A hydraulic valve leak detection system

Abstract

The application discloses a kind of hydraulic valve leakage detection systems, it is related to hydraulic valve leakage detection technical field.The application equipment starts when, system automatically executes equipment internal module loading, completes all parameter initialization;After system initialization is completed, continuously polling detection system control box on control module start button signal, when not detecting button press signal, system keeps standby polling state, continuously monitor button signal, detect start button press signal, officially start whole machine measurement process.This device uses precision weighing module, with 1000 gram range module as an example: precision is 0.01 gram, linearity 0.02 gram, error ±0.03 gram, when actual measurement, oil liquid is minimum drop unit, if using standard drop nozzle, one drop oil is 0.05ml, then through this detection system, can filter less than 0.05ml error, and accurate result can be obtained through algorithm filtering.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic valve leakage detection technology, and in particular relates to a hydraulic valve leakage detection system. Background Technology

[0002] Measuring internal leakage in hydraulic valves has always been a challenge in the industry, primarily due to the wide leakage range. Taking the JB10364-2014 standard as an example: the internal leakage standard for check valves requires ≤0.2ml / min, while the piston leakage of large-diameter hydraulically controlled check valves can reach ≤350ml / min. Manufacturers have even higher requirements for internal leakage standards, with most requiring internal leakage of check valves to be ≤3 drops / min, approximately ≤0.15ml / min. With the improvement of component machining precision, some check valves have achieved internal leakage levels of ≤0.02ml / min and even higher. A measurement range of 0.01-1000ml / min is needed to meet current industry needs.

[0003] Currently, in the field of hydraulic valve leakage measurement, the mainstream methods commonly used in the industry mainly include visual measuring cup measurement, photoelectric measurement, and micro-gear flow meter measurement. However, although these methods have certain practicality within their respective applicable flow ranges, they all have significant limitations: neither visual measuring cup measurement, photoelectric measurement, nor micro-gear flow meter measurement alone can fully cover the precise measurement needs of hydraulic valves across a wide flow range of 0.01 to 1000 ml / min. Furthermore, these traditional measurement methods generally suffer from low measurement accuracy, poor repeatability, and significant susceptibility to interference from human or environmental factors in practical applications, making it difficult to meet the stringent requirements of modern high-precision hydraulic systems for leakage detection. Therefore, under current technological levels, no single measurement method can simultaneously achieve the dual goals of full-range coverage and high-precision measurement. Summary of the Invention

[0004] The purpose of this invention is to provide a hydraulic valve leakage detection system that solves the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0006] 1. A hydraulic valve leakage detection system, comprising the following steps:

[0007] S1. System Initialization: When the equipment is powered on, the system automatically loads the internal modules of the equipment, completes the initialization of all controls and register parameters, and restores them to the default or preset values. The operator can preset the number of detection pressure points at each level, the holding time of a single pressure point, the leakage qualified threshold, and the upper limit of the weighing box volume in the system in advance. After the system initialization is completed, it continuously polls the start button signal of the control module on the system control box. When no button press signal is detected, the system remains in standby polling state and continuously monitors the button signal. After the start button press signal is detected, the whole machine measurement process is officially started.

[0008] S2. Pipeline pretreatment and prepressurization: drain residual oil from the measuring oil circuit, flush the oil circuit and remove air bubbles, then perform pressure preloading, pressurize to weighing mode to determine and set calibration pressure;

[0009] S3, 10s weighing mode judgment setting and zero point tracking calibration; the system starts a 10s timing program, collects the oil weight data of the weighing box in real time and calculates the cumulative leakage volume; continuously judges whether the leakage of the hydraulic valve within 10s is greater than or equal to 0.1mL (i.e. two drops), thereby completing the weighing mode classification judgment.

[0010] If the leakage amount is determined to be ≥0.1mL within 10s, the system will activate the standard weighing mode: enable the creep function of the weighing module, set the filter coefficient of the weighing module to the standard level, and adapt to the conventional leakage detection scenario.

