Method for detecting sealing performance of oil filter

Abstract

The invention discloses a method for detecting the sealing performance of an oil filter, relates to the technical field of oil filters, and solves the problems that the design of a detection process is relatively simple, a mode of directly monitoring pressure drop after single-stage pressurization is mostly adopted, and whether the filter leaks or a tool is poor in sealing is difficult to distinguish. According to the invention, through the progressive detection logic of an inflation stage, a voltage stabilization stage and a detection stage, accurate identification of leakage of different degrees is realized; the problem of large leakage or incomplete sealing of the filter can be quickly captured through time clustering characteristics and trend analysis of a pressure rising curve in the inflation stage, and subsequent invalid detection is avoided; in the pressure stabilizing stage, through high-frequency pressure difference value monitoring, tool installation sealing performance and no obvious leakage state of the filter are verified, and interference of the detection environment and tool factors is eliminated; and in the detection stage, high-frequency data acquisition and abrupt rise and abrupt drop trend analysis are carried out at 10 times per second, and tiny leakage is accurately detected.

Description

Technical Field

[0001] This invention relates to the field of oil filter technology, specifically to a method for testing the sealing performance of an oil filter. Background Technology

[0002] The oil filter is a key component that ensures the normal operation of the engine. Its sealing performance directly affects the oil filtration efficiency. If there is a leakage problem, unfiltered impurities will enter the engine lubrication system, leading to accelerated wear of parts and, in severe cases, engine failure.

[0003] Therefore, sealing performance testing is an indispensable quality inspection step in the production process of oil filters. However, existing sealing performance testing technologies have many limitations: on the one hand, the testing process is relatively simple, often using a single-stage pressurization followed by direct monitoring of pressure drop, making it difficult to distinguish whether the leak is caused by the filter itself or by external factors such as poor tooling sealing or environmental interference, leading to misjudgments; on the other hand, the ability to identify the degree of leakage is insufficient, either failing to quickly identify obvious large leaks, resulting in a waste of testing resources, or having low sensitivity to detect minor leaks, leading to defective products entering the market. Meanwhile, existing methods lack a systematic anomaly analysis and data traceability mechanism. When anomalies are detected, technicians struggle to quickly pinpoint the root cause, hindering timely optimization of production processes. To address these industry pain points, there is an urgent need for a robust, accurate, interference-resistant, and traceable method for sealing inspection.

[0004] The oil filter sealing performance testing method provided in this application significantly improves the accuracy, efficiency, and adaptability of sealing performance testing through refined design and intelligent analysis of the three stages of inflation, pressure stabilization, and testing, providing reliable technical support for the quality control of oil filters. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for testing the sealing performance of oil filters. This method solves the problem that the testing process is relatively simple and often uses a single-stage pressurization followed by direct monitoring of pressure drop, making it difficult to distinguish whether the problem is a leak in the filter itself or a problem with the tooling seal.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for testing the sealing performance of an oil filter, comprising the following steps: Step 1, Inflation Stage: Open the inflation valve to allow compressed air to enter the filter after being reduced to the set pressure via the pressure regulating valve. Real-time pressure data is collected and displayed as an upward curve. By analyzing the pressure changes on the upward curve, the normality of the inflation stage is assessed. The specific method is as follows: According to the set pressure, compressed air is gradually delivered into the filter, and the internal pressure value of the filter is monitored in real time. A pressure value change curve is generated in real time. The horizontal axis of this curve is the time line, and the vertical axis is the pressure value. The time value is monitored in real time from the pressure value change curve, and the confirmation process is initiated when the time value reaches a set threshold. Identify the pressure value YL associated with the current moment from the pressure value change curve, and determine whether the pressure value YL satisfies: YL ≥ 0.3 MPa. If the conditions are met, continue inflation until the pressure value YL associated with the subsequent time reaches 0.4 MPa and then stop. If not met, check whether the time value can be met within the time period between 1.5 times the set threshold and 2 times the set threshold. If met, execute the trend analysis process. If not met, generate an inflation failure signal for display. Step 2, Pressure Stabilization Stage: Close the inflation valve, monitor the pressure values ​​associated with the filter using the detector, and calculate the pressure difference between two adjacent pressure values. Analyze whether the pressure difference meets the standard to assess whether the pressure stabilization stage test has passed. The specific method is as follows: The pressure values ​​monitored every 0.5 seconds are recorded and sorted. From the sorted pressure value sequence, the pressure difference between two adjacent pressure values ​​is determined, and the pressure difference is ≥0. The system assesses whether all pressure differences meet the following condition: pressure difference ≤ 0.5 kPa. If so, the pressure stabilization test is considered successful; otherwise, a pressure stabilization test failure signal is generated and displayed. Step 3, Testing Phase: After the pressure is stabilized and qualified, the pressure sensor collects pressure data to form a continuous pressure-time curve. The difference between the real-time collected pressure value and the initial pressure value is checked, and the cumulative pressure drop is recorded simultaneously. The pressure-time curve is used to comprehensively evaluate whether there is a sharp increase or decrease in pressure during the rising or falling phases. The specific method is as follows: Determine the pressure-time curve generated during the testing phase, and record the pressure value associated with the successful completion of the pressure stabilization phase test. Use this pressure value as the standard pressure value, and calibrate the different pressure values ​​YL associated with different times within the pressure-time curve. k Where k represents different times, it will satisfy: |Standard pressure value - YL k | Pressure values ​​≥3kPa are recorded as undetermined pressure values, and the numerical points associated with the undetermined pressure values ​​are marked on the pressure-time curve and recorded as undetermined pressure points. Five consecutive pressure values ​​associated with the front end of the pressure point to be determined are determined, and the five pressure values ​​are sorted in chronological order. After sorting, the difference between the pressure value of the next group and the pressure value of the previous group is determined. The average of the five differences associated with the five pressure values ​​is processed and recorded as the average feature T1. The difference between the pressure point to be determined and the pressure value of the previous group is then confirmed and recorded as the value to be verified D1. Identify whether D1 and T1 satisfy the condition: |D1|≥1.5×|T1|. If satisfied, a leakage signal is generated and displayed directly. If not satisfied, other undetermined pressure points are continuously analyzed. If all undetermined pressure points fail to meet the condition, a qualified detection signal is generated and displayed. Otherwise, a leakage signal is generated and displayed directly.

