A safety valve setting pressure checking method based on strain sensor feedback

Abstract

This invention discloses a method for verifying the set pressure of a safety valve based on strain sensor feedback, belonging to the field of safety valve inspection technology. The invention involves installing a strain sensor component between the adjusting nut and the upper clamping block of the safety valve. A data acquisition and processing module converts axial stress changes into set pressure characteristic values. By comparing real-time characteristic values ​​with historical benchmark data at a control terminal, the deviation is calculated, and an adjustment command is output. Set pressure calibration is completed through closed-loop feedback, while also supporting remote operation and automated adjustment. This invention is mainly used for offline and online verification of the set pressure of spring-loaded safety valves used in various pressure-bearing equipment. It enables quantitative feedback during the set pressure adjustment process, improving verification accuracy and operational efficiency, and reducing safety risks during on-site operations under complex conditions.

Description

Technical Field

[0001] This invention belongs to the field of safety valve inspection technology, specifically relating to the technical field of setting pressure verification for spring-loaded safety valves used in pressure equipment. Background Technology

[0002] Spring-loaded safety valves are critical safety accessories for various pressure-bearing equipment such as boilers, pressure vessels, and pressure pipelines. The accuracy of their set pressure directly determines the operational safety of the pressure-bearing equipment. Therefore, it is necessary to periodically verify the set pressure of safety valves in accordance with safety regulations. Currently, the industry commonly uses a pressure-increasing opening method for verifying the set pressure of safety valves. This involves introducing pressurized medium into the safety valve, gradually increasing the pressure until the valve opens, recording the corresponding opening pressure, and then adjusting the adjusting nut. This process is repeated multiple times to complete the calibration of the set pressure.

[0003] This type of calibration method requires repeated operations of pressurizing the medium and opening the safety valve. The judgment of deviations in the set pressure and the adjustment of the adjusting nut during the calibration process rely heavily on the operator's experience. By gradually approaching the target set pressure through trial and error, the calibration time for a single safety valve is long, resulting in low overall calibration efficiency. Furthermore, the repeated opening and closing of the safety valve accelerates the wear of the valve disc and seat sealing surfaces, adversely affecting the sealing performance and service life of the safety valve.

[0004] During the calibration process, operators need to be in close proximity to the pressure equipment to complete operations and read data. Under complex industrial conditions involving high temperature, high pressure, toxicity, flammability, and explosiveness, there are numerous safety hazards for operators, making remote operation of the calibration process difficult. Furthermore, existing calibration methods cannot obtain real-time quantitative feedback of the spring preload during adjustment, cannot establish a direct correlation between the set pressure and the spring preload, and the adjustment accuracy of the set pressure is greatly affected by human factors, resulting in poor consistency in calibration results from different operators.

[0005] The existing verification process relies heavily on manual recording of data, making it difficult to achieve electronic storage and full-process traceability of verification data, thus failing to meet the development needs of intelligent and digital management in industrial production. Furthermore, the existing verification methods can only perform periodic pressure calibration and cannot continuously monitor the spring preload of safety valves over long periods, making it difficult to promptly detect safety hazards caused by abnormal changes in spring preload. Summary of the Invention

[0006] The purpose of this invention is to provide a method for verifying the set pressure of a safety valve based on strain sensor feedback, which solves the problems of existing safety valve set pressure verification relying on manual experience, lacking quantitative feedback during the adjustment process, resulting in low verification accuracy and low operating efficiency.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for verifying the set pressure of a safety valve based on strain sensor feedback is implemented using a safety valve set pressure verification system. The system includes a safety valve body, a strain sensor component, a data acquisition and processing module, a storage module, and a comparison and control terminal. The method includes the following steps:

[0009] The strain sensor assembly is installed between the adjusting nut and the upper clamping block of the safety valve body to complete the electrical connection and self-test of each component of the system.

[0010] The safety valve body is calibrated according to standard, the standard set pressure value is recorded, the corresponding strain electrical signal is acquired using the data acquisition and processing module and converted into standard strain characteristic value, the standard set pressure value and standard strain characteristic value are bound as historical reference data and stored in the storage module.

[0011] The strain electrical signal output by the strain sensing component is acquired in real time using the data acquisition and processing module, converted into a real-time set pressure characteristic value, and transmitted to the comparison and control terminal.

[0012] By comparing and controlling the historical reference data retrieved from the storage module, the real-time set pressure characteristic value is compared with the standard strain characteristic value, the deviation value is calculated, and an adjustment command or a verification pass command is output based on the deviation value.

[0013] The adjusting nut of the safety valve body is rotated and adjusted according to the adjustment command. During the adjustment process, the strain electrical signal is collected simultaneously and the real-time set pressure characteristic value is updated until the deviation value falls within the preset allowable error range.

[0014] After confirming the stability of the real-time set pressure characteristic value by comparing with the control terminal, the verification is deemed qualified, and verification data is generated and stored.

[0015] In one possible implementation, when acquiring the strain electrical signal, the strain electrical signal is amplified, filtered, and converted from analog to digital by the data acquisition and processing module, and then converted into the real-time set pressure characteristic value or the standard strain characteristic value.

[0016] When calculating the deviation value, the deviation value is calculated by comparing it with the relative difference between the real-time set pressure characteristic value and the standard strain characteristic value by the control terminal. At the same time, the adjustment direction and estimated adjustment angle of the adjusting nut are determined according to the magnitude and direction of the deviation value.

[0017] In one possible implementation, when the adjusting nut is rotated for adjustment, the adjustment process is a real-time closed-loop feedback adjustment. The data acquisition and processing module synchronously updates the real-time set pressure characteristic value and transmits it to the comparison and control terminal. The comparison and control terminal dynamically updates the adjustment command according to the real-time deviation value until the deviation value falls within the preset allowable error range.

[0018] In one possible implementation, the system further includes a wireless communication module electrically connected to the data acquisition and processing module and the comparison and control terminal.

