Radiation-proof lead brick gap sealing test method

Abstract

The application provides a kind of radiation-proof lead brick gap sealing test method, it is related to structural sealing test technical field, comprising: setting independent sealing detection gas chamber to each interlayer gap, obtaining lead brick quality and gas chamber volume, collecting pressure and temperature data and preprocessing;Calculate the instantaneous leakage rate of each gap, construct sliding window and calculate the relative volatility, determine the stable leakage rate after the leakage rate is stable;Calculate the interlayer monotonicity coefficient of adjacent gap, determine whether there is physical anomaly;For lead brick stack without anomaly, calculate the cumulative weight above each gap based on lead brick quality, and then calculate the leakage rate determination threshold, compare the stable leakage rate with the threshold to determine the sealing property.The application realizes independent detection of the sealing property of each gap, identifies physical anomaly through interlayer monotonicity coefficient, and adaptively adjusts the threshold based on the weight of lead brick, improves the accuracy and reliability of test results.

Description

Technical Field

[0001] This invention relates to the field of structural sealing test technology, specifically a method for testing the sealing performance of gaps in radiation-proof lead bricks. Background Technology

[0002] Radiation-shielding lead bricks are widely used in nuclear industry, nuclear medicine, and scientific research shielding areas. They are formed by vertically aligning individual bricks layer by layer to create shielding walls or structures. After stacking, gaps inevitably form between adjacent lead bricks, and these gaps are the main potential pathways for radiation leakage. The sealing performance of these gaps directly determines the reliability of the overall shielding effect—even if the shielding performance of an individual lead brick is fully up to standard, if the gaps are not properly sealed, radiation can still escape along the gap path, leading to shielding failure and posing a serious threat to personnel safety and the environment. Therefore, accurate sealing tests on the gaps between lead bricks are a crucial step in ensuring the safe operation of the shielding structure.

[0003] In the prior art, patent publication number CN202411504132.8 discloses a method for evaluating the sealing performance of gap fit of machine plate fasteners. This technology includes: initial leakage rate detection, air pressure loading test, leakage state detection after helium stamping, data analysis and evaluation, and formation of evaluation method.

[0004] However, the judgment logic of the above-mentioned existing technologies is limited to a simple comparison of leakage rates before and after loading. It does not involve the dynamic stability judgment of leakage rates in the time dimension, nor does it consider the differential impact of the self-weight compression effect at different heights in the stacked structure on the sealing performance of the gaps between each layer. Therefore, for the interlayer gap sealing test of radiation-proof lead brick stacks, a systematic test method that can realize independent detection of each layer gap, dynamic stability judgment, physical anomaly identification, and adaptive threshold judgment is still needed.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a method for testing the sealing performance of gaps in radiation-shielding lead bricks, thereby addressing the problems mentioned in the background section. This invention establishes an independent sealing detection chamber for each layer gap, collects and preprocesses pressure and temperature data in real time, calculates the instantaneous leakage rate, and uses a sliding window and relative volatility to determine if the leakage rate is stable, thus obtaining a stable leakage rate. Furthermore, it identifies physical anomalies through interlayer monotonic coefficients. Finally, it constructs an adaptive leakage rate threshold based on the cumulative weight of the lead bricks, achieving accurate determination of the sealing performance of each layer gap.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A method for testing the sealing performance of gaps in radiation-shielding lead bricks includes the following steps: S1: A sealing test is performed on a pile of lead bricks with multiple interlayer gaps. The pile of lead bricks is formed by stacking multiple lead bricks vertically in a layer-by-layer manner. An independent sealing test chamber is set for each interlayer gap. The mass data of each lead brick and the volume data of each sealing test chamber are obtained. The pressure data and temperature data in each sealing test chamber are collected at fixed time intervals. The collected pressure data and temperature data are preprocessed. S2: Based on the preprocessed pressure and temperature data, calculate the instantaneous leakage rate of each interlayer gap at each sampling time. For each interlayer gap, construct a corresponding leakage rate sliding window and input the instantaneous leakage rate of each interlayer gap into the corresponding leakage rate sliding window. Based on the instantaneous leakage rate within each leakage rate sliding window, calculate the relative fluctuation rate of the leakage rate of each interlayer gap. Based on the relative fluctuation rate of the leakage rate of each interlayer gap, determine whether the leakage rate of each interlayer gap is stable. After determining that it is stable, obtain the stable leakage rate of each interlayer gap. After all interlayer gaps have obtained a stable leakage rate, proceed to step S3. S3: Based on the stable leakage rate of each interlayer gap, calculate the interlayer monotonic coefficient of two adjacent interlayer gaps in order from top to bottom, and determine whether there is a physical anomaly in each interlayer gap based on the interlayer monotonic coefficient. S4: For a pile of lead bricks where there are no physical abnormalities in any of the interlayer gaps, calculate the leakage rate judgment threshold for each interlayer gap based on the quality data of each lead brick, and compare the stable leakage rate of each interlayer gap with the corresponding leakage rate judgment threshold. Determine whether the sealing performance of each interlayer gap is qualified based on the comparison results.

