Common faults and treatment methods of vortex flowmeter in use

Common faults and treatment methods of vortex flowmeters during use. Vortex flowmeters are mainly used for flow measurement of industrial pipeline fluids, such as gas, liquid, vapor and other media. By setting a triangular cylindrical vortex generator in the fluid, regular vortices are alternately generated from both sides of the vortex generator. This type of vortex is called Karman vortex. The vortex array is common in the downstream of the vortex generator during use. Faults and treatment methods Vortex flowmeters are mainly used for flow measurement of industrial pipeline fluids, such as gas, liquid, vapor and other media. By setting a triangular cylindrical vortex generator in the fluid, regular vortices are alternately generated from both sides of the vortex generator. This type of vortex is called Karman vortex, and the vortex array is arranged asymmetrically downstream of the vortex generator. Common problems of vortex flowmeters mainly include: 1. Long-term inaccuracy of indication; 2. No