A cooling tower expansion tank internal leakage detection method and a cooling tower expansion tank

Abstract

The application provides a cooling tower expansion water tank internal leakage detection method and a cooling tower expansion water tank, and relates to the technical field of cooling tower expansion water tank detection. The cooling tower expansion water tank internal leakage detection method detects the upper cavity of the cooling tower expansion water tank and the lower cavity of the cooling tower expansion water tank after the completion of the manufacturing of the cooling tower expansion water tank. Through four steps of liquid injection, pressure extraction, pressure maintenance and detection and judgment, the internal leakage of the internal cavity of the measured cooling tower expansion water tank is quickly judged according to the preset pressure value. Compared with the limitations and complexity of the conventional cooling tower expansion water tank internal leakage detection method, the cooling tower expansion water tank internal leakage detection method has higher universality, saves manpower and detection time, improves the product detection efficiency and correctness, and increases the operation reliability and safety of the railway locomotive equipment parts.

Description

Technical Field

[0001] This invention relates to the field of cooling tower expansion tank detection technology, and particularly to a method for detecting internal leakage in a cooling tower expansion tank and the cooling tower expansion tank itself. Background Technology

[0002] The expansion tank of a cooling tower is a crucial component in railway locomotives used to compensate for volume changes in the cooling medium caused by temperature variations in the cooling water system. It also plays a vital role in stabilizing system pressure. Typically, the expansion tank consists of an upper chamber and a lower chamber, which are sealed and separated from each other. During operation, the upper chamber is filled with cooling medium, while the lower chamber's liquid level is indicated by a level indicator. A portion of the lower chamber is empty to balance the volume changes of the cooling medium.

[0003] After the cooling tower expansion tank is manufactured, the sealing performance between the upper and lower cavities must be tested. If there are leaks or sealing defects between the upper and lower cavities of the cooling tower expansion tank, it may cause the cooling tower expansion tank to leak during operation or affect the cooling water system from entering the air, which may cause alarms or shutdowns, posing a significant threat to the safety of railway locomotive operation.

[0004] The conventional method for inspecting the upper and lower cavities of a cooling tower expansion tank involves performing a pressure test on the lower cavity after its fabrication is complete. Once the pressure test is confirmed to be successful, the upper cavity is then fabricated. Finally, a final pressure test is performed on the entire expansion tank after its completion. This conventional method for detecting internal leaks in cooling tower expansion tanks is complex, inefficient, and cannot perform secondary inspections on the completed expansion tank. Summary of the Invention

[0005] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention proposes a method for detecting internal leakage in the expansion tank of a cooling tower and a cooling tower expansion tank, so as to overcome the shortcomings of the existing methods for detecting internal leakage in the expansion tank of a cooling tower, such as complexity, low efficiency, and inability to perform secondary testing on the completed cooling tower expansion tank.

[0006] In view of this, on the one hand, a method for detecting internal leakage in the expansion tank of a cooling tower according to the present invention includes the following steps: Step 1: Fill the expansion tank of the cooling tower with liquid; After the pressure in the upper chamber of the expansion tank is equal to the atmospheric pressure, liquid is injected into the lower chamber of the expansion tank. Step 2: Depressurize the expansion tank of the cooling tower; The expansion tank of the cooling tower is sealed; the upper chamber of the expansion tank is pressurized according to a preset pressure value, and the pressurization operation is stopped after the preset pressure value is reached; the liquid in the lower chamber of the expansion tank enters the upper chamber of the expansion tank through the water pipe. Step 3: Pressure maintenance of the cooling tower expansion tank; The expansion tank of the cooling tower is pressurized within a preset time period; Step 4: Determine if there is a leak in the expansion tank of the cooling tower; After the preset time period, if the pressure in the upper cavity of the expansion tank after pressure holding is equal to the preset pressure value, the liquid height in the upper cavity of the expansion tank after pressure holding is equal to the liquid height in the upper cavity of the expansion tank before pressure holding, and the liquid height in the lower cavity of the expansion tank after pressure holding is equal to the liquid height in the lower cavity of the expansion tank before pressure holding, then there is no internal leakage inside the cooling tower expansion tank.

[0007] This invention provides a method for detecting internal leakage in cooling tower expansion tanks, which has at least the following technical advantages: After the cooling tower expansion tank is manufactured, this method performs internal leakage detection on the upper and lower cavities of the expansion tank. Through four steps—liquid injection, pressure extraction, pressure holding, and detection judgment—this method quickly determines the internal leakage status of the tested cooling tower expansion tank based on preset pressure values. Compared to the limitations and complexity of conventional cooling tower expansion tank internal leakage detection methods, this method has higher versatility, saves manpower and testing time, improves product testing efficiency and accuracy, and increases the operational reliability and safety of railway locomotive equipment components.

[0008] According to some embodiments of the present invention, step two further includes: The vacuum pressure gauge, the pressure pumping device, and the internal leakage detection system are connected sequentially to the upper cavity of the expansion tank.

