Sensor performance detection test bed applied to ship and detection method

Abstract

The invention discloses a sensor performance detection test bed applied to a ship and a detection method. The invention relates to the technical field of ship sensor detection, and solves the problem of low efficiency of an existing ship sensor performance detection mode. The invention provides a sensor performance detection test bench applied to a ship. The sensor performance detection test bench comprises a data acquisition and test module, a PLC control module, a display and test module, a data report printing module, a function module and a signal conversion module. According to the sensor performance detection test bed applied to the ship and the detection method, the working environment of workers can be greatly improved, scattered tests are changed into batch tests, on-board operation is changed into workshop infield centralized tests, and the working precision and efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of ship sensor detection, and in particular to a sensor performance detection test bench and a detection method applied to ships. Background Art

[0002] Sensors are an indispensable part of ship construction and automation, and play an extremely important role. The sensors on ships mainly include: temperature, pressure, liquid level, speed, flow, fire alarm and other sensors. Among them, the larger the tonnage of the ship, the more sensors of various types are used. With the increase in the number of sensors used, the higher the degree of intelligence of the ship, it will help to improve the work and life safety of the crew and reduce the occurrence of ship safety accidents caused by human factors. However, in the transportation career of ships, due to the frequent use of ship sensors, long service life and poor working environment, some sensors and instruments have internal structural damage and reduced measurement accuracy. The sensors need to be inspected once a year. In the era of rapid development of intelligent ships, later maintenance measures and tools also need to keep pace with the times. At present, the main way to detect ship sensors is for specialized personnel to carry handheld calibrators or related equipment to various parts of the ship to detect sensors. The main shortcomings of this traditional method of detecting ship sensors are: the ship's engine room is small, resulting in limited detection space for operators, and there are cases where people are injured by collisions in the engine room; some sensors require multiple signals to be input, and due to limited conditions in some areas of the ship's engine room, signals cannot be accessed from the outside; due to the complex distribution of sensors on the ship and the limited detection equipment that the detection operators can carry at one time, the operators need to go back and forth many times and bring different detection equipment to deal with the detection of different sensors; currently, the degree of intelligence of ships is high, and there are a large number of large-tonnage ships, so the detection personnel need a lot of time to detect ship sensors, and the detection efficiency is low.

[0003] The multifunctional testing bench mentioned in the existing patents mainly involves the detection of automotive sensors and the use of professional colleges and universities for teaching. The existing patent CN210862748U provides a multi-purpose automotive sensor detection test bench, which mainly includes a horizontally distributed test bench, a power converter, an oscilloscope, a typical sensor, a sensor to be detected, and a drive motor. Although the invention has a scientific structural design and is easy to operate, it can meet the needs of on-board detection and teaching in colleges and universities, but it is only used for on-board detection and teaching in colleges and universities, and fails to meet the needs of large-scale sensor detection on ships. The equipment performance and stability are poor. The existing patent CN218584261U provides a pressure sensor detection test bench, which is only suitable for pressure detection and is not suitable for the development of ship sensor detection test benches. The existing patent CN115953937A proposes a multifunctional PLC industrial control test bench, which includes a workbench, a support plate, a support mechanism, a crank, a support foot and a mobile structure. The invention solves the problem of dust accumulation in the device by opening a cavity inside the fixed seat, setting a transmission roller in the cavity, and connecting a dustproof cloth to the transmission roller. The adjustment seat drives one side of the protective block to move downward, and the spring is used to achieve a shock-absorbing effect, but the detection system is not specifically described. The patent mainly carries out a shock-absorbing design for mobile teaching devices. The patent does not innovate the structure and working principle of the device for detecting sensors, and is not suitable for testing ship sensors in terms of function and structure. Therefore, it is necessary to propose a sensor performance detection test bench and detection method applied to ships to solve the above problems. Summary of the invention

[0004] The present invention provides a sensor performance detection test bench and a detection method for ships, so as to solve the problem of low efficiency of existing ship sensor performance detection methods.

[0005] In a first aspect, the present invention provides a sensor performance detection test bench for ships, comprising: a data acquisition and test module, a PLC control module, a display and test module, a data report printing module, a function module and a signal conversion module;

[0006] The functional module is connected to the data acquisition and test module, the PLC control module, and the display and test module through a data transmission line and a water source transmission pipeline, and the PLC control module is connected to the data acquisition and test module, the display and test module, and the data report printing module through a data transmission line;

[0007] The data report printing module includes: a Windows control computer, the Windows control computer is connected to an automatic printer via a data transmission line;

[0008] The data acquisition and test module includes: a data acquisition and test platform, a first withstand voltage tester, a first DC regulated power supply, a second DC regulated power supply, a second withstand voltage tester and an inlet and outlet water pipeline; the first withstand voltage tester, the second withstand voltage tester and the first DC regulated power supply and the second DC regulated power supply are connected to each other through a terminal, and the first DC regulated power supply and the second DC regulated power supply provide a voltage signal; a first test installation interface is provided at one end of the inlet of the inlet and outlet water pipeline, and the other end is connected to the outlet end of the inlet and outlet water pipeline; a second test installation interface is provided at the outlet of the inlet and outlet water pipeline, and a signal conversion module is provided in parallel between the inlet and outlet water pipelines, and the signal conversion module includes: a pressure generator, and the signal conversion module is used to provide water pressure for the data acquisition and test module.

[0009] Furthermore, multiple groups of sensors to be tested are respectively arranged in the display and test modules; three groups of detection data displays are also installed on the display and test module, which are used for controlling the heating module, collecting, displaying and curve analyzing the test data; the touch LCD display screen is connected to the PLC control module through the industrial field bus control, and is connected to the host computer operation unit through the data and communication bus, and displays and controls the sensors to be tested.

[0010] Furthermore, the PLC control module is provided with a PLC, which is connected to a Windows control computer through an Ethernet interface to realize the transmission of test data. Each module is controlled by the PLC and connected through a data bus; the PLC adopts the industrial Ethernet communication module in the Siemens expansion module, and the digital output and data input module of the PLC adopts a digital quantity I / O module with 8 digital outputs and 8 digital inputs. The input module of the PLC has an expansion module with two or more input channels, and the output module of the PLC adopts an expansion module with two or more channels; the PLC control modules are installed and fixed on the PLC controller unit platform of the ship sensor detection test bench in sequence, and the corresponding input and output interfaces are connected through connectors.

[0011] Furthermore, the output signal of the PLC is connected to the output signal module, and the output signal module is connected to the first withstand voltage tester. The positive and negative values ​​and the numerical value of the output of the sensor under test are obtained through the display of the numerical value of the first withstand voltage tester; the input channel of the PLC is connected to the sensor to be tested, and the signal is input into the PLC control module by controlling the first DC regulated power supply and the second DC regulated power supply; the signal output by the DC regulated power supply is connected to the upper computer operation unit, and the strength of the signal input into the PLC is displayed through the touch LCD screen in the display and test module.

