System and method for sensing leakage of flexible connecting pipe based on pressure difference

Abstract

The invention relates to a system and method for realizing leakage sensing of a flexible connecting pipe based on pressure difference, and the system comprises the components of a flexible connecting pipe which is provided with flanges at two ends; the pressure sensor groups are respectively mounted in preset hole positions of flanges on two sides of the flexible connecting pipe and are used for monitoring pressure values of an inlet and an outlet in real time; the acquisition device is electrically connected with the pressure sensor group and is used for accurately acquiring pressure signals on the two sides; and the microprocessor is electrically connected with the acquisition device and is used for comparing and judging the input pressure signals, dynamically calculating the flow through the pressure difference and judging the leakage state according to a preset threshold value. The pressure sensor mounting holes are reserved in the flanges on the two sides of the flexible connecting pipe, the built-in pressure sensors monitor the pressure difference between the inlet and the outlet of the connecting pipe, and the collecting and analyzing device is externally connected for calculation, so that the leakage of the flexible connecting pipe is monitored in real time. Equipment needed by the leakage monitoring method is simple in structure and convenient to use, meanwhile, the equipment can be additionally arranged on existing equipment, and the maintenance cost is greatly reduced.

Description

Technical Field

[0001] The present invention relates to intelligent monitoring technology for industrial fluid delivery systems, and specifically to a flexible pipe leakage detection system and method based on real-time pressure differential analysis, which is suitable for pipeline health status monitoring in the fields of petroleum, chemical industry, and shipbuilding. Background Art

[0002] In industrial fluid transportation systems, leakage is a common problem, which not only leads to fluid waste, but also may cause environmental pollution and safety hazards. Existing leakage prevention and control technologies mainly focus on preventing leakage, including the research and development of new sealing materials, new fixing technologies at joints, and new dynamic sealing technologies. However, for possible leakage of pipeline fluids, existing fluid transportation systems mainly rely on the installation of liquid level sensors or judgments based on the flow and pressure at the inlet and outlet of the main pipelines, and perform manual inspections after leakage occurs. Due to the complexity of the internal pipeline system and the difficulty of personnel entering and exiting, early leakage is difficult to detect, so leakage monitoring technology for internal pipelines has great practical value.

[0003] As a commonly used connector for fluid delivery pipelines, flexible pipes have good flexibility and sealing properties. In pipeline systems, flexible pipes are widely used to connect different equipment or pipeline sections to absorb vibrations, compensate for displacements, etc. As a connector, the flexible pipe has the function of balancing pressure differences and reducing vibrations. Depending on the working environment of the pipeline and the liquid being transported, rubber aging, improper connection tightening, and incorrect installation may all lead to leakage at the flexible pipe, making it a component that is more prone to leakage. Most flexible pipes currently on the market do not have a leakage detection function. Therefore, designing a method that can realize flexible pipe leakage detection based on pressure difference is of great significance for improving industrial production efficiency and reducing production costs.

[0004] Flexible pipes are prone to leakage due to long-term vibration and pressure fluctuations. Traditional methods rely on manual inspections or static pressure monitoring, which suffer from response lag and high false alarm rates. For example, patent document CN117566082A uses an acceleration sensor to monitor axial displacement, but is unable to detect even small leaks; CN110332469A uses a closed valve to maintain pressure detection, which affects normal system operation. The present invention overcomes these drawbacks and enables non-invasive, real-time monitoring. Summary of the Invention

[0005] To address the problem of leakage in existing flexible pipes and the difficulty in detecting early leaks, this invention proposes a flexible pipe leakage detection system and method based on pressure differential monitoring. By pre-installing pressure sensor mounting holes in the flanges on both sides of the flexible pipe, an internal pressure sensor monitors the pressure differential between the pipe inlet and outlet, and an external data acquisition and analysis device performs calculations, enabling real-time monitoring of flexible pipe leakage. This leakage detection method requires simple equipment and is easy to use. It can also be retrofitted to existing equipment, significantly reducing maintenance costs.

[0006] To achieve the above objectives, the technical solutions of the present invention are as follows:

[0007] A flexible pipe leakage sensing system based on pressure difference, comprising:

[0008] Flexible pipe with flanges at both ends;

[0009] Pressure sensor groups are installed in the preset holes of the flanges on both sides of the flexible pipe, respectively, for real-time monitoring of the inlet and outlet pressure values;

[0010] A collection device, electrically connected to the pressure sensor group, for accurately collecting pressure signals on both sides;

[0011] The microprocessor is electrically connected to the acquisition device and is used to compare and judge the input pressure signal, dynamically calculate the flow rate through the pressure difference, and judge the leakage state according to a preset threshold.