[0009] According to some embodiments of the present invention, the method for detecting internal leakage in the cooling tower expansion tank further includes step five: outputting a detection report; The internal leakage detection system performs data acquisition and processing, standardizes and enters detection report content, and stores and outputs internal leakage conclusions.

[0010] According to some embodiments of the present invention, in step three, the pressure value in the upper cavity of the expansion tank is displayed in real time by the vacuum pressure gauge, and the testing personnel monitor and record the pressure value in the upper cavity of the expansion tank in real time by using the vacuum pressure gauge.

[0011] According to some embodiments of the present invention, in step one, the pressure relief valve on the expansion tank of the cooling tower is manually removed so that the pressure value in the lower cavity of the expansion tank is consistent with the atmospheric pressure value. The quick-connect female connector of the inlet is connected to the quick-connect female connector of the inlet of the upper cavity of the expansion tank so that the pressure value in the upper cavity of the expansion tank is consistent with the atmospheric pressure value. Then, liquid is manually injected into the lower cavity of the expansion tank.

[0012] According to some embodiments of the present invention, in step two, the vacuum pressure gauge, the pressure pumping device, and the internal leakage monitoring system are sequentially connected to the quick-connect nut of the inlet. The pressure pumping device is activated through the internal leakage monitoring system to pump pressure into the upper cavity of the expansion tank according to a preset pressure value.

[0013] According to some embodiments of the present invention, in step four, conversely, if the pressure in the upper cavity of the expansion tank after pressure holding is less than the preset pressure value, the liquid height in the upper cavity of the expansion tank after pressure holding is less than the liquid height in the upper cavity of the expansion tank before pressure holding, or the liquid height in the lower cavity of the expansion tank after pressure holding is greater than the liquid height in the lower cavity of the expansion tank before pressure holding, then there is an internal leakage in the cooling tower expansion tank.

[0014] According to some embodiments of the present invention, the method for detecting leakage in the expansion tank of the cooling tower further includes step six: the liquid in the expansion tank of the cooling tower is discharged; The liquid in the upper and lower chambers of the expansion tank is discharged from the cooling tower expansion tank through the quick-connect fitting and the outlet pipe.

[0015] On the other hand, the present invention provides a cooling tower expansion tank internal leakage detection device, used in the aforementioned cooling tower expansion tank internal leakage detection method, comprising: A cooling tower expansion tank includes a lower expansion tank chamber and an upper expansion tank chamber positioned above the lower expansion tank chamber. A partition is provided between the lower and upper expansion tank chambers, and the lower and upper expansion tank chambers are connected by a vertically placed water pipe. The pressure relief valve is located on the lower cavity of the expansion tank; The quick-connector for the water inlet is located on the upper cavity of the expansion tank.

[0016] According to some embodiments of the present invention, a shaped anti-surge plate is installed horizontally in the lower cavity of the expansion tank; a liquid level switch is installed vertically in the lower cavity of the expansion tank; and a liquid level indicator is installed on the cavity wall of the lower cavity of the expansion tank.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this drawing or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this drawing. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a method for detecting internal leakage in the expansion tank of a cooling tower according to the present invention; Figure 2 This is a schematic diagram of the overall structure of a cooling tower expansion tank according to the present invention; Figure 3 This is a schematic diagram of the operation of a cooling tower expansion tank according to the present invention; Figure 4 This is a schematic diagram of step one, liquid injection into the expansion tank of a cooling tower, in a method for detecting internal leakage in the expansion tank of a cooling tower according to the present invention. Figure 5 This is a schematic diagram of step two, the pressure evacuation of the cooling tower expansion tank, in a method for detecting internal leakage in the expansion tank of a cooling tower according to the present invention. Figure 6 This is a schematic diagram of step three, pressure holding of the expansion tank, in a method for detecting internal leakage in the expansion tank of a cooling tower according to the present invention.

[0020] Explanation of icon numbers: 100. Cooling tower expansion tank; 101. Upper chamber of expansion tank; 1011. Pressure relief valve; 1012. Baffle plate; 102. Lower chamber of expansion tank; 1021. Quick-connect inlet connector; 1022. Cooling water cooling system; 1023. Vacuum pressure gauge; 1024. Pressure extraction device; 1025. Internal leakage detection system; 103. Baffle plate; 200. Water pipe; 201. Liquid level switch; 300. Water outlet pipe; 301. Water outlet quick connector; 400. Liquid level indicator.

[0021] The purpose, features, and advantages of this accompanying drawing will be further explained in conjunction with the embodiments and with reference to the accompanying drawing. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments provided by this invention without inventive effort are within the scope of protection of this invention.

[0023] Obviously, the accompanying drawings described below are merely some examples or embodiments of the present invention. Those skilled in the art can apply the present invention to other similar scenarios based on these drawings without any inventive effort. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this invention, modifications to design, manufacturing, or production based on the technical content disclosed in this invention are merely conventional technical means and should not be construed as insufficient disclosure of the present invention.