[0007] Preferably, the trend analysis process specifically includes: Within the pressure value change curve, a portion of the curve segment with time values ​​between 1.5 times and 2 times the set threshold is extracted, and this extracted portion of the curve segment is recorded as the segment to be analyzed. Within the undetermined analysis segment, determine the changing trend between curve points at adjacent time points. Assume the pressure value at the previous time point is YL1 and the pressure value at the next time point is YL2, with the changing trend being (YL2 - YL1). Then, perform characteristic analysis on the confirmed sets of changing trends: Sort the associated sets of changing trends according to the direction of the pressure value changing curves, confirm the trend sequence, randomly select one set of changing trends as the calibration trend, denote the changing trends associated with the front end of the calibration trend as the preceding trend, and denote the changing trends associated with the rear end of the calibration trend as the following trend. The trend is recorded as the subsequent trend. The average of the preceding and subsequent trends is used to confirm the standard trend. The trend difference between the standard trend and the calibrated trend is identified, and the trend difference is ≥0. If the trend difference is >Y1, the calibrated trend is recorded as an abnormal trend. Otherwise, no marking is performed. Y1 is a preset value. The curve segment associated with the abnormal trend is recorded as an abnormal segment. Several groups of abnormal segments in the undetermined analysis segment are determined in sequence, and the line length ratio of the abnormal segment in the undetermined analysis segment is recorded. The line length ratio = the line length of the abnormal segment ÷ the line length of the undetermined analysis segment. If the line length ratio is ≥0.2, an inflation failure signal will be generated and displayed directly. If the line length ratio is <0.2, inflation will continue, and the compressed air pressure will be increased in the subsequent inflation process until the pressure value YL associated with the subsequent time reaches 0.4MPa and then stops.

[0008] Preferably, the increase in compressed air pressure does not exceed 20%.

[0009] Preferably, the voltage stabilization phase lasts for 4 seconds and the detection phase lasts for 10 seconds.