[0019] During the verification process, the real-time set pressure characteristic value and deviation value are transmitted to a remote comparison and control terminal via a wireless communication module. At the same time, the wireless communication module receives adjustment instructions issued by the comparison and control terminal, realizing remote operation of the verification process.

[0020] In one possible implementation, the system further includes an electric actuator module electrically connected to a comparison and control terminal and mounted on the outside of the adjusting nut of the safety valve body;

[0021] After the adjustment command is output, the electric actuator module receives the adjustment command from the comparison and control terminal and automatically drives the adjusting nut to complete the rotation adjustment. During the adjustment process, the electric actuator module monitors the rotation torque in real time to prevent damage to components.

[0022] In one possible implementation, after the verification is deemed successful, an electronic verification report is automatically generated by comparison and control terminal. The electronic verification report includes basic information of the safety valve body, historical benchmark data, data of the current verification process, and verification results. The electronic verification report and the entire process data of the current verification are stored in the storage module, and remote uploading and local printing of data are also supported.

[0023] In one possible implementation, the system further includes an alarm module electrically connected to a comparison and control terminal;

[0024] During the verification process, if there is a sudden change in the strain signal, the deviation value exceeds the preset alarm threshold, or the component communication is abnormal, the alarm module will be triggered by comparison and control terminal to issue an alarm signal, and the cause of the fault will be indicated at the same time.

[0025] In one possible implementation, after verification, the system performs self-diagnosis of the working status of each component by comparison and control terminal, organizes, backs up and maintains the historical benchmark data and verification process data in the storage module, and realizes the operation data management of the safety valve body throughout its entire life cycle.

[0026] In one possible implementation, the strain sensing component includes an elastomer and a resistive strain gauge, wherein the resistive strain gauge is attached to the stressed surface of the elastomer, and the strain electrical signal is acquired through a full-bridge circuit layout.

[0027] When installing the strain sensor assembly, place the strain sensor assembly on the outside of the valve stem of the safety valve body, so that the upper and lower surfaces of the strain sensor assembly are in close contact with the bottom end face of the adjusting nut and the top end face of the upper clamping block, respectively, to complete the non-destructive installation.

[0028] Compared with the prior art, the advantages of this invention are as follows:

[0029] Compared to existing pressure-boosting calibration techniques, this invention, by installing a strain sensor between the adjusting nut and the upper clamping block on the safety valve body, can collect real-time data on changes in axial stress during adjustment. The data acquisition and processing module converts these mechanical changes into characteristic signals corresponding to the set pressure, establishing a correlation between the strain signal and the set pressure. Existing calibration techniques cannot obtain real-time feedback on the spring preload during adjustment, relying solely on operator experience for trial-and-error adjustments. This invention provides continuous quantitative references during adjustment, eliminating the need for repeated pressure-boosting tests to calibrate the set pressure. This shortens the calibration time for a single safety valve, improves overall calibration efficiency, reduces the impact of human factors on calibration results, and ensures good consistency of calibration results across different operating scenarios.

[0030] Existing calibration techniques require repeated pressurization of the medium and opening of the safety valve to complete the calibration of the set pressure. Frequent opening actions exacerbate the wear of the valve disc and valve seat sealing surfaces, adversely affecting the sealing performance and service life of the safety valve. The technical solution of this invention can adjust the adjusting nut through real-time strain signal feedback. During the adjustment process, there is no need to repeatedly open the safety valve. Only a single verification opening is required after calibration, reducing the number of times the safety valve is opened, lowering the wear rate of internal valve components, helping to extend the service life of the safety valve, and reducing the consumption of pressurized medium, thus reducing the material cost of calibration operations.

[0031] Existing calibration technologies require operators to be in close proximity to pressure equipment to perform adjustments and read data, posing significant safety hazards in complex industrial conditions and hindering remote operation. This invention, through a wireless communication module, enables remote transmission of calibration data and remote issuance of adjustment commands. Operators can complete the entire calibration process from areas away from the work site, eliminating the need for close contact with pressure equipment under complex conditions and reducing operational safety hazards. Simultaneously, the electric actuator module receives adjustment commands from the comparison and control terminal, automatically adjusting the rotation of the adjusting nut, further reducing manual workload and adapting to the needs of automated operations in industrial settings.

[0032] Existing calibration technologies often rely on manual recording of process data, making it difficult to achieve complete data traceability and enabling long-term continuous monitoring of the safety valve's operating status. This invention, through a storage module, can completely store historical baseline data and full-process data from each calibration of the safety valve. By comparing and controlling the data with the terminal, standardized calibration reports can be automatically generated, achieving electronic storage and traceable management of calibration data. Simultaneously, the strain gauge component can be installed and used with the safety valve long-term, continuously monitoring changes in spring preload, and promptly detecting abnormal deviations in the set pressure, providing data support for the safe and stable operation of pressure-bearing equipment. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the safety valve setting pressure verification system in an embodiment of the present invention;

[0035] Figure 2 This is a schematic diagram showing the assembly position of the strain sensing component on the safety valve in an embodiment of the present invention.

[0036] Figure 3 This is a schematic diagram of the safety valve setting pressure verification method in an embodiment of the present invention;

[0037] Figure 4 This is a schematic diagram of the structure of the annular strain sensing component in an embodiment of the present invention;

[0038] Figure 5 This is a schematic diagram of the structure of the handheld data acquisition and processing terminal in an embodiment of the present invention.

[0039] The components include: 1. valve stem; 2. adjusting nut; 3. strain sensing assembly; and 4. upper clamping block. Detailed Implementation

[0040] 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 this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0041] Example:

[0042] It should be noted that the terms "comprising" and "having" and any variations thereof in the embodiments of the present invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products, or devices.