[0011] If the leakage amount is determined to be <0.1mL within 10s, the system will activate the micro-volume slow-change weighing mode: turn off the creep function of the weighing module, reduce the filter coefficient of the weighing module, improve the accuracy of micro-leakage detection, and at the same time, the system will pop up a window to prompt the operator to put the initial weight in the weighing box to complete the zero-point tracking calibration of the weighing module and eliminate the influence of the zero-point tracking of the equipment on micro-volume detection.

[0012] S4. After the target pressure is applied, the weighing mode and zero point are adjusted, the system collects and stores the initial weighing data of the weighing module and the real-time oil temperature of the oil circuit. Then the control system drives the hydraulic unit to increase the pressure to the preset pressure of the current detection level. After the oil circuit pressure stabilizes, the data acquisition module simultaneously collects the initial total weight of the weighing box and the real-time temperature of the pipeline oil and completes accurate recording, which serves as the detection benchmark data for the current pressure point.

[0013] S5. Start the weighing and timing control program. During the pressure holding test cycle, the weighing and oil temperature data are collected in real time. The system cyclically judges whether the delay time is equal to the predetermined test duration. If the duration is not reached, the delay continues until the delay time is equal to the predetermined time. After the timing reaches the predetermined time, the total weight of the weighing box is collected as the end weight of the measurement and the oil temperature are recorded.

[0014] S6. Weighing box oil level determination: The system calculates the cumulative oil level in the box by the difference between the start and end weights and compares it with the preset upper limit of the weighing volume.

[0015] No manual intervention is required when the fuel level is below the maximum limit;

[0016] When the oil level reaches the upper limit, empty the oil from the weighing box, and the control system will automatically perform a zeroing operation on the weighing module.

[0017] After completing the data acquisition of the current pressure point, the system determines whether all preset pressure points have been completed. If not, the pressure is increased to the next level and steps S4 to S6 are repeated. After all pressure points are detected, the pressure is unloaded from the measuring oil circuit.

[0018] S7. Read recorded data and correct oil temperature density coefficient; after the pressure is completely unloaded, read the start and end weight of each pressure segment and the oil temperature range throughout the entire process, and query the built-in oil temperature density coefficient table to complete the density coefficient correction; check if the oil temperature throughout the entire process is 50±4℃. If it exceeds the range, query the oil temperature density coefficient table to correct the density coefficient.

[0019] S8. Weight and volume conversion: Based on the preset calculation formula, combined with the corrected oil density coefficient, weighing data, and detection time, the hydraulic valve leakage volume after the oil temperature density coefficient is accurately calculated.

[0020] S9. Qualification judgment: Compare the leakage amount per unit time with the preset standard threshold, output the qualified / unqualified judgment result of the tested hydraulic valve, and archive and store all test data in a data table. The data table is automatically generated and stored locally or uploaded to the equipment background database.

[0021] S10, data visualization, storage archiving and reset: After a single test is completed, the device does not restart the system initialization program, but directly returns to the standby state of the initial button signal detection, waiting for the next test start command.

[0022] Preferably, the calculation formula used in S7 is: Leakage volume = (real-time weighing data - initial weighing data) ÷ oil density coefficient ÷ weighing time, and the leakage volume parameter per unit time is obtained by calculation.

[0023] Preferably, in S6, when the oil level reaches the upper limit: the terminal pops up a prompt to empty the oil in the weighing box, and after the emptying is completed and confirmed, the weighing is automatically zeroed and the remaining time of the current pressure segment is collected.

[0024] Preferably, the system automatically stores all pressure parameters, weight parameters, oil temperature parameters, calculation parameters, and final judgment results of this test. It automatically draws the PQ curve (i.e., pressure-flow curve) based on the built-in drawing module and displays it on the human-machine interface in real time. At the same time, it generates standardized test reports through the report processing module to complete the visualization and standardized storage of test data.