[0010] This invention provides a method for testing the sealing performance of an oil filter. Compared with the prior art, it has the following advantages: This invention achieves accurate identification of leaks of different degrees through a progressive detection logic of "inflation stage - pressure stabilization stage - detection stage". In the inflation stage, the time clustering characteristics and trend analysis of the pressure rise curve can quickly capture large leaks or incomplete sealing problems of the filter, avoiding subsequent invalid detection. In the pressure stabilization stage, high-frequency pressure difference monitoring verifies the sealing performance of the tooling installation and the absence of obvious leaks in the filter, eliminating interference from the detection environment and tooling factors. In the detection stage, high-frequency data acquisition at 10 times / second and analysis of steep increase and decrease trends accurately detect minute leaks, solving the pain point of insufficient sensitivity of traditional detection for minute leaks. The three stages work together to form a complete detection closed loop of "coarse inspection - verification - fine inspection", ensuring that leak identification is thorough and without misjudgment. During the inflation phase, trend sequence analysis of the pressure rise curve is introduced. By calculating the difference between the calibrated trend and the standard trend and statistically analyzing the proportion of abnormal segments, quantitative judgment of inflation anomalies is achieved, avoiding reliance on subjective human judgment. During the pressure stabilization phase, automatic comparison of adjacent pressure differences and threshold verification quickly output pressure stabilization compliance results. During the detection phase, based on the difference verification between the standard pressure value and the real-time pressure value and the average value analysis of the change difference, the system automatically identifies steep increases and decreases and generates leakage signals. The entire process requires no manual intervention in data calculation and trend judgment, improving detection efficiency by more than 30% compared to traditional manual monitoring, while reducing human error and ensuring the consistency and reliability of detection results. During the inflation phase, a buffer analysis interval of 1.5 to 2 times the set threshold is set to address the differences in pressure attainment time. The trend analysis process determines whether inflation can continue, and allows for an increase in compressed air pressure (not exceeding 20%) under specific conditions to adapt to the inflation characteristics of filters with different volumes and interface types. During the pressure stabilization phase, a clear abnormal handling procedure is established, and problems are investigated layer by layer from dimensions such as environment, tooling, and sealing rings to reduce the probability of test interruption caused by external factors. During the detection phase, the average characteristics of multiple pressure values ​​are compared to avoid misjudgments caused by fluctuations in a single data point. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the method flow of the present invention. Detailed Implementation

[0012] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0013] As a first embodiment of this application, see [reference] Figure 1 This application provides a method for testing the sealing performance of an oil filter, comprising the following steps: Step 1: Perform the inflation stage: Place the filter into the sealed fixture, start the fixture clamp, completely seal the filter's inlet and outlet ports, open the inflation valve, and allow compressed air to enter the filter after being reduced to the set pressure (0.3-0.4MPa) by the pressure regulating valve. The pressure sensor collects pressure data in real time and displays the rising curve on the interface. The pressure value change status of the rising curve is displayed on the analysis interface to assess whether the inflation stage is normal. If it is normal, proceed to the subsequent test steps. If it is not normal, turn off the air source, check whether the fixture and filter interface are completely fitted, whether the sealing ring is misaligned, and observe whether there are obvious bulges or damages on the filter shell. Step 2, Pressure Stabilization Phase: Close the inflation valve. Monitor the pressure value associated with the filter every 0.5 seconds using the detector, and calculate the pressure difference between two adjacent pressure values. Analyze whether the pressure difference meets the standard to determine if the pressure stabilization phase test is successful. If it does, proceed to the next testing phase. If it does not meet the standard, first check if there is direct airflow or sudden temperature change in the testing environment (such as an air conditioner vent directly facing the equipment). Then, retighten the tooling fixture. If the problem persists, replace the tooling seal and try again to avoid misjudgment due to tooling seal failure. The pressure stabilization phase lasts for 4 seconds. Step 3, Execution of the detection phase: After the pressure is stabilized and qualified, the detector switches to the detection mode. The pressure sensor collects pressure data at a frequency of 10 times / second to form a continuous pressure-time curve. The difference between the real-time collected current pressure value and the initial pressure value is checked, and the cumulative pressure drop is recorded simultaneously. Within the pressure-time curve, it is comprehensively evaluated whether there is a sharp increase or decrease in the pressure value during the rising or falling phase. If so, a leakage signal is generated and displayed. If not, a qualified detection signal is generated and displayed. The detection phase lasts for 10 seconds. Specifically, the oil filter needs to go through three stages during the testing and processing process: the inflation stage, the pressure stabilization stage, and the testing stage. In the inflation stage, the time required for the internal air pressure of the corresponding filter to reach the set value is evaluated. According to the set air pressure parameters and the internal volume of the corresponding filter, the time is generally in a relatively clustered stage. Based on this characteristic, it is confirmed whether the corresponding filter has any leakage or incomplete sealing. During the pressure stabilization phase, the stability of the internal air pressure of the filter is assessed after inflation. If the stability is up to standard, then the filter installation process is considered up to standard or the filter does not show any obvious leakage. During the testing phase, minute leaks in the filter are precisely detected. Based on the changes in the corresponding air pressure inside the filter over time, the overall leakage status of the filter is assessed, ensuring the overall airtightness of the filter is effectively tested.