[0024] However, there may be instances where unnecessary detailed descriptions are omitted. For example, detailed descriptions of well-known matters or repetitive descriptions of essentially the same structures may be omitted. This is to avoid making the following description unnecessarily lengthy and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the invention and are not intended to limit the subject matter of the claims.

[0025] On the one hand, see Figures 1 to 6 As shown, a method for detecting internal leakage in a cooling tower expansion tank according to the present invention includes the following steps: Step 1: Fill the expansion tank of the cooling tower with 100ml of liquid; After the pressure value in the upper chamber 101 of the expansion tank is consistent with the atmospheric pressure value, liquid is injected into the lower chamber 102 of the expansion tank. Step 2: Depressurize the expansion tank of the cooling tower by 100%. The upper chamber 101 of the expansion tank is pressurized according to the preset pressure value. The pressurization operation is stopped after the preset pressure value is reached. The liquid in the lower chamber 102 of the expansion tank enters the upper chamber 101 of the expansion tank through the water pipe 200. Step 3: Pressurize the expansion tank of the cooling tower to 100°C; The expansion tank 100 of the cooling tower is pressurized within a preset time period; Step 4: Determine if there is an internal leak in the cooling tower expansion tank (100mm). If, after a preset time period, the pressure in the upper chamber 101 of the expansion tank after pressure holding is equal to the preset pressure value, the liquid height in the upper chamber 101 of the expansion tank after pressure holding is equal to the liquid height in the upper chamber 101 of the expansion tank before pressure holding, and the liquid height in the lower chamber 102 of the expansion tank after pressure holding is equal to the liquid height in the lower chamber 102 of the expansion tank before pressure holding, then there is no internal leakage inside the cooling tower expansion tank 100.

[0026] In this embodiment, see Figure 2 and Figure 3As shown, the main structures of the expansion tank 100 of this cooling tower are the upper chamber 101 and the lower chamber 102, which together form the internal cavity of the expansion tank. During operation, the expansion tank 100 is connected to the cooling water cooling system 1022 through the quick-connect female inlet, ensuring that the upper chamber 101 is filled with cooling medium during operation, while the lower chamber 102 is filled with cooling medium at the working level indicated by the liquid level display. The lower chamber 102 contains a portion of empty space to balance changes in the volume of the cooling medium. The specific steps for detecting internal leakage in the expansion tank are as follows: See Figure 4 As shown, Step 1: Fill the expansion tank 100 of the cooling tower with liquid; Before testing, ensure all connections of the cooling tower expansion tank 100 are securely installed and without looseness to prepare for pressure balancing. Open the upper chamber 101 of the expansion tank to bring the pressure inside to atmospheric pressure; at this point, the pressure in the upper chamber 101 is P. Once the pressure stabilizes and reaches standard atmospheric pressure, inject a liquid of the same properties as during actual operation, such as cooling water, into the lower chamber 102 of the expansion tank through a dedicated injection pipe. During injection, observe the liquid level indicator 400, ensuring the liquid is injected slowly to avoid excessive air bubbles affecting subsequent testing. Stop injection when the liquid level reaches the preset mark; at this point, the liquid level in the lower chamber 102 of the expansion tank is H. See Figure 5 As shown, step two: depressurize the expansion tank of the cooling tower by 100%. The expansion tank 100 of the cooling tower is pressurized: The upper chamber 101 of the expansion tank is pressurized to a preset pressure value. Pressurization stops once the preset pressure value is reached. The preset pressure value is P1, meaning the pressure in the upper chamber 101 after pressurization is P1, and the pressure in the lower chamber 102 is P. Due to the pressure decrease in the upper chamber 101, under the pressure difference, liquid in the lower chamber 102 enters the upper chamber 101 through the water pipe 200. After the pressure stabilizes, the liquid level in the lower chamber 102 becomes H1, and correspondingly, the liquid level in the upper chamber 101 becomes h1. At this point, P - P1 = ρgh1, where ρ is the density of the liquid, and g is the acceleration due to gravity.

[0027] See Figure 6 As shown, step three: pressurize the cooling tower expansion tank to 100°C. After the pressure reaches the preset pressure value P1, the pressure holding stage begins. After a preset time period T (set according to the actual detection accuracy requirements, generally T is 15min-40min), the pressure value in the upper chamber 101 of the expansion tank becomes P2, the pressure value in the lower chamber 102 of the expansion tank is P, the liquid level in the lower chamber 102 of the expansion tank becomes H2, and the liquid level in the upper chamber 101 of the expansion tank becomes h2. At this time, P-P2=ρgh2, where: ρ is the density of the liquid, and g is the acceleration due to gravity.

