storage tank is obtained;

[0109] The maximum stress value of each simulated tank is compared with the yield stress of the steel to determine the thickness of the bottom ring wall plate of the tank. The bottom ring wall plate thickness of the simulated tank is qualified when the maximum stress value is less than the yield stress of the corresponding steel.

[0110] Furthermore, the simulated storage tank is built on top of the base platform 5; the diameter of the base platform 5 is larger than the diameter of the simulated storage tank.

[0111] The apparatus used in the above-mentioned method for testing the ultimate thickness of the bottom ring wall plate 8 of the storage tank, including the connection relationships and arrangement of the various devices, has been described in detail in the embodiments of the relevant system, and will not be elaborated here.

[0112] To further illustrate the technical solution of this application, the technical solution of the present invention will be further described below in conjunction with specific embodiments.

[0113] The thickness of the bottom ring wall plate was calculated based on national standards and the American API 650 standard. The mechanical properties of SPV490Q steel are: yield strength ≥490MPa for plate thicknesses between 6 and 50 mm. National Standard:

[0114]

[0115] In the formula: t d - Calculated thickness of tank wall plate under operating conditions of the stored medium, mm;

[0116] D - Inner diameter of the storage tank, in meters;

[0117] H - Calculated liquid level height, m, is the height from the bottom of the calculated tank wall plate to the top of the 3-sided angle steel of the tank wall.

[0118] ρ - Relative density of the storage liquid (the ratio of the density of the storage liquid to that of water);

[0119] [σ] d - Allowable stress of steel plate at design temperature, MPa;

[0120] - Noise level of joint, taken as When the yield strength specified in the standard is greater than 390 MPa, the bottom ring tank wall should be...

[0121] API 650 standard:

[0122]

[0123] δ 1d -Required thickness of the bottom panel, in mm;

[0124] D - Inner diameter of the storage tank, in meters;

[0125] H - Calculated liquid level height, in meters;

[0126] ρ - Relative density of the storage liquid (the ratio of the density of the storage liquid to that of water);

[0127] S d - Allowable stress of the steel plate under design conditions, MPa;

[0128] C1 - Corrosion allowance, taken as 1 mm.

[0129] The calculation can be performed by substituting the corresponding values ​​of the actual tank to be calculated. Here, we take a 100,000 cubic meter external floating roof tank as an example. The scale of the experimental tank and the prototype is 1 / 20. The diameter of the experimental tank is designed to be 4m, the diameter of the foundation platform 5 is 4.3m, the thickness of the floating roof 2 is 75mm, and the bottom ring wall is designed according to the actual height of 1.7m. Substituting the above actual values ​​into the formula, the thickness of the bottom ring wall can be calculated. The thickness of the bottom ring wall 8 of the tank is calculated to be 34mm using two standards.

[0130] Furthermore, based on similarity theory, combined with Figure 4It is known that an experimental simulated storage tank is constructed in the laboratory. The simulated storage tank includes a tank top 1, a tank wall 3, a tank bottom 4, and a floating roof 2; the tank top 1, tank wall 3, and tank bottom 4 are connected in sequence, the floating roof 2 is set inside the simulated storage tank, the floating roof 2 is connected to the inner wall of the tank wall 3, and the gap between the floating roof 2 and the inner wall of the tank wall 3 is filled with nitrile rubber to form a regionally sealed structure; the tank bottom 4 of the simulated storage tank is welded to the tank bottom ring wall plate 8 and together they are built on the foundation platform 5; a pressurizing device 6 is set above the floating roof 2 of the simulated storage tank to apply pressure, simulating the pressure on the tank bottom ring wall plate 8 during actual production operation; a stress sensor 7 is installed on the outer wall of the tank wall 3 to detect the magnitude of the stress on the tank. According to national standards, a 100,000 cubic meter storage tank has a height of 21.8m, a diameter of 80m, and a floating roof thickness of 1.5m. The scale of the experimental model compared to the prototype cannot be too large, resulting in excessive resource consumption and manufacturing costs, nor can it be too small, leading to a decrease in experimental accuracy. Considering factors such as funding, space, and result accuracy, a scale of 1 / 20 was chosen for the model compared to the prototype. Therefore, the diameter of the experimental storage tank was designed to be 4m, the diameter of the foundation platform 5 to be 4.3m, the thickness of the floating roof 2 to be 75mm, and the bottom ring wall panels to be designed according to an actual height of 1.7m; experimental storage tanks with bottom ring wall panel thicknesses of 34mm, 33mm, 32mm, 31mm, and 30mm were constructed.