[0014] As a second embodiment of this application, based on the first embodiment, a comprehensive analysis is performed on the pressure rise curve associated with the inflation stage to assess whether the inflation stage is normal. In step one, the specific method for assessing whether the inflation stage is normal is as follows: According to the set pressure, compressed air is gradually delivered into the filter, and the internal pressure value of the filter is monitored in real time. A pressure value change curve is generated in real time. The horizontal axis of this curve is the time line, and the vertical axis is the pressure value. The time value is confirmed in real time from the pressure value change curve (the opening time of the inflation valve is recorded as the initial time, and the current time is the associated time generated in real time from the pressure value change curve; the time difference between the two sets of times is the corresponding time value). The confirmation process is started when the time value reaches the set threshold (generally 2-3 seconds). Identify the pressure value YL associated with the current moment from the pressure value change curve, and determine whether the pressure value YL satisfies: YL ≥ 0.3 MPa. If the conditions are met, continue inflation until the pressure value YL associated with the subsequent time reaches 0.4 MPa and then stop. If not met, check whether the time value can be met within the time period between 1.5 times the set threshold and 2 times the set threshold. If met, execute the trend analysis process. If not met, generate an inflation failure signal for display. When relevant external personnel see an inflation failure signal, they need to check the tooling, seals, and whether the filter housing is abnormal. The specific methods of trend analysis are as follows: Within the pressure value change curve, a portion of the curve segment with time values ​​between 1.5 times and 2 times the set threshold is extracted, and this extracted portion of the curve segment is recorded as the segment to be analyzed. Within the undetermined analysis segment, determine the changing trend between curve points at adjacent time points. Assume the pressure value at the previous time point is YL1 and the pressure value at the next time point is YL2, with the changing trend = (YL2 - YL1). Then, perform characteristic analysis on the confirmed sets of changing trends: Sort the associated sets of changing trends according to the direction of the pressure value changing curves, confirm the trend sequence, randomly select one set of changing trends and record it as the calibration trend. Record the changing trends associated with the front end of the calibration trend as the preceding trend, and the changing trends associated with the back end of the calibration trend as the following trend. The trend is averaged with the subsequent trend to confirm the standard trend. The trend difference between the calibrated trend and the standard trend is identified, and the trend difference is ≥0. If the trend difference is >Y1, the calibrated trend is recorded as an abnormal trend. Otherwise, no marking is performed. Y1 is a preset value, and its specific value is determined by the operator based on experience. Generally, it is set to 2. The curve segment associated with the abnormal trend is recorded as the abnormal segment. Several groups of abnormal segments in the analysis segment to be determined are determined in sequence, and the line length ratio of the abnormal segment in the analysis segment to be determined is recorded. The line length ratio = the line length of the abnormal segment ÷ the line length of the analysis segment to be determined. If the line length ratio is ≥0.2, an inflation failure signal will be generated and displayed directly. If the line length ratio is <0.2, inflation will continue, and the compressed air pressure will be increased in the subsequent inflation process, with the increase ratio not exceeding 20%, until the pressure value YL associated with the subsequent time reaches 0.4MPa and then stops. Specifically, if the inflation time is too long during the inflation process, it indicates an abnormality. To identify such abnormalities, the pressure change curve is analyzed within the set time period. The curve segments with slow or abnormal trends are analyzed, and the proportion of the corresponding curve segments is determined. This is used to comprehensively assess whether the filter is in a normal state during the inflation stage.

[0015] As a third embodiment of this application, based on the first embodiment, a comprehensive analysis is performed on the pressure change characteristics associated with the pressure stabilization phase to assess whether the pressure stabilization phase is normal. In step two, the specific method for evaluating whether the voltage stabilization stage test meets the standards is as follows: The pressure values ​​monitored every 0.5 seconds are recorded and sorted. From the sorted pressure value sequence, the pressure difference between two adjacent pressure values ​​is determined, and the pressure difference is ≥0 (that is, the absolute value processing process is required in the difference processing process). The test assesses whether all pressure differences meet the following condition: pressure difference ≤ 0.5 kPa. If so, the pressure stabilization test is considered successful. If not, a pressure stabilization test failure signal is generated and displayed. Based on the pressure stabilization test failure signal, external personnel conduct relevant tests on the filter's test environment, direct airflow, and tooling fixtures.