[0028] Step 4: Determine if there is an internal leak in the cooling tower expansion tank. After a preset time period T, analysis and judgment are performed based on various data points: First, a pressure comparison is performed: if the pressure value P2 in the upper chamber 101 of the expansion tank after pressure holding is equal to the preset pressure value P1, it means that the pressure value in the upper chamber 101 of the expansion tank did not change due to internal leakage during the pressure holding period. Secondly, a liquid level comparison is performed: when the liquid level height h2 in the upper chamber 101 of the expansion tank after pressure holding is equal to the liquid level height h1 in the upper chamber 101 of the expansion tank before pressure holding, and the liquid level height H2 in the lower chamber 102 of the expansion tank after pressure holding is equal to the liquid level height H1 in the lower chamber 102 of the expansion tank before pressure holding, it indicates that there is no abnormal flow of liquid between the upper chamber 101 and the lower chamber 102 of the expansion tank during the pressure holding stage, that is, there is no internal leakage inside the cooling tower expansion tank 100.

[0029] In this embodiment, after the cooling tower expansion tank 100 is manufactured, this detection method performs internal leakage detection on the upper and lower cavities of the cooling tower expansion tank 100. This detection method quickly determines the internal leakage status of the internal cavities (upper and lower cavities) of the tested cooling tower expansion tank 100 based on preset pressure values ​​through four steps: liquid injection, pressure extraction, pressure holding, and detection judgment. Compared to the limitations and complexity of conventional cooling tower expansion tank internal leakage detection methods, this method has higher versatility, saves manpower and testing time, improves product testing efficiency and accuracy, and increases the operational reliability and safety of railway locomotive equipment components.

[0030] In some specific embodiments of the present invention, step two further includes: The vacuum pressure gauge 1023, the pressure extraction device 1024, and the internal leakage detection system 1025 are sequentially connected to the upper chamber 101 of the expansion tank to extract pressure from the upper chamber 101 of the expansion tank.

[0031] In this embodiment, firstly, the air inlet of the vacuum pressure gauge 1023 is connected to the detection interface reserved in the upper cavity 101 of the expansion tank through a pressure-resistant rubber tube with an inner diameter of 8mm, and the connection is secured with a double compression fitting. Secondly, the air outlet of the pressure extraction device 1024 is connected to the air outlet of the vacuum pressure gauge 1023 through a metal bellows pipe to ensure that the pipeline is free of bends and leaks. Finally, the pressure sensor probe of the internal leakage detection system 1025 is connected to the pipeline between the vacuum pressure gauge 1023 and the pressure extraction device 1024, and a T-connector is used to acquire the signal.

[0032] The vacuum pressure gauge 1023 is used to detect the pressure value of the upper chamber 101 of the expansion tank; the pressure pumping device 1024 is used to pump pressure into the upper chamber 101 of the expansion tank; and the internal leakage detection system 1025 is used to automatically record the detection data.

[0033] See some specific embodiments of the present invention. Figure 1 As shown, the method for detecting internal leakage in the expansion tank of the cooling tower also includes step five: outputting the test report; the internal leakage detection system 1025 collects and processes data for the internal leakage detection of the expansion tank 100 of the cooling tower, standardizes and enters the test report content, and stores and outputs the internal leakage conclusions.

[0034] In this embodiment, firstly, data acquisition and processing are performed: the internal leakage detection system 1025 automatically records the system's detection start time, end time, pressure extraction start time, pressure extraction end time, pressure holding stage start time, and pressure holding stage end time through a high-precision clock module. The time accuracy is accurate to the second level, ensuring that the detection process timeline is complete and traceable.

[0035] The internal leakage detection system 1025 collects the pressure values ​​in the upper chamber 101 of the expansion tank before and after the pressure holding period. Combined with the internal leakage judgment logic in step four, it automatically calculates the pressure change difference. If the pressure change value exceeds the set threshold, for example, the set threshold is ±0.5 kPa, the system automatically marks the detection data as abnormal.

[0036] Based on the detection results of changes in pressure values ​​and comparisons of liquid level heights, the internal leak detection system 1025 automatically generates a detection conclusion of "no internal leak" or "internal leak present" according to a preset judgment algorithm. If the judgment is "internal leak present," the internal leak detection system 1025 simultaneously records the preliminary analysis results of the suspected leak location.

[0037] Secondly, the content of the test report is standardized and entered. Testing personnel must manually enter the product number (using a unique coding rule, including equipment model and production batch information), the name and employee number of the testing personnel, and the testing date into the internal leakage detection system 1025 interface. The internal leakage detection system 1025 automatically verifies the input format to ensure the completeness and accuracy of the information. The test report is then generated using a standardized template, including a cover (project name, report number, and testing unit), table of contents, test overview, test process record (time axis and pressure change curve), test conclusion, and attachments (original data tables and equipment calibration certificate). The pressure change curve is presented as a dynamic chart, supporting interactive operations such as zooming in and viewing data points.

[0038] Next, the internal leakage detection system stores and outputs the results. The 1025 internal leakage detection system encrypts and stores the original test data and report files on a local server, while automatically backing them up to a cloud storage platform, using the AES-256 encryption algorithm to ensure data security. The stored data is retained for at least 5 years and supports quick retrieval by product number, test date, and other criteria. The 1025 internal leakage detection system supports multiple report output formats. Testing personnel can choose to print a single report or generate a batch summary table of test reports according to their needs. Output reports are automatically stamped with electronic signatures and anti-counterfeiting watermarks to ensure the legal validity and authenticity of the reports. Through this comprehensive test report output process, standardized management of internal leakage detection data and intuitive presentation of test results are achieved, providing strong support for equipment maintenance and quality traceability.

