Ice blockage method and detection device

Abstract

The invention relates to an ice blockage method and a detection device. The ice blockage method comprises the steps that a target diameter change value delta R0, a first target stress value sigma 1 and a second target stress value sigma 2 are obtained, refrigeration equipment is arranged at a preset position of a pipeline to be subjected to ice blockage, then a detection device is arranged on the pipeline, the detection device is located on one side of the refrigeration equipment, the pipeline is cooled through the refrigeration equipment, and the pipeline is subjected to ice blockage. The actual diameter change value delta R and the actual stress value sigma of the pipeline are obtained in real time through a detection device, when it is judged that the actual diameter change value delta R and the target diameter change value delta R0 meet the condition that delta R is smaller than or equal to delta R0, the relation between the actual stress value sigma and the first target stress value sigma 1 and the relation between the actual stress value sigma and the second target stress value sigma 2 are continuously judged, if yes, sigma 1 is larger than or equal to sigma 1 and smaller than or equal to sigma 2; if yes, the power of the refrigeration equipment is kept unchanged. The reliability of ice blockage maintenance of the pipeline is improved.

Description

Technical Field

[0001] This application relates to the field of pipeline ice blockage repair technology, and in particular to an ice blockage method and detection device. Background Technology

[0002] Pipeline ice blockage repair is a special process that uses a low-temperature medium to form a solid "ice plug" inside the pipeline to temporarily seal it, thereby enabling localized repair, modification, or replacement of the pipeline. Typically, this is achieved by cooling a section of the pipeline to form an "ice plug." However, as the pipeline cools, it undergoes corresponding deformation. Excessive cooling can easily lead to pipeline cracking, while insufficient cooling can cause the "ice plug" to fail to form, affecting subsequent repair, modification, or replacement procedures.

[0003] However, the reliability and safety of pipeline ice blockage repair in related technologies are low, resulting in low reliability of subsequent pipeline maintenance. Summary of the Invention

[0004] Therefore, it is necessary to provide an ice blockage method and detection device to address the problem that the reliability and safety of pipeline ice blockage repair in related technologies are low, which leads to the low reliability of subsequent pipeline maintenance.

[0005] According to one aspect of this application, an ice-blocking method is provided, the ice-blocking method comprising:

[0006] Obtain the target radial strain value ΔR0, the first target stress value σ1, and the second target stress value σ2;

[0007] The refrigeration equipment is placed at a predetermined position on the pipe to be blocked by ice, and the detection device is placed on the pipe, with the detection device located on one side of the refrigeration equipment.

[0008] The cooling equipment cools the pipe, and the detection device obtains the actual diameter change ΔR and actual stress value σ of the pipe in real time.

[0009] If the actual radial strain value ΔR and the target radial strain value ΔR0 satisfy: ΔR≤ΔR0, then continue to determine the relationship between the actual stress value σ and the first target stress value σ1 and the second target stress value σ2.

[0010] If the actual stress value σ and the first target stress value σ1 satisfy: σ≤σ1, then increase the power of the refrigeration equipment;

[0011] If the actual stress value σ satisfies the following condition: σ1≤σ≤σ2, then the power of the refrigeration equipment remains unchanged;

[0012] If the stress value σ and the second target stress value σ2 satisfy the condition that σ2≤σ, then the refrigeration equipment is controlled to stop working.

[0013] In one embodiment, the ice-blocking method further includes:

[0014] After obtaining the second target stress value σ2, the intermediate target stress value σ3 is obtained. The intermediate target stress value σ3 satisfies: σ3=n*σ2; where n is the safety margin, 0.9<n≤1, and σ1≤σ3;

[0015] After determining that the actual stress value σ satisfies the condition that σ1≤σ≤σ2 with respect to the first target stress value σ1 and the second target stress value σ2, the actual stress value σ is further determined to satisfy the condition that σ3≤σ with respect to the intermediate target stress value σ3. Then, the power of the refrigeration equipment is reduced and the detection device issues an alarm.

[0016] In one embodiment, the detection device includes a connecting rope, a detection component, and a standard plate. The detection component is disposed on the connecting rope. When part of the detection device is disposed on a pipe, the connecting rope is looped on the pipe, and the standard plate is disposed on the side of the detection component away from the pipe along the direction of gravity. The detection component is used to detect the distance between itself and the pipe, and to detect the distance between itself and the standard plate.

[0017] The step of obtaining the actual diameter variation ΔR of the pipe includes:

[0018] Before cooling the pipe, the distance S1 between the detection component and the pipe is obtained through the detection component, and the distance L1 between the detection component and the standard plate is obtained through the detection component;

[0019] After the pipe is cooled down, the distance S2 between the detection component and the pipe is obtained through the detection component, and the distance L2 between the detection component and the standard plate is obtained through the detection component.

[0020] Based on distances S1, S2, L1, and L2, the intermediate diameter variation Δx is obtained, where Δx = S2 - S1 + L2 - L1.