[0016] As a fourth embodiment of this application, based on the first embodiment, a comprehensive analysis is performed on the pressure-time curve associated with the detection stage to assess whether the detection stage is normal; In step three, the specific method for confirming whether there is a sharp increase or decrease in the detection phase is as follows: Determine the pressure-time curve generated during the testing phase, and record the pressure value associated with the successful completion of the pressure stabilization phase test. Use this pressure value as the standard pressure value, and calibrate the different pressure values ​​YL associated with different times within the pressure-time curve. k Where k represents different times, it will satisfy: |Standard pressure value - YL k | Pressure values ​​≥3kPa are recorded as undetermined pressure values, and the numerical points associated with the undetermined pressure values ​​are marked on the pressure-time curve and recorded as undetermined pressure points. Five consecutive pressure values ​​associated with the front end of the pressure point to be determined are identified, and the five pressure values ​​are sorted in chronological order. After sorting, the difference between the pressure value of the next group and the pressure value of the previous group is determined (i.e., the pressure value of the next group minus the pressure value of the previous group). The average of the five differences associated with the five pressure values ​​is then processed and recorded as the average characteristic T1. The difference between the pressure point to be determined and the pressure value of the previous group (i.e., the last pressure value of the five groups) is then confirmed and recorded as the value to be verified D1. The system identifies whether D1 and T1 satisfy the condition |D1|≥1.5×|T1|. If satisfied, a leak signal is generated and displayed (because under normal circumstances, there will be no sudden increase or decrease in pressure; if such a state occurs, it indicates that the corresponding filter itself has a leak problem). If not satisfied, the system continues to analyze other pending pressure points. If all pending pressure points fail to meet the condition, a qualified test signal is generated and displayed; otherwise, a leak signal is generated and displayed. Specifically, during parameter monitoring, if the corresponding curve is operating normally and the fluctuation is relatively stable, then the corresponding filter is in a relatively stable state during testing. If the fluctuation is violent or abnormal, it means that the corresponding filter has a corresponding leakage abnormality during testing, and a corresponding leakage signal needs to be generated and displayed in a timely manner.

[0017] Some of the data in the above formulas are numerical calculations with dimensions removed, and the contents not described in detail in this specification are all prior art known to those skilled in the art.

[0018] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A method for testing the sealing performance of an oil filter, characterized in that, Includes the following steps: Step 1, Inflation Stage: Open the inflation valve to allow compressed air to enter the filter after being reduced to the set pressure by the pressure regulating valve. Collect pressure data in real time and display the rising curve. By analyzing the pressure value change status of the rising curve, assess whether the inflation stage is normal. Step 2, Pressure Stabilization Stage: Close the air valve, monitor the pressure value associated with the filter using the detector, and calculate the pressure difference associated with two sets of pressure values ​​at adjacent times. Analyze whether the pressure difference meets the standard to determine whether the pressure stabilization stage test meets the standard. Step 3, Testing Stage: After the pressure is stabilized and qualified, the pressure sensor collects pressure data to form a continuous pressure-time curve. The difference between the real-time collected current pressure value and the initial pressure value is checked, and the cumulative pressure drop is recorded synchronously. Within the pressure-time curve, it is comprehensively evaluated whether there is a sharp increase or decrease in the pressure value during the rising or falling phase.

2. The method for testing the sealing performance of an oil filter according to claim 1, characterized in that, In step one, the pressure is set to 0.3-0.4 MPa, and the specific value is determined in advance. If the inflation stage test is normal, the subsequent test steps are executed. If it is not normal, the inflation failure signal is displayed.

3. The method for testing the sealing performance of an oil filter according to claim 2, characterized in that, In step one, the specific method for assessing whether the inflation stage is normal is as follows: According to the set pressure, compressed air is gradually delivered into the filter, and the internal pressure value of the filter is monitored in real time. A pressure value change curve is generated in real time. The horizontal axis of this curve is the time line, and the vertical axis is the pressure value. The time value is monitored in real time from the pressure value change curve, and the confirmation process is initiated when the time value reaches a set threshold. Identify the pressure value YL associated with the current moment from the pressure value change curve, and determine whether the pressure value YL satisfies: YL ≥ 0.3 MPa. If the conditions are met, continue inflation until the pressure value YL associated with the subsequent time reaches 0.4 MPa and then stop. If the condition is not met, check whether the time value can be met within the time period between 1.5 times the set threshold and 2 times the set threshold. If it is met, execute the trend analysis process. If it is not met, generate an inflation failure signal for display.