[0043] See Figure 1 , Figure 2 and Figure 3 This invention provides a method for verifying the set pressure of a safety valve based on strain sensing feedback. The method is implemented using a safety valve set pressure verification system, which includes a safety valve body, a strain sensing component, a data acquisition and processing module, a storage module, and a comparison and control terminal. Further, the strain sensing component includes an elastic body and a resistance strain gauge. The resistance strain gauge is attached to the force-bearing surface of the elastic body, and strain electrical signals are acquired through a full-bridge circuit layout. When installing the strain sensing component, it is fitted onto the outside of the valve stem of the safety valve body, ensuring that the upper and lower surfaces of the strain sensing component are tightly fitted with the bottom end face of the adjusting nut and the top end face of the upper clamping block, respectively, completing a non-destructive installation.

[0044] Specifically, the elastomer can be a matrix structure made of high-elasticity alloy steel, and the material can be chromium-vanadium alloy steel or silicon-manganese alloy steel. The shape can be annular, cylindrical, or spherical. The resistance strain gauge can be a high-precision metal foil strain gauge, such as constantan foil strain gauge or nickel-chromium foil strain gauge. The full-bridge circuit layout can be a full-bridge circuit in which two resistance strain gauges are attached to each of the upper and lower stress surfaces of the elastomer to form a Wheatstone bridge. Non-destructive installation can be an installation method that does not require welding, drilling, cutting, or other processing of the components of the safety valve body.

[0045] The method includes the following steps:

[0046] Step 101: Install the strain sensor assembly between the adjusting nut and the upper clamping block of the safety valve body to complete the electrical connection and self-test of each component of the system.

[0047] Specifically, the safety valve body can be an industrial general spring-loaded safety valve, suitable for use in pressure-bearing equipment in industries such as petrochemical, power energy, and metallurgical manufacturing; the strain sensing component can be a sensing element containing an elastomer and a resistance strain gauge. The elastomer can be a ring-shaped, cylindrical, or spherical structure made of chromium vanadium alloy steel or silicon manganese alloy steel, and the resistance strain gauge can be a constantan foil strain gauge or a nickel-chromium foil strain gauge, which is attached to the force-bearing surface of the elastomer using a full-bridge circuit layout.

[0048] Step 102: Perform standard calibration on the safety valve body, record the standard set pressure value, use the data acquisition and processing module to acquire the corresponding strain electrical signal and convert it into standard strain characteristic value, bind the standard set pressure value and standard strain characteristic value as historical benchmark data, and store them in the storage module.

[0049] Specifically, the data acquisition and processing module can be an industrial-grade acquisition device integrating signal amplification circuits, filtering circuits, analog-to-digital conversion chips, and microprocessors, such as a handheld acquisition terminal, a wall-mounted acquisition box, or an integrated circuit board; the storage module can be an industrial-grade non-volatile storage medium, such as FLASH memory, SD card, or solid-state drive; the standard set pressure value can be the opening pressure value required by the safety valve design, such as 1.6MPa, 1.2MPa, or 3.8MPa; the standard strain characteristic value can be a voltage value or digital quantity corresponding to the standard set pressure value, such as a linearly corresponding value within the range of 0 to 5V or 0 to 10V.

[0050] When acquiring the strain electrical signal, the data acquisition and processing module sequentially amplifies, filters, and performs analog-to-digital conversion on the strain electrical signal, and then converts it into the real-time set pressure characteristic value or the standard strain characteristic value.

[0051] Specifically, amplification processing can be performed by a high-precision instrumentation amplifier to amplify the weak strain electrical signal by a factor of 100 to 1000; filtering processing can be performed by an active low-pass filter circuit to remove noise from the amplified signal, which is used to remove high-frequency noise signals caused by electromagnetic interference and equipment vibration in the industrial environment; analog-to-digital conversion processing can be performed by an analog-to-digital converter chip with a resolution of not less than 16 bits to convert the analog electrical signal into a digital signal.

[0052] Step 103: The strain electrical signal output by the strain sensing component is acquired in real time using the data acquisition and processing module, converted into a real-time set pressure characteristic value, and transmitted to the comparison and control terminal.

[0053] Step 104: By comparing and controlling the historical reference data retrieved from the storage module, the real-time set pressure characteristic value is compared with the standard strain characteristic value, the deviation value is calculated, and an adjustment command or a verification pass command is output based on the deviation value.

[0054] Specifically, the comparison and control terminal can be a field operation screen, an industrial tablet computer, or a computer terminal.

[0055] When calculating the deviation value, the deviation value is calculated by comparing the relative difference between the real-time set pressure characteristic value and the standard strain characteristic value with the control terminal. At the same time, the adjustment direction and estimated adjustment angle of the adjusting nut are determined based on the magnitude and direction of the deviation value.

[0056] Specifically, the deviation value can be the percentage of the relative deviation between the real-time set pressure characteristic value and the standard strain characteristic value; the adjustment direction can be tightening or loosening the adjusting nut; the estimated adjustment angle can be the rotation angle of the adjusting nut calculated based on the magnitude of the deviation value and the correspondence with the previous calibration, such as 135°, 72°, or 81°.

[0057] In some embodiments, the system further includes a wireless communication module electrically connected to a data acquisition and processing module and a comparison and control terminal. During the verification process, the wireless communication module transmits the real-time set pressure characteristic value and deviation value to the remote comparison and control terminal, and simultaneously receives adjustment instructions issued by the comparison and control terminal, thereby realizing remote operation of the verification process.

[0058] Specifically, the wireless communication module can be an industrial-grade wireless communication module, using 4G, 5G and LoRa dual-mode communication, with a transmission delay of no more than 1 second; the remote comparison and control terminal can be a computer terminal set up in a remote control room, which can connect to multiple field acquisition devices at the same time to realize centralized verification and management of multiple safety valves.

[0059] Step 105: Rotate the adjusting nut of the safety valve body according to the adjustment instruction. During the adjustment process, the strain electrical signal is collected simultaneously and the real-time set pressure characteristic value is updated until the deviation value falls within the preset allowable error range.

[0060] Specifically, the preset allowable error range can be ±1% to ±3%, which can be set according to the calibration standards and industrial needs.

[0061] When the adjusting nut is rotated, the adjustment process is a real-time closed-loop feedback adjustment. The data acquisition and processing module synchronously updates the real-time set pressure characteristic value and transmits it to the comparison and control terminal. The comparison and control terminal dynamically updates the adjustment command according to the real-time deviation value until the deviation value falls within the preset allowable error range.