[0008] Furthermore, the method used for preprocessing the collected pressure and temperature data is as follows: The preprocessing includes data cleaning and data smoothing filtering; The data cleaning process includes handling outliers and missing values. Statistical methods are used to identify outliers in the pressure and temperature data of each sealed detection chamber, and these outliers are deleted. Linear interpolation is then used to fill in the missing values ​​in the pressure and temperature data of each sealed detection chamber.

[0009] Furthermore, the data smoothing filtering method is as follows: Using the sampling time corresponding to a fixed time interval as the reference time point, an equally spaced reference time axis is constructed. The cleaned pressure data and temperature data are matched with the reference time axis according to their respective original timestamps. For each sealed detection chamber, a pressure data time series and a temperature data time series for each sealed detection chamber are constructed. For each pressure data time series and temperature data time series, a median filter is performed using a one-sided sliding window of length K. The one-sided sliding window consists of the data at the current sampling time and the data at the previous K-1 sampling times, where K is a preset odd number and K≥3.

[0010] Furthermore, the formula used to calculate the instantaneous leakage rate of the interlayer gap at each sampling time is as follows: in, For the first The interlayer gap is Instantaneous leakage rate at any given moment; For the first The interlayer gap is Stress data at any given moment; For the first The interlayer gap is Stress data at any given moment; For the first Volume data of the sealing test chamber corresponding to each interlayer gap; Standard atmospheric pressure; For the first The sealing detection chamber corresponding to each interlayer gap is Temperature data at any given time; This is the preset reference temperature; The time interval is a preset fixed interval. Furthermore, the method for constructing the leakage rate sliding window is as follows: Starting from the current sampling time, backtrack in the reverse direction of time sequence and extract the instantaneous leakage rates corresponding to the most recent W consecutive sampling times to form a leakage rate sliding window, where W is the total number of instantaneous leakage rates within the leakage rate sliding window, and W≥5; Once W instantaneous leakage rates have been entered into the leakage rate sliding window, when a new instantaneous leakage rate corresponding to a sampling time is entered, the instantaneous leakage rate corresponding to the earliest sampling time in the leakage rate sliding window is removed, so that the leakage rate sliding window always contains the instantaneous leakage rates corresponding to the most recent W sampling times.

[0011] Furthermore, the formula used to calculate the relative fluctuation rate of the leakage rate between each layer is as follows: in, for Time of the first The relative volatility of interlayer gap leakage rate; for Time of the first The standard deviation of all instantaneous leakage rates within the sliding window corresponding to the leakage rate of each interlayer gap; for Time of the first The average of all instantaneous leakage rates within the sliding window corresponding to the leakage rate of each interlayer gap; The value is a preset positive number to prevent the denominator from being zero. Furthermore, the logic for determining whether the leakage rate between each layer is stable is as follows: when < And lasting longer than At that time, the judgment of the first The interlayer leakage rate has stabilized, and the average of all instantaneous leakage rates within the current leakage rate sliding window is used as the first... Stable leakage rate of interlayer gaps ; when ≥ ,or < However, the duration did not exceed At that time, the judgment of the first The leakage rate between layers was not stable; in, The preset time threshold; This is the preset stability threshold.