[0021] In one embodiment, the pipe is inclined to the direction of gravity;

[0022] The step of obtaining the actual diameter variation ΔR of the pipe further includes:

[0023] The actual diameter variation ΔR is obtained from the intermediate diameter variation Δx, wherein the actual diameter variation ΔR and the intermediate diameter variation Δx satisfy: Δx=ΔR*cosθ, where θ is the angle between the extension direction of the pipe and the horizontal direction.

[0024] In one embodiment, the step of obtaining the actual stress value σ of the pipe includes:

[0025] The circumferential strain value ε of the pipe is obtained based on the actual diameter change value ΔR; where ε = ΔC / C, ΔC is the circumferential shrinkage value of the pipe, and ΔC = 2 * ΔR * π, C is the original circumference of the pipe, C = π * D, and D is the original outer diameter of the pipe.

[0026] The actual stress value σ is obtained based on the circumferential strain value ε; where σ = ε * E, and E is the elastic modulus of the material used in the pipeline.

[0027] In one embodiment, the step of obtaining the first target stress value σ1 includes:

[0028] Obtain multiple sample tubes;

[0029] The cooling equipment is used to cool down the multiple sample pipes respectively, and the detection device is used to obtain the sample stress value σ4 of the multiple sample pipes respectively.

[0030] The first target stress value σ1 is obtained by averaging the multiple sample stress values ​​σ4.

[0031] In one embodiment, the step of obtaining the sample stress value σ4 of the sample pipeline includes:

[0032] After the sample pipe is cooled by the cooling device until the outer surface of the sample pipe reaches a preset temperature T0, the sample diameter change ΔR1 of the sample pipe is obtained by the detection device.

[0033] The sample stress value σ4 of the sample pipe is obtained based on the sample diameter variation ΔR1, where σ4 = ε0 * E0, E0 is the elastic modulus of the material used in the sample pipe, and ε0 is the circumferential strain value of the sample pipe.

[0034] In one embodiment, the step of obtaining the second target stress value σ2 includes:

[0035] The temperature T of the outer surface of the pipe is obtained when the actual diameter change value ΔR and the target diameter change value ΔR0 satisfy: ΔR≤ΔR0.

[0036] Obtain the allowable stress σ0 of the material used in the pipeline at temperature T;

[0037] The second target stress value σ2 is obtained based on the allowable stress σ0 of the material used in the pipeline at temperature T, where σ2 = ŋ * σ0, and ŋ is the allowable stress correction coefficient.

[0038] According to another aspect of this application, a detection device is provided for implementing the ice blockage method in any of the above embodiments. The detection device includes a connecting rope, a detection component, and a standard plate. The detection component is disposed on the connecting rope, which is used to be sleeved on the pipe. The standard plate is disposed on the side of the detection component away from the pipe along the direction of gravity. The detection component is used to detect the distance between itself and the pipe, and to detect the distance between itself and the standard plate.

[0039] In one embodiment, the detection device further includes a temperature detector for detecting the temperature of the outer surface of the pipe; and / or

[0040] The detection device also includes a control unit and an alarm. The control unit is electrically connected to the alarm and can control the alarm to sound an alarm.

[0041] The aforementioned ice-blocking method first determines whether the actual diameter change of the pipe after cooling is less than the target diameter change. This is because cooling causes pipe contraction, reducing its radial dimension. If the actual diameter change decreases to the target value, it can be preliminarily determined that the liquid inside the pipe is essentially frozen. Secondly, the pipe stress is checked, ensuring the actual stress value falls between the first and second target stress values. If the actual stress value is not less than the first target stress value, it further confirms that the pipe is frozen. The actual stress value not exceeding the second target stress value ensures that the pipe's contraction stress remains within a safe range, preventing excessive contraction that could exceed the pipe's stress tolerance and cause damage. Therefore, the ice-blocking method of this application first preliminarily determines that the liquid inside the pipe is essentially frozen, and then checks whether the stress inside the pipe is within the pipe's stress tolerance range. This facilitates control over the ice-blocking process during cooling, thereby improving the reliability of pipe ice-blocking repairs and pipe safety, and enhancing the reliability of subsequent pipe maintenance. Attached Figure Description

[0042] Figure 1 This is a flowchart illustrating the steps of an ice-blocking method in one embodiment of this application.

[0043] Figure 2 This is a schematic diagram of the detection device installed on the pipeline in one embodiment of this application.

[0044] Figure 3 This is a geometric schematic diagram of pipe cooling and contraction in one embodiment of this application.

[0045] Figure 4 This is a flowchart illustrating the steps for obtaining the actual diameter variation of a pipe in one embodiment of this application.

[0046] Figure 5 This is a flowchart illustrating the steps for obtaining the actual stress value in one embodiment of this application.

[0047] Figure 6 This is a flowchart illustrating the steps for obtaining a first target stress value in one embodiment of this application.

[0048] Figure 7 This is a flowchart illustrating the steps for obtaining a second target stress value in one embodiment of this application.

[0049] Explanation of icon numbers:

[0050] 10. Detection device;

[0051] 1. Connecting rope; 2. Detection assembly; 3. Standard plate; 4. Pipeline. Detailed Implementation

[0052] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0053] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and 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, and therefore should not be construed as a limitation of this application.