[0062] Specifically, real-time closed-loop feedback adjustment can be a closed-loop control process in which the adjustment of the adjusting nut is synchronized with the acquisition of strain electrical signals, the updating of characteristic values, and the calculation of deviations, and the adjustment response time can not exceed 1 second.

[0063] In some embodiments, the system further includes an electric actuator module electrically connected to a comparison and control terminal and installed on the outside of the adjusting nut of the safety valve body. After outputting an adjustment command, the electric actuator module receives the adjustment command from the comparison and control terminal and automatically drives the adjusting nut to complete the rotation adjustment. During the adjustment process, the electric actuator module monitors the rotation torque in real time to prevent component damage.

[0064] Specifically, the electric actuator module can be an automated actuator integrating a stepper motor, reduction gear, clamping mechanism, and torque sensor. The rotational accuracy of the stepper motor is not less than 0.1°. The torque sensor can be a sensing component that monitors the rotational torque of the adjusting nut in real time. A torque threshold can be set to prevent excessive torque from damaging components such as the adjusting nut and valve stem.

[0065] Step 106: After confirming the stability of the real-time set pressure characteristic value by comparing with the control terminal, the verification is deemed qualified, and verification data is generated and stored.

[0066] Historical benchmark data can be the bound standard set pressure value and standard strain characteristic value, which can be used as the benchmark for subsequent verification.

[0067] After the verification is deemed successful, an electronic verification report is automatically generated by comparison and control terminal. The electronic verification report includes basic information of the safety valve body, historical benchmark data, data of the current verification process, and verification results. The electronic verification report and the entire process data of the current verification are stored in the storage module, and remote uploading and local printing of data are also supported.

[0068] Specifically, the electronic calibration report can be a standardized digital format calibration report, supporting electronic signatures and format conversion; the basic information of the safety valve body can be the equipment number, model, specifications, nominal pressure, nominal diameter, installation location, equipment to which it belongs, manufacturer, and manufacturing date; historical benchmark data can be the standard set pressure value, standard strain characteristic value, calibration time, and calibration personnel; the data of this calibration process can be the calibration time, calibration personnel, real-time set pressure characteristic value, relative deviation value, adjustment direction, adjustment angle, and number of adjustments; the calibration result can be calibration pass or fail, allowable error range, actual deviation range, and opening verification result; the storage module can be an industrial-grade non-volatile storage medium, such as FLASH memory, SD card, or solid-state drive; remote upload can be to upload data to the enterprise equipment management platform or industrial internet platform via a wireless communication module; local printing can be to output a paper version of the calibration report through on-site printing equipment.

[0069] After verification, the system performs self-diagnosis of the working status of each component by comparing and controlling the terminal, and organizes, backs up and maintains the historical benchmark data and verification process data in the storage module, so as to realize the operation data management of the safety valve body throughout its entire life cycle.

[0070] Specifically, self-diagnosis of working status can be automated detection and troubleshooting of the working status, operating parameters, and communication status of various system components; organization, backup, and maintenance can be the classification, organization, multiple copy backup, and invalid data cleanup of data in the storage module; and full lifecycle operation data management can be the unified storage, query, traceability, and statistical analysis of the entire process data of the safety valve body from initial calibration, repeated verifications, anomaly handling, maintenance, and modification.

[0071] In some embodiments, the system further includes an alarm module electrically connected to a comparison and control terminal. During the verification process, if a sudden change in the strain signal, a deviation value exceeding a preset alarm threshold, or a component communication anomaly occurs, the comparison and control terminal triggers the alarm module to issue an alarm signal, while simultaneously indicating the cause of the fault.

[0072] Specifically, the alarm module can be a combination of modules integrating audible and visual alarms and remote SMS alarms, such as including a red alarm indicator light, a buzzer, and an alarm SMS module; the preset alarm threshold can be a deviation value exceeding the allowable error range, such as ±3% or ±5%; a sudden change in strain signal can be a signal anomaly where the change in strain characteristic value per unit time exceeds the preset range; a component communication anomaly can be a communication interruption or excessive data transmission delay between the strain sensing component, the data acquisition and processing module, and the wireless communication module; the alarm signal can be an on-site audible and visual alarm signal or a remote SMS alarm signal; the cause of the fault can be an abnormal signal from the strain sensing component, a fault in the data acquisition and processing module, an interruption in wireless communication, an excessive deviation in the set pressure, or a loose adjusting nut.

[0073] Example 1

[0074] The safety valve to be calibrated in this embodiment is a spring-loaded safety valve for the steam pipeline of a catalytic cracking unit in a petrochemical enterprise. The nominal pressure of the safety valve is 1.6 MPa, the nominal diameter is DN50, and the standard set pressure is 1.6 MPa. It is installed on an aerial support for a high-temperature steam pipeline with an operating temperature of 350°C. The on-site conditions are high temperature and high altitude. Traditional online calibration methods require operators to work at close range on the aerial support, which poses a high safety risk and makes it difficult to guarantee calibration accuracy.

[0075] See Figure 4 and Figure 5 In this embodiment, a circular strain gauge component is selected. The inner diameter of the strain gauge component matches the outer diameter of the safety valve stem. The elastic body of the strain gauge component is made of chromium vanadium alloy steel, and four constantan foil resistance strain gauges are attached to the surface of the elastic body, forming a full-bridge circuit. The operator climbs onto the high-altitude support via scaffolding and places the strain gauge component directly on the contact surface between the safety valve adjusting nut and the upper clamping block. The adjusting nut is tightened to ensure a tight fit between the adjusting nut, the strain gauge component, and the upper clamping block. The entire installation process takes 8 minutes and involves no destructive processing. The strain gauge component is then connected to a handheld data acquisition and processing terminal via a high-temperature shielded wire. This handheld data acquisition and processing terminal is equipped with a 3.5-inch display screen and operation buttons. Internally, the terminal incorporates a signal amplification circuit, a filtering circuit, a 16-bit A / D converter chip, and a microprocessor. The terminal is powered by a 10000mAh lithium battery. The handheld data acquisition and processing terminal is wirelessly connected to the comparison and control terminal via Bluetooth, and the comparison and control terminal is electrically connected to the storage module. After completing the wiring connection, start the system and perform a system self-test to confirm that all modules are communicating normally, the strain sensing components are working properly, and the data acquisition and processing terminal can acquire strain signals normally. The system debugging is then complete.