[0039] In some specific embodiments of the present invention, in step three, the pressure value inside the upper chamber 101 of the expansion tank is displayed in real time by a vacuum pressure gauge 1023, and the testing personnel monitor and record the pressure value of the upper chamber 101 of the expansion tank in real time by using the vacuum pressure gauge 1023.

[0040] In this embodiment, the testing personnel need to read the pressure value displayed by the vacuum pressure gauge 1023 every 30 seconds. During the initial pressure holding phase (first 5 minutes) and the near-end phase (last 5 minutes), the monitoring frequency is increased to once every 10 seconds to ensure timely capture of pressure change trends. Two testing personnel are assigned to simultaneously read the pressure values, comparing the recorded data every 5 minutes. If a deviation of ±0.1 kPa or more occurs, the vacuum pressure gauge 1023 must be immediately reread and calibrated. When the pressure fluctuation exceeds ±0.3 kPa / min, the internal leakage detection system automatically marks the data for that period as abnormal and triggers an audible and visual alarm. The testing personnel must note the time of the abnormality, the fluctuation amplitude, and the possible causes in the record sheet. If the pressure decreases at a rate not exceeding 0.5 kPa / h during the pressure holding period, the testing personnel must check the sealing of the check valve of the pressure extraction device 1024, close all valves, eliminate the possibility of external leakage, and then continue pressure holding monitoring.

[0041] In some specific embodiments of the present invention, in step one, manually remove the pressure relief valve 1011 on the expansion water tank 100 of the cooling tower to make the pressure value in the lower chamber 102 of the expansion water tank consistent with the atmospheric pressure value. Connect the quick female joint of the water inlet to the quick joint 1021 of the water inlet of the upper chamber 101 of the expansion water tank. After the pressure value in the upper chamber 101 of the expansion water tank is consistent with the atmospheric pressure value, manually inject liquid into the lower chamber 102 of the expansion water tank.

[0042] In this embodiment, first, before performing the operation, use an infrared thermometer to detect the surface temperature of the expansion water tank to ensure that its temperature is at room temperature (20°C ± 5°C) to prevent the risk of scalding caused by high temperature. At the same time, through visual inspection and measurement with a multimeter, confirm that there are no obvious deformations or cracks in each component of the expansion water tank, and there is no short circuit or leakage in the electrical connection part. Prepare a special explosion-proof wrench for removing the pressure relief valve 1011, and its specification should match the nut of the pressure relief valve 1011; equip a high-precision electronic scale (accuracy ± 0.1 kg) for measuring the weight of the injected liquid; prepare a sufficient amount of coolant with the same actual operating conditions, and check the liquid quality of the coolant to ensure that there are no abnormal conditions such as turbidity or precipitation.

[0043] Second, wear cut-resistant gloves and goggles, and use the explosion-proof wrench to slowly loosen the nut of the pressure relief valve 1011 in the counterclockwise direction. Gradually unscrew the nut in 3 to 5 times, and the loosening amplitude each time does not exceed 1 / 4 turn to avoid injury caused by the ejection of components due to sudden pressure reduction. After removal, properly store the pressure relief valve 1011 and the sealing gasket to prevent loss or damage. After the pressure relief is completed, wait for 5 min - 10 min to fully release the pressure in the lower chamber 102 of the expansion water tank. Use a portable pressure detector to measure the pressure at different positions (at least 3 detection points) in the lower chamber 102 of the expansion water tank. When the pressure values at all detection points are stable within the range of the atmospheric pressure value (101.3 kPa ± 0.5 kPa), it is regarded as the completion of pressure balance.

[0044] Third, dock the quick female joint of the water inlet with the quick joint 1021 of the water inlet of the upper chamber 101 of the expansion water tank. When docking, ensure that the sealing rings of the two joints are completely aligned, and slowly push the female joint until a "click" locking sound is heard, indicating that the joint is correctly connected. Use a special joint airtightness detection tool to detect the airtightness of the connection, set the detection pressure to 0.2 MPa, and keep the pressure for 3 min. If the pressure value drops no more than 0.01 MPa, it is regarded as qualified. After the connection is completed, open the water inlet valve to allow a small amount of air to enter the upper chamber 101 of the expansion water tank. Use the pressure detector to measure the pressure in the upper chamber again. After the pressure is stable at the atmospheric pressure value, close the water inlet valve to ensure that the pressure value in the upper chamber 101 of the expansion water tank is consistent with the atmospheric pressure.

[0045] Finally, manually inject liquid into the lower chamber 102 of the expansion tank, controlling the injection rate to not exceed 5L / min to avoid generating too many air bubbles. Monitor the injected liquid in real time, and stop injection when the volume of the lower chamber 102 of the expansion tank reaches 1 / 3 to 1 / 4.