[0012] Furthermore, the main control system in the PLC control module is a Siemens PCS7 system, the Siemens PCS7 system adopts an industrial field bus communication protocol, the industrial field bus communication protocol converter adopts a PD gateway, the host computer operation unit is connected to the Siemens PCS7 system via Ethernet, the Siemens PCS7 system is connected to the PD gateway via an industrial field bus, and the on-site sensor equipment to be tested is respectively connected to the input and output terminals of the Siemens PCS7 system;

[0013] Siemens PCS7 system configuration includes: installing relevant gateway files under Siemens PCS7 system in PLC control module and hardware configuration of Siemens PCS7 system; hardware configuration of Siemens PCS7 system includes: creating target project under system software of Siemens PCS7 system; adding the name and serial number of actual hardware equipment of Siemens PCS7 system under target project; adding relevant network in the system and specifying gateway address.

[0014] Furthermore, the functional module includes a heating control device and an external pressure generating device, and the heating control device is connected to the system through the functional expansion hardware to realize temperature control; the parameters of the functional module include: a temperature sensor test module and a pressure sensor test module, wherein the low temperature temperature sensor test module can test 2 to 4 sensor analog quantities at the same time; the pressure sensor test module has an adjustable range and can test 2 to 4 sensors at the same time;

[0015] The sensors to be tested include temperature sensors, pressure sensors, liquid level sensors, and speed sensors. The temperature sensors include common switch temperature sensors and analog output temperature sensors. The detection and verification features of common switch temperature sensors and analog output temperature sensors include: verifying the set value of the sensor and conducting an alarm function test by heating the temperature tank in the temperature sensor test module;

[0016] Pressure sensors include common switch pressure sensors and analog output pressure sensors. The detection and calibration features of common switch pressure sensors and analog output pressure sensors include: pressurizing or depressurizing the pressure sensor according to the pressure setting value through a regulated power supply to perform the test;

[0017] The liquid level sensor includes top-mounted and side-mounted float switch liquid level sensors. The testing and calibration process of top-mounted and side-mounted float switch liquid level sensors is as follows: conduct an effective test by raising or lowering the liquid level through the pressure transmission pipeline unit;

[0018] The speed sensor includes contact type and magnetoelectric type sensors, which are verified and tested by observing the sensor pulse curve in the system.

[0019] In a second aspect, the present invention provides a detection method for a sensor performance detection test bench applied to a ship, comprising:

[0020] Step 1: Determine the working mode of the multifunctional test bench control system according to the supply control requirements of the sensor to be tested;

[0021] Step 2: If the working mode is the withstand voltage test mode, proceed to step 3; if the working mode is the pressure relief test mode, proceed to step 4;

[0022] Step 3: Connect with the system in parallel through function expansion to control the pressure increase and decrease, temperature increase and decrease, and medium feeding operation of the multifunctional test bench;

[0023] Step 4: The test bench controls the start and stop of the valve to perform exhaust, pressure reduction, and medium intake operations.

[0024] Further, including:

[0025] When testing a ship's pressure sensor, the steps include:

[0026] Install the ship pressure sensor to be tested on the test installation interface and ensure the sealing of the connection;

[0027] Start the host computer operation unit of the ship sensor detection test bench;

[0028] Check whether the measuring range of the pressure sensor of the ship under test exceeds 6MPa;

[0029] If it does not exceed 6MPa, select a standard pressure sensor with a pressure range of 0 to 6MPa as a reference. If it exceeds 6MPa, select a standard pressure sensor with a pressure range of 0 to 60MPa as a reference.

[0030] Connect the pressure sensor to be tested to the host computer operation unit through a digital-to-analog converter, and debug the input signal source;

[0031] Click the pressurization button to meet the testing requirements;

[0032] The upper computer operation unit displays the detected pressure data, and judges whether the pressurization reaches the maximum value of the pressure sensor according to the pressure range of the pressure sensor being tested. If it does not reach the maximum value, the pressurization operation continues; if it has reached the maximum value, the pressurization operation is stopped;

[0033] Click the decompression button to meet the test requirements;

[0034] The upper computer operation unit displays the detected pressure data, and judges whether the decompression reaches the minimum value of the pressure sensor according to the pressure range of the pressure sensor being tested. If it does not reach the minimum value, the decompression operation continues; if it has reached the minimum value, the decompression operation is stopped;

[0035] The host computer operation unit of the ship sensor detection test bench collects the detected pressure data;

[0036] Compare the pressure curve of the pressure sensor to be tested with the pressure data curve detected by the standard pressure sensor to determine whether the pressure sensor to be tested is working properly. If the data deviation between the pressure sensor to be tested and the standard pressure sensor is greater than the preset threshold, the monitoring system performs a diagnostic action or sends out an alarm signal. If an alarm signal is sent, the sensor should be debugged or replaced.

[0037] Start the data report printing module to print the test report;

[0038] When testing a ship's temperature sensor, the steps include:

[0039] Install the ship temperature sensor to be tested on the test installation interface in the temperature tank and ensure the tightness of the connection;

[0040] Start the host computer operation unit to control and start the entire system;

[0041] Connect the temperature sensor to be measured to the host computer operation unit through a digital-to-analog converter, and debug the input signal source;

[0042] Click the temperature increase button to continue to increase the temperature to meet the test requirements;

[0043] The upper computer operation unit displays the detected temperature data, and judges whether the temperature rise reaches the maximum value of the measured temperature sensor according to the temperature range of the measured temperature sensor. If it does not reach the maximum value, the temperature rise operation continues; if it has reached the maximum value, the temperature rise operation stops;

[0044] Click the cool down button to meet the test requirements;

[0045] The upper computer operation unit displays the detected temperature data, and judges whether the temperature drop reaches the minimum value of the measured temperature sensor according to the temperature range of the measured temperature sensor. If it does not reach the minimum value, the temperature drop operation continues; if it has reached the minimum value, the temperature drop operation stops;

[0046] The upper computer operation unit collects the detected temperature data;

[0047] Compare the temperature curve of the temperature sensor to be tested with the temperature data curve detected by the standard temperature sensor inside the test bench to determine whether the temperature sensor to be tested is working properly. If the data deviation between the temperature sensor to be tested and the standard temperature sensor is greater than the preset threshold, the monitoring system will perform diagnostic actions or send out an alarm signal. If an alarm signal is sent out, the sensor should be debugged or replaced.

[0048] Start the data report printing module to print the test report.