4. The method for testing the sealing performance of an oil filter according to claim 3, characterized in that, The trend analysis process specifically includes: Within the pressure value change curve, a portion of the curve segment with time values ​​between 1.5 times and 2 times the set threshold is extracted, and this extracted portion of the curve segment is recorded as the segment to be analyzed. Within the undetermined analysis segment, determine the changing trend between curve points at adjacent time points. Assume the pressure value at the previous time point is YL1 and the pressure value at the next time point is YL2, with the changing trend being (YL2 - YL1). Then, perform characteristic analysis on the confirmed sets of changing trends: Sort the associated sets of changing trends according to the direction of the pressure value changing curves, confirm the trend sequence, randomly select one set of changing trends as the calibration trend, denote the changing trends associated with the front end of the calibration trend as the preceding trend, and denote the changing trends associated with the rear end of the calibration trend as the following trend. The trend is recorded as the subsequent trend. The average of the preceding and subsequent trends is used to confirm the standard trend. The trend difference between the standard trend and the calibrated trend is identified, and the trend difference is ≥0. If the trend difference is >Y1, the calibrated trend is recorded as an abnormal trend. Otherwise, no marking is performed. Y1 is a preset value. The curve segment associated with the abnormal trend is recorded as an abnormal segment. Several groups of abnormal segments in the undetermined analysis segment are determined in sequence, and the line length ratio of the abnormal segment in the undetermined analysis segment is recorded. The line length ratio = the line length of the abnormal segment ÷ the line length of the undetermined analysis segment. If the line length ratio is ≥0.2, an inflation failure signal will be generated and displayed directly. If the line length ratio is <0.2, inflation will continue, and the compressed air pressure will be increased in the subsequent inflation process until the pressure value YL associated with the subsequent time reaches 0.4MPa and then stops.

5. The method for testing the sealing performance of an oil filter according to claim 4, characterized in that, The increase in compressed air pressure shall not exceed 20%.

6. The method for testing the sealing performance of an oil filter according to claim 1, characterized in that, In step two, the specific method for evaluating whether the voltage stabilization stage test meets the standards is as follows: The pressure values ​​monitored every 0.5 seconds are recorded and sorted. From the sorted pressure value sequence, the pressure difference between two adjacent pressure values ​​is determined, and the pressure difference is ≥0. The system assesses whether all pressure differences meet the following condition: pressure difference ≤ 0.5 kPa. If so, the pressure stabilization test is considered successful; otherwise, a pressure stabilization test failure signal is generated and displayed.

7. The method for testing the sealing performance of an oil filter according to claim 1, characterized in that, In step three, the specific method for confirming whether there is a sharp increase or decrease in the detection phase is as follows: Determine the pressure-time curve generated during the testing phase, and record the pressure value associated with the successful completion of the pressure stabilization phase test. Use this pressure value as the standard pressure value, and calibrate the different pressure values ​​YL associated with different times within the pressure-time curve. k Where k represents different times, it will satisfy: |Standard pressure value - YL k | Pressure values ​​≥3kPa are recorded as undetermined pressure values, and the numerical points associated with the undetermined pressure values ​​are marked on the pressure-time curve and recorded as undetermined pressure points. Five consecutive pressure values ​​associated with the front end of the pressure point to be determined are determined, and the five pressure values ​​are sorted in chronological order. After sorting, the difference between the pressure value of the next group and the pressure value of the previous group is determined. The average of the five differences associated with the five pressure values ​​is processed and recorded as the average feature T1. The difference between the pressure point to be determined and the pressure value of the previous group is then confirmed and recorded as the value to be verified D1. Identify whether D1 and T1 satisfy the condition: |D1|≥1.5×|T1|. If satisfied, a leakage signal is generated and displayed directly. If not satisfied, other undetermined pressure points are continuously analyzed. If all undetermined pressure points fail to meet the condition, a qualified detection signal is generated and displayed. Otherwise, a leakage signal is generated and displayed directly.

8. The method for testing the sealing performance of an oil filter according to claim 1, characterized in that, The voltage stabilization phase lasts for 4 seconds, and the detection phase lasts for 10 seconds.

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