Test calibration system of flow transmitter

Abstract

The utility model provides a test calibration system of flow transmitter, including pressure pump, proportional valve, pressure stabilizing cylinder, shrinkage cavity nozzle, test base and control mainboard wherein pressure pump, proportional valve and pressure stabilizing cylinder are communicated through pipeline in proper order, the pressure stabilizing cylinder is provided with the vent hole, the shrinkage cavity nozzle is provided with the tubular structure of through hole, the test base is provided with the test base, the test base is provided with the test base. The testing base is provided with an airflow channel, the flow transmitter is installed on the testing base and communicated with the airflow channel, an air outlet hole of the pressure stabilizing cylinder is communicated with the airflow channel of the testing base through a shrinkage cavity nozzle, and the diameter of a through hole of the shrinkage cavity nozzle is smaller than the diameter of the air outlet hole in the pressure stabilizing cylinder and the diameter of the airflow channel in the testing base; the control main board is connected with the proportional valve and the flow transmitter at the same time, and the control main board controls the proportional valve and collects output signals of the flow transmitter. The system can detect and calibrate the performance of the flow transmitter, and can detect the performance of the train brake board card at the same time.

Description

TECHNICAL FIELD

[0001] The utility model relates to a transmitter technical field especially relates to a kind of test calibration system of flow transmitter. BACKGROUND

[0002] Locomotive air source system is the basis of locomotive air pipeline system, and the locomotive air source system is generally composed of air compressor, air dryer, total air cylinder, pressure controller and various air valves, pipelines and the like, to provide high-quality clean, dry and stable compressed air for locomotive, vehicle brake and locomotive control air. At present, the locomotive air source system can be monitored by brake board card and flow transmitter, and the performance of the brake board card and the flow transmitter directly affects the reliability of the monitoring system. The flow transmitter is a device for measuring and converting fluid flow, and is widely used in industrial automation control systems for monitoring and controlling fluid flow. The performance of the flow transmitter needs to be detected and calibrated when it is shipped and after a long time of use to ensure the reliability of the flow transmitter in use. SUMMARY

[0003] The utility model provides a kind of test calibration system of flow transmitter, the system can realize flow transmitter performance detection and calibration, and the performance of train brake board card can be detected simultaneously.

[0004] To solve the above technical problems, the technical scheme of the utility model is as follows:

[0005] A kind of test calibration system of flow transmitter, the test calibration system of flow transmitter includes pressure pump, proportional valve, pressure stabilizing cylinder, shrinkage nozzle, test base and control mainboard, wherein pressure pump, proportional valve and pressure stabilizing cylinder are sequentially communicated by pipeline, the pressure stabilizing cylinder is provided with gas outlet hole, the shrinkage nozzle is tubular structure with through hole, the test base is provided with airflow channel, the flow transmitter is installed on the test base and communicated with airflow channel, the gas outlet hole of pressure stabilizing cylinder and the airflow channel of test base are communicated by shrinkage nozzle, the through hole aperture of shrinkage nozzle is less than the gas outlet hole aperture on pressure stabilizing cylinder, and the through hole aperture of shrinkage nozzle is less than the airflow channel aperture on test base;Control mainboard is connected with proportional valve and flow transmitter simultaneously, controls proportional valve and collects the output signal of flow transmitter.

[0006] The pressure stabilizing cylinder is a closed tank structure, and a quick connector is arranged on the pressure stabilizing cylinder for connecting the pipeline.

[0007] The gas outlet hole of the pressure stabilizing cylinder is fixedly connected with the shrinkage nozzle through threads, so that the gas outlet hole is communicated with the through hole in the shrinkage nozzle.

[0008] The shrinkage nozzle and the test base are fixedly connected through threads, so that the through hole of the shrinkage nozzle is communicated with the airflow channel of the test base.

[0009] The test base is provided with a mounting hole in communication with the airflow channel, and the flow transmitter is fixedly connected to the mounting hole.

[0010] The test base is provided with mounting holes of different structures for mounting flow transmitters of different models and sizes.