[0054] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0055] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0056] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0057] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0058] Pipeline ice blockage repair technology is mainly applied to pipeline systems where shutdown is not possible or the medium is difficult to drain, especially in the nuclear power field. In nuclear power, pipeline repairs involving reactor shutdown are extremely expensive. Using pipeline ice blockage repair technology can avoid reactor shutdowns and reduce costs. However, nuclear power systems have extremely high requirements for safety, reliability, and sealing, and the medium is often radioactive; therefore, the application of ice blockage technology requires overcoming multiple limitations.

[0059] However, the reliability of pipeline ice blockage repair technology in related technologies is low, making it difficult to meet the requirements for pipeline ice blockage in the nuclear power field.

[0060] Based on this, this application provides an ice blockage method and detection device, which is mainly used for the acceptance and judgment of ice blockage effect during pipeline ice blockage repair, so as to improve the reliability of ice blockage and the safety of pipeline.

[0061] See Figure 1 As shown, Figure 1 This is a flowchart illustrating the steps of an ice-blocking method according to one embodiment of this application. The ice-blocking method provided by this application includes:

[0062] Step S1: Obtain the target radial strain value ΔR0, the first target stress value σ1, and the second target stress value σ2. This provides clear quantitative standards for subsequent ice-blocking operations and effect assessment, and helps to accurately control the ice-blocking process.

[0063] Step S2: Place the refrigeration equipment at a preset position on the pipe 4 to be blocked by ice, and then place the detection device 10 on the pipe 4, with the detection device 10 located to one side of the refrigeration equipment. In this way, by cooling the preset position of the pipe 4 with the refrigeration equipment, the liquid in the pipe 4 at the preset position freezes, forming an ice plug that blocks the liquid upstream of the pipe 4, thereby facilitating the venting of liquid downstream of the pipe 4 for maintenance or other operations downstream of the pipe 4.

[0064] The detection device 10 is installed on the pipe 4 and located on one side of the refrigeration equipment to facilitate the detection of the part of the pipe 4 where ice blockage has formed, to ensure that the ice blockage is complete and to prevent leakage when the downstream of the pipe 4 is repaired. At the same time, it avoids the ice blockage from freezing too much, which would cause the pipe 4 to shrink too much and thus break the pipe 4.

[0065] Step S3: Cool the pipe 4 using refrigeration equipment, and obtain the actual radial change ΔR and actual stress value σ of the pipe 4 in real time using the detection device 10. This allows for real-time monitoring of the radial change and stress of the pipe 4 during cooling, enabling timely understanding of the dynamic situation of the ice blockage process and providing data support for subsequent judgment and adjustment. The radial change reflects the freezing completion status of the ice blockage from the perspective of pipe 4's contraction, while the actual stress value σ indicates whether pipe 4 has undergone excessive contraction.

[0066] Step S4: Determine if the actual radial deformation value ΔR and the target radial deformation value ΔR0 satisfy: ΔR≤ΔR0, then continue to determine the relationship between the actual stress value σ and the first target stress value σ1 and the second target stress value σ2.

[0067] By using multi-level judgment logic, the ice blockage effect can be evaluated more meticulously, avoiding misjudgments that may be caused by a single judgment standard, and improving the accuracy and reliability of ice blockage effect acceptance.

[0068] If the actual diameter change ΔR is not greater than the target diameter change ΔR0, it indicates that pipe 4 is basically frozen. This can be understood as pipe 4 cooling and contracting, reducing its radial dimension. Furthermore, if the actual diameter change ΔR of pipe 4 decreases to a certain extent, reaching the target diameter change ΔR0, it can be preliminarily determined that the liquid at that location within pipe 4 is basically frozen.

[0069] In this embodiment, ΔR should be greater than 0. If it is not greater than zero, it means that pipe 4 has not cooled down properly, which may be due to the refrigeration equipment not working properly. It is necessary to check whether the refrigeration equipment is working properly.

[0070] Step S5: If the actual stress value σ and the first target stress value σ1 satisfy: σ≤σ1, it means that the liquid in the pipe 4 has not yet frozen completely, and the power of the refrigeration equipment needs to be increased.

[0071] Thus, by adjusting the power of the refrigeration equipment in a timely manner based on the comparison between the actual stress value σ and the target stress value, the progress of the ice blockage process can be effectively promoted, ensuring that the pipe 4 achieves the expected ice blockage effect and realizing dynamic optimization control of the ice blockage process.

[0072] Step S6: If the actual stress value σ satisfies the following condition: σ1 ≤ σ ≤ σ2, it indicates that the liquid at that point in pipe 4 has frozen completely, and the stress in pipe 4 is within a suitable range. In this case, the power of the refrigeration equipment can be kept constant. Thus, maintaining a stable power for the refrigeration equipment when the actual stress value σ is within a reasonable range helps maintain the stability and continuity of the ice-blocking effect, avoiding unnecessary power fluctuations that could affect the quality of the ice blockage.