[0046] In some specific embodiments of the present invention, in step two, the vacuum pressure gauge 1023, the pressure extraction device 1024, and the internal leakage monitoring system are sequentially connected to the quick-connect nut of the water inlet. The pressure extraction device 1024 is started through the internal leakage monitoring system to perform pressure extraction operation on the upper chamber 101 of the expansion tank according to the preset pressure value.

[0047] In this embodiment, firstly, the connecting pipe nut of the vacuum pressure gauge 1023 is screwed into the quick-connect nut connector at the inlet, and tightened with a torque wrench to a torque of 15 N·m-20 N·m to ensure a secure connection. Next, the pipe of the pressure-drawing device 1024 is connected to the quick-connect nut connector at the other end of the vacuum pressure gauge 1023, and tightened again with a torque wrench. Finally, the data acquisition line of the internal leakage monitoring system is connected to the control terminal of the pressure-drawing device 1024 and the data output terminal of the vacuum pressure gauge 1023, using an aviation plug for a quick and stable electrical connection. After connection, each connection point should be checked for tightness, and a gentle pull should be performed to confirm there is no looseness. The quick-connect nut connector allows for quick connection and disassembly of the vacuum pressure gauge 1023, pressure-drawing device 1024, and internal leakage monitoring system without the need for complex tools, significantly shortening equipment installation time compared to traditional threaded connections. In batch testing operations, this significantly improves overall testing efficiency and reduces the problem of extended testing cycles caused by excessive equipment connection time. The quick-release nut connector is designed with a special sealing structure, which, together with a high-temperature and high-pressure resistant rubber sealing ring, can form a good sealing effect during the pumping process. This effectively prevents outside air from entering the upper chamber 101 of the expansion tank, avoiding problems such as inaccurate pumping and deviation in test results due to gas leakage, and ensuring the reliability of internal leakage test data.

[0048] In some specific embodiments of the present invention, in step four, conversely, if the pressure in the upper chamber 101 of the expansion tank after pressure holding is less than the preset pressure value, the liquid height in the upper chamber 101 of the expansion tank after pressure holding is less than the liquid height in the upper chamber 101 of the expansion tank before pressure holding, or the liquid height in the lower chamber 102 of the expansion tank after pressure holding is greater than the liquid height in the lower chamber 102 of the expansion tank before pressure holding, then there is an internal leakage inside the cooling tower expansion tank 100.

[0049] In this embodiment, a comprehensive judgment is made based on both pressure and liquid level, considering specific numerical differences and rates of change. Allowable error ranges and thresholds are also set to avoid misjudgments caused by minor fluctuations. Furthermore, considering the correlation between pressure and liquid level changes allows for more accurate identification of internal leaks, reducing the probability of missed or false diagnoses. First, easily leaking points are visually inspected. Then, a segmented sealing detection method is used to determine the leaking section. This is supplemented by ultrasonic leak detectors or dye-based detection methods, achieving a systematic process from initial investigation to precise location, significantly shortening leak location time and improving maintenance efficiency. Each step is closely linked and progressively advanced, from data comparison and analysis to determine internal leaks, to locating leak points, recording reports, and then to re-inspection and verification, forming a complete detection closed loop. This makes the entire internal leak judgment process logically clear, scientifically rigorous, and enhances the professionalism and reliability of the detection technology.

[0050] In some specific embodiments of the present invention, the method for detecting internal leakage in the expansion tank of the cooling tower further includes step six: liquid discharge from the expansion tank 100 of the cooling tower; the liquid in the upper chamber 101 and the lower chamber 102 of the expansion tank is discharged from the expansion tank 100 of the cooling tower through the quick connector 301 and the outlet pipe 300.

[0051] In this embodiment, before operation, it is necessary to confirm that the cooling tower expansion tank 100 and related equipment have stopped operating, and close all valves connecting the cooling tower expansion tank 100 to external systems to avoid backflow or other system interference during liquid discharge. Simultaneously, prepare a suitable collection container, ensuring its volume is greater than the total capacity of the upper chamber 101 and lower chamber 102 of the expansion tank, and place it in a location convenient for liquid discharge, taking precautions against leakage or contamination. During the discharge operation, tightly connect the outlet pipe 300 of the cooling tower expansion tank 100 to the collection container using the quick-connect fitting 301. Slowly open the expansion tank drain valve, using gravity and atmospheric pressure to allow the liquid in the upper chamber 101 and lower chamber 102 of the expansion tank to flow into the collection container through the outlet pipe 300 until all the liquid in the upper chamber 101 and lower chamber 102 of the expansion tank is completely discharged. After discharge, close the expansion tank drain valve. During this process, it is necessary to closely observe the drainage speed and liquid status. If the drainage is found to be abnormally slow or there are impurities or foreign objects in the liquid, the drainage should be stopped and the drain outlet and pipes should be checked for blockage.