[0025] The present invention has the following beneficial effects:

[0026] The system of this invention uses a precision weighing module. Taking a 1000-gram weighing module as an example, the accuracy is 0.01 grams, the linearity is 0.02 grams, and the error is ±0.03 grams. In actual measurement, the oil is measured in units of the smallest drop. If a standard dropper is used, one drop of oil is 0.05 ml. Therefore, this detection system can filter out errors smaller than 0.05 ml. Through algorithm filtering, accurate results can be obtained. Furthermore, this precision weighing module uses a conventional industrial product manufactured by Sanjiang Weighing Instrument Co., Ltd., a domestic company. The retail purchase cost for a 0.01-gram accuracy module is around 1000 yuan, and the retail purchase cost for a 0.001-gram accuracy module is around 1800 yuan. The cost is even lower for bulk purchases. Compared to the starting price of 300,000 yuan for a typical hydraulic testing bench, this cost makes it easy to promote and use. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the system operation process of the present invention.

[0029] Figure 2 This is a schematic diagram of the system operation structure of the present invention. Detailed Implementation

[0030] The technical solutions of the present invention will now be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention.

[0031] Please see Figure 1 and Figure 2 As shown, the present invention is a hydraulic valve leakage detection system, comprising the following steps:

[0032] S1. System Initialization and Hardware Setup and Calibration: Before testing, complete the hardware setup and oil circuit connection work, set up and connect the hydraulic measurement oil circuit, place the weighing box directly below the leaking oil pipe to collect the leaking oil, and place the weighing module at the bottom of the weighing box to support the weighing box to complete the accurate weighing operation; the weighing module establishes a data communication connection with the system control box through the serial communication module to ensure real-time transmission of weighing data;

[0033] The system control box integrates a control module, a data acquisition module, a measurement and calculation module, an external communication module, a data storage module, and a report processing module, enabling fully automated control of the testing process, real-time data acquisition, precise calculation and analysis, data transmission and archiving, and report generation.

[0034] The control module is responsible for coordinating the overall operation logic of the testing device and issuing various operation commands according to the preset testing process; the data acquisition module synchronously collects the weight data of the weighing instrument and the working pressure parameters of the valve body, and transmits them to the measurement and calculation module in real time; the measurement and calculation module combines the weight data of the weighing box to calculate the leakage of the hydraulic valve per unit time; the external communication module can transmit the test data to the terminal display device for convenient real-time viewing by operators; the data storage module automatically saves all test process data for easy retrospective verification; the report processing module can automatically generate standardized test reports based on the stored test data, eliminating the need for manual compilation.

[0035] After the hardware setup and wiring are completed, the system is started and automatically enters the overall initialization and calibration process. This completes fully automatic self-testing of each core functional module, including zero-point calibration of the pressure sensor, accuracy calibration of the weighing module, and sensitivity calibration of the oil temperature acquisition module. This effectively eliminates initial hardware errors and ensures the accuracy of subsequent test data from the source. Operators can preset and solidify core test parameters through the equipment's human-machine interface terminal. Parameters can be customized and saved according to the model of the hydraulic valve to be tested and industry testing standards. Specific preset parameters include: the number of multi-level stepped test pressure points, the single pressure holding test duration corresponding to each pressure level, a fixed standard oil temperature range of 50±4℃, the hydraulic valve leakage threshold, and the upper limit value of the weighing box volume. After the parameters are preset, the system automatically enters a standby polling state, continuously monitoring the physical start button signal on the system control box in real time. If no button trigger signal is detected, the system always maintains a low-power standby polling mode.

[0036] Once the operator presses the start button, the fully automatic hydraulic valve leakage measurement process is initiated.

[0037] S2. After the system starts the measurement process, the measurement oil circuit pretreatment procedure is first performed to completely eliminate the interference that residual oil and air bubbles in the oil circuit may cause to the subsequent test results. The system automatically controls the pressure loading and drives the hydraulic oil to circulate and flush in the preset measurement oil circuit to effectively remove the gas accumulated in the pipeline. This circulation flushing process lasts for 5 to 10 seconds to ensure that the inner wall of the oil circuit reaches a highly clean state and that no air bubbles are left behind. Through this pretreatment step, the leakage detection error caused by air bubble compression or accidental dripping of residual oil droplets can be effectively avoided in the subsequent test process.