[0012] Furthermore, the flange is a customized flange or a modified flange, the size of the pressure sensor mounting holes thereof matches the selected sensor model, and the holes are located evenly distributed around the circumference of the flange end face.

[0013] Furthermore, the sampling frequency of the pressure sensor group is ≥100 Hz, the measuring range covers 0.1-10 MPa, and the accuracy level is ≤0.5%.

[0014] Furthermore, the microprocessor is composed of a core processor and an editable integrated circuit, and a built-in detection program judges the input signal according to a logic diagram.

[0015] Furthermore, the microprocessor executes a leakage determination algorithm, specifically including:

[0016] Based on the flow formula

[0017]

[0018] Where Q is the flow rate, A is the cross-sectional area of the pipe, C is the flow coefficient, ΔP is the pressure difference, ρ is the fluid density, and the flow rate is calculated in real time;

[0019] When the calculated pressure difference ΔP exceeds the threshold, an alarm is triggered.

[0020] Furthermore, the parameters A, C, and ρ in the flow formula are remotely and dynamically configured through a wireless communication module.

[0021] Furthermore, the wireless communication module supports the LoRaWAN protocol and synchronously sends positioning information and device ID to the cloud platform when an alarm is triggered.

[0022] Furthermore, the system also includes a battery module for providing energy to the acquisition device and a storage component for storing the recorded pressure data to provide more complete monitoring information.

[0023] A flexible pipe leakage sensing method based on pressure difference is provided, which uses the flexible pipe leakage sensing system based on pressure difference to implement the flexible pipe leakage sensing system, including the following steps:

[0024] S1. When the flexible pipe is in operation, the pressure values P1 and P2 on both sides are collected simultaneously;

[0025] S2. Calculate the pressure difference ΔP = |P1-P2| and estimate the real-time flow rate based on the fluid dynamics model;

[0026] S3. When the fluctuation amplitude of ΔP exceeds the historical mean ±3σ, it is judged to be in the early stage of leakage. When ΔP continues to increase and the flow rate decrease rate is greater than 5% / min, it is judged to be worsening leakage.

[0027] Furthermore, the fluid dynamics model in step S2 includes a turbulence correction coefficient of the fluid, the value of which is dynamically optimized according to historical data through a machine learning model.

[0028] The beneficial effects of the present invention are:

[0029] 1. Early warning of leakage: Based on micro-pressure differential sensing technology, it can issue an alarm at the early stage of leakage, avoid accidents, and improve the safety and reliability of the system.

[0030] 2. Real-time flow monitoring: Through the built-in pressure sensor and external collection and analysis equipment, the fluid flow can be monitored in real time, providing accurate data support for flow control and management in the industrial production process, and improving the level of production automation and efficiency.

[0031] 3. Simple structure and easy installation: The pressure sensor installation hole is set on the flange of the flexible pipe. There is no need to carry out large-scale transformation of the existing pipeline system. Only the pressure sensor and corresponding monitoring equipment need to be installed at the pipeline connection to realize flow monitoring and leakage warning functions, which reduces the installation cost and construction difficulty.

[0032] 4. Wide Range of Applications: The flexible pipe body can be made of different materials and is suitable for conveying various types of fluids, such as oil, water, and gas, to meet the needs of different industries. At the same time, the pressure sensor with appropriate range and accuracy, as well as the corresponding data acquisition device and analysis equipment, can be selected according to the actual working conditions, showing excellent versatility and flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a leakage monitoring flow chart of the present invention. DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] The present invention proposes a flexible pipe leakage sensing system and method based on pressure difference monitoring, such as Figure 1 As shown, the main equipment used includes:

[0036] Flanges are located at both ends of the flexible pipe and are used to connect to external piping. Custom flanges can be used or modified on existing flanges. The flanges must have mounting holes for the pressure sensor. The size and location of these holes are designed based on the selected pressure sensor model to ensure secure installation and accurate pressure measurement.

[0037] Pressure sensor: Built into the flange's mounting hole, this device monitors the inlet and outlet pressures of the flexible pipe in real time. The pressure sensor should possess high precision, high sensitivity, and excellent long-term stability, adapting to the fluid's pressure range and operating temperature range. The pressure sensor is connected to a data acquisition device via a signal cable. The data acquisition device, externally connected to the pressure sensor, collects the sensor's output signal and determines leaks by calculating the pressure differential.

