Sep. 25, 2020
In liquid chemical production such as petroleum refining, the incoming and outgoing materials of the device are mainly steam, gas energy, and liquid raw materials and products. These materials require high-precision metering instruments. Therefore, the production workshop has very strict requirements on the metering instruments for the incoming and outgoing materials of the device. .
Common failures and analysis of mass flow meters
Failures in the use of mass flowmeters are generally divided into measurement failures caused by process reasons and failures caused by damage to the flowmeter itself.
Measurement faults caused by process reasons:
The most common is the phenomenon of two-phase flow in the measured fluid. Specific to the measurement of liquid, the main reason is that the measured liquid is not filled with the flow meter measuring tube or the upper part of the measuring tube accumulated gas, or solid impurities enter the measuring tube to be stuck in the main body, which causes the mass flowmeter to alarm.
Treatment method: Ensure that the fluid measured by the mass flow meter is one-way flow by changing the installation method of the exhaust gas, and take measures to remove the solid impurities in the measuring tube.
Damage to the mass flowmeter itself causes flowmeter failure:
The most common faults in use are water in the flow meter junction box or loose wiring that causes short circuits and signal loss.
Treatment method: In addition to strictly standardizing on-site installation, daily detailed inspection and maintenance are also required to prevent more serious failures such as the sensor coil burned out due to untimely handling.
The transmitter circuit board is damaged. The most common fault is the damage of the transmitter's power supply board and signal processing output board.
Solution: In addition to strictly standardizing the cable signal wiring, it is also necessary to take measures to prevent lightning and grounding. Use an independent stabilized power supply to ensure the reliability of the power supply and prevent large fluctuations in the power supply voltage from burning the device.
Maintenance of mass flowmeter
As long as you pay attention to some details during the installation process, the mass flowmeter is almost maintenance-free after it is put into operation, and the probability of failure is very small. As long as it is ensured that the medium is not in a two-phase flow state during the flow process, stable operation can be achieved.
Perform some simple settings during the first commissioning of the mass flowmeter, such as the form of the output signal, the various coefficients of the flowmeter itself, the density of the medium in use, the upper and lower temperature limits, etc., basically before commissioning No need to change after setting.
The above information is provided by flow instrument manufacturer.