[0052] On the other hand, see Figure 2 As shown, the present invention provides a cooling tower expansion tank 100 internal leakage detection device for the aforementioned cooling tower expansion tank internal leakage detection method, comprising a cooling tower expansion tank 100, a pressure relief valve 1011, and an inlet quick connector 1021. Wherein, The cooling tower expansion tank 100 includes a lower expansion tank chamber 102 and an upper expansion tank chamber 101 located above the lower expansion tank chamber 102. A partition 103 is provided between the lower expansion tank chamber 102 and the upper expansion tank chamber 101, and the lower expansion tank chamber 102 and the upper expansion tank chamber 101 are connected by a vertically placed water pipe 200. A pressure relief valve 1011 is provided on the lower expansion tank chamber 102, and a quick-connect water inlet 1021 is provided on the upper expansion tank chamber 101.

[0053] In this embodiment, the cooling tower expansion tank 100 includes an upper expansion tank chamber 101 and a lower expansion tank chamber 102. The upper expansion tank chamber 101 is arranged above the lower expansion tank chamber 102. Specifically, both the upper expansion tank chamber 101 and the lower expansion tank chamber 102 are cuboid structures, with the cross-sectional area of ​​the lower expansion tank chamber 102 being larger than that of the upper expansion tank chamber 101. The upper expansion tank chamber 101 and the lower expansion tank chamber 102 are in contact and separated by a partition 103, making them independent spaces. The upper expansion tank chamber 101 and the lower expansion tank chamber 102 are connected by a vertically placed water pipe 200, allowing water in the lower expansion tank chamber 102 to pass through the pipe. Water pipe 200 flows into the upper chamber 101 of the expansion tank. Specifically, the connecting water pipe 200 is welded inside the cooling tower expansion tank 100. One end of the pipe is located on the inner wall of the top of the expansion tank 100, and an external groove is provided on the inner wall of the top of the expansion tank 100 to allow water in the lower chamber 102 of the expansion tank to flow smoothly from the connecting water pipe 200 into the upper chamber 101. The other end is located on the inner wall of the bottom of the expansion tank 100, and an external groove is provided on the inner wall of the bottom of the expansion tank 100 to allow water in the lower chamber 102 of the expansion tank to flow smoothly into the connecting water pipe 200. A pressure relief valve 1011 is installed on the upper surface of the lower chamber 102 of the expansion tank to relieve pressure in the lower chamber 102, so that the pressure value inside the lower chamber 102 of the expansion tank is consistent with atmospheric pressure. The upper chamber 101 of the expansion tank has a quick-connect inlet connector 1021 on its side for connecting the vacuum pressure gauge 1023, the pumping device 1024, and the internal leak detection system 1025. The vacuum pressure gauge 1023 is a digital vacuum pressure gauge with a range covering 0 to -101.3 kPa and an accuracy class of at least 1.6, ensuring a pressure reading resolution of 0.1 kPa. The vacuum pressure gauge 1023 must have data storage and export functions for easy traceability of subsequent test data. The pumping device 1024 uses an electric rotary vane vacuum pump with a pumping rate of at least 2 L / s and an ultimate vacuum of -100 kPa. It is equipped with a pressure regulating valve and a check valve to achieve precise control of the pumping rate and pressure. The internal leak detection system 1025 uses a high-precision pressure sensor and data acquisition module integrated system with a sensor response time of less than 0.5 s and a data acquisition frequency of at least 1 time / s. The internal leak detection system 1025 supports real-time pressure curve plotting and automatic alarm functions for abnormal data.

[0054] In some specific embodiments of the present invention, an irregularly shaped anti-surge plate 1012 is installed horizontally in the lower cavity 102 of the expansion tank; a liquid level switch 201 is installed vertically in the lower cavity 102 of the expansion tank; and a liquid level display 400 is installed on the cavity wall of the lower cavity 102 of the expansion tank.

[0055] In this embodiment, a shaped anti-surge plate 1012 is horizontally installed inside the lower cavity 102 of the expansion tank to prevent excessive fluctuations in the liquid level during testing, which would hinder observation. A level switch 201 is vertically installed inside the lower cavity 102 of the expansion tank to detect changes in the liquid level. A level indicator 400 is provided on the side wall of the lower cavity 102 of the expansion tank to observe and record the liquid level height.

[0056] In some specific embodiments of the present invention, a water outlet pipe 300 is provided in the expansion tank 100 of the cooling tower. One end of the water outlet pipe 300 is located at the bottom of the upper cavity 101 of the expansion tank, and the other end of the water outlet pipe 300 is located at the bottom of the lower cavity 102 of the expansion tank and penetrates the lower cavity 102 of the expansion tank. A quick-connect fitting 301 for the water outlet and a drain valve for the expansion tank are provided at the end.

[0057] In this embodiment, the outlet pipe 300 is used to drain the liquid inside the upper chamber 101 and lower chamber 102 of the expansion tank, and the expansion tank drain valve is used to control the outflow of liquid from the outlet pipe 300. The quick-connect fitting 301 is used to connect to a collection container.

