What factors affect the measurement accuracy of mass flowmeter?
The mass flowmeter directly measures the mass flow of the medium through the flowmeter, and can also measure the density of the medium and indirectly measure the temperature of the medium. To accurate measurement data, there can be no influencing factors, but when using the flow meter can not avoid the influence of some factors, in short, some factors affect the measurement and solution of the mass flow meter.
1. The influence of electromagnetic interference on the accuracy of mass flowmeter.
Treatment method: When installing the mass flowmeter, it should be away from large transformers, motors and other equipment that generate large magnetic fields.
2, the impact of vibration on the accuracy of the mass flowmeter.
Treatment method: To avoid vibration interference, if it is impossible to avoid, isolation measures should be taken to isolate the flow meter from the vibration interference source.
3. The influence of installation stress on the accuracy of mass flowmeter.
Processing method: a. flowmeter installation should strictly abide by the installation specifications. b. After the flow meter is installed, use the hand operator or in the transmitter interface to call out the “zero menu” and record the factory zero preset value, and then observe the zero value at this time after the zero adjustment is completed, the two values should be maintained in an order of magnitude, if the difference between the two values is large, it indicates that the installation stress is too large, should be re-installed.
4, the impact of gas in the oil on the accuracy of the mass flowmeter.
Treatment method: a. Improve the working conditions of the oil, so that the bubbles contained in it are evenly distributed as far as possible, and meet the requirements of normal metering of the flowmeter; b. Mass flowmeter upstream installation of gas eliminator, as far as possible to reduce gas-liquid mixing phenomenon; c. Installation in strict accordance with the mass flowmeter installation specifications: the flow tube of the measuring oil medium is installed downward.
5, the influence of temperature change on the accuracy of the mass flowmeter.
Treatment method: a. The influence of temperature on the metal elasticity of the flowmeter measuring tube can be solved by setting the temperature correction coefficient; b. The effect of temperature on the stability of zero point, in practical applications, the mass flow meter needs to be zeroed on site at the operating temperature to reduce the impact to a small extent.
6, the influence of pressure change on the accuracy of the mass flowmeter.
Treatment method: For oil products with large transfer pressure changes and trade handover, it is necessary to install a pressure transmitter in the downstream of the flow meter to carry out real-time pressure compensation by means of software.
7, the impact of oil density and viscosity on the accuracy of mass flowmeter.
Treatment method: The flowmeter should be used to measure a single or small density difference in the oil, for the mass flow meter used for mass oil handover must be calibrated online real flow, and equipped with online density meter.
6, the impact of measuring tube damage or corrosion on the accuracy of the mass flowmeter.
Treatment method: a. The front end of the flowmeter is installed with the corresponding filter to prevent foreign matter from entering; b. Use flowmeters of special materials.