[0076] Since this safety valve is the first time the strain sensing component of this invention has been installed, initial calibration is required. This embodiment employs an online standard calibration method, using a hydraulic lifting force device to perform standard calibration on the safety valve until it passes the calibration, recording the standard set pressure value P0 as 1.6 MPa. After the safety valve stabilizes at the set pressure of 1.6 MPa, the data acquisition and processing module acquires the strain electrical signal output by the strain sensing component. This strain electrical signal is processed and converted into a standard strain characteristic value V0 of 2.500V, with a range of 0V to 5V. The standard set pressure value P0 of 1.6 MPa is bound to the standard strain characteristic value V0 of 2.500V as historical reference data for the safety valve, and written to the SD card of the storage module, completing the initial calibration.

[0077] One year after initial calibration, the safety valve undergoes periodic online verification. Operators, carrying handheld data acquisition and processing terminals, ascend to an aerial support structure and connect the terminal to the strain sensor assembly. Simultaneously, the device number of the safety valve is input into the ground-based comparison and control terminal. The system automatically retrieves the corresponding historical reference data from the storage module. This historical reference data includes a standard set pressure value P0 of 1.6 MPa and a standard strain characteristic value V0 of 2.500 V. The system enters real-time acquisition mode, setting the sampling frequency to 200 Hz. The data acquisition and processing terminal acquires the strain signal output by the strain sensor assembly in real time and converts it into a real-time set pressure characteristic value Vt of 2.350 V. This real-time set pressure characteristic value is transmitted to the ground-based comparison and control terminal via Bluetooth. The comparison and control terminal calculates the relative deviation between the real-time set pressure characteristic value and the standard strain characteristic value. The relative deviation is calculated by subtracting the standard strain characteristic value from the real-time set pressure characteristic value, dividing by the standard strain characteristic value, and then multiplying by 100%, resulting in a relative deviation of -6.0%. The system's preset allowable error range is ±2%. If the absolute value of the calculated relative deviation is greater than 2% and the relative deviation is negative, it indicates that the current safety valve's set pressure is lower than the standard value, and the adjusting nut needs to be tightened. Based on the previously calibrated strain characteristic value, adding 0.1V corresponds to a 90° clockwise rotation of the adjusting nut, the system calculates an estimated adjustment angle of 135° and displays a prompt on the control terminal screen indicating a 135° clockwise rotation of the adjusting nut.

[0078] Ground operators send adjustment commands to aerial operators via walkie-talkie. The aerial operators, following the received commands, use a wrench to rotate the adjusting nut clockwise. During adjustment, a handheld data acquisition and processing terminal collects the strain signal output from the strain sensor component in real time. The real-time set pressure characteristic value gradually increases with the rotation of the adjusting nut. Real-time data is synchronously transmitted to the ground-based comparison and control terminal via Bluetooth, enabling visual monitoring of the adjustment process. When the adjusting nut is rotated 130° clockwise, the real-time set pressure characteristic value is 2.498V, and the calculated relative deviation is -0.08%, which is within the allowable error range of ±2%. The ground operators immediately notify the aerial operators to stop the adjustment and tighten the locking nut. The system continues to collect real-time data for 60 seconds, confirming that the real-time set pressure characteristic value is stable between 2.498V and 2.502V, with no signal drift or fluctuation. The comparison and control terminal determines that the safety valve has passed calibration. The system automatically generates an electronic calibration report, records all data from the calibration, writes the entire calibration process data to the storage module, and transmits the electronic calibration report to a handheld data acquisition and processing terminal via Bluetooth. Operators then print the calibration report on-site, completing the safety valve set pressure calibration. The entire calibration process took 4 minutes, with the adjustment process taking only 1 minute. No steam pressurization or safety valve opening tests were required during the calibration, significantly reducing the operator's working time at height.

[0079] The verification method described in this embodiment enables online verification of safety valves under high-temperature and high-altitude conditions, achieving a verification accuracy of -0.08%, which meets the verification requirements of relevant safety regulations. The overall verification time is 7.5 times shorter than traditional online verification, significantly reducing the time operators spend working at heights and effectively lowering the risks of falls and burns. The verification process did not involve repeated opening of the safety valve; only one verification opening was performed. The actual opening pressure during the verification opening was 1.602 MPa, with a deviation from the standard value of 0.125%, significantly reducing wear on the valve disc and seat and helping to extend the service life of the safety valve.

[0080] Example 2

[0081] The safety valve to be tested in this embodiment is a spring-loaded safety valve of a high-pressure gas pipeline of a municipal gas company. The nominal pressure of the safety valve is 1.6MPa, the nominal diameter is DN40, and the standard set pressure is 1.2MPa. It is installed in a suburban gas pressure regulating station in an open-air environment with no power supply and a risk of natural gas leakage. Traditional testing requires operators to work on-site at close range, which poses a high safety risk and is inconvenient for real-time monitoring.