[0011] The control mainboard comprises a processor module, an analog quantity acquisition module and a communication module, wherein the analog quantity acquisition module is connected to the flow transmitter to acquire the 4-20 mA current signal output by the flow transmitter; the communication module communicates with the upper computer to receive and execute test commands of the upper computer and feed back execution results; the processor module is connected to the proportional valve, and the processor module outputs a 4-20 mA current signal to control the proportional valve according to an instruction of the upper computer.

[0012] The control mainboard further comprises a storage module, which stores calibration data when a standard flow transmitter with qualified performance calibrates theoretical values of different gears.

[0013] The control mainboard further comprises two 4-20 mA current loop output modules, which are connected to the train brake board card, and output analog pressure and flow signals respectively under the control of the upper computer, the train brake board card detects changes of the analog signals, and the upper computer displays detection results and determines whether the performance of the train brake board card is qualified.

[0014] The test and calibration system of the flow transmitter further comprises a power board for supplying power to the system.

[0015] Compared with the prior art, the test and calibration system of the flow transmitter provided by the utility model can realize the following functions:

[0016] 1. Performance detection of the flow transmitter: the control mainboard controls the proportional valve to generate different gas flow in the pipeline to detect whether the performance of the flow transmitter is qualified, and sends the detection results to the upper computer.

[0017] 2. Analog pressure and flow output function: the upper computer controls to generate analog flow and pressure signals, the train brake board card detects changes of the analog signals, and the information is uploaded to the upper computer through the control mainboard, and the detection results are displayed on the upper computer to determine whether the performance of the board card is qualified.

[0018] 3. Gear theoretical value calibration function: a standard flow transmitter with qualified performance is used to calibrate theoretical values of different gears under the current environment, which serves as a basis for performance detection of the flow transmitter. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1The utility model provides a flow transmitter's test calibration system's connection schematic drawing is provided;

[0020] Figure 2 The utility model discloses a pressure stabilizing cylinder's structural diagram is provided in the utility model;

[0021] Figure 3 The utility model discloses a test base's structural diagram is provided in the utility model;

[0022] In the drawing, 1-pressure pump, 2-proportional valve, 3-pressure stabilizing cylinder, 31-quick connector, 4-reducing hole nozzle, 5-test base, 51-air flow channel, 52-mounting hole. SPECIFIC EMBODIMENT

[0023] The utility model is further described below in connection with the drawings and examples.

[0024] The utility model provides a flow transmitter's test calibration system as Figure 1 Shown, including pressure pump 1, proportional valve 2, pressure stabilizing cylinder 3, reducing hole nozzle 4, test base 5 and control mainboard (not drawn in the drawing), wherein pressure pump, proportional valve and pressure stabilizing cylinder pass through pipeline and communicate sequentially, and pressure pump outputs high-pressure gas, enters pressure stabilizing cylinder after being controlled by proportional valve and stabilizes pressure, ensures that pressure stabilizing cylinder output gas flow rate is uniform and stable.The proportional valve's parameter in the embodiment is as follows: pressure range: 0.005~0.5MPa;Power voltage: DC 24V;Control input: DC 4~20mA;Analog output: DC 1~5V.The pressure of output gas is controlled through proportional valve, thereby adjusting gas flow rate.Specifically, the pressure stabilizing cylinder is the closed tank body structure, and the quick connector 31 for connecting the pipeline is arranged on the pressure stabilizing cylinder, as shown in Figure 2 .

[0025] The pressure stabilizing cylinder is provided with a gas outlet hole, the reducing hole nozzle is the tubular structure that is provided with through hole, the test base is provided with air flow channel 51, and the pressure stabilizing cylinder communicates with the test base through the reducing hole nozzle, and the flow transmitter is installed on the test base and communicates with the air flow channel.Specifically, the gas outlet hole of the pressure stabilizing cylinder and the air flow channel of the test base communicate through the reducing hole nozzle, and the gas in the pressure stabilizing cylinder flows from the gas outlet hole to the reducing hole nozzle, and then enters the air flow channel of the test base, and the flow transmitter tests the gas flow rate in the air flow channel.Specifically, one end of the reducing hole nozzle is fixed with the gas outlet hole of the pressure stabilizing cylinder through screw thread connection, so that the gas outlet hole and the through hole in the reducing hole nozzle communicate, that is, the gas outlet hole of the pressure stabilizing cylinder and the reducing hole nozzle are respectively provided with matching internal thread and external thread.Specifically, the other end of the reducing hole nozzle is fixedly connected with the test base through screw thread, so that the through hole of the reducing hole nozzle and the air flow channel of the test base communicate.Further, the reducing hole nozzle is provided with internal thread, and the test base is provided with external thread matched with the internal thread, so that the reducing hole nozzle and the test base are connected through screw thread.Specifically, the mounting hole 52 is arranged on the test base, as Figure 3As shown, the mounting hole is in communication with the airflow channel, and the flow transmitter is fixedly connected to the mounting hole. Further, the mounting hole is internally threaded, and the flow transmitter is externally threaded, and the flow transmitter is fixedly connected to the mounting hole by the threads. In this embodiment, two mounting holes of different structures are provided on the test base, which can be used to mount flow transmitters of two different models and sizes.