[0012] Furthermore, the formula used to calculate the interlayer monotonicity coefficient of two adjacent interlayer gaps is as follows: for the first interlayer gap from top to bottom... The interlayer gap is calculated. The interlayer gap and the first Interlayer monotonicity coefficient of each interlayer gap; in, For the first Interlayer monotonicity coefficient of each interlayer gap; For the first Stable leakage rate of interlayer gaps; when At that time, that is, the first interlayer gap from top to bottom, ,in, The preset leakage rate is based on the self-weight of a single brick. Furthermore, the logic for determining whether there are physical anomalies in the gaps between layers is as follows: when When <1, determine the first There are no physical anomalies in the interlayer gaps; when When ≥1, determine the first There are physical anomalies in the interlayer gaps.

[0013] Furthermore, the formula used to calculate the leakage rate threshold for the interlayer gaps is as follows: in, For the first The threshold for determining the leakage rate of interlayer gaps; The preset baseline leakage rate threshold; For the first The cumulative weight above each interlayer gap is calculated using the following formula: ,in, For the top to bottom Quality data of lead bricks; The baseline mass of the lead brick is the preset value; The preset compression sealing coefficient, and >0; The logic for determining whether the sealing performance of the gaps between each layer is qualified based on the comparison results is as follows: when ≤ At that time, the judgment of the first The sealing performance of the interlayer gaps is qualified; when > At that time, the judgment of the first The sealing performance of the interlayer gaps is substandard; When the sealing performance of all interlayer gaps is deemed satisfactory, the overall sealing performance of the lead brick pile is deemed satisfactory.

[0014] Compared with the prior art, the beneficial effects of the present invention are: This invention utilizes a sliding window for leakage rate combined with relative volatility to determine the stable state of leakage rate, filtering out transient interference and ensuring that the obtained stable leakage rate truly reflects the inherent leakage characteristics of the gap, thus improving the reliability of the test results. Based on the interlayer monotonic coefficient, a ratio analysis of the stable leakage rates of adjacent gaps can quickly identify structural defects that cause abnormally high leakage rates due to brick misalignment, tilting, or foreign object insertion, avoiding misjudging physical anomalies as sealing failures and enhancing the fault location capability and accuracy of the test. Simultaneously, the cumulative weight above each gap is calculated based on the mass data of each lead brick, and an adaptive leakage rate judgment threshold that varies with pressure is constructed. This threshold is based on the compression sealing effect of the lead brick's own weight on the gap sealing performance, making the judgment of whether the sealing performance is qualified more closely aligned with actual working conditions. Ultimately, this achieves an accurate and comprehensive assessment of the overall sealing performance of the lead brick stack. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall process for testing the sealing performance of gaps in radiation-proof lead bricks. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0017] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly. Example

[0018] Please see Figure 1 The present invention provides a technical solution: A method for testing the sealing performance of gaps in radiation-shielding lead bricks includes the following steps: S1: When conducting a sealing test on a lead brick stack with multiple interlayer gaps, the stack is formed by stacking multiple lead bricks vertically in a layer-by-layer arrangement. Horizontal interlayer gaps naturally form between each layer of lead bricks, and these gaps are distributed sequentially along the height of the stack. To accurately evaluate the sealing performance of each interlayer gap, an independent sealing detection chamber is set up for each gap. These chambers are isolated from each other and do not communicate with each other, ensuring that leakage in each gap can be captured individually without crosstalk from leaking airflow from adjacent gaps. Based on this, the mass data of each lead brick is acquired, and the volume data corresponding to each sealing detection chamber is measured and recorded. Pressure and temperature data within each sealing detection chamber are collected at fixed time intervals to capture the dynamic changes in pressure and temperature at different times. In this embodiment: for pressure data acquisition, an independent detection hole is opened on the sealing component of each sealing detection chamber, and each chamber is connected to its corresponding miniature pressure sensor through this detection hole.