[0082] This embodiment uses a cylindrical strain gauge component, which is adapted to the contact area between the safety valve adjusting nut and the upper clamping block. The elastic body of the strain gauge component is made of silicon-manganese alloy steel, and four nickel-chromium foil resistance strain gauges are attached to the surface of the elastic body. The four resistance strain gauges form a full-bridge circuit. The installer places the strain gauge component between the adjusting nut and the upper clamping block, and tightens the adjusting nut to complete the fixation. The entire installation process takes 6 minutes. The system in this embodiment is configured with a wall-mounted data acquisition and processing module. This module has a built-in signal amplification circuit, a filtering circuit, a 16-bit A / D analog-to-digital converter chip, and an STM32 microprocessor. It is also configured with a wireless communication module, a storage module, a comparison and control terminal, an alarm module, and a power supply module. The wireless communication module uses a 4G and LoRa dual-mode module, the storage module uses 128M FLASH memory, the comparison and control terminal is a computer in the remote control room, the alarm module includes a red indicator light, a buzzer, and an SMS alarm module, and the power supply module uses a 10000mAh lithium battery. The wall-mounted data acquisition and processing module is installed on a bracket near the safety valve and connected to the strain sensing component via shielded wires. The wireless communication module is integrated inside the data acquisition and processing module, and the power supply module provides power to the entire system. A computer in the remote control room is equipped with dedicated calibration software and establishes a communication connection with the on-site wireless communication module via a 4G network. After completing data transmission tests, the system is confirmed to be functioning correctly.

[0083] After the safety valve is first installed in this system, initial calibration is required. The operator disassembles the safety valve and places it on the offline calibration bench, introduces nitrogen gas into the bench, and gradually increases the pressure until the safety valve opens, recording the standard set pressure value P0 as 1.2 MPa. The data acquisition and processing module acquires the strain signal output by the strain sensor component at this time, converting the strain signal into a standard strain characteristic value V0 of 2.000V, with a range of 0V to 5V. The operator binds the standard set pressure value of 1.2 MPa and the standard strain characteristic value of 2.000V as historical reference data, stores this data in the on-site FLASH memory, and simultaneously uploads it to the computer database in the remote control room via the 4G network, completing the initial calibration.

[0084] Six months after the initial calibration, operators performed periodic online verification of the safety valve. Operators in the remote control room input the valve's equipment number into the verification software, and the system automatically retrieved the corresponding historical reference data, including a standard set pressure of 1.2 MPa and a standard strain characteristic value of 2.000 V. Operators issued real-time acquisition commands through the verification software. Upon receiving the command, the on-site system entered acquisition mode, setting the sampling frequency to 150 Hz. The data acquisition and processing module acquired the strain signal output by the strain sensor component in real time, converting the strain signal into a real-time set pressure characteristic value Vt of 2.120 V. This data was transmitted to the remote control room via a 4G network with a transmission delay of 0.8 seconds. The verification software calculated the relative deviation between the real-time set pressure characteristic value and the standard strain characteristic value. The relative deviation was calculated by subtracting the standard strain characteristic value from the real-time set pressure characteristic value, dividing by the standard strain characteristic value, and then multiplying by 100%, resulting in a final relative deviation value of 6.0%. The system's preset allowable error range is ±3%. If the calculated relative deviation value is greater than 3% in absolute terms and is positive, it indicates that the current safety valve's set pressure is higher than the standard value, requiring the adjusting nut to be loosened. Based on the previously calibrated relationship between a 0.1V decrease in strain characteristic value and a 60° counter-clockwise rotation of the adjusting nut, the system calculates an estimated adjustment angle of 72°. The verification software simultaneously displays the adjustment command as a 72° counter-clockwise rotation of the adjusting nut.

[0085] The remote operator sends adjustment instructions to the on-site construction personnel via calibration software. The construction personnel then use a wrench to rotate the adjusting nut counter-clockwise according to the received instructions. During the adjustment process, the on-site system collects the strain signal output from the strain sensor component in real time. The real-time set pressure characteristic value gradually decreases as the adjusting nut rotates. Real-time data is synchronously transmitted to the calibration software in the remote control room via a 4G network and displayed as a dynamic curve. When the adjusting nut is rotated 70° counter-clockwise, the real-time set pressure characteristic value is 1.995V, and the calculated relative deviation is -0.25%, which is within the allowable error range of ±3%. The remote operator immediately instructs the construction personnel to stop the adjustment and tighten the locking nut. The system continues to collect real-time data for 30 seconds, confirming that the real-time set pressure characteristic value is stable between 1.995V and 2.005V. The calibration software determines that the safety valve has passed calibration, automatically generates an electronic calibration report, and supports electronic signature functionality. The verification report was simultaneously stored in a remote database and on-site FLASH memory. A notification confirming the verification was successful was also sent to the gas company's equipment management manager via SMS alarm module, completing the verification process. The entire verification took 5 minutes, with adjustments taking only 1.5 minutes. The operators completed the main operations entirely from the remote control room.

[0086] The verification method described in this embodiment enables remote verification of safety valves in municipal gas pipelines, achieving a verification accuracy of -0.25%, meeting the requirements of established rules. Operators did not enter the high-risk gas pressure regulating station site, completely avoiding the safety risks posed by natural gas leaks. Data during the verification process was transmitted in real time and automatically stored, enabling visualized monitoring and data traceability of the verification process. The system is powered by lithium batteries, making it suitable for outdoor applications without power supply and providing strong endurance.

[0087] Example 3

[0088] The safety valve to be calibrated in this embodiment is a spring-loaded safety valve in the steam pipeline of a power plant boiler. The nominal pressure of the safety valve is 4.0 MPa, the nominal diameter is DN80, and the standard set pressure is 3.8 MPa. It needs to be calibrated offline on a bench during shutdown maintenance. Traditional offline calibration requires repeated pressure increases and adjustments, which is inefficient and the calibration accuracy is greatly affected by the operator's experience.