[0049] Further, the working process of the pressure sensor detection is as follows: the pressure sensor program controller is detected. After the power is turned on, the water inlet solenoid valve controls the water inlet, the water inlet solenoid valve is opened, the motor is controlled to rotate forward by the pressurization button, and the water in the water pipe is pressurized by the vacuum pump. When the pressure reaches the maximum value of the standard pressure sensor, the maximum pressure indicator light is on, the operation is stopped, and the decompression operation is performed. The motor is controlled to reverse by the decompression button to decompress the water in the water pipe. When the pressure is reduced to the minimum value of the standard pressure sensor, the minimum pressure reduction indicator light is on, the operation is stopped, and the water outlet solenoid valve is opened to discharge the water in the water pipe. During the whole detection process, the pressure sensor program controller is used to select the pressure detection range of the standard pressure sensor, and the pressure sensor to be tested at the test installation interface is detected;

[0050] The principle of the temperature sensor detection process is as follows: the detection temperature sensor program controller controls the operating equipment. After the power is turned on, the temperature is increased by pressing the heating button to control the electric heating alloy wire to heat the water pipe at the test installation interface, thereby heating the water in the water pipe at that location. When the temperature rises to the maximum value of the standard temperature sensor, the maximum temperature increase indicator light comes on, the heating operation is stopped, and the cooling operation is performed. The temperature is lowered by pressing the cooling button to control the electric heating alloy wire to cool the water pipe at the test installation interface, thereby cooling the water in the water pipe at that location. When the temperature drops to the minimum value of the standard temperature sensor, the minimum temperature drop indicator light comes on, and the operation is stopped. During the entire detection process, the detection temperature sensor program controller compares the temperature sensor to be tested with the standard temperature sensor.

[0051] Furthermore, water medium is used to test the performance of the temperature sensor, and the following theoretical verification is performed to determine whether the heat loss caused by the hot water in the pipeline affects the temperature of the temperature sensor to be tested and the temperature of the standard temperature sensor during detection:

[0052] The total heat loss formula for overhead pipelines is:

[0053]

[0054] Where: ΔQ is the heat loss of the pipeline; t is the temperature of the heat medium in the pipeline; t0 is the ambient temperature around the pipeline; R a is the thermal resistance from the water in the pipe to the inner wall of the pipe; R g is the thermal resistance of the tube wall; R b is the thermal resistance of the insulation material; R w is the thermal resistance from the outer surface of the pipeline insulation layer to the surrounding medium; l is the pipeline length; β is the additional coefficient of heat dissipation loss of pipeline accessories, valves, compensators, and supports, and is 0.25 for overhead laying;

[0055] Thermal resistance R from water in the pipe to the inner wall of the pipe a , the formula is:

[0056]

[0057] Where: ɑ n is the heat release coefficient from the water in the pipe to the inner wall of the pipe; d n is the inner diameter of the pipe;

[0058] Thermal resistance of the pipe wall R g , the formula is:

[0059]

[0060] Where: g is the thermal conductivity of the pipe; d w is the outer diameter of the pipe; d n is the inner diameter of the pipe;

[0061] Thermal resistance R of insulation material b , the formula is:

[0062]

[0063] Where: b is the thermal conductivity of the insulation material; d z is the outer diameter of the outer surface of the insulation layer;

[0064] Thermal resistance R from the outer surface of the pipe insulation layer to the surrounding medium w , the formula is:

[0065]

[0066] Where: α w is the heat release coefficient of the outer surface of the insulation layer to the air, which is obtained using formula (6):

[0067]

[0068] Where: v is the velocity of air flowing from the outer surface of the insulation layer, if v = 0m / s, we get α w =11.6W / m·℃;

[0069] R a =0, R g =0, then formula (1) is simplified to:

[0070]

[0071] Substituting formula (4) and formula (5) into formula (7), we get:

[0072]

[0073] Simplifying formula (8) yields formula (9):

[0074]

[0075] The pipe material from the interface of the temperature sensor to be tested to the detection point of the standard temperature sensor is a galvanized steel pipe. The length of this section of galvanized pipe is 0.3m. The galvanized pipe of model DN80 is selected. According to the standard, the inner diameter of the pipe is 0.08m, the outer diameter of the pipe is 0.0889m, the water temperature in the pipe is 70℃, and the ambient temperature outside the pipe is 20℃; where d z =d w , then the total heat loss in this section of galvanized pipe is:

[0076]

[0077] have to:

[0078] ΔQ=121.43W (11)

[0079] The water in the pipeline first passes through the temperature sensor to be tested and then passes through the standard temperature sensor. Between the temperature sensor to be tested and the standard temperature sensor, the total heat loss of this section of water is 121.43W;

[0080] The mass of water between the temperature sensor to be tested and the standard temperature sensor is m = ρV = 1 × 10 3 ×(3.14×0.04 2 ×0.3)=1.5072(kg), according to the specific heat capacity formula of water, we can get:

[0081]

[0082] Where: Δt is the water temperature change between the temperature sensor to be measured and the standard temperature sensor, m is the mass of water between the temperature sensor to be measured and the standard temperature sensor, and c is the specific heat capacity of water;

[0083] The water temperature between the temperature sensor to be tested and the standard temperature sensor will drop by 0.0192℃, and the temperature difference displayed between the temperature sensor to be tested and the standard temperature sensor is 0.0192℃. According to the shipyard's temperature sensor inspection standard, for temperature sensors with a detection range below 100℃, the temperature difference is qualified within ±3℃.

[0084] The present invention has the following beneficial effects: a sensor performance test bench and a test method for ships of the present invention adopt an industrial field bus control system to test the sensor to be tested, connect the test sensor to the corresponding I / O module of the PLC, develop relevant application software, and automatically collect, store and compare the sensor data with the standard data, which has the advantages of saving the number of hardware and investment, high accuracy and reliability, simple design and easy reconstruction. A plurality of heating and pressurizing control slots are adopted to synchronously test the pressure sensor and temperature sensor to be tested. The heating temperature is controlled by connecting the functional expansion hardware with the system, and the value can be set separately for each sensor. The whole process is stable and reliable, and the assembly and efficient detection process are realized. A modular test bench structure design is adopted, and the data acquisition and test module, the PLC control module, the display and test module, the data report printing module, the function module and the signal conversion module are connected through the PLC control program. The multifunctional test bench integrating temperature, pressure, power, frequency and special sensor detection ensures the accuracy of simultaneous testing of multiple sensors and improves work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0086] Figure 1 This is the overall schematic diagram of the sensor performance test bench used in ships;

[0087] Figure 2 It is a schematic diagram of data collection and test module;

[0088] Figure 3 This is a schematic diagram of the upper computer operation unit;

[0089] Figure 4 This is a schematic diagram of the PLC control module.