[0019] In a preferred embodiment, the miniature pressure sensor can be an intelligent sensor with integrated temperature compensation to reduce the cross-influence of ambient temperature changes on pressure measurement accuracy. The signal lines of each sensor are independently led out and connected to a multi-channel data acquisition system. For temperature data acquisition: an independent temperature sensor is inserted into the chamber through a detection hole in the sealing assembly of each sealed detection chamber. In this embodiment, a thermistor temperature sensor is selected. The sensor signal lines are led out through the sealed structure and connected to the data acquisition system. The pressure and temperature sensors in each chamber are independently configured, with separate signal lines that do not interfere with each other. This enables independent acquisition of pressure and temperature data from each independent sealed detection chamber. The pressure and temperature sensors together constitute a complete intelligent sensing system. Each sensor node achieves synchronous sampling through the multi-channel data acquisition system, ensuring strict temporal consistency of pressure and temperature data from each chamber. The acquired pressure and temperature data are preprocessed to eliminate noise, abnormal fluctuations, or environmental interference that may exist in the raw data, thus providing a standardized data foundation for subsequent analysis. The method used for preprocessing the collected pressure and temperature data is as follows: The preprocessing includes data cleaning and data smoothing filtering; The data cleaning includes handling outliers and missing values. Statistical methods are used to identify outliers in the pressure and temperature data of each sealed test chamber. Specifically, for each sealed test chamber, statistical calculations are performed separately on its pressure data sequence and temperature data sequence: for the pressure data sequence in the chamber, the mean and standard deviation of all pressure data points in the sequence are calculated; for the temperature data sequence in the chamber, the mean and standard deviation of all temperature data points in the sequence are calculated. Data points deviating from their corresponding mean by more than ±3 standard deviations in each data sequence are identified as outliers. This effectively eliminates non-realistic physical fluctuations caused by instantaneous sensor disturbances, sudden changes in the external environment, or occasional malfunctions in the data acquisition system. After identifying outliers, they are deleted from the pressure and temperature data in each sealed detection chamber to avoid interfering with subsequent leakage rate calculations. For missing values, linear interpolation is used to fill in the missing values ​​in the pressure and temperature data in each sealed detection chamber. That is, based on the valid data points before and after the missing point, the interpolation value is calculated according to the time interval ratio. This fills the data gaps with reasonable estimates while maintaining the continuity and temporal integrity of the data sequence. This ensures that the pressure and temperature data sequences in each chamber are continuous and equidistant complete sequences, providing standardized and complete data input for subsequent data smoothing filtering and leakage rate calculations.

[0020] The data smoothing and filtering method is as follows: Using the sampling times corresponding to fixed time intervals as reference time points, an equally spaced reference time axis is constructed. The time points on this reference time axis are evenly distributed. The cleaned pressure and temperature data are matched with the reference time axis according to their respective original timestamps. For cases where the original timestamps and reference time points may not completely coincide during the matching process, the data is assigned to the nearest reference time point according to the principle of time proximity, so that all data points fall on equally spaced reference time points, forming a unified time alignment reference. For each sealed detection chamber, a pressure data time series and a temperature data time series for each sealed detection chamber are constructed. The pressure data time series is composed of all matched pressure data in the chamber arranged in chronological order according to the reference time points, and each pressure data corresponds to a unique reference time point; the temperature data time series is similarly constructed. For each pressure data time series and temperature data time series, a median filter is performed using a single-sided sliding window of length K. The single-sided sliding window consists of the data at the current sampling time and the data at the previous K-1 sampling times. During filtering, the window slides from the first valid data point of the time series and gradually moves to the last data point. At each window position, extract all data within the window, sort them in ascending order of numerical value, and take the value in the middle position after sorting (i.e., the median) as the filtered output value at the current sampling time. Here, K is a preset odd number, and K≥3.