[0058] It should be noted that the present invention is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments that have the same structure and perform the same effects as the technical concept within the scope of the present invention are included within the scope of the present invention. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of the present invention, are also included within the scope of the present invention.

Claims

1. A method for detecting internal leakage in the expansion tank of a cooling tower, characterized in that, Includes the following steps: Step 1: Fill the expansion tank of the cooling tower with liquid; After the pressure in the upper chamber of the expansion tank is equal to the atmospheric pressure, liquid is injected into the lower chamber of the expansion tank. Step 2: Depressurize the expansion tank of the cooling tower; The expansion tank of the cooling tower is sealed; the upper chamber of the expansion tank is pressurized according to a preset pressure value, and the pressurization operation is stopped after the preset pressure value is reached; the liquid in the lower chamber of the expansion tank enters the upper chamber of the expansion tank through the water pipe. Step 3: Pressure maintenance of the cooling tower expansion tank; The expansion tank of the cooling tower is pressurized within a preset time period; Step 4: Determine if there is a leak in the expansion tank of the cooling tower; After the preset time period, if the pressure in the upper cavity of the expansion tank after pressure holding is equal to the preset pressure value, the liquid height in the upper cavity of the expansion tank after pressure holding is equal to the liquid height in the upper cavity of the expansion tank before pressure holding, and the liquid height in the lower cavity of the expansion tank after pressure holding is equal to the liquid height in the lower cavity of the expansion tank before pressure holding, then there is no internal leakage inside the cooling tower expansion tank. In step four, if the pressure in the upper cavity of the expansion tank after pressure holding is less than the preset pressure value, the liquid height in the upper cavity of the expansion tank after pressure holding is less than the liquid height in the upper cavity of the expansion tank before pressure holding, or the liquid height in the lower cavity of the expansion tank after pressure holding is greater than the liquid height in the lower cavity of the expansion tank before pressure holding, then there is an internal leakage in the cooling tower expansion tank.

2. The method for detecting internal leakage in a cooling tower expansion tank according to claim 1, characterized in that, Step two also includes: The vacuum pressure gauge, the pressure pumping device, and the internal leakage detection system are connected sequentially to the upper cavity of the expansion tank.

3. The method for detecting internal leakage in a cooling tower expansion tank according to claim 2, characterized in that, It also includes step five: outputting the test report; The internal leakage detection system performs data acquisition and processing, standardizes and enters detection report content, and stores and outputs internal leakage conclusions.

4. The method for detecting internal leakage in a cooling tower expansion tank according to claim 2, characterized in that, In step three, the pressure value inside the upper chamber of the expansion tank is displayed in real time by the vacuum pressure gauge, and the testing personnel monitor and record the pressure value inside the upper chamber of the expansion tank in real time by using the vacuum pressure gauge.

5. The method for detecting internal leakage in a cooling tower expansion tank according to claim 2, characterized in that, In step one, the pressure relief valve on the expansion tank of the cooling tower is manually removed so that the pressure value in the lower chamber of the expansion tank is consistent with the atmospheric pressure value. The quick-connect nut connector of the inlet is connected to the quick-connect connector of the inlet of the upper chamber of the expansion tank so that the pressure value in the upper chamber of the expansion tank is consistent with the atmospheric pressure value. Then, liquid is manually injected into the lower chamber of the expansion tank.

6. The method for detecting internal leakage in a cooling tower expansion tank according to claim 5, characterized in that, In step two, the vacuum pressure gauge, the pressure pumping device, and the internal leakage monitoring system are connected sequentially to the quick-release nut connector at the inlet. The pressure pumping device is activated through the internal leakage monitoring system to pump pressure into the upper chamber of the expansion tank according to the preset pressure value.

7. The method for detecting internal leakage in a cooling tower expansion tank according to claim 1, characterized in that, The method for detecting internal leakage in the expansion tank of the cooling tower also includes step six: the liquid in the expansion tank of the cooling tower is discharged. The liquid in the upper and lower chambers of the expansion tank is discharged from the cooling tower expansion tank through the quick-connect fitting and the outlet pipe.

8. The method for detecting internal leakage in a cooling tower expansion tank according to claim 1, characterized in that, The cooling tower expansion tank includes a lower expansion tank chamber and an upper expansion tank chamber located above the lower expansion tank chamber. A partition is provided between the lower chamber and the upper chamber of the expansion tank, and the lower chamber and the upper chamber are connected by a vertically placed water pipe; and, The pressure relief valve is located on the lower cavity of the expansion tank; The quick-connector for the water inlet is located on the upper cavity of the expansion tank.

9. A method for detecting internal leakage in a cooling tower expansion tank according to claim 8, characterized in that, A shaped baffle plate is installed horizontally inside the lower cavity of the expansion tank; a liquid level switch is installed vertically inside the lower cavity of the expansion tank; and a liquid level indicator is installed on the cavity wall of the lower cavity of the expansion tank.

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