[0131] Furthermore, in the experiment, the stress value of the outer wall of the bottom ring plate 8 of the storage tank was obtained by installing stress sensors 7 on the outer wall of the storage tank to obtain the stress value at different positions for different bottom ring plate thicknesses. The stress sensors 7 were installed at heights of 30mm, 100mm, 200mm, 400mm, 600mm, 800mm, 1000mm, 1100mm, 1200mm, 1300mm, 1400mm, 1500mm, and 1600mm from the bottom plate of the storage tank. To ensure the accuracy of the experiment, 2 to 4 sensors were installed at equal intervals along the circumference of the outer wall of the storage tank, for a total of 26 to 52 stress sensors 7.

[0132] Furthermore, the ultimate thickness of the bottom ring wall plate 8 of the storage tank was determined experimentally. The experimental storage tank was built on a cement platform, and a pressurizing device 6 was installed on the floating roof 2 to apply pressure. The applied pressure was F = PS, where P is the actual pressure exerted on the bottom ring wall plate 8 of the storage tank, p = ρ. 油The tank height is 21.8m, and the float plate 2 thickness is 1.5m. Therefore, the maximum liquid level is h = 21.8 - 1.5 = 20.3m. S is the area of ​​contact between the liquid surface and the inner wall of the tank (S = πdh). Nitrile rubber has good sealing performance, so the gap between the float plate 2 and the inner wall of the tank is sealed with nitrile rubber. At the beginning of the experiment, a pressure value is applied to the pressurizing device 6, and the pressure is slowly increased. After the pressure value reaches the set value, the value of the stress sensor 7 on the outer wall of the tank stabilizes. Then, the values ​​of the stress sensor 7 at each node are recorded, the maximum stress value is recorded, and compared with the yield stress of SPV490Q steel (the yield stress of steel is 490 MPa). If the stress is less than 490 MPa, we can consider that the thickness of the bottom ring wall plate of the tank meets the requirements. Through experiments, we found that when the thickness of the bottom ring wall plate is 34mm and 33mm, the value of stress sensor 7 is much lower than the yield stress of the steel. When the thickness of the bottom ring wall plate 8 is 32mm, the maximum value displayed by stress sensor 7 is close to the yield stress of the steel (490MPa), but still less than the yield stress of the steel. When the thickness of the bottom ring wall plate 8 is 31mm and 30mm, the maximum value displayed by stress sensor 7 is greater than the yield stress of the steel (490MPa), exceeding the yield stress of the steel. As the thickness of the bottom ring wall plate decreases, it gets closer to the yield stress of the steel. As long as the maximum value displayed by stress sensor 7 is less than the yield stress of the steel, it is safe. Therefore, we can conclude that the limit thickness of the bottom ring wall plate 8 of a 100,000 cubic meter storage tank is 32mm.

[0133] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A system for testing the ultimate thickness of a wall panel of a tank bottom ring, the system comprising: The system includes simulated storage tanks with different bottom ring wall plate (8) thicknesses, a pressurization device (6), and a stress sensor (7), wherein, The simulated storage tank includes a tank wall (3), a tank bottom (4), and a floating roof (2); the floating roof (2) is located inside the storage tank and is connected to the inner wall of the tank wall (3) to form a regionally sealed structure. The simulated tank bottom (4) is welded to the tank bottom ring wall plate (8); the design thickness of the tank bottom ring wall plate (8) is obtained by calculation; The pressurization device (6) is set above the floating roof (2) of the simulated storage tank to simulate the pressure on the bottom ring wall plate (8) of the storage tank during actual production and operation. The stress sensor (7) is installed on the outer wall of the tank wall (3) to detect the stress on the tank.

2. The system for testing the ultimate thickness of a wall panel of a tank bottom ring according to claim 1, characterized in that, The system also includes a basic platform (5); The simulated storage tank is built on top of the base platform (5); the diameter of the base platform (5) is larger than the diameter of the simulated storage tank.

3. The tank bottom ring wall plate ultimate thickness test system according to claim 1, characterized in that, The gap between the floating roof (2) and the inner wall of the storage tank (3) is filled with nitrile rubber. The thickness of the floating roof (2) of the simulated storage tank is 2.5%-7.5% of the thickness of the actual production storage tank.