[0038] After the oil circuit flushing and air bubble removal are completed, the system performs a pressure preload operation to steadily increase the oil circuit pressure to the preset low reference pressure;

[0039] S3, 10s Short-Time Weighing Module Zero-Point Compensation Calibration: After pipeline pretreatment, the system automatically enters the 10s short-time weighing module zero-point compensation calibration process. This is used to predict the basic working conditions of hydraulic valve leakage, adaptively match the working parameters of the weighing module, and significantly improve the detection accuracy of minute leaks. The system starts the high-precision timing module, initiates a 10s countdown detection, and simultaneously collects the cumulative weight of the oil in the weighing box in real time. The cumulative leakage volume is calculated in real time using an internal substitution calculation formula. After the 10s short-time detection ends, the system automatically completes the leakage condition judgment and adapts to the corresponding weighing mode.

[0040] If the cumulative leakage within 10 seconds is greater than or equal to 0.1 mL, it is determined that the hydraulic valve under test has obvious basic leakage. The system automatically activates the creep compensation function of the weighing module and adjusts the filter coefficient of the weighing module to the standard level to adapt to data acquisition scenarios with normal and large leakage, effectively avoiding data fluctuation and distortion, and ensuring the detection stability under large leakage conditions.

[0041] If the system determines that the cumulative leakage is less than 0.1 ml within a 10-second monitoring period, the system will confirm that the hydraulic valve under test is in a minor leakage condition. In this case, the system will automatically turn off the creep compensation function of the weighing module to eliminate the interference of slow creep on instantaneous minor weight changes. At the same time, the system will synchronously reduce the filter coefficient of the weighing module to reduce the delay and smoothing effect caused by signal filtering, thereby significantly improving the weighing module's sensitivity and response speed to extremely minor weight changes.

[0042] Subsequently, the system will prompt the operator through a pop-up window to place standard initial weights in the weighing box to eliminate zero-point tracking. This step aims to completely eliminate zero-point drift caused by factors such as environmental temperature drift, time drift, or residual stress of the sensor, fundamentally avoiding the impact of zero-point error on the accuracy of subsequent leak detection. After calibration, the system will automatically save the calibration parameters and jump to the next detection procedure to continue the subsequent test process.

[0043] S4. After the zero-point compensation calibration is completed, the system enters the stage of precise detection of graded pressure. First, the system collects and locks the initial weighing data of the weighing module. At the same time, the initial oil temperature of the hydraulic oil in the oil circuit is collected in real time through the oil temperature sensor. The two sets of initial data are stored in the register simultaneously as the reference parameters for subsequent leakage calculation.

[0044] The system then drives the pressure unit to steadily increase the pressure. According to the preset pressure level, the oil pressure is precisely increased to the target pressure of the current detection level. The pressure increase process adopts a slow-increase control logic to avoid the pressure surge impacting the valve body under test and the pipeline seals. After the pressure reaches the preset value and the oil pressure and weight data are completely stable, the data acquisition module synchronously collects the initial total weight of the weighing box and the initial oil temperature of the pipeline again, updates and solidifies the benchmark data under the current pressure level, and ensures that the initial parameters of each pressure detection are accurate and effective.

[0045] S5. After the initial data acquisition and solidification are completed, the system starts the weighing and timing control program and enters the pressure holding test cycle. Within the preset single pressure holding time, the weighing data, oil temperature data and oil circuit pressure data are collected in real time and synchronously, and the changes in working conditions are dynamically monitored throughout the process.

[0046] During the test, the system continuously compares the real-time delay time with the preset pressure holding test time. If the real-time time does not reach the preset time, the system continues to maintain a stable voltage state and continuously collects various data until the timed duration and the preset test duration are completely matched.

[0047] When the pressure holding timer reaches the preset time node, the end oil temperature data is collected and recorded, and the start and end detection data of the current pressure level are completely stored.

[0048] S6. After the single pressure setting pressure holding test is completed, the system automatically calculates the cumulative leakage oil volume in the weighing box based on the difference between the start and end weights of this test, and at the same time compares it with the system's preset upper limit value of the weighing box volume to perform differential chemical condition processing.