[0073] Step S7: If the actual stress value σ and the second target stress value σ2 satisfy the condition that σ2 ≤ σ, then control the refrigeration equipment to stop working. This effectively prevents problems such as excessive stress on pipe 4 caused by over-cooling, avoiding damage to pipe 4 due to excessive stress. Furthermore, while protecting the structural integrity of pipe 4, it effectively avoids energy waste.

[0074] The ice-blocking method of this application first determines whether the actual diameter change ΔR of the pipe 4 after cooling is less than the target diameter change ΔR0. It can be understood that as the pipe 4 cools and contracts, its radial dimension decreases. If the actual diameter change ΔR of the pipe 4 decreases to a certain extent to the target diameter change ΔR0, it can be preliminarily determined that the liquid inside the pipe 4 has essentially frozen. Secondly, the stress in the pipe 4 is measured, ensuring that the actual stress value σ is between the first target stress value σ1 and the second target stress value σ2. If the actual stress value σ is not less than the first target stress value σ1, it further indicates that the freezing of the pipe 4 is complete. The actual stress value σ not exceeding the second target stress value σ2 ensures that the contraction stress of the pipe 4 is within a safe range, preventing excessive contraction that exceeds the stress range the pipe 4 can withstand, thus avoiding damage. As can be seen, the ice-blocking method of this application first preliminarily determines that the liquid inside pipe 4 has basically frozen, and then checks whether the stress inside pipe 4 is within the stress range that pipe 4 can withstand. In this way, it is beneficial to control the ice-blocking situation of pipe 4 during the cooling process, thereby improving the reliability of ice-blocking repair of pipe 4 and the safety of pipe 4, and improving the reliability of subsequent maintenance of pipe 4.

[0075] In some embodiments, continue reading Figure 1 Ice-blocking methods also include:

[0076] Step S11: After obtaining the second target stress value σ2, obtain the intermediate target stress value σ3, which satisfies: σ3 = n * σ2. Where n is the safety margin, 0.9 < n ≤ 1, and σ1 ≤ σ3. Introducing the intermediate target stress value σ3 further refines the evaluation criteria for ice blockage effect, providing a more accurate reference for subsequent stress monitoring and control, enhancing the safety and reliability of the ice blockage process, and reducing potential risks.

[0077] The intermediate target stress value is a defined target value located between the first target stress value σ1 and the second target stress value σ2, and relatively close to the second target stress value σ2. Its main significance is to ensure that the intermediate target stress value σ3 is close to the second target stress value σ2. That is, the intermediate target stress value σ3 is not less than at least 0.9 times the second target stress value σ2. Therefore, if the actual stress value σ reaches the intermediate target stress value σ3, it means that the actual stress value σ is very close to the second target stress value σ2, but has not yet reached it. At this point, timely adjustments can be made to prevent the actual stress value σ from reaching the second target stress value σ2, thus reducing the risk of pipeline 4 rupture due to the actual stress value σ reaching the second target stress value σ2.

[0078] Step S8: After determining that the actual stress value σ satisfies the first target stress value σ1 and the second target stress value σ2 (σ1≤σ≤σ2), further determine that the actual stress value σ satisfies the intermediate target stress value σ3 (σ3≤σ). Then, control the power of the refrigeration equipment to decrease, and the detection device 10 will issue an alarm. σ3≤σ indicates that the actual stress value σ is very close to the second target value, but the pipe 4 has not yet ruptured, and there is still room for adjustment. In this way, the refrigeration power can be adjusted and an alarm can be issued in time when the target stress is approaching its upper limit, reminding the operator to pay attention to the ice blockage status. This avoids the actual stress value σ of the pipe 4 exceeding the second target stress value σ2, which could lead to the pipe 4 rupturing before the problem is discovered. This helps to further ensure the safety and stability of the ice blockage process and effectively prevents accidents such as pipe 4 damage caused by excessive stress.

[0079] In some embodiments, see Figure 1 Combined with reference Figure 2 and Figure 3 As shown, Figure 2 This is a schematic diagram of the structure of the detection device 10 disposed on the pipeline 4 in one embodiment of this application. Figure 3 This is a geometrical schematic diagram of the cooling and shrinking of pipe 4 in one embodiment of this application.

[0080] The detection device 10 includes a connecting rope 1, a detection component 2, and a standard plate 3. The detection component 2 is mounted on the connecting rope 1. When part of the detection device 10 is mounted on the pipe 4, the connecting rope 1 is looped around the pipe 4, and the standard plate 3 is located on the side of the detection component 2 facing away from the pipe 4 along the direction of gravity. The detection component 2 is used to detect the distance between itself and the pipe 4, and also to detect the distance between itself and the standard plate 3. This allows for accurate measurement of the radial change of the pipe 4 during the ice blockage process, and the operation is simple, requiring only the detection of the distance between itself and the pipe 4 and the distance between itself and the standard plate 3.