[0090] Illustrations: 1-sensor performance test bench; 2-pressure transmission pipeline unit; 3-data report printing module; 4-data acquisition and test module; 5-water source transmission pipeline; 6-host computer operation unit; 7-PLC control module; 4a-data acquisition and test platform; 4b-first withstand voltage tester; 4c-first DC regulated power supply; 4d-second DC regulated power supply; 4e-first test installation interface; 4f-second test installation interface; 4g-second withstand voltage tester; 6a-detection data display; 6b-ordinary switch quantity pressure sensor; 6c-liquid level sensor; 6d-ordinary switch quantity temperature sensor; 6e-host computer mounting platform; 7a-first PLC programmable controller; 7b-PLC control unit mounting platform; 7c-power and power factor sensor; 7d-second PLC programmable controller; 7e-third DC regulated power supply. DETAILED DESCRIPTION

[0091] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The technical solutions provided by the embodiments of the present invention are described in detail below in conjunction with the drawings.

[0092] See also Figure 1 The present invention provides a sensor performance detection test bench for ships. The sensor performance detection test bench 1 includes: a data acquisition and test module 4, a PLC control module 7, a display and test module, a data report printing module 3, a function module and a signal conversion module.

[0093] The function module is connected to the data acquisition and test module, the PLC control module, and the display and test module through a data transmission line and a water source transmission pipeline 5, and the PLC control module is connected to the data acquisition and test module, the display and test module, and the data report printing module through a data transmission line;

[0094] The data report printing module includes: a Windows control computer, the Windows control computer is connected to the automatic printer through a data transmission line;

[0095] The data acquisition and test module includes: a data acquisition and test platform 4a, a first withstand voltage tester 4b, a first DC regulated power supply 4c, a second DC regulated power supply 4d, a second withstand voltage tester 4g and an inlet and outlet water pipeline; the first withstand voltage tester 4b, the second withstand voltage tester 4g and the first DC regulated power supply 4c, the second DC regulated power supply 4d are connected to each other through terminals, and the first DC regulated power supply 4c and the second DC regulated power supply 4d provide voltage signals; a first test installation interface 4e is provided at one end of the inlet of the inlet and outlet water pipeline, and the other end is connected to the outlet end of the inlet and outlet water pipeline; a second test installation interface 4f is provided at the outlet of the inlet and outlet water pipeline, and a signal conversion module is arranged in parallel between the inlet and outlet water pipelines, and the signal conversion module includes: a pressure generator, and the signal conversion module is used to provide water pressure for the data acquisition and test module.

[0096] Multiple groups of sensors to be tested and a host computer mounting platform 6e are respectively arranged in the display and test module; three groups of detection data displays 6a are also installed on the display and test module, which are used for controlling the heating module, collecting, displaying and curve analyzing the test data; the touch LCD display screen is connected to the PLC control module through the industrial field bus control, and is connected to the host computer operation unit 6 through the data and communication bus, and displays and controls the sensors to be tested.

[0097] The PLC control module is provided with a PLC, which includes a first PLC programmable controller 7a and a second PLC programmable controller 7d arranged on a PLC control unit mounting platform 7b. The PLC control module is provided with a power and power factor sensor 7c and a third DC regulated power supply 7e. The PLC is connected to the Windows control computer through an Ethernet interface to realize the transmission of test data. Each module is controlled by the PLC and connected through a data bus; the PLC adopts the industrial Ethernet communication module in the Siemens expansion module, the digital output and data input module of the PLC adopts a digital quantity I / O module with 8 digital outputs and 8 digital inputs, the input module of the PLC has an expansion module with two or more input channels, and the output module of the PLC adopts an expansion module with two or more channels; the PLC control modules are installed and fixed on the PLC controller unit platform of the ship sensor detection test bench in sequence, and the corresponding input and output interfaces are connected through connectors.

[0098] The output signal of the PLC is connected to the output signal module, and the output signal module is connected to the first withstand voltage tester. The positive and negative values ​​and the numerical value of the output of the sensor under test are obtained through the display of the numerical value of the first withstand voltage tester; the input channel of the PLC is connected to the sensor to be tested, and the signal is input into the PLC control module by controlling the first DC regulated power supply and the second DC regulated power supply; the signal output by the DC regulated power supply is connected to the upper computer operation unit, and the strength of the signal input into the PLC is displayed through the touch LCD screen in the display and test module.

[0099] The main control system in the PLC control module is the Siemens PCS7 system, which adopts the industrial fieldbus communication protocol. The industrial fieldbus communication protocol converter adopts the PD gateway. The host computer operation unit is connected to the Siemens PCS7 system via Ethernet, and the Siemens PCS7 system is connected to the PD gateway via the industrial fieldbus. The sensor equipment to be tested on site is respectively connected to the input and output terminals of the Siemens PCS7 system.

[0100] Siemens PCS7 system configuration includes: installing relevant gateway files under Siemens PCS7 system in PLC control module and hardware configuration of Siemens PCS7 system; hardware configuration of Siemens PCS7 system includes: creating target project under system software of Siemens PCS7 system; adding the name and serial number of actual hardware equipment of Siemens PCS7 system under target project; adding relevant network in the system and specifying gateway address.

[0101] The functional module includes a heating control device and an external pressure generating device. The heating control device is connected to the system through functional expansion hardware to achieve temperature control. The parameters of the functional module include: temperature sensor test module and pressure sensor test module. The low temperature temperature sensor test module can test 2 to 4 sensor analog quantities at the same time. The pressure sensor test module has an adjustable range and can test 2 to 4 sensors at the same time.

[0102] The sensors to be tested include temperature sensors, pressure sensors, liquid level sensors, and speed sensors. The temperature sensors include ordinary switch temperature sensors 6d and analog output temperature sensors. The detection and verification features of the ordinary switch temperature sensors and analog output temperature sensors include: verifying the set value of the sensor and testing the alarm function by heating the temperature tank in the temperature sensor test module; the pressure sensors include ordinary switch pressure sensors 6b and analog output pressure sensors. The detection and verification features of the ordinary switch pressure sensors and analog output pressure sensors include: testing the pressure sensor by pressurizing or depressurizing the pressure sensor according to the pressure set value through a regulated power supply; the liquid level sensor 6c includes top-mounted and side-mounted float switch liquid level sensors. The testing and verification process of the top-mounted and side-mounted float switch liquid level sensors is: conducting an effective test by raising or lowering the liquid level through the pressure transmission pipeline unit 2; the speed sensor includes contact and magnetoelectric sensors, and the verification test is performed by observing the sensor pulse curve in the system.

[0103] The pressure-generating equipment in the core functional part of the test bench specifically includes: motor, vacuum pump, water inlet solenoid valve, water outlet solenoid valve, boost solenoid valve, pressure reducing solenoid valve, water pipe. The temperature-generating equipment in the core functional part of the test bench specifically includes: electric heating alloy wire, temperature-increasing solenoid valve, temperature-reducing solenoid valve.