4. The ultimate thickness test system for the bottom ring wall plate of a storage tank according to claim 3, characterized in that, The formula for calculating the thickness of the bottom ring wall plate (8) of the storage tank is as follows: In the formula: t d - Calculated thickness of the wall of the bottom ring of the tank in the operating conditions of the storage medium, mm D - Inner diameter of the storage tank; H - Calculate the liquid level height, which is the height from the bottom of the calculated tank wall plate to the top of the tank wall edging angle steel; - The relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water; - Allowable stress of the steel plate at the design temperature; - Noise level of joint, taken as When the yield strength specified in the standard is greater than 390 MPa, the bottom ring tank wall should be... ;or, In the formula, -Required thickness of the tank bottom ring wall plate; D - Inner diameter of the storage tank; H - Calculate the liquid level height; - The relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water; - Allowable stress of the steel plate under design conditions, MPa; - Corrosion allowance, take 1mm.

5. The tank bottom ring wall plate ultimate thickness test system according to claim 3, characterized in that, The gap between the floating roof (2) and the inner wall of the storage tank is sealed with a nitrile rubber or other elastic material sealing structure.

6. The ultimate thickness test system for the bottom ring wall plate of a storage tank according to claim 1, characterized in that, The pressurizing device (6) includes, but is not limited to, any one of a pneumatic pressurizing device or a hydraulic pressurizing device.

7. The ultimate thickness test system for the bottom ring wall plate of a storage tank according to claim 1, characterized in that, The stress sensor (7) is installed on the outer wall of the tank wall (3), including, Multiple stress sensors (7) are installed at equal intervals on the outside of the tank wall (3); The stress sensors (7) are set at points on the outside of the tank wall (3), including positions from the bottom of the simulated tank to the corresponding height of the floating roof (2), with radial point spacing of 50-100mm and circumferential point spacing of 0.5-2m; The designated points include those where the storage tank experiences high stress and is prone to deformation and cracking.

8. A method for testing the ultimate thickness of the bottom ring wall plate of a storage tank, characterized in that, The method employs the tank bottom ring wall plate ultimate thickness test system as described in any one of claims 1-7, the method comprising: Construct simulated storage tanks with different thicknesses of tank bottom ring wall plates (8), wherein the tank bottom ring wall plates (8) are welded to the tank bottom (4) of the simulated storage tank; Based on the pressure exerted on the bottom ring wall plate (8) of the storage tank during actual production and operation, different pressures are applied multiple times to the pressurizing device (6) on each of the simulated storage tank floating plates (2); Record the values ​​corresponding to the stress sensors (7) on the outer wall of each simulated tank under different pressures; Based on the values ​​recorded by the stress sensor (7), the maximum stress value of each simulated tank is obtained; The maximum stress value of each simulated tank is compared with the yield stress of the steel used in the bottom ring wall plate (8) of the tank to determine the ultimate thickness of the bottom ring wall plate of the tank.

9. The method for testing the ultimate thickness of the bottom ring wall plate of a storage tank according to claim 8, characterized in that, The simulated storage tank is built on top of the base platform (5); the diameter of the base platform (5) is larger than the diameter of the simulated storage tank.

10. The method for testing the ultimate thickness of the bottom ring wall plate of a storage tank according to claim 8, characterized in that, The thickness of the floating roof (2) of the simulated storage tank is 2.5%-7.5% of the thickness of the actual production storage tank; The thickness of the bottom ring wall plate (8) of the storage tank is obtained by calculation.

11. The method for testing the ultimate thickness of the bottom ring wall plate of a storage tank according to claim 10, characterized in that, The formula for calculating the thickness of the bottom ring wall plate (8) of the storage tank includes: In the formula: t d - Calculated thickness of the wall plates of the bottom ring of the storage tank in the operating conditions of the storage medium; D - Inner diameter of the storage tank; H - Calculate the liquid level height, which is the height from the bottom of the calculated tank wall plate to the top of the tank wall edging angle steel; - The relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water; - Allowable stress of the steel plate at the design temperature; - Noise level of joint, taken as When the yield strength specified in the standard is greater than 390 MPa, the bottom ring tank wall should be... ; or, In the formula, -Required thickness of the tank bottom ring wall plate; D - Inner diameter of the storage tank; H - Calculate the liquid level height; - The relative density of the storage liquid, which is the ratio of the density of the storage liquid to that of water; - Allowable stress of the steel plate under design conditions, MPa; - Corrosion allowance, take 1mm.

12. The method for testing the ultimate thickness of the bottom ring wall plate of a storage tank according to claim 8, characterized in that, The maximum stress value is compared with the yield stress of the steel to determine the thickness of the bottom ring wall plate (8) of the storage tank. When the maximum stress value is less than the yield stress of the corresponding steel, the thickness of the bottom ring wall plate (8) of the storage tank is qualified.

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