[0081] The steps to obtain the actual diameter variation ΔR of pipe 4 include:

[0082] Step S31: Before cooling the pipe 4, obtain the distance S1 between the detection component 2 and the pipe 4, and obtain the distance L1 between the detection component 2 and the standard plate 3. Obtaining the initial distance data in advance can provide a reference value for calculating the diameter change of the pipe 4 during the subsequent ice blockage process.

[0083] Step S32: After the pipe 4 cools down, the distance S2 between the detection component 2 and the pipe 4 is obtained through the detection component 2, and the distance L2 between the detection component 2 and the standard plate 3 is also obtained through the detection component 2. In this way, measuring the distance data after cooling down again can intuitively reflect the radial change of the pipe 4 during the ice blockage process.

[0084] Step S33: Based on distances S1, S2, L1, and L2, obtain the intermediate radius variation Δx. (See also...) Figure 3 Δx = S2-S1+L2-L1 represents the amount of cooling and shrinkage of pipe 4 in the direction of gravity. If the extension direction of pipe 4 is horizontal, then the intermediate diameter change Δx represents the amount of cooling and shrinkage of pipe 4 in the radial direction.

[0085] Furthermore, it can be understood that the shrinkage of pipe 4 changes along its radial direction. This application uses the detection device 10 to focus the radial change on the change in a single direction of gravity, which helps to simplify the calculation steps and reduce the complexity of the detection.

[0086] In some embodiments, such as Figure 2 The extension direction of pipe 4 is inclined to the direction of gravity.

[0087] See also Figure 4 As shown, Figure 4 This is a flowchart illustrating the steps for obtaining the actual diameter variation ΔR of pipe 4 in one embodiment of this application. The steps for obtaining the actual diameter variation ΔR of pipe 4 further include:

[0088] Step S34: Obtain the actual diameter variation ΔR based on the intermediate diameter variation Δx, where the actual diameter variation ΔR and the intermediate diameter variation Δx satisfy: Δx = ΔR * cosθ, where θ is the angle between the extension direction of pipe 4 and the horizontal direction. This embodiment considers the actual installation angle of pipe 4 and corrects the intermediate diameter variation by introducing an angle factor, thus enabling a more accurate calculation of the actual radial shrinkage change of pipe 4.

[0089] In some embodiments, see Figure 5 As shown, Figure 5 This is a flowchart illustrating the steps for obtaining the actual stress value σ in one embodiment of this application.

[0090] The steps to obtain the actual stress value σ of pipe 4 include:

[0091] Step S35: Obtain the circumferential strain value ε of pipe 4 based on the actual diameter shrinkage value ΔR. Where ε = ΔC / C, ΔC is the circumferential shrinkage value of pipe 4, and ΔC = 2 * ΔR * π, C is the original circumference of pipe 4, C = π * D, and D is the original outer diameter of pipe 4. The original outer diameter parameter of pipe 4 can be obtained from the pipe 4 instruction manual corresponding to its manufacturing process, and will not be repeated here. Thus, obtaining the circumferential strain value ε first facilitates the calculation of the actual stress value σ in the next step.

[0092] In some embodiments, the circumferential shrinkage value ΔC of pipe 4 and the original circumference C of pipe 4 also satisfy the relationship: ΔC=α*C*ΔT, where ΔT is the temperature difference, which can be taken as the surface temperature T1 of pipe 4 before ice blockage and cooling, and the temperature difference between the actual diameter change value ΔR and the target diameter change value ΔR0 when ΔR≤ΔR0, i.e., ΔT= T1-T2. α is the expansion coefficient of pipe 4 when the surface temperature of pipe 4 is T2. The specific use of α will be recorded in the pipe 4 instruction manual during pipe 4 manufacturing, and can be selected according to the temperature, material, and size of pipe 4, which will not be elaborated further. Thus, in this embodiment, the circumferential shrinkage can be obtained according to ΔC=α*C*ΔT.

[0093] Step S36: Obtain the actual stress value σ based on the circumferential strain value ε. σ = ε * E. This method of obtaining the actual stress value σ allows for a direct assessment of whether the ice blockage has achieved the expected effect. It also provides precise numerical data for subsequent judgment and control, facilitating refined control and management of the ice blockage process. Here, E is the elastic modulus of the material used in pipe 4; the corresponding parameter can be obtained for different materials, and will not be elaborated further here.

[0094] In some embodiments, see Figure 6 As shown, Figure 6 This is a flowchart illustrating the steps for obtaining the first target stress value σ1 in one embodiment of this application.

[0095] The steps to obtain the first target stress value σ1 include:

[0096] Step S12: Obtain multiple sample tubes.

[0097] Step S12: Cool the multiple sample pipes using a refrigeration device, and obtain the sample stress values ​​σ4 of the multiple sample pipes using the detection device 10. By using multiple sample pipes in the experiment, the differences between individual sample pipes can be fully considered, ensuring that the obtained target stress values ​​have broader representativeness and accuracy, thus improving the reliability and applicability of the first target stress value σ1.

[0098] Step S14: The first target stress value σ1 is obtained by averaging the stress values ​​σ4 of the multiple samples. Using the averaging method to determine the first target stress value σ1 can effectively reduce the random errors of individual sample data, making the target stress value more stable and representative.