[0104] As can be seen from the above, the present invention provides a ship sensor detection test bench with high technical content and stable equipment performance, which detects various sensors of equipment such as main engines and generators on board, changes the on-site detection test on board to a centralized detection test, and changes the on-board operation to a centralized detection operation, which is simple to operate and has high detection efficiency. The industrial field bus control system is used to automatically collect and store sensor data and compare it with standard data, debug when deviations are found, and print related tests. Other types of control systems have the advantages of cost saving and high accuracy; the present invention detects the temperature sensor through a water medium, and uses continuous heating and continuous cooling to detect during detection to ensure continuity during detection. By comparing the linear temperature changes of the standard temperature sensor and the temperature sensor to be tested during detection, it is determined whether the temperature sensor to be tested can accurately monitor the temperature changes of the equipment on board in real time during operation. The test bench is easy to operate, uses multiple output slot units to test the sensor to be tested in parallel, and uses multiple function expansion hardware to connect with the system to achieve control of variables applied to the sensor. The present invention has higher efficiency and assembly degree. The present invention adopts modular structural design, connects data acquisition and test module, PLC control module, display and test module, data report printing module, function module and signal conversion module through PLC control program, connects with host computer through network technology, debugs and prints relevant test reports. The present invention has simple structure, improves the environment of traditional ship sensor detection, changes scattered tests into batch tests, and changes shipboard detection work into centralized detection work in the workshop, which improves work efficiency while ensuring detection accuracy.

[0105] The detection method of the sensor performance test bench applied to ships includes:

[0106] Step 1: Determine the working mode of the multifunctional test bench control system according to the supply control requirements of the sensor to be tested;

[0107] Step 2: If the working mode is the withstand voltage test mode, proceed to step 3; if the working mode is the pressure relief test mode, proceed to step 4;

[0108] Step 3: Connect with the system in parallel through function expansion to control the pressure increase and decrease, temperature increase and decrease, and medium feeding operation of the multifunctional test bench;

[0109] Step 4: The test bench controls the start and stop of the valve to perform exhaust, pressure reduction, and medium intake operations.

[0110] When testing the ship pressure sensor, the operation steps include: installing the ship pressure sensor to be tested on the test installation interface and ensuring the sealing of the connection; starting the host computer operation unit of the ship sensor detection test bench; checking whether the range of the ship pressure sensor to be tested exceeds 6MPa; if it does not exceed 6MPa, select a standard pressure sensor with a pressure range of 0 to 6MPa as a reference; if it exceeds 6MPa, select a standard pressure sensor with a pressure range of 0 to 60MPa as a reference; connect the pressure sensor to be tested to the host computer operation unit through a digital-to-analog converter, and debug the input signal source; click the pressurization button to meet the detection requirements; the host computer operation unit displays the detected pressure data, and judges whether the pressurization reaches the maximum value of the pressure sensor to be tested based on the pressure range of the pressure sensor to be tested. If it does not reach the maximum value, continue the pressurization operation. If the maximum value has been reached, the pressurization operation is stopped; the decompression button is clicked to meet the detection requirements; the upper computer operation unit displays the detected pressure data, and judges whether the decompression reaches the minimum value of the pressure sensor under test according to the pressure range of the pressure sensor under test. If it has not reached the minimum value, the decompression operation is continued; if it has reached the minimum value, the decompression operation is stopped; the upper computer operation unit of the ship sensor detection test bench collects the detected pressure data; compares the pressure curve of the pressure sensor under test with the pressure data curve detected by the standard pressure sensor to judge whether the pressure sensor under test is working normally. If the data deviation between the pressure sensor under test and the standard pressure sensor is greater than the preset threshold, the monitoring system performs a diagnostic action or sends an alarm signal. If an alarm signal is sent, the sensor should be debugged or replaced; start the data report printing module to print the detection report.

[0111] The working principle of the pressure sensor during detection is that the power supply provides power to the detection pressure sensor program controller, and the detection pressure sensor program controller controls the pressure-generating equipment and the operating equipment. The specific description is as follows:

[0112] The detection pressure sensor program controller controls the pressure-generating equipment, starts the vacuum pump through the motor, controls the water inlet by the water inlet solenoid valve, and then pressurizes the water in the water pipe by the vacuum pump. The detection pressure sensor program controller then selects the pressure detection range of the standard pressure sensor and detects the pressure sensor to be tested at the test installation interface. After the detection is completed, open the water outlet solenoid valve to drain the water in the water pipe.

[0113] The detection pressure sensor program controller controls the operating equipment. After the power is turned on, the water inlet solenoid valve is opened, and the motor is controlled to rotate forward through the pressurization button to pressurize the water in the water pipe. When the pressure reaches the maximum value of the standard pressure sensor, the maximum pressure indicator light comes on, the operation stops, and the decompression operation is performed. The motor is controlled to reverse through the decompression button to decompress the water in the water pipe. When the pressure is reduced to the minimum value of the standard pressure sensor, the minimum pressure reduction indicator light comes on, and the operation stops.

[0114] When testing the ship temperature sensor, the operation steps include: installing the ship temperature sensor to be tested on the test installation interface in the temperature tank and ensuring the tightness of the connection; starting the host computer operation unit to control and start the entire system; connecting the tested temperature sensor to the host computer operation unit through a digital-to-analog converter, and debugging the input signal source; clicking the temperature increase button to continuously increase the temperature to meet the detection requirements; the host computer operation unit displays the detected temperature data, and judges whether the temperature increase reaches the maximum value of the tested temperature sensor according to the temperature range of the tested temperature sensor. If it does not reach the maximum value, continue the temperature increase operation; if it has reached the maximum value, stop the temperature increase operation; click the temperature reduction button to meet the detection requirements; the host computer operation unit displays The detected temperature data is shown, and according to the temperature range of the measured temperature sensor, it is judged whether the cooling reaches the minimum value of the measured temperature sensor. If it does not reach the minimum value, the cooling operation continues; if it has reached the minimum value, the cooling operation is stopped; the upper computer operation unit collects the detected temperature data; the temperature curve of the temperature sensor to be tested is compared with the temperature data curve detected by the standard temperature sensor inside the test bench to judge whether the measured temperature sensor is working normally. If the data deviation between the measured temperature sensor and the standard temperature sensor is greater than the preset threshold, the monitoring system performs a diagnostic action or sends an alarm signal. If an alarm signal is sent, the sensor should be debugged or replaced; the data report printing module is started to print the test report.