[0021] S2: Based on the preprocessed pressure and temperature data, calculate the instantaneous leakage rate of each interlayer gap at each sampling time. This instantaneous leakage rate reflects the leakage amount of the corresponding interlayer gap per unit time at the current sampling time, and is used to describe the real-time leakage behavior of the gap under transient conditions. For each interlayer gap, construct a corresponding leakage rate sliding window and input the instantaneous leakage rate of each interlayer gap into the corresponding leakage rate sliding window. Based on the instantaneous leakage rate within each leakage rate sliding window, calculate the relative volatility of the leakage rate of each interlayer gap. This relative volatility reflects the degree of dispersion of the instantaneous leakage rate within the current leakage rate sliding window relative to its mean, and is used to quantify the severity of the leakage rate fluctuation. Based on the relative volatility of the leakage rate of each interlayer gap, determine whether the leakage rate of each interlayer gap is stable, and obtain the stable leakage rate of each interlayer gap after determining that it is stable. This stable leakage rate reflects the inherent leakage characteristics of the interlayer gap after eliminating transient interference, and is the core basis for subsequent determination. After all interlayer gaps have obtained stable leakage rates, proceed to step S3. The formula used to calculate the instantaneous leakage rate of the interlayer gaps at each sampling time is as follows: in, For the first The interlayer gap is Instantaneous leakage rate at any given moment; For the first The interlayer gap is Stress data at any given moment; For the first The interlayer gap is Stress data at any given moment; For the first Volume data of the sealing test chamber corresponding to each interlayer gap; Standard atmospheric pressure; For the first The sealing detection chamber corresponding to each interlayer gap is Temperature data at any given time; This is the preset reference temperature; A preset fixed time interval; This represents the pressure drop between adjacent sampling times. The larger the pressure drop, the faster the pressure in the gas chamber decreases per unit time, indicating a more severe gas leak, and thus the instantaneous leakage rate. The larger the pressure drop, the worse the sealing performance of the interlayer gap; conversely, the smaller the pressure drop, the lower the leakage rate, and the better the sealing performance. It should be noted that the pressure and temperature data relied upon for the above instantaneous leakage rate calculation are all sourced from the synchronous acquisition and output of sensor nodes within the same intelligent sensing system. This ensures strict alignment of the pressure and temperature variables in the formula on the time reference, avoiding calculation deviations caused by data time misalignment. The method for constructing the leakage rate sliding window is as follows: Starting from the current sampling time, backtracking in the reverse direction of time, the instantaneous leakage rates corresponding to the most recent W consecutive sampling times are extracted to form a leakage rate sliding window, where W is the total number of instantaneous leakage rates in the leakage rate sliding window, and W≥5, to ensure that there are enough data points in the window to reflect the changes in leakage rate in the recent time range. Once W instantaneous leakage rates have been entered into the leakage rate sliding window, each time a new instantaneous leakage rate corresponding to a sampling time is entered, the instantaneous leakage rate corresponding to the earliest sampling time in the leakage rate sliding window is removed. Through the above update method, the leakage rate sliding window can continuously and dynamically update its internal data throughout the entire test process, always ensuring that all the instantaneous leakage rates stored in the window come from the W sampling times closest to the current time.