[0026] In this embodiment, the diameter of the through hole of the convergent nozzle is smaller than the diameter of the gas outlet hole of the pressure stabilizing cylinder, and the diameter of the through hole of the convergent nozzle is smaller than the diameter of the airflow channel on the test base, thereby forming a "convergent nozzle" between the pressure stabilizing cylinder and the test base. The diameter of the through hole of the convergent nozzle can be determined according to the actual required flow rate range. In this embodiment, the diameter of the through hole of the convergent nozzle is 1.5 mm. According to the Venturi effect, when the gas flows through the convergent nozzle, the flow rate of the gas increases, thereby adjusting the flow rate of the gas by adjusting the pressure difference between the pressure of the gas in the pressure stabilizing cylinder and the atmospheric pressure outside (after the gas passes through the test base and directly enters the atmosphere).

[0027] In this embodiment, the control mainboard is connected with the proportional valve and the flow transmitter, controls the proportional valve and collects the output signal of the flow transmitter. Specifically, the control mainboard includes a processor module, an analog signal collection module, a communication module, a storage module, and a two-way 4-20 mA current loop output module. The analog signal collection module is connected with the flow transmitter, collects the 4-20 mA current signal output by the flow transmitter, and calculates the flow value according to the model of the flow transmitter. The communication module communicates with the upper computer through the RS232 interface, so that the processor module receives and executes the test command of the upper computer and feeds back the execution result, i.e., the upper computer receives the detection result of the flow transmitter. The processor module is connected with the proportional valve, and the processor module outputs a 4-20 mA current signal according to the instruction of the upper computer to control the gas pressure at the output end of the proportional valve, thereby affecting the flow rate of the gas flowing through the flow transmitter. The storage module stores the calibration data when the standard flow transmitter with qualified performance calibrates the theoretical values of different gears; specifically, a standard flow transmitter with qualified performance can be installed on the test base to calibrate the theoretical values of different gears under the current environment, thereby providing a basis for performance testing of the flow transmitter to be calibrated.

[0028] The two-way 4-20 mA current loop output module on the control mainboard is connected with the train brake board card, and the communication module receives the instruction of the upper computer through the RS232 interface. Under the control instruction of the upper computer, the processor module on the control mainboard controls the two-way 4-20 mA current loop circuit to output analog pressure and flow signals, respectively. The train brake board card detects the changes of the analog signals and transmits the detection results to the upper computer through the communication module. The upper computer displays the detection results and determines whether the performance of the train brake board card is qualified.

[0029] 4-20mA current loop output module is connected with the host computer, and the 4-20mA current loop output module is connected with the train brake board card at the same time. Under the control instruction of the host computer, the 4-20mA current loop output module outputs analog pressure and flow signals through two 4-20mA current loop circuits, the train brake board card detects the change of the analog signal, the train brake board card is connected with the host computer, and the host computer displays the detection result and determines whether the performance of the train brake board card is qualified.

[0030] The test and calibration system of the flow transmitter in the embodiment further comprises a power board for supplying power to the system. Specifically, the power board has an input voltage of AC 220V and an output voltage of DC 24V, and the power is not less than 10W. The power board should be able to work stably and reliably in the power supply voltage range of AC 175V-AC 265V and the stable environment range of-25℃-+70℃.