[0115] The working principle of the temperature sensor during detection is that the power supply provides power to the detection temperature sensor program controller, and the detection temperature sensor program controller controls the temperature-generating equipment and the operating equipment. The specific description is as follows: The detection temperature sensor program controller controls the temperature-generating equipment, and heats the water pipe at the test installation interface through the electric heating alloy wire, and a standard temperature sensor is installed there to compare with the temperature sensor to be tested. The detection temperature sensor program controller controls the operating equipment. After the power is turned on, the temperature is increased by pressing the heating button to control the electric heating alloy wire to increase the temperature, and the water pipe at the test installation interface is heated, thereby heating the water in the water pipe at that location. When the temperature rises to the maximum value of the standard temperature sensor, the maximum temperature increase indicator light is on, the heating operation is stopped, and the cooling operation is performed. The temperature is lowered by pressing the cooling button to control the electric heating alloy wire to lower the temperature, and the water pipe at the test installation interface is cooled, thereby cooling the water in the water pipe at that location. When the temperature drops to the minimum value of the standard temperature sensor, the minimum temperature reduction indicator light is on, and the operation is stopped. When detecting the temperature sensor, through continuous heating and continuous cooling operations, the working condition of the temperature sensor when detecting temperature changes can be detected in real time. By comparing with the standard sensor to see whether it changes linearly, it can be judged whether the temperature sensor can work normally.

[0116] The present invention uses water as a medium to test the performance of the temperature sensor. When hot water is transported in a pipeline, due to the influence of the external environment, the heat of the hot water in the pipeline will be transferred to the outside world and cause loss. Therefore, a theoretical verification is conducted on whether the heat loss of hot water during transmission in the pipeline affects the temperature of the temperature sensor to be tested and the temperature of the standard temperature sensor during detection:

[0117] The total heat loss formula for overhead pipelines is:

[0118]

[0119] Where: ΔQ is the heat loss of the pipeline; t is the temperature of the heat medium in the pipeline; t0 is the ambient temperature around the pipeline; R a is the thermal resistance from the water in the pipe to the inner wall of the pipe; R g is the thermal resistance of the tube wall; R b is the thermal resistance of the insulation material; R w is the thermal resistance from the outer surface of the pipeline insulation layer to the surrounding medium; l is the pipeline length; β is the additional coefficient of heat dissipation loss of pipeline accessories, valves, compensators, and supports, and is 0.25 for overhead laying;

[0120] Thermal resistance R from water in the pipe to the inner wall of the pipe a , the formula is:

[0121]

[0122] Where: ɑ nis the heat release coefficient from the water in the pipe to the inner wall of the pipe; d n is the inner diameter of the pipe;

[0123] Thermal resistance of the pipe wall R g , the formula is:

[0124]

[0125] Where: g is the thermal conductivity of the pipe; d w is the outer diameter of the pipe; d n is the inner diameter of the pipe;

[0126] Thermal resistance R of insulation material b , the formula is:

[0127]

[0128] Where: b is the thermal conductivity of the insulation material; d z is the outer diameter of the outer surface of the insulation layer;

[0129] Thermal resistance R from the outer surface of the pipe insulation layer to the surrounding medium w , the formula is:

[0130]

[0131] Where: α w is the heat release coefficient of the outer surface of the insulation layer to the air, which is obtained using formula (6):

[0132]

[0133] Where: v is the velocity of air flowing from the outer surface of the insulation layer, if v = 0m / s, we get α w =11.6W / m·℃;

[0134] Thermal resistance R of water in the pipe to the inner wall of the pipe a and the thermal resistance R of the metal pipe wall g Thermal resistance R of insulation material b and the thermal resistance R from the outer surface of the pipe insulation layer to the surrounding medium w Compared with the value, it is very small and can be ignored in actual calculations. a =0, R g =0, then formula (1) is simplified to:

[0135]

[0136] Substituting formula (4) and formula (5) into formula (7), we get:

[0137]

[0138] Simplifying formula (8) yields formula (9):

[0139]

[0140] Since the present invention does not provide insulation material on the outside of the pipe of the test bench, the pipe directly releases heat to the air. Assume that the pipe material from the interface of the temperature sensor to be tested to the detection point of the standard temperature sensor is a galvanized steel pipe, the length of the galvanized pipe section is 0.3m, and the galvanized pipe of model DN80 is selected. According to the standard, the inner diameter of the pipe is 0.08m, the outer diameter of the pipe is 0.0889m, the water temperature in the pipe is 70℃, and the ambient temperature outside the pipe is 20℃. Where d z =d w , then the total heat loss in this section of galvanized pipe is:

[0141]

[0142] have to:

[0143] ΔQ=121.43W (11)

[0144] Since the water in the pipeline first passes through the temperature sensor to be tested and then passes through the standard temperature sensor, the total heat loss of the water between the temperature sensor to be tested and the standard temperature sensor is 121.43W;

[0145] The mass of water between the temperature sensor to be tested and the standard temperature sensor is m = ρV = 1 × 10 3 ×(3.14×0.04 2 ×0.3)=1.5072(kg), according to the specific heat capacity formula of water, we can get:

[0146]

[0147] Where: Δt is the water temperature change between the temperature sensor to be measured and the standard temperature sensor, m is the mass of water between the temperature sensor to be measured and the standard temperature sensor, and c is the specific heat capacity of water;

[0148] The water temperature between the temperature sensor to be tested and the standard temperature sensor will drop by 0.0192°C. Assuming that both the temperature sensor to be tested and the standard temperature sensor can work normally, the temperature difference between the temperature sensor to be tested and the standard temperature sensor is 0.0192°C. According to the shipyard temperature sensor detection standard, the temperature sensor with a detection range below 100°C is qualified if the temperature difference is within ±3°C. Therefore, the structure of the temperature sensor detection device of the present invention is feasible.

[0149] The above-described embodiments of the present invention do not limit the protection scope of the present invention.

Claims

1. A sensor performance test bench for ships, characterized in that: include: Data acquisition and test module, PLC control module, display and test module, data report printing module, function module and signal conversion module; The functional module is connected to the data acquisition and test module, the PLC control module, and the display and test module through a data transmission line and a water source transmission pipeline, and the PLC control module is connected to the data acquisition and test module, the display and test module, and the data report printing module through a data transmission line; The data report printing module includes: a Windows control computer, the Windows control computer is connected to an automatic printer via a data transmission line; The data acquisition and test module includes: a data acquisition and test platform, a first withstand voltage tester, a first DC regulated power supply, a second DC regulated power supply, a second withstand voltage tester and an inlet and outlet water pipeline; the first withstand voltage tester, the second withstand voltage tester and the first DC regulated power supply and the second DC regulated power supply are connected to each other through a terminal, and the first DC regulated power supply and the second DC regulated power supply provide a voltage signal; a first test installation interface is provided at one end of the inlet of the inlet and outlet water pipeline, and the other end is connected to the outlet end of the inlet and outlet water pipeline; a second test installation interface is provided at the outlet of the inlet and outlet water pipeline, and a signal conversion module is provided in parallel between the inlet and outlet water pipelines, and the signal conversion module includes: a pressure generator, and the signal conversion module is used to provide water pressure for the data acquisition and test module.