[0049] If the accumulated oil volume reaches the upper limit of the weighing box during the test, the system will immediately pause the current data acquisition process and issue an oil pouring prompt through a pop-up window. After the operator emptys the oil from the weighing box and confirms the operation on the terminal, the system will automatically execute the zeroing and reset of the weighing module, and then continue to complete the data acquisition work for the remaining time of the current pressure level, ensuring the continuity of the test throughout the process and avoiding oil overflow from affecting the test accuracy.

[0050] If the accumulated oil volume has not reached the upper limit of the capacity, the system will directly complete the collection of all data for the current pressure level without manual intervention.

[0051] After all single-pressure-point testing procedures are completed, the system automatically compares the number of completed pressure points with the preset total number of pressure points to determine whether multi-level testing is complete.

[0052] If all pressure point tests are not completed, the system will smoothly increase the pressure to the next preset test pressure and repeat the above target pressure loading, pressure holding data acquisition, and oil quantity determination procedures (i.e., steps S4 to S6) until all leak tests at all preset pressure levels are completed.

[0053] After all pressure points are tested, the system performs a slow, step-by-step pressure unloading to gradually release the oil pressure, preventing pressure shocks caused by instantaneous pressure relief, effectively protecting the valve body seals, pipelines, and testing fixtures of the hydraulic valve under test, and avoiding fatigue damage to equipment components.

[0054] S7. After the oil pressure is completely unloaded and the pipeline conditions return to a stable state at normal temperature and pressure, the system retrieves the start and end weighing data and real-time oil temperature data corresponding to each pressure level, and calls the built-in oil temperature-density coefficient comparison table to complete the accurate correction of hydraulic oil density. Since the hydraulic oil density fluctuates linearly with oil temperature, it directly affects the accuracy of weight-volume conversion. Therefore, the system uses the real-time detected oil temperature as a benchmark, matches the standard oil density coefficient at the corresponding temperature, replaces the fixed density parameter, and eliminates the conversion error caused by temperature.

[0055] After correction, the system completes the accurate calculation of leakage volume per unit time through the built-in core calculation formula. The specific formula is: Leakage volume = (real-time weighing data - initial weighing data) ÷ oil density coefficient ÷ weighing time. Through this formula, the weight difference is accurately converted into a standardized leakage volume parameter per unit time, which truly reflects the actual leakage performance of the hydraulic valve under test.

[0056] S8. After the leakage calculation is completed, the system performs a full-range judgment on the oil temperature data throughout the detection process to check whether the oil temperature is stable within the standard qualified range of 50±4℃.

[0057] During the testing process, if the oil temperature can be maintained within the specified acceptable range, then all the data collected in this test will be considered true and valid, and can be directly used as an important basis for judging whether the product is qualified.

[0058] If the oil temperature exceeds the acceptable range of 50±4℃ during the test, the system will automatically call up the oil temperature density coefficient reference table again and perform fine density calibration on the oil temperature value that exceeds the standard temperature range to compensate for the leakage calculation error caused by temperature deviation. After the correction process is completed, the system will further verify the validity and consistency of the data to ensure that the test data obtained still maintains a high degree of accuracy and reliability even under non-standard temperature conditions.

[0059] S9. After completing temperature compensation and data validity verification, the system will accurately compare the corrected leakage rate parameter per unit time with the system's preset leakage qualification threshold, and automatically output the qualification or non-qualification result of the hydraulic valve under test. The judgment logic standard is unified and there is no subjective human intervention, which improves the fairness and accuracy of the test.

[0060] After the judgment is completed, the system will summarize and archive all the core data of this test, including the test pressure at each level, the pressure holding time, the oil temperature data throughout the process, the weighing start and end data, the density correction parameters, the converted leakage amount, the final judgment result, etc., and automatically generate standardized data tables. It can realize local equipment storage and also supports automatic data upload to the equipment's backend database to build a test data ledger, realize the full traceability of the test data of each hydraulic valve under test, and meet the requirements of industrial quality inspection traceability management.