[0038] The acquisition device includes an acquisition module with filtering, amplification and other functions for accurately acquiring pressure signals on both sides;

[0039] A battery module, used to provide energy to the collection device;

[0040] Microprocessor, used to compare and judge the input pressure signal and control the functions of other components of the device;

[0041] The storage component is used to store the recorded pressure data and provide more complete monitoring information; the wireless communication component receives the threshold parameter configuration message when installed and sends a leakage detection message when a leakage occurs.

[0042] This is primarily achieved through the following algorithm: When fluid passes through a flexible pipe, the flow of the fluid creates a pressure differential between the pipe's inlet and outlet. A built-in pressure sensor monitors the inlet and outlet pressures in real time and converts the pressure signal into an electrical output. An external data acquisition device receives the electrical signal from the pressure sensor, processes it through filtering and amplification, and then transmits it to a microprocessor for calculation. The microprocessor calculates the flow rate based on the collected pressure differential data, combined with parameters such as the flexible pipe's cross-sectional area and the fluid's density, using the flow calculation formula:

[0043]

[0044] Where Q is the flow rate, A is the cross-sectional area of the pipe, C is the flow coefficient, ΔP is the pressure difference, and ρ is the fluid density. These parameters can be configured using a communication module. The fluid flow rate is calculated according to the formula, and the flow and pressure data are stored. Normal pressure values and flow values are pre-configured, and changes in the pressure difference are monitored in real time using a software algorithm. Under normal circumstances, the pressure value and pressure difference should remain within a preset range. If the pressure value changes suddenly or the pressure difference exceeds the preset threshold, indicating a sudden drop in flow, it may indicate the presence of a leak. This method is characterized by high precision, high sensitivity, and easy integration into existing systems.

[0045] Example:

[0046] Select an appropriate flexible pipe, ensuring that the dimensions and structure of its flanges on both sides meet the requirements for the reserved pressure sensor mounting holes. Reserve mounting holes for the pressure sensor on the inlet and outlet flanges of the flexible pipe and install a high-precision pressure sensor. Based on the specifications and pressure rating of the flexible pipe, select a pressure sensor with the appropriate range and accuracy, and prepare the appropriate data acquisition and analysis equipment. These sensors should be highly sensitive and accurate, capable of accurately measuring even small pressure changes. During installation, ensure that the sensor and flange connections are secure and well sealed to avoid measurement errors caused by improper installation.

[0047] Connect the pressure sensor's signal output to the signal input of the data acquisition and analysis device to ensure stable and reliable signal transmission. The data acquisition and analysis device can be installed in a location easily accessible for observation and operation, such as inside an equipment control cabinet or on a bracket near a pipeline. The detection component consists of a voltage measurement circuit, and the input and output terminals are designed with isolation circuits to prevent interference with the sensor's own signals. The detection module measures the voltage on the incoming cable and uses a microprocessor to compare and determine the voltage. The microprocessor consists of a core processor and an editable integrated circuit. The built-in detection program determines the input signal based on a logic diagram. Users can also batch configure the signal types to be detected and the alarm thresholds through remote access. Based on the judgment results, the microprocessor controls the communication module to send the corresponding measurement communication message. The communication module, consisting of a wireless transceiver circuit and a Bluetooth driver chip, is used to transmit sensor status information and receive external configuration commands.

[0048] Turn on the power of the acquisition and analysis device and debug it to ensure that it can normally collect and display the pressure data monitored by the pressure sensor. Set a reasonable pressure difference alarm threshold so that when the monitored pressure difference exceeds the threshold, the acquisition and analysis device can issue an alarm in time. After debugging is completed, connect the flexible pipe to the pipeline system and start normal operation. The acquisition and analysis device monitors the pressure difference between the inlet and outlet of the flexible pipe in real time. Once a leakage is found, it will issue an alarm in time to remind relevant personnel to deal with it. The acquisition device collects pressure values multiple times per second and calculates the corresponding average signal based on the preset number of samples to reduce noise and improve measurement accuracy. The analysis equipment calculates the flow rate of the fluid based on the collected pressure difference data, combined with the geometric parameters of the flexible pipe and the physical properties of the fluid. If the pressure difference changes abnormally, the alarm system will be triggered.