2. A sensor performance testing bench for ships as claimed in claim 1, characterized in that: Multiple groups of sensors to be tested are respectively arranged in the display and test modules; three groups of detection data displays are also installed on the display and test modules, which are used for controlling the heating module, collecting, displaying and curve analyzing the test data; the touch LCD display screen is connected to the PLC control module through the industrial field bus control, and is connected to the host computer operation unit through the data and communication bus, and displays and controls the sensors to be tested.

3. A sensor performance testing bench for ships as claimed in claim 2, characterized in that: The PLC control module is provided with a PLC, which is connected to a Windows control computer through an Ethernet interface to realize the transmission of test data. Each module is controlled by the PLC and connected through a data bus; the PLC adopts the industrial Ethernet communication module in the Siemens expansion module, the digital output and data input module of the PLC adopts a digital quantity I / O module with 8 digital outputs and 8 digital inputs, the input module of the PLC has an expansion module with two or more input channels, and the output module of the PLC adopts an expansion module with two or more channels; the PLC control modules are installed and fixed on the PLC controller unit platform of the ship sensor detection test bench in sequence, and the corresponding input and output interfaces are connected through connectors.

4. A sensor performance testing bench for ships as claimed in claim 3, characterized in that: The output signal of the PLC is connected to the output signal module, and the output signal module is connected to the first withstand voltage tester. The positive and negative values ​​and the numerical value of the output of the sensor under test are obtained through the display of the numerical value of the first withstand voltage tester; the input channel of the PLC is connected to the sensor to be tested, and the signal is input into the PLC control module by controlling the first DC regulated power supply and the second DC regulated power supply; the signal output by the DC regulated power supply is connected to the upper computer operation unit, and the strength of the signal input into the PLC is displayed through the touch LCD screen in the display and test module.

5. A sensor performance testing bench for ships as claimed in claim 4, characterized in that: The main control system in the PLC control module is the Siemens PCS7 system, which adopts the industrial fieldbus communication protocol. The industrial fieldbus communication protocol converter adopts the PD gateway. The host computer operation unit is connected to the Siemens PCS7 system via Ethernet, and the Siemens PCS7 system is connected to the PD gateway via the industrial fieldbus. The sensor equipment to be tested on site is respectively connected to the input and output terminals of the Siemens PCS7 system. Siemens PCS7 system configuration includes: installing relevant gateway files under Siemens PCS7 system in PLC control module and hardware configuration of Siemens PCS7 system; hardware configuration of Siemens PCS7 system includes: creating target project under system software of Siemens PCS7 system; adding the name and serial number of actual hardware equipment of Siemens PCS7 system under target project; adding relevant network in the system and specifying gateway address.

6. A sensor performance testing bench for ships as claimed in claim 5, characterized in that: The functional module includes a heating control device and an external pressure generating device. The heating control device is connected to the system through functional expansion hardware to achieve temperature control. The parameters of the functional module include: a temperature sensor test module and a pressure sensor test module. The low temperature temperature sensor test module can test 2 to 4 sensor analog quantities at the same time. The pressure sensor test module has an adjustable range and can test 2 to 4 sensors at the same time. The sensors to be tested include temperature sensors, pressure sensors, liquid level sensors, and speed sensors. The temperature sensors include common switch temperature sensors and analog output temperature sensors. The detection and verification features of common switch temperature sensors and analog output temperature sensors include: verifying the set value of the sensor and conducting an alarm function test by heating the temperature tank in the temperature sensor test module; Pressure sensors include common switch pressure sensors and analog output pressure sensors. The detection and calibration features of common switch pressure sensors and analog output pressure sensors include: testing by pressurizing or depressurizing the pressure sensor according to the pressure setting value through a regulated power supply; The liquid level sensor includes top-mounted and side-mounted float switch liquid level sensors. The testing and calibration process of top-mounted and side-mounted float switch liquid level sensors is as follows: conduct an effective test by raising or lowering the liquid level through the pressure transmission pipeline unit; The speed sensor includes contact type and magnetoelectric type sensors, which are verified and tested by observing the sensor pulse curve in the system.

7. A detection method for a sensor performance detection test bench applied to a ship as claimed in claim 6, characterized in that: include: Step 1: Determine the working mode of the multifunctional test bench control system according to the supply control requirements of the sensor to be tested; Step 2: If the working mode is the withstand voltage test mode, proceed to step 3; if the working mode is the pressure relief test mode, proceed to step 4; Step 3: Connect with the system in parallel through function expansion to control the pressure increase and decrease, temperature increase and decrease, and medium feeding operation of the multifunctional test bench; Step 4: The test bench controls the start and stop of the valve to perform exhaust, pressure reduction, and medium intake operations.

8. A detection method for a sensor performance detection test bench applied to a ship as claimed in claim 7, characterized in that: include: When testing a ship's pressure sensor, the steps include: Install the ship pressure sensor to be tested on the test installation interface and ensure the sealing of the connection; Start the host computer operation unit of the ship sensor detection test bench; Check whether the measuring range of the pressure sensor of the ship under test exceeds 6MPa; If it does not exceed 6MPa, select a standard pressure sensor with a pressure range of 0 to 6MPa as a reference. If it exceeds 6MPa, select a standard pressure sensor with a pressure range of 0 to 60MPa as a reference. Connect the pressure sensor to be tested to the host computer operation unit through a digital-to-analog converter, and debug the input signal source; Click the pressurization button to meet the testing requirements; The upper computer operation unit displays the detected pressure data, and judges whether the pressurization reaches the maximum value of the pressure sensor according to the pressure range of the pressure sensor being tested. If it does not reach the maximum value, the pressurization operation continues; if it has reached the maximum value, the pressurization operation is stopped; Click the decompression button to meet the test requirements; The upper computer operation unit displays the detected pressure data, and judges whether the decompression reaches the minimum value of the pressure sensor according to the pressure range of the pressure sensor being tested. If it does not reach the minimum value, the decompression operation continues; if it has reached the minimum value, the decompression operation is stopped; The host computer operation unit of the ship sensor detection test bench collects the detected pressure data; Compare the pressure curve of the pressure sensor to be tested with the pressure data curve detected by the standard pressure sensor to determine whether the pressure sensor to be tested is working properly. If the data deviation between the pressure sensor to be tested and the standard pressure sensor is greater than the preset threshold, the monitoring system performs a diagnostic action or sends out an alarm signal. If an alarm signal is sent, the sensor should be debugged or replaced. Start the data report printing module to print the test report; When testing a ship's temperature sensor, the steps include: Install the ship temperature sensor to be tested on the test installation interface in the temperature tank and ensure the tightness of the connection; Start the host computer operation unit to control and start the entire system; Connect the temperature sensor to be measured to the host computer operation unit through a digital-to-analog converter, and debug the input signal source; Click the temperature increase button to continue to increase the temperature to meet the test requirements; The upper computer operation unit displays the detected temperature data, and judges whether the temperature rise reaches the maximum value of the measured temperature sensor according to the temperature range of the measured temperature sensor. If it does not reach the maximum value, the temperature rise operation continues; if it has reached the maximum value, the temperature rise operation stops; Click the cool down button to meet the test requirements; The upper computer operation unit displays the detected temperature data, and judges whether the temperature drop reaches the minimum value of the measured temperature sensor according to the temperature range of the measured temperature sensor. If it does not reach the minimum value, the temperature drop operation continues; if it has reached the minimum value, the temperature drop operation stops; The upper computer operation unit collects the detected temperature data; Compare the temperature curve of the temperature sensor to be tested with the temperature data curve detected by the standard temperature sensor inside the test bench to determine whether the temperature sensor to be tested is working properly. If the data deviation between the temperature sensor to be tested and the standard temperature sensor is greater than the preset threshold, the monitoring system will perform diagnostic actions or send out an alarm signal. If an alarm signal is sent out, the sensor should be debugged or replaced. Start the data report printing module to print the test report.