[0089] This embodiment uses a circular strain gauge assembly. The inner diameter of the strain gauge assembly matches the 30mm outer diameter of the safety valve stem. The elastic body of the strain gauge assembly is made of chromium vanadium alloy steel, and four constantan foil resistance strain gauges are attached to the surface of the elastic body. The four resistance strain gauges form a full-bridge circuit. After disassembling the safety valve, the operator fixes it to the offline calibration bench, installs the strain gauge assembly between the adjusting nut and the upper clamping block of the safety valve, and tightens the adjusting nut to complete the fixation. The entire installation process takes 5 minutes. The system configuration of this embodiment includes an integrated data acquisition and processing module, a storage module, a comparison and control terminal, an electric actuator module, and a power supply module. The data acquisition and processing module is integrated into the calibration bench control cabinet. The storage module uses a 512M SSD solid-state drive. The comparison and control terminal is the touch screen of the bench control cabinet. The electric actuator module includes a stepper motor, a reduction gear, a clamping mechanism, and a torque sensor. The power supply module adopts a dual power supply mode of AC power and lithium battery. The electric actuator module is fixed to the adjusting nut of the safety valve via a clamping mechanism and is electrically connected to the comparison and control terminal. The torque sensor's torque threshold is set to 50 N·m. After completing the hardware installation and wiring connections, the operator starts the system, performs communication tests on each module and action tests on the electric actuator module, and simultaneously links the booster system of the calibration bench with this system to confirm that the system is functioning correctly.

[0090] Initial calibration is required during the first verification of the safety valve. Operators introduce nitrogen gas into the safety valve through the pressurization system of the calibration bench, gradually increasing the pressure until the valve opens, and recording the standard set pressure value P0 as 3.8 MPa. After the safety valve stabilizes, the data acquisition and processing module acquires the strain signal output by the strain sensor component, converting the strain signal into a standard strain characteristic value V0 of 3.800V, with a range of 0V to 10V. Operators then bind the standard set pressure value of 3.8 MPa and the standard strain characteristic value of 3.800V as historical baseline data, storing this data on an SSD solid-state drive, completing the initial calibration.

[0091] One year after initial calibration, the safety valve entered a shutdown maintenance period and required offline automated calibration. The operator entered the safety valve's equipment number on the touchscreen of the control cabinet. The system automatically retrieved the corresponding historical reference data from the storage module, including the standard set pressure value of 3.8 MPa and the standard strain characteristic value of 3.800 V. The operator clicked the automatic calibration button on the touchscreen, and the system entered automated calibration mode. The data acquisition and processing module acquired the strain signal output by the strain sensor component in real time at a sampling frequency of 250 Hz, converting the strain signal into a real-time set pressure characteristic value Vt of 3.620 V. The comparison and control terminal calculated the relative deviation between the real-time set pressure characteristic value and the standard strain characteristic value. The relative deviation was calculated by subtracting the standard strain characteristic value from the real-time set pressure characteristic value, dividing by the standard strain characteristic value, and then multiplying by 100%, resulting in a final relative deviation of -4.74%. The system's preset allowable error range is ±1%. If the absolute value of the calculated relative deviation is greater than 1% and the relative deviation is negative, it indicates that the current safety valve's set pressure is lower than the standard value, and the adjusting nut needs to be tightened. Based on the previously calibrated strain characteristic value, adding 0.1V corresponds to a 45° clockwise rotation of the adjusting nut. The system calculates an estimated adjustment angle of 81°, compares it with the control terminal, and then sends an adjustment command to the electric actuator module, specifying a clockwise rotation of 81°.

[0092] After receiving the adjustment command, the electric actuator module drives the stepper motor to rotate 81° clockwise. During the adjustment process, the torque sensor monitors the rotational torque in real time, and the data acquisition and processing module simultaneously acquires the strain signal output by the strain sensor component. The real-time set pressure characteristic value increases linearly with the increase of the rotation angle, and the real-time data is dynamically displayed on the touch screen. When the electric actuator module rotates to 81°, the real-time set pressure characteristic value is 3.798V, and the calculated relative deviation value is -0.05%, which is within the allowable error range of ±1%. The comparison and control terminal immediately issues a stop command, and the electric actuator module stops. Subsequently, the system links with the test bench pressurization system to perform a verification pressurization. When the medium pressure rises to 3.805MPa, the safety valve opens naturally, and the deviation between the actual opening pressure and the standard value is 0.13%, verifying the validity of this verification result. The system automatically generates an electronic verification report, enters the verification opening pressure data into the report, stores the electronic verification report to an SSD solid-state drive, and uploads it to the power plant equipment management platform. The operator prints a paper report for archiving, completing this verification operation. The entire automated verification process took 3 minutes, with the adjustment process taking only 40 seconds. The verification process required no manual intervention and no repeated voltage boosting tests.

[0093] The verification method described in this embodiment achieves automated offline verification of boiler safety valves, with a verification accuracy of -0.05%, superior to the accuracy level of traditional offline verification. The electrically operated module replaces manual adjustment operations, reducing the labor intensity of operators and eliminating adjustment errors caused by human experience. The system can be linked with verification benches and enterprise equipment management platforms to automate the storage, uploading, and report generation of verification data, meeting the requirements of refined and digital equipment management in the power industry. The verification process involves only a single verification opening of the safety valve, significantly reducing nitrogen consumption and decreasing wear on the valve disc and seat, thus helping to extend the service life of the safety valve.

[0094] Example 4

[0095] The application scenario of this embodiment is a spring-loaded safety valve for a reaction vessel in a chemical enterprise. The nominal pressure of the safety valve is 2.5 MPa, the standard set pressure is 2.5 MPa, and the standard strain characteristic value V0 is 3.000V. After the safety valve is equipped with the safety valve set pressure verification system of this invention, it is monitored online for a long time. The system collects the strain signal output by the strain sensing component in real time, monitors the change of spring preload, and incorporates it into the enterprise's equipment preventive maintenance system.