[0022] The formula used to calculate the relative fluctuation rate of leakage rate between each layer is as follows: in, for Time of the first The relative volatility of interlayer gap leakage rate; for Time of the first The standard deviation of all instantaneous leakage rates within the sliding window corresponding to the leakage rate of each interlayer gap; for Time of the first The average of all instantaneous leakage rates within the sliding window corresponding to the leakage rate of each interlayer gap; The standard deviation is a pre-set positive number to prevent the denominator from being zero. This reflects the degree of dispersion of the instantaneous leakage rate relative to its mean within the leakage rate sliding window. The larger the value, the greater the difference in instantaneous leakage rates within the leakage rate sliding window, and the more drastic the fluctuation in leakage rate. In this case, the relative volatility... The increase in size indicates that the leakage behavior of the interlayer gap has not yet reached a steady state and is still affected by transient disturbances or fluctuations in test conditions; conversely, The smaller, The smaller the value, the more uniform the instantaneous leakage rate within the leakage rate sliding window tends to be, indicating a smooth leakage process and meeting the prerequisites for entering the stability judgment. The judgment logic for determining whether the leakage rate between each layer is stable is as follows: when... < And lasting longer than At that time, the judgment of the first The interlayer leakage rate has stabilized, and the arithmetic mean of all instantaneous leakage rates within the current leakage rate sliding window is used as the first... Stable leakage rate of interlayer gaps This mean represents the overall leakage rate level within the window period, reflecting the inherent leakage characteristics of the gap in a steady state. If one of the following two conditions occurs, the leakage rate of the interlayer gap is determined to be unstable: First, when... ≥ At this time, it indicates that the relative fluctuation range of the leakage rate is still at a high level, which is insufficient to determine stability. Secondly, when < However, the duration did not exceed If the volatility temporarily meets the threshold condition, the duration is insufficient to confirm that the leakage rate has truly entered a long-term stable state, and further observation is still needed. In the above two unstable situations, a stable leakage rate is not output, and the first condition is determined. The leakage rate between layers was not stable; in, The preset time threshold; S3: Based on the stable leakage rate of each interlayer gap, calculate the interlayer monotonic coefficient of adjacent interlayer gaps in order from top to bottom. The interlayer monotonic coefficient reflects the ratio of the stable leakage rate between adjacent upper and lower interlayer gaps, and is used to quantify the trend of leakage rate change along the vertical direction. Based on the interlayer monotonic coefficient, determine whether there is a physical anomaly in each interlayer gap. The formula used to calculate the interlayer monotonicity coefficient of the gap between two adjacent layers is as follows: For the first from top to bottom The gaps between layers are calculated sequentially, following the natural order of the lead brick stacking, starting from the topmost gap and working downwards layer by layer. The interlayer gap and the adjacent first layer above it Interlayer monotonicity coefficient of each interlayer gap; in, For the first Interlayer monotonicity coefficient of each interlayer gap; For the first The stable leakage rate of the interlayer gap; when At that time, that is, the first interlayer gap from top to bottom, ,in, The preset single-brick self-weight reference leakage rate, the single-brick self-weight reference leakage rate The results were obtained through calibration experiments. The calibration experiment method was as follows: a standard lead brick was taken and placed on a standard test bench. A pressure equal to its own weight was applied to the standard lead brick, and the leakage rate between the standard lead brick and the standard test bench was measured. The measured leakage rate was taken as the standard test bench. The logic for determining whether there are physical anomalies in the gaps between each layer is as follows: when When <1, it indicates that the first The interlayer gap is compared to the adjacent gap above it. The stable leakage rate of the interlayer gap decreased, meaning the leakage rate decreased from top to bottom with respect to the interlayer position. This decrease is consistent with the normal compression and sealing effect generated by the cumulative weight of the lead bricks layer by layer, indicating that the structure of the interlayer gap is intact and well-stacked, and there is no abnormal leakage behavior caused by brick damage, misalignment, or foreign object insertion. Therefore, the first interlayer gap is determined to be... There are no physical anomalies in the interlayer gaps; when When ≥1, it indicates that the first... The interlayer gap is compared to the adjacent gap above it. The fact that the stable leakage rate of the interlayer gap did not decrease, or even increased, indicates that there may be structural defects or abnormal conditions in the gap, such as localized damage to the lead bricks, misalignment during stacking, foreign objects trapped in the gap, or uneven brick surfaces leading to poor adhesion. To further quantify the abnormal conditions, a high-precision distance sensor can be installed on the outside of the lead brick stack to continuously monitor the relative displacement between the outer edges of adjacent layers of lead bricks in a non-contact manner. Simultaneously, pre-positioned image sensors can be used to image the gap and the surfaces of adjacent bricks, and image processing algorithms can be used to help identify visible defects such as brick chipping, surface cracks, or foreign object embedding. All of these conditions will affect the sealing performance of the gap, preventing the stable leakage rate from effectively decreasing with increasing weight above. Therefore, the gap is determined to be... If a physical anomaly is found in any interlayer gap, stop the current assessment, disassemble and inspect the gap, remove foreign objects, replace damaged lead bricks or re-stack, and retest after repair. S4: For lead brick stacks where no physical anomalies are found in any interlayer gaps, calculate the leakage rate judgment threshold for each interlayer gap based on the mass data of each lead brick. This judgment threshold reflects the maximum allowable leakage rate of the gap under the compression effect generated by the cumulative weight of the lead bricks above the current gap, i.e., the upper limit of qualified sealing. Compare the stable leakage rate of each interlayer gap with the corresponding leakage rate judgment threshold, and determine whether the sealing of each interlayer gap is qualified based on the comparison result. The formula used to calculate the leakage rate threshold for the interlayer gaps is as follows: in, For the first The threshold for determining the leakage rate of interlayer gaps; The preset baseline leakage rate threshold; For the first The cumulative weight above each interlayer gap is calculated using the following formula: ,in, For the top to bottom Quality data of lead bricks; The baseline mass of the lead brick is the preset value; The preset compression sealing coefficient, and >0; No. The cumulative weight above the interlayer gap The larger the value, the greater the pressure of the lead brick's own weight that the gap bears, the tighter the fit between the lead bricks, and the better the sealing performance of the gap. Therefore, the allowable leakage rate threshold is determined accordingly. The smaller it is, the better. The smaller, The larger the value is, it indicates that when the upper self-weight is relatively light, the compression effect is weak, and the corresponding upper limit of the acceptable leakage rate is increased; said judging whether the sealing performance of each interlayer gap is qualified according to the comparison result has the following judgment logic: when ≤ it indicates that the actual leakage level of the interlayer gap does not exceed the allowable range, and the sealing performance of the -th interlayer gap is judged as qualified; when > it indicates that the stable leakage rate of the interlayer gap has exceeded the upper threshold limit, and the sealing performance fails to meet the requirements, so the sealing performance of the -th interlayer gap is judged as unqualified; For the entire lead brick stack, only when the sealing performance of every interlayer gap is judged as qualified can the overall sealing performance of the lead brick stack be determined as qualified; if there is any interlayer gap with unqualified sealing performance, the overall sealing performance of the lead brick stack is judged as unqualified. All the above formulas are calculated with their numerical values after dimension removal, the formulas are formulas obtained by collecting a large amount of data and performing software simulation to approach the real situation, and the preset parameters in the formulas are set by those skilled in the art according to actual conditions.