9. A detection method for a sensor performance detection test bench applied to a ship as claimed in claim 8, characterized in that: include: The working process of the pressure sensor detection is as follows: detect the pressure sensor program controller, after the power is turned on, the water inlet solenoid valve controls the water inlet, open the water inlet solenoid valve, control the motor to rotate forward through the pressurization button, and pressurize the water in the water pipe by the vacuum pump. When the pressure reaches the maximum value of the standard pressure sensor, the maximum pressure indicator light is on, stop the operation, and perform the decompression operation. Control the motor to reverse through the decompression button to decompress the water in the water pipe. When the pressure is reduced to the minimum value of the standard pressure sensor, the minimum pressure reduction indicator light is on, stop the operation, open the water outlet solenoid valve, and discharge the water in the water pipe; During the whole detection process, the detection pressure sensor program controller selects the pressure detection range of the standard pressure sensor and detects the pressure sensor to be tested at the test installation interface; The principle of the temperature sensor detection process is as follows: the detection temperature sensor program controller controls the operating equipment. After the power is turned on, the temperature is increased by pressing the heating button to control the electric heating alloy wire to heat the water pipe at the test installation interface, thereby heating the water in the water pipe at that location. When the temperature rises to the maximum value of the standard temperature sensor, the maximum temperature increase indicator light comes on, the heating operation is stopped, and the cooling operation is performed. The temperature is lowered by pressing the cooling button to control the electric heating alloy wire to cool the water pipe at the test installation interface, thereby cooling the water in the water pipe at that location. When the temperature drops to the minimum value of the standard temperature sensor, the minimum temperature drop indicator light comes on, and the operation is stopped. During the entire detection process, the detection temperature sensor program controller compares the temperature sensor to be tested with the standard temperature sensor.

10. A detection method for a sensor performance detection test bench applied to a ship as claimed in claim 9, characterized in that: include: The performance of the temperature sensor is tested using water as a medium. The following theoretical verification is performed to determine whether the heat loss caused by the hot water in the pipeline affects the temperature of the temperature sensor to be tested and the temperature of the standard temperature sensor during testing: The total heat loss formula for overhead pipelines is: Where: ΔQ is the heat loss of the pipeline; t is the temperature of the heat medium in the pipeline; t0 is the ambient temperature around the pipeline; R a is the thermal resistance from the water in the pipe to the inner wall of the pipe; R g is the thermal resistance of the tube wall; R b is the thermal resistance of the insulation material; R w is the thermal resistance from the outer surface of the pipeline insulation layer to the surrounding medium; l is the pipeline length; β is the additional coefficient of heat dissipation loss of pipeline accessories, valves, compensators, and supports, and is 0.25 for overhead laying; Thermal resistance R from water in the pipe to the inner wall of the pipe a , the formula is: Where: ɑ n is the heat release coefficient from the water in the pipe to the inner wall of the pipe; d n is the inner diameter of the pipe; Thermal resistance R of the pipe wall g , the formula is: Where: g is the thermal conductivity of the pipe; d w is the outer diameter of the pipe; d n is the inner diameter of the pipe; Thermal resistance R of insulation material b , the formula is: Where: b is the thermal conductivity of the insulation material; d z is the outer diameter of the outer surface of the insulation layer; Thermal resistance R from the outer surface of the pipe insulation layer to the surrounding medium w , the formula is: Where: α w is the heat release coefficient of the outer surface of the insulation layer to the air, which is obtained using formula (6): Where: v is the velocity of air flowing from the outer surface of the insulation layer, take v = 0m / s, and we get α w =11.6W / m·℃; R a =0, R g =0, then formula (1) is simplified to: Substituting formula (4) and formula (5) into formula (7), we get: Simplifying formula (8) yields formula (9): The pipe material from the interface of the temperature sensor to be tested to the detection point of the standard temperature sensor is a galvanized steel pipe. The length of this section of galvanized pipe is 0.3m. The galvanized pipe of model DN80 is selected. According to the standard, the inner diameter of the pipe is 0.08m, the outer diameter of the pipe is 0.0889m, the water temperature in the pipe is 70℃, and the ambient temperature outside the pipe is 20℃; where d z =d w , then the total heat loss in this section of galvanized pipe is: have to: ΔQ=121.43W (11) The water in the pipeline first passes through the temperature sensor to be tested and then passes through the standard temperature sensor. Between the temperature sensor to be tested and the standard temperature sensor, the total heat loss of this section of water is 121.43W; The mass of water between the temperature sensor to be tested and the standard temperature sensor is m = ρV = 1 × 10 3 ×(3.14×0.04 2 ×0.3)=1.5072(kg), according to the specific heat capacity formula of water, we can get: Where: Δt is the water temperature change between the temperature sensor to be measured and the standard temperature sensor, m is the mass of water between the temperature sensor to be measured and the standard temperature sensor, and c is the specific heat capacity of water; The water temperature between the temperature sensor to be tested and the standard temperature sensor will drop by 0.0192℃, and the temperature difference displayed between the temperature sensor to be tested and the standard temperature sensor is 0.0192℃. According to the shipyard's temperature sensor inspection standard, for temperature sensors with a detection range below 100℃, the temperature difference is qualified within ±3℃.

Images