[0099] In this embodiment, the first target stress value σ1 can also be obtained by removing the maximum and minimum values ​​of multiple sample stress values ​​σ4 and then taking the average, so as to avoid the influence of unstable values ​​and further reduce random errors.

[0100] In some embodiments, continue reading Figure 6 As shown, the steps to obtain the sample stress value σ4 of the sample pipe include:

[0101] Step S121: After cooling the sample pipe with a refrigeration device until the outer surface of the sample pipe reaches a preset temperature T0, the sample diameter change value ΔR1 of the sample pipe is obtained by the detection device 10. By setting specific temperature conditions to obtain the sample diameter change value ΔR1, the consistency and repeatability of the experimental conditions can be ensured, and the obtained diameter change value can better reflect the true changes of the pipe 4 under specific ice blockage conditions.

[0102] In this embodiment, for example, when the liquid inside pipe 4 is water and the pipe 4 is made of carbon steel, T0 can be approximately -30°F (-34.40°C). For example, when the liquid inside pipe 4 is water and the pipe 4 is made of stainless steel, T0 can be approximately -80°F (-62.20°C). The specific preset temperature T0 can be selected mainly based on the liquid inside pipe 4 and the material of pipe 4. Furthermore, when manufacturing pipe 4 in a nuclear power system, the corresponding pipe 4 parameters are provided in the instruction manual, including the preset temperature T0 for the approximate formation of an ice plug on pipe 4, which will not be elaborated upon here.

[0103] Step S122: Obtain the sample stress value σ4 of the sample channel based on the sample diameter variation ΔR1, where σ4 = ε0 * E0, E0 is the elastic modulus of the material used in the sample channel, and ε0 is the circumferential strain value of the sample channel. This facilitates the determination of the first target stress value σ1 based on the sample stress value σ4.

[0104] It is understood that the first target stress value σ1 of this application is obtained through the sample stress value σ4. Both the sample stress value σ4 and the actual stress value σ are calculated after being measured by the detection device 10 of this application. Thus, the detection tools, detection process and calculation method of the two are the same, which reduces the error in obtaining the sample stress value σ4. This is conducive to further improving the reference value of the sample stress value σ4, and thus improving the comparability between the actual stress value σ and the first target stress value σ1. It is also conducive to accurately reflecting the actual stress condition of the pipeline 4 through the first target stress value σ1.

[0105] In some embodiments, the first target stress value σ1 can also be obtained through experience. When the pipe 4 is manufactured, the instruction manual of the pipe 4 records the operating pressure of the pipe 4. Usually, when the pipe 4 is sealed with an ice plug, the actual stress value σ of the pipe 4 is greater than or equal to twice the operating pressure of the pipe 4 recorded in the instruction manual of the pipe 4. That is to say, the first target stress value σ1 can be taken as about twice the operating pressure of the pipe 4, which will not be elaborated here.

[0106] In some embodiments, see Figure 7 As shown, Figure 7 This is a flowchart illustrating the steps for obtaining the second target stress value σ2 in one embodiment of this application. The steps for obtaining the second target stress value σ2 include:

[0107] Step S15: Obtain the temperature T of the outer surface of pipe 4 when the actual diameter change ΔR and the target diameter change ΔR0 satisfy: ΔR≤ΔR0. At this point, first determine that pipe 4 is basically blocked by ice plugs, and then obtain the temperature of the outer surface of pipe 4 for subsequent judgments.

[0108] Step S16: Obtain the allowable stress σ0 of the material used in pipe 4 at temperature T. The allowable stress σ0 is the maximum allowable stress of the material used in pipe 4 at the corresponding temperature T, which can be obtained from known information based on different materials, and will not be elaborated further.

[0109] Step S17: Obtain the second target stress value σ2 based on the allowable stress σ0 of the material used in pipe 4 at temperature T, where σ2 = ŋ * σ0, and ŋ is the allowable stress correction factor. This correction factor is affected by various factors, such as material, manufacturing process, and size, and varies accordingly. It should be noted that the correction factor for the allowable stress of pipe 4 will be specified in the pipe 4 instruction manual during pipe 4 manufacturing, and can be entered into the control component database for selection based on the actual situation. For example, ŋ = 1 for seamless steel pipes and ŋ = 0.9 for spiral welded steel pipes, as specified in the product technical conditions of the corresponding pipe 4; further details are omitted here.

[0110] This application also provides a detection device 10, see reference. Figure 2 and Figure 3 As shown, the detection device 10, used to implement the ice blockage method in any of the above embodiments, includes a connecting rope 1, a detection component 2, and a standard plate 3. The detection component 2 is disposed on the connecting rope 1, which is used to be sleeved on the pipe 4. The standard plate 3 is disposed on the side of the detection component 2 away from the pipe 4 along the direction of gravity. The detection component 2 is used to detect the distance between itself and the pipe 4, and to detect the distance between itself and the standard plate 3.