[0023] The above embodiments can be implemented entirely or partially by software, hardware, firmware or any other combination. When implemented by software, the above embodiments can be entirely or partially in the form of a computer program product. Those skilled in the art can appreciate that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution.

[0024] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the present embodiment.

[0025] The above is only the specific embodiments of the present application. However, the protection scope of the present application is not limited thereto. Any change or replacement that can be easily conceived by a person skilled in the art within the technical scope disclosed by the present application shall be covered within the protection scope of the present application.

Claims

1. A method for testing the sealing performance of gaps in radiation-shielding lead bricks, characterized in that, Includes the following steps: S1: A sealing test is performed on a pile of lead bricks with multiple interlayer gaps. The pile of lead bricks is formed by stacking multiple lead bricks vertically in a layer-by-layer manner. An independent sealing test chamber is set for each interlayer gap. The mass data of each lead brick and the volume data of each sealing test chamber are obtained. The pressure data and temperature data in each sealing test chamber are collected at fixed time intervals. The collected pressure data and temperature data are preprocessed. S2: Based on the preprocessed pressure and temperature data, calculate the instantaneous leakage rate of each interlayer gap at each sampling time. For each interlayer gap, construct a corresponding leakage rate sliding window and input the instantaneous leakage rate of each interlayer gap into the corresponding leakage rate sliding window. Based on the instantaneous leakage rate within each leakage rate sliding window, calculate the relative fluctuation rate of the leakage rate of each interlayer gap. Based on the relative fluctuation rate of the leakage rate of each interlayer gap, determine whether the leakage rate of each interlayer gap is stable. After determining that it is stable, obtain the stable leakage rate of each interlayer gap. After all interlayer gaps have obtained a stable leakage rate, proceed to step S3. S3: Based on the stable leakage rate of each interlayer gap, calculate the interlayer monotonic coefficient of two adjacent interlayer gaps in order from top to bottom, and determine whether there is a physical anomaly in each interlayer gap based on the interlayer monotonic coefficient. S4: For a pile of lead bricks where there are no physical abnormalities in any of the interlayer gaps, calculate the leakage rate judgment threshold for each interlayer gap based on the quality data of each lead brick, and compare the stable leakage rate of each interlayer gap with the corresponding leakage rate judgment threshold. Determine whether the sealing performance of each interlayer gap is qualified based on the comparison results.

2. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 1, characterized in that: The method used for preprocessing the collected pressure and temperature data is as follows: The preprocessing includes data cleaning and data smoothing filtering; The data cleaning process includes handling outliers and missing values. Statistical methods are used to identify outliers in the pressure and temperature data of each sealed detection chamber, and these outliers are deleted. Linear interpolation is then used to fill in the missing values ​​in the pressure and temperature data of each sealed detection chamber.

3. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 2, characterized in that: The data smoothing and filtering method is as follows: Using the sampling time corresponding to a fixed time interval as the reference time point, an equally spaced reference time axis is constructed. The cleaned pressure data and temperature data are matched with the reference time axis according to their respective original timestamps. For each sealed detection chamber, a pressure data time series and a temperature data time series for each sealed detection chamber are constructed. For each pressure data time series and temperature data time series, a median filter is performed using a one-sided sliding window of length K. The one-sided sliding window consists of the data at the current sampling time and the data at the previous K-1 sampling times, where K is a preset odd number and K≥3.

4. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 1, characterized in that: The formula used to calculate the instantaneous leakage rate of the interlayer gaps at each sampling time is as follows: in, For the first The interlayer gap is Instantaneous leakage rate at any given moment; For the first The interlayer gap is Stress data at any given moment; For the first The interlayer gap is Stress data at any given moment; For the first Volume data of the sealing test chamber corresponding to each interlayer gap; Standard atmospheric pressure; For the first The sealing detection chamber corresponding to each interlayer gap is Temperature data at any given time; This is the preset reference temperature; This is a preset, fixed time interval.

5. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 4, characterized in that: The method for constructing the leakage rate sliding window is as follows: Starting from the current sampling time, backtracking in the reverse direction of time, extract the instantaneous leakage rates corresponding to the most recent W consecutive sampling times to form a leakage rate sliding window, where W is the total number of instantaneous leakage rates in the leakage rate sliding window, and W≥5; after W instantaneous leakage rates have been input into the leakage rate sliding window, when a new instantaneous leakage rate corresponding to a sampling time is input, remove the instantaneous leakage rate corresponding to the earliest sampling time in the leakage rate sliding window, so that the leakage rate sliding window always contains the instantaneous leakage rates corresponding to the most recent W sampling times.

6. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 5, characterized in that: The formula used to calculate the relative fluctuation rate of leakage rate between each layer is as follows: in, for Time of the first The relative volatility of interlayer gap leakage rate; for Time of the first The standard deviation of all instantaneous leakage rates within the sliding window corresponding to the leakage rate of each interlayer gap; for Time of the first The average of all instantaneous leakage rates within the sliding window corresponding to the leakage rate of each interlayer gap; It is a preset positive number used to prevent the denominator from being zero.

7. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 6, characterized in that: The logic for determining whether the leakage rate between each layer is stable is as follows: when < And lasting longer than At that time, the judgment was made. The interlayer leakage rate has stabilized, and the average of all instantaneous leakage rates within the current leakage rate sliding window is used as the first... Stable leakage rate of interlayer gaps ;when ≥ ,or < However, the duration did not exceed At that time, the judgment of the first The leakage rate of interlayer gaps was not stable; among them... The preset time threshold; This is the preset stability threshold.

8. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 1, characterized in that: The formula used to calculate the interlayer monotonicity coefficient of the gap between two adjacent layers is as follows: For the first from top to bottom The interlayer gap is calculated. The interlayer gap and the first Interlayer monotonicity coefficient of each interlayer gap; in, For the first Interlayer monotonicity coefficient of each interlayer gap; For the first The stable leakage rate of the interlayer gap; when At that time, that is, the first interlayer gap from top to bottom, ,in, The preset leakage rate is based on the self-weight of a single brick.

9. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 8, characterized in that: The logic for determining whether there are physical anomalies in the gaps between each layer is as follows: when When <1, determine the first There are no physical anomalies in the interlayer gaps; when When ≥1, determine the first There are physical anomalies in the interlayer gaps.

10. The method for testing the sealing performance of gaps in radiation-shielding lead bricks according to claim 9, characterized in that: The formula used to calculate the leakage rate threshold for the interlayer gaps is as follows: in, For the first The threshold for determining the leakage rate of interlayer gaps; The preset baseline leakage rate threshold; For the first The cumulative weight above each interlayer gap is calculated using the following formula: ,in, For the top to bottom Quality data of lead bricks; The baseline mass of the lead brick is the preset value; The preset compression sealing coefficient, and >0; The judgment logic for determining whether the sealing performance of the gaps between each layer is qualified based on the comparison results is as follows: when ≤ At that time, the judgment of the first The sealing performance of the interlayer gaps is qualified; when > At that time, the judgment of the first The sealing performance of the gaps between individual layers is unqualified; when the sealing performance of all gaps between layers is deemed qualified, the overall sealing performance of the lead brick pile is deemed qualified.

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