[0061] S10. After the data is archived, the system starts the data visualization processing program. Based on the time series data of pressure, oil temperature and leakage during the whole process, it automatically draws the parameter time series change curve and displays it on the human-machine interaction terminal in real time. It intuitively presents the leakage performance change law of the hydraulic valve under test in multiple pressures and the whole process detection cycle, which makes it easy for operators to intuitively judge the product working condition.

[0062] Meanwhile, the system's report processing module automatically generates standardized test reports. These reports include complete information such as test time, equipment number, product model under test, all test parameters, correction data, judgment results, and time-series curves. The reports can be exported, printed, and saved. After completing a test task, the equipment does not need to restart the system initialization program. Instead, it directly returns to the standby state of the initial button signal detection, waiting to receive the next test start command. This allows it to immediately begin leak detection of the next batch of hydraulic valves. This design significantly enhances the equipment's cyclic operation capability and greatly improves the overall testing efficiency.

[0063] This system effectively solves the problems of poor leakage detection accuracy, numerous working condition interferences, lack of data basis, and easy damage to workpieces in traditional hydraulic valves by multi-level pressure segment detection, dynamic oil temperature correction, adaptive adjustment of weighing parameters, anti-impact pressure relief, and full data traceability design. The detection accuracy can reach up to 0.0012mL level, which fully meets the factory quality inspection and performance verification requirements of high-precision hydraulic valves.

[0064] This system is designed for the accurate detection of leakage in conventional industrial hydraulic valves. It is suitable for factory testing, rework verification, and sampling quality inspection of various specifications of hydraulic valves such as directional valves, relief valves, and throttle valves. The entire process is automated, with temperature compensation correction, accurate data judgment, and visual archiving. It effectively solves industry pain points such as low leakage detection accuracy, high susceptibility to oil temperature interference, lack of data traceability, and valve body damage caused by pipeline pressure shocks.

[0065] This system adopts the mature SJ110B series high-precision weighing sensor module, equipped with RS232 / RS485 serial communication module, and supports MODBUS-RTU communication protocol. The system control box is a hydraulic valve comprehensive testing system developed using the LabVIEW language platform, with built-in weighing algorithm. Taking a 1000-gram weighing module as an example: accuracy is 0.01 grams, linearity is 0.02 grams, and error is ±0.03 grams. In actual measurement, the oil is measured in units of the smallest drop. If a standard dropper is used, one drop of oil is 0.05 ml (taking 46# hydraulic oil as an example). Through the control of this system, errors smaller than 0.05 ml can be filtered out. The algorithm filtering can obtain accurate results. At the same time, this system uses the weighing number minus the initial weighing number, so there is no need to consider the weight of the container, the weight of the weights, the residue on the container wall, cumulative errors, and many other issues. The measurement accuracy is equal to the accuracy of the steady-state module. Currently, the highest accuracy of this series of modules is 0.001 grams, which is equivalent to 0.0012 ml of volume.

[0066] The above are merely preferred embodiments of the present invention and do not limit the present invention. Any modifications, equivalent substitutions, or improvements made to the technical solutions described in the foregoing embodiments, or to some of the technical features, shall fall within the protection scope of the present invention.