[0096] During routine system monitoring, the real-time set pressure characteristic value Vt gradually increased from 3.000V to 3.150V. The calculated relative deviation δ was 5.0%, exceeding the system's preset alarm threshold of ±3%. The alarm module immediately triggered a continuous red light and a continuous buzzer alarm at the site. Simultaneously, an abnormal alarm message was sent to the equipment management manager and on-site maintenance personnel via SMS, clearly indicating the equipment number, current deviation value, and anomaly type. The equipment management manager retrieved the strain signal change curve of the safety valve through the enterprise's remote monitoring platform and found that Vt increased linearly within one hour. This ruled out system sensor and acquisition module malfunctions, concluding that the adjusting nut had loosened due to reactor vibration, causing an abnormal increase in spring preload. Maintenance personnel arrived on-site with a handheld data acquisition and processing terminal and used the system's self-diagnostic function to check the operating status of each module, confirming that the strain sensor component, wireless communication module, and data acquisition and processing module were all functioning normally, with no hardware faults. Based on real-time strain signal feedback from the handheld data acquisition and processing terminal, maintenance personnel manually loosened the adjusting nut. During the adjustment, Vt decreased in real time. When Vt stabilized within the range of 2.990V to 3.010V, the adjustment was stopped and the locking nut was tightened. The system continued to monitor continuously for 24 hours, confirming that Vt remained within the standard error range without drift or fluctuation. The alarm module automatically cleared the alarm, and the maintenance personnel entered the cause of the fault, the handling process, and the adjustment parameters into the system, completing the handling of this anomaly.

[0097] This system provides early warnings of abnormal safety valve spring preload through long-term online monitoring, preventing overpressure hazards in the reactor caused by pressure deviations. The anomaly handling process is based on real-time strain signal feedback, resulting in short adjustment times, no need to shut down the reactor for pressure relief, and no disruption to normal production. All fault handling data is recorded in the system, providing data reference for the maintenance of similar equipment and promoting a shift in equipment management from reactive maintenance to proactive warning and precise in-process handling.

[0098] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0099] The above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made based on the essence of the content of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for verifying the set pressure of a safety valve based on strain sensor feedback, characterized in that, This method is based on a safety valve set pressure verification system, which includes a safety valve body, a strain sensing component, a data acquisition and processing module, a storage module, and a comparison and control terminal. The method includes the following steps: The strain sensor assembly is installed between the adjusting nut and the upper clamping block of the safety valve body to complete the electrical connection and self-test of each component of the system. The safety valve body is calibrated according to standard, the standard set pressure value is recorded, the corresponding strain electrical signal is acquired using the data acquisition and processing module and converted into standard strain characteristic value, the standard set pressure value and standard strain characteristic value are bound as historical reference data and stored in the storage module. The strain electrical signal output by the strain sensing component is acquired in real time using the data acquisition and processing module, converted into a real-time set pressure characteristic value, and transmitted to the comparison and control terminal. By comparing and controlling the historical reference data retrieved from the storage module, the real-time set pressure characteristic value is compared with the standard strain characteristic value, the deviation value is calculated, and an adjustment command or a verification pass command is output based on the deviation value. The adjusting nut of the safety valve body is rotated and adjusted according to the adjustment command. During the adjustment process, the strain electrical signal is collected simultaneously and the real-time set pressure characteristic value is updated until the deviation value falls within the preset allowable error range. After confirming the stability of the real-time set pressure characteristic value by comparing with the control terminal, the verification is deemed qualified, and verification data is generated and stored.

2. The method according to claim 1, characterized in that, When acquiring the strain electrical signal, the strain electrical signal is amplified, filtered and converted from analog to digital by the data acquisition and processing module, and then converted into the real-time set pressure characteristic value or the standard strain characteristic value. When calculating the deviation value, the deviation value is calculated by comparing it with the relative difference between the real-time set pressure characteristic value and the standard strain characteristic value by the control terminal. At the same time, the adjustment direction and estimated adjustment angle of the adjusting nut are determined according to the magnitude and direction of the deviation value.

3. The method according to claim 1, characterized in that, When the adjusting nut is rotated for adjustment, the adjustment process is a real-time closed-loop feedback adjustment. The data acquisition and processing module synchronously updates the real-time set pressure characteristic value and transmits it to the comparison and control terminal. The comparison and control terminal dynamically updates the adjustment command according to the real-time deviation value until the deviation value falls within the preset allowable error range.

4. The method according to claim 1, characterized in that, The system also includes a wireless communication module, which is electrically connected to the data acquisition and processing module and the comparison and control terminal. During the verification process, the real-time set pressure characteristic value and deviation value are transmitted to a remote comparison and control terminal via a wireless communication module. At the same time, the wireless communication module receives adjustment instructions issued by the comparison and control terminal, realizing remote operation of the verification process.

5. The method according to claim 1, characterized in that, The system also includes an electric actuator module, which is electrically connected to the comparison and control terminal and is installed on the outside of the adjusting nut of the safety valve body; After the adjustment command is output, the electric actuator module receives the adjustment command from the comparison and control terminal and automatically drives the adjusting nut to complete the rotation adjustment. During the adjustment process, the electric actuator module monitors the rotation torque in real time to prevent damage to components.

6. The method according to claim 1, characterized in that, After the verification is deemed successful, an electronic verification report is automatically generated by comparison and control terminal. The electronic verification report includes basic information of the safety valve body, historical benchmark data, data of the current verification process, and verification results. The electronic verification report and the entire process data of the current verification are stored in the storage module, and remote data uploading and local printing are also supported.

7. The method according to claim 1, characterized in that, The system also includes an alarm module, which is electrically connected to the comparison and control terminal; During the verification process, if there is a sudden change in the strain signal, the deviation value exceeds the preset alarm threshold, or the component communication is abnormal, the alarm module will be triggered by comparison and control terminal to issue an alarm signal, and the cause of the fault will be indicated at the same time.

8. The method according to claim 1, characterized in that, After verification, the system performs self-diagnosis of the working status of each component through comparison and control terminal, organizes, backs up and maintains the historical benchmark data and verification process data in the storage module, and realizes the operation data management of the safety valve body throughout its entire life cycle.

9. The method according to claim 1, characterized in that, The strain sensing component includes an elastic body and a resistance strain gauge. The resistance strain gauge is attached to the stress-bearing surface of the elastic body, and the strain electrical signal is acquired through a full-bridge circuit layout. When installing the strain sensor assembly, place the strain sensor assembly on the outside of the valve stem of the safety valve body, so that the upper and lower surfaces of the strain sensor assembly are in close contact with the bottom end face of the adjusting nut and the top end face of the upper clamping block, respectively, to complete the non-destructive installation.

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