[0031] The test and calibration system of the flow transmitter provided in the embodiment can realize the following functions:

[0032] 1. Performance detection of the flow transmitter: the performance of the flow transmitter is detected by controlling the main board to control the proportional valve to generate different gas flow in the pipeline, and the detection result is sent to the host computer.

[0033] 2. Analog pressure and flow output function: analog flow and pressure signals are generated by the host computer control, the change of the analog signal is detected by the train brake board card, and the information is uploaded to the host computer through the control main board, and the detection result is displayed on the host computer, so as to determine whether the performance of the board card is qualified.

[0034] And the detection result is displayed on the host computer, so as to determine whether the performance of the train brake board card is qualified.

[0035] 3. Gear theoretical value calibration function: the theoretical values of different gears under the current environment are calibrated by using the standard flow transmitter with qualified performance, which serves as the basis for the performance detection of the flow transmitter.

Claims

1. A test and calibration system for a flow transmitter, the system comprising: The test calibration system of the flow transmitter comprises a pressure pump, a proportional valve, a pressure stabilizing cylinder, a constricted nozzle, a test base and a control mainboard, wherein the pressure pump, the proportional valve and the pressure stabilizing cylinder are sequentially communicated through pipelines, the pressure stabilizing cylinder is provided with an air outlet, the constricted nozzle is a tubular structure provided with a through hole, the test base is provided with an airflow channel, the flow transmitter is installed on the test base and communicated with the airflow channel, the air outlet of the pressure stabilizing cylinder is communicated with the airflow channel of the test base through the constricted nozzle, the diameter of the through hole of the constricted nozzle is smaller than the diameter of the air outlet of the pressure stabilizing cylinder, and the diameter of the through hole of the constricted nozzle is smaller than the diameter of the airflow channel of the test base; the control mainboard is connected with the proportional valve and the flow transmitter, controls the proportional valve and collects the output signal of the flow transmitter.

2. The test and calibration system for a flow transmitter of claim 1, wherein: The pressure stabilizing cylinder is a closed tank structure, and the pressure stabilizing cylinder is provided with a quick connector for connecting the pipeline.

3. The test and calibration system for a flow transmitter of claim 1, wherein: The air outlet of the pressure stabilizing cylinder is fixedly connected with the constricted nozzle through threads, so that the air outlet is communicated with the through hole in the constricted nozzle.

4. The test and calibration system for a flow transmitter of claim 1, wherein: The constricted nozzle is fixedly connected with the test base through threads, so that the through hole of the constricted nozzle is communicated with the airflow channel of the test base.

5. The test and calibration system for a flow transmitter of claim 1, wherein: The test base is provided with a mounting hole, and the mounting hole is communicated with the airflow channel, and the flow transmitter is fixedly connected with the mounting hole.

6. The test and calibration system for a flow transmitter of claim 1, wherein: The test base is provided with mounting holes of different structures at the same time, which are used for mounting flow transmitters of different models and sizes.

7. The test and calibration system for a flow transmitter of claim 1, wherein: The control mainboard comprises a processor module, an analog quantity collection module and a communication module, wherein the analog quantity collection module is connected with the flow transmitter and collects the 4-20 mA current signal output by the flow transmitter; the communication module communicates with an upper computer, receives and executes the test command of the upper computer and feeds back the execution result; the processor module is connected with the proportional valve, and the processor module outputs a 4-20 mA current signal according to the instruction of the upper computer to control the proportional valve.

8. The test and calibration system for a flow transmitter of claim 7, wherein: The control mainboard further comprises a storage module, and the storage module stores the calibration data when a standard flow transmitter with qualified performance calibrates the theoretical values of different gears.

9. The test and calibration system for a flow transmitter of claim 7, wherein: The control mainboard further comprises two 4-20 mA current loop output modules, which are connected with a train brake board card, and under the control instruction of the upper computer, the two 4-20 mA current loop circuits respectively output analog pressure and flow signals, the train brake board card detects the change of the analog signals, and the upper computer displays the detection result and determines whether the performance of the train brake board card is qualified.

10. The test and calibration system for a flow transmitter of claim 1, wherein: The test calibration system of the flow transmitter further comprises a power board for supplying power to the system.

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