About the instrument, do you know the Venturi sonic nozzle system and its overall structure? Here are more new market trends in the instrument industry

In the flow instrument industry, how do you all view the Venturi sonic nozzle system and its overall structure? Here I have something to say about the Venturi sonic nozzle editor. I hope this article of the editor can play a key role for everyone. Let's explore it together.

When the flowmeter is verified for the sonic nozzle part, after the air passes through the verification pipe section and the calibrated flowmeter, it is selected to pass through the critical flow Venturi nozzle group according to the needs, and then passes through the vacuum generation system or fan, and finally is discharged back to the atmosphere.

A set of verification pipelines is designed for the whole system, and the two verification methods share a set of verification pipelines. In addition to the independent verification of the bell device, the real-time comparison and verification of the sonic nozzle system can also be carried out. According to the needs of verification, select the critical flow nozzle group for flow meter detection. When using the critical flow nozzle group to detect the flowmeter, according to the needs of the detection flow, the system automatically controls the valve to select different nozzle combinations to obtain the required calibration flow. By stabilizing the negative pressure of the buffer container, the back pressure ratio of the nozzle is stabilized, and the critical flow state formed at the throat of the nozzle is guaranteed to be stable; when the standard turbine flowmeter group is used to detect the flowmeter, the valve selection is controlled according to the needs of the detection flow. The combination of standard turbine flowmeter, adjust the flow regulating valve downstream of the standard turbine flowmeter to obtain the required calibration flow. Wait for the standard turbine flowmeter and the tested flowmeter output signal to stabilize.

The gas mass flow through the critical flow nozzle or standard turbine flowmeter is the same as that through the flowmeter under test. Under stable working conditions, the microcomputer system automatically collects and processes the stagnation pressure and stagnation temperature of the airflow before the critical flow nozzle, or the accumulated pulse, pressure and temperature of the standard turbine flowmeter, and calculates the standard gas mass flow and accumulated flow , and according to the relevant verification procedures, compare and calculate it with the collected output of the flowmeter under test to obtain the basic error and repeatability error of the flowmeter under test at different flow points, so as to complete the test of the gas flowmeter. Check.

The nozzle system is designed with a set of diameters: DN15 and below, and DN25 calibration pipelines; various types of air samplers with a flow rate of less than 16m3/h can be calibrated. Each pipeline is equipped with a ROSEMOUNT absolute pressure transmitter with an uncertainty of 0.075%, a temperature transmitter with an uncertainty of 0.2% (±0.1°C), front and rear straight pipe sections, pneumatic ball valves, etc. The calibration pipeline also includes corresponding pneumatic clamps, self-aligning workbenches, adjustable movable brackets, as well as various reducing components and reducing pipe sections. The pneumatic clamp is installed on the clamp table coaxially with the front straight pipe section to ensure the concentricity of the test pipeline itself. There is a manual vertical lift adjustment mechanism on the adjustment workbench. By manually adjusting the center of the flowmeter to be tested, the center of the flowmeter and the center of the calibration pipeline can be installed coaxially. One set of nozzle metering section: including 16 critical flow Venturi nozzles, stagnation container, metering section connection components, nozzle installation assembly, nozzle switch valve, outlet container, connecting short joint, etc., specific pipeline connections.

Well, the above content is only my personal opinion for the time being. If you think there are other things that need to be added, please feel free to call and consult with the editor. There is a 24-hour customer service online to help you at any time; you can also log in at any time. http://www.whliuliangji.com/ Flowmeter, pay attention to the editor, the next issue will be more exciting! What else do you need to know about the flow meter, private message the editor to get more~