Claims

1. A hydraulic valve leakage detection system, characterized in that, Includes the following steps: S1. System Initialization: When the equipment is powered on, the system automatically loads internal modules and completes the initialization of all parameters. The number of detection pressure points at each level, the holding time of a single pressure point, the leakage acceptance threshold, and the upper limit of the weighing box volume are preset in the system in advance. After the system initialization is completed, the start button is detected and the whole machine measurement process is officially started. S2. Pipeline pretreatment and prepressurization: The residual oil in the measuring oil circuit is drained, the oil circuit is flushed and air bubbles are removed, and then pressure preloading is performed to increase the pressure to the weighing mode to determine the set calibration pressure. S3, 10s Weighing Mode Judgment Setting and Zero Point Tracking Calibration: The system starts a 10s timing program, collects the oil weight data of the weighing box in real time and calculates the cumulative leakage volume; continuously judges whether the leakage of the hydraulic valve within 10s is greater than or equal to 0.1mL, thereby completing the weighing mode classification judgment. If the leakage amount is determined to be ≥0.1mL within 10s, the system will activate the standard weighing mode: enable the creep function of the weighing module, set the filter coefficient of the weighing module to the standard level, and adapt to the conventional leakage detection scenario. If the leakage amount is determined to be <0.1mL within 10s, the system will activate the micro-volume slow-change weighing mode: turn off the creep function of the weighing module, reduce the filter coefficient of the weighing module, improve the accuracy of micro-leakage detection, and at the same time, the system will pop up a window to prompt the operator to put the initial weight in the weighing box to complete the zero-point tracking calibration of the weighing module and eliminate the influence of the zero-point tracking of the equipment on micro-volume detection. S4. Target pressure loading: After the weighing mode and zero point calibration are completed, the system collects and stores the initial weighing data of the weighing module and the real-time oil temperature of the oil circuit; then the control system drives the hydraulic unit to increase the pressure to the preset pressure of the current detection gear. After the oil circuit pressure stabilizes, the data acquisition module simultaneously collects the initial total weight of the weighing box and the real-time temperature of the pipeline oil and completes accurate recording, which serves as the detection benchmark data for the current pressure point. S5. Start the weighing and timing control program: During the pressure holding test cycle, the weighing and oil temperature data are collected in real time. The system cyclically judges whether the delay time is equal to the predetermined test duration. If the duration is not reached, the delay continues until the delay time is equal to the predetermined time. After the timing reaches the predetermined time, the total weight of the weighing box is collected synchronously as the end weight of the measurement and the oil temperature are recorded. S6. Weighing box oil level determination: The system calculates the cumulative oil level in the box by the difference between the start and end weights and compares it with the preset upper limit of the weighing volume. No manual intervention is required when the fuel level is below the maximum limit; When the oil level reaches the upper limit, empty the oil from the weighing box, and the control system will automatically perform a zeroing operation on the weighing module. After completing the data acquisition of the current pressure point, the system determines whether all preset pressure points have been completed. If not, the pressure is increased to the next level and steps S4 to S6 are repeated. After all pressure points are detected, the pressure is unloaded from the measuring oil circuit. S7. Read recorded data and correct oil temperature density coefficient: After the pressure is completely unloaded, read the start and end weight of each pressure segment and the oil temperature range throughout the entire process, and query the built-in oil temperature density coefficient table to complete the density coefficient correction; check whether the oil temperature throughout the entire process is 50±4℃. If it exceeds the range, query the oil temperature density coefficient table to correct the density coefficient. S8. Weight and volume conversion: Based on the preset calculation formula, combined with the corrected oil density coefficient, weighing data, and detection time, the leakage volume of the hydraulic valve after the oil temperature density coefficient is accurately calculated. S9. Pass / Fail Judgment: Compare the leakage amount per unit time with the preset standard threshold, output the pass / fail judgment result of the tested hydraulic valve, and archive and store all test data in a data table. The data table is automatically generated and stored locally or uploaded to the equipment's backend database. S10, Data Visualization, Storage Archiving and Reset: After a single test is completed, the device does not restart the system initialization program, but directly returns to the standby state of the initial button signal detection, waiting for the next test start command.

2. The hydraulic valve leakage detection system according to claim 1, characterized in that, The calculation formula used in S7 is: Leakage volume = (real-time weighing data - initial weighing data) ÷ oil density coefficient ÷ weighing time, which calculates the leakage volume parameter per unit time.

3. The hydraulic valve leakage detection system according to claim 1, characterized in that, In S6, when the oil level reaches the upper limit: a pop-up window on the terminal prompts you to empty the oil in the weighing box. After the emptying is completed and confirmed, the weighing is automatically zeroed and the remaining time for the current pressure segment is collected.

4. The hydraulic valve leakage detection system according to claim 3, characterized in that, In S10, the system automatically stores all pressure parameters, weight parameters, oil temperature parameters, calculation parameters, and final judgment results of this test. It automatically draws the PQ (pressure-flow curve) using the built-in drawing module and displays it on the human-machine interface in real time. At the same time, it generates standardized test reports through the report processing module, completing the visualization and standardized storage of test data.

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