[0111] In some embodiments, the connecting rope 1 may be made of heat-insulating material, which is not affected by temperature, in order to improve the accuracy of the position change of the detection component 2 and improve the detection accuracy.

[0112] In some embodiments, the detection device 10 further includes a temperature detector for detecting the temperature of the outer surface of the pipe 4, for obtaining the outer surface temperature T of the pipe 4, and also for obtaining the outer surface temperature T0 of the sample pipe 4. The temperature detector can be a handheld or a hands-free detector, without much limitation.

[0113] In some embodiments, the detection device 10 further includes a control unit and an alarm. The control unit is electrically connected to the alarm and is capable of controlling the alarm to sound an alarm. Thus, when the control unit determines that the actual stress value σ exceeds the intermediate target stress value σ3, it controls the alarm to sound an alarm to alert the operator.

[0114] The detection device 10 also includes a display element and a sound element, which are electrically connected to a control unit. The control unit can control the display element to emit light and the sound element to emit sound prompts, so as to control the alarm and the light element to emit sound and light prompts.

[0115] For example, after the controller determines that the actual diameter variation ΔR and the target diameter variation ΔR0 satisfy ΔR≤ΔR0, and then determines that the actual stress value σ and the first target stress value σ1 satisfy σ≤σ1, the controller will control the display element to display the words "Ice plug qualified" and control the sound element to emit a "Ice plug qualified" prompt.

[0116] If the actual stress value σ is determined to satisfy the condition that σ1≤σ≤σ2 with respect to the first target stress value σ1 and the second target stress value σ2, then the control component will display the message "Approaching the allowable strength of the pipeline, please operate with caution" and control the sound component to emit the message "Approaching the allowable strength of the pipeline, please operate with caution".

[0117] If the actual stress value σ and the second target stress value σ2 satisfy the condition that σ2≤σ, the control component will display the message "Exceeds the allowable strength of the pipeline, please initiate the maintenance evaluation process" and control the sound component to issue the message "Exceeds the allowable strength of the pipeline, please initiate the maintenance evaluation process".

[0118] In some embodiments, the controller is electrically connected to the detection component 2 to obtain the values ​​detected by the detection component 2, and calculates the actual diameter change value ΔR and the actual stress value σ based on the values ​​detected by the detection component 2. The conditional judgment between the actual diameter change value ΔR and the target diameter change value ΔR0, as well as the conditional judgment between the target diameter change value ΔR0, the first target stress value σ1, the second target stress value σ2, and the intermediate target stress value σ3, are also compared and judged by the controller.

[0119] Among them, parameters such as the original outer diameter D of pipe 4, the angle θ between the extension direction of pipe 4 and the horizontal direction, the first target stress value σ1 obtained in advance, the corresponding elastic modulus of pipe 4, the allowable stress σ0 of the corresponding material, and the allowable stress correction coefficient ŋ are all input into the controller's database in advance for subsequent use, and will not be elaborated here.

[0120] In some embodiments, the control unit is also electrically connected to the refrigeration equipment to control the power of the refrigeration equipment to make corresponding adjustments after the control unit determines that the actual radial deformation value ΔR and the actual stress value σ meet the corresponding conditions. This will not be elaborated further here.

[0121] The ice blockage method and detection device 10 of this application are specifically designed for the maintenance of pipeline systems in nuclear power plants where shutdown is not possible. By quantifying the target diameter change value ΔR0, the first target stress value σ1, and the second target stress value σ2, and using the detection device 10 to monitor the actual diameter change value ΔR and the actual stress value σ in real time during the cooling process of the pipeline 4, multi-level judgment and dynamic control are implemented. When ΔR≤ΔR0 initially confirms ice blockage, the cooling power is further intelligently adjusted based on the σ value. Simultaneously, an intermediate target stress value σ3 can be optionally introduced to trigger power reduction and alarms to reserve a safety margin. The corresponding detection device 10, by measuring the cold contraction displacement of the pipeline 4 and deriving the actual stress, combined with the target value based on sample experiments or pipeline 4 parameter settings, achieves accurate acceptance judgment of the ice blockage effect, significantly improving the reliability of ice blockage. While ensuring the structural safety of the pipeline 4 and preventing overcooling rupture, it also meets high sealing requirements, effectively solving the problem that traditional technologies struggle to meet nuclear power safety standards.

[0122] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0123] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for ice blocking, characterized in that, The ice-blocking method includes: Obtain the target radial strain value ΔR0, the first target stress value σ1, and the second target stress value σ2; The refrigeration equipment is placed at a predetermined position on the pipe to be blocked by ice, and the detection device is placed on the pipe, with the detection device located on one side of the refrigeration equipment. The cooling equipment cools the pipe, and the detection device obtains the actual diameter change ΔR and actual stress value σ of the pipe in real time. If the actual radial strain value ΔR and the target radial strain value ΔR0 satisfy: ΔR≤ΔR0, then continue to determine the relationship between the actual stress value σ and the first target stress value σ1 and the second target stress value σ2. If the actual stress value σ and the first target stress value σ1 satisfy: σ≤σ1, then increase the power of the refrigeration equipment; If the actual stress value σ satisfies the following condition: σ1≤σ≤σ2, then the power of the refrigeration equipment remains unchanged; If the actual stress value σ and the second target stress value σ2 satisfy the condition that σ2≤σ, then the refrigeration equipment is controlled to stop working.