[0049] Example 1:

[0050] Install this system in an oil pipeline:

[0051] 1. Use 316L stainless steel flange, process the hole according to M12 thread, and install MEMS piezoresistive sensor (range 0-6MPa);

[0052] 2. The acquisition device is embedded with Modbus protocol and seamlessly connects with the existing SCADA system;

[0053] 3. Implementation effect: Successfully detected diesel leakage of 0.5L / min, providing an early warning 2 hours earlier than traditional methods.

[0054] Example 2:

[0055] Ship ballast water system application cases:

[0056] 1. Using LoRaWAN module to achieve 500m wireless transmission in the metal cabin;

[0057] 2. Develop an adaptive algorithm: automatically increase the sampling frequency to 200Hz when the ship rolls >15°;

[0058] 3. Operation and maintenance data shows that the false alarm rate has dropped from 12% with traditional methods to 0.8%.

[0059] The core of this invention is to build a dynamic pressure difference-flow correlation model, and achieve technological breakthroughs through the following innovations:

[0060] 1. Dual-sensor dynamic calibration technology: The pressure sensors on both sides adopt master-slave synchronous sampling to eliminate time error;

[0061] 2. Adaptive threshold algorithm: A dynamic baseline is established based on historical data, and the threshold automatically adjusts according to the working conditions;

[0062] 3. Multi-physics field coupling analysis: Integrating temperature and vibration data improves the reliability of leakage judgment criteria.

[0063] 4. Technical effects:

[0064] (1) Improved sensitivity: It can detect pressure difference changes of 0.1 MPa, an order of magnitude higher than existing technologies;

[0065] (2) Strong compatibility: supports the transformation of in-service pipelines, with installation time less than 2 hours / node;

[0066] (3) Economic benefits: After application in a petrochemical enterprise, the annual maintenance cost was reduced by 37% and unplanned downtime was reduced by 62%.

Claims

1. A flexible pipe leakage sensing system based on pressure difference, characterized in that: include: Flexible pipe with flanges at both ends; Pressure sensor groups are installed in the preset holes of the flanges on both sides of the flexible pipe, respectively, for real-time monitoring of the inlet and outlet pressure values; A collection device, electrically connected to the pressure sensor group, for accurately collecting pressure signals on both sides; The microprocessor is electrically connected to the acquisition device and is used to compare and judge the input pressure signal, dynamically calculate the flow rate through the pressure difference, and judge the leakage state according to a preset threshold.

2. The system according to claim 1, wherein: The flange is a customized flange or a modified flange, the size of the pressure sensor mounting holes thereof matches the selected sensor model, and the holes are located at positions evenly distributed around the circumference of the flange end face.

3. The system according to claim 1, wherein: The sampling frequency of the pressure sensor group is ≥100 Hz, the measuring range covers 0.1-10 MPa, and the accuracy level is ≤0.5%.

4. The system according to claim 1, wherein: The microprocessor is composed of a core processor and an editable integrated circuit, and a built-in detection program judges the input signal according to a logic diagram.

5. The system according to claim 1, wherein: The microprocessor executes a leakage judgment algorithm, specifically including: Based on the flow formula Where Q is the flow rate, A is the cross-sectional area of the pipe, C is the flow coefficient, ΔP is the pressure difference, ρ is the fluid density, and the flow rate is calculated in real time; When the calculated pressure difference ΔP exceeds the threshold, an alarm is triggered.

6. The system according to claim 5, characterized in that The parameters A, C, and ρ in the flow formula are remotely and dynamically configured through the wireless communication module.

7. The system according to claim 6, characterized in that The wireless communication module supports the LoRaWAN protocol and synchronously sends positioning information and device ID to the cloud platform when an alarm is triggered.

8. The system according to claim 1, wherein: It also includes a battery module for providing energy to the acquisition device and a storage component for storing the recorded pressure data to provide more complete monitoring information.

9. A method for sensing leakage of a flexible pipe based on pressure difference, using the flexible pipe leakage sensing system based on pressure difference according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. When the flexible pipe is in operation, the pressure values P1 and P2 on both sides are collected simultaneously; S2. Calculate the pressure difference ΔP = |P1-P2| and estimate the real-time flow rate based on the fluid dynamics model; S3. When the fluctuation amplitude of ΔP exceeds the historical mean ±3σ, it is judged to be in the early stage of leakage. When ΔP continues to increase and the flow rate decrease rate is greater than 5% / min, it is judged to be worsening leakage.

10. The method according to claim 9, characterized in that The fluid dynamics model in step S2 includes a turbulence correction coefficient of the fluid, whose value is dynamically optimized based on historical data through a machine learning model.

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