2. The ice-blocking method according to claim 1, characterized in that, The ice-blocking method also includes: After obtaining the second target stress value σ2, the intermediate target stress value σ3 is obtained. The intermediate target stress value σ3 satisfies: σ3=n*σ2; where n is the safety margin, 0.9<n≤1, and σ1≤σ3; After determining that the actual stress value σ satisfies the condition that σ1≤σ≤σ2 with respect to the first target stress value σ1 and the second target stress value σ2, the actual stress value σ is further determined to satisfy the condition that σ3≤σ with respect to the intermediate target stress value σ3. Then, the power of the refrigeration equipment is reduced and the detection device issues an alarm.

3. The ice-blocking method according to claim 1, characterized in that, The detection device includes a connecting rope, a detection component, and a standard plate. The detection component is mounted on the connecting rope. When part of the detection device is mounted on a pipe, the connecting rope is looped around the pipe. The standard plate is mounted on the side of the detection component that is away from the pipe along the direction of gravity. The detection component is used to detect the distance between itself and the pipe, and also to detect the distance between itself and the standard plate. The step of obtaining the actual diameter variation ΔR of the pipe includes: Before cooling the pipe, the distance S1 between the detection component and the pipe is obtained through the detection component, and the distance L1 between the detection component and the standard plate is obtained through the detection component; After the pipe is cooled down, the distance S2 between the detection component and the pipe is obtained through the detection component, and the distance L2 between the detection component and the standard plate is obtained through the detection component. Based on distances S1, S2, L1, and L2, the intermediate diameter variation Δx is obtained, where Δx = S2 - S1 + L2 - L1.

4. The ice-blocking method according to claim 3, characterized in that, The extension direction of the pipeline is inclined to the direction of gravity; The step of obtaining the actual diameter variation ΔR of the pipe further includes: The actual diameter variation ΔR is obtained from the intermediate diameter variation Δx, wherein the actual diameter variation ΔR and the intermediate diameter variation Δx satisfy: Δx=ΔR*cosθ, where θ is the angle between the extension direction of the pipe and the horizontal direction.

5. The ice-blocking method according to claim 1, characterized in that, The step of obtaining the actual stress value σ of the pipeline includes: The circumferential strain value ε of the pipe is obtained based on the actual diameter change value ΔR; where ε = ΔC / C, ΔC is the circumferential shrinkage value of the pipe, and ΔC = 2 * ΔR * π, C is the original circumference of the pipe, C = π * D, and D is the original outer diameter of the pipe. The actual stress value σ is obtained based on the circumferential strain value ε; where σ = ε * E, and E is the elastic modulus of the material used in the pipeline.

6. The ice-blocking method according to claim 1, characterized in that, The step of obtaining the first target stress value σ1 includes: Obtain multiple sample tubes; The cooling equipment is used to cool down the multiple sample pipes respectively, and the detection device is used to obtain the sample stress value σ4 of the multiple sample pipes respectively. The first target stress value σ1 is obtained by averaging the multiple sample stress values ​​σ4.

7. The ice-blocking method according to claim 6, characterized in that, The step of obtaining the sample stress value σ4 of the sample pipeline includes: After the sample pipe is cooled by the cooling device until the outer surface of the sample pipe reaches a preset temperature T0, the sample diameter change ΔR1 of the sample pipe is obtained by the detection device. The sample stress value σ4 of the sample pipe is obtained based on the sample diameter variation ΔR1, where σ4 = ε0 * E0, E0 is the elastic modulus of the material used in the sample pipe, and ε0 is the circumferential strain value of the sample pipe.

8. The ice-blocking method according to claim 1, characterized in that, The step of obtaining the second target stress value σ2 includes: The temperature T of the outer surface of the pipe is obtained when the actual diameter change value ΔR and the target diameter change value ΔR0 satisfy: ΔR≤ΔR0. Obtain the allowable stress σ0 of the material used in the pipeline at temperature T; The second target stress value σ2 is obtained based on the allowable stress σ0 of the material used in the pipeline at temperature T, where σ2 = ŋ * σ0, and ŋ is the allowable stress correction coefficient.

9. A detection device, characterized in that, For implementing the ice blockage method as described in any one of claims 1-8, the detection device includes a connecting rope, a detection component, and a standard plate. The detection component is disposed on the connecting rope, which is used to be sleeved on the pipe. The standard plate is disposed on the side of the detection component away from the pipe along the direction of gravity. The detection component is used to detect the distance between itself and the pipe, and to detect the distance between itself and the standard plate.

10. The detection device according to claim 9, characterized in that, The detection device further includes a temperature detector for detecting the temperature of the outer surface of the pipe; and / or The detection device also includes a control unit and an alarm. The control unit is electrically connected to the alarm and can control the alarm to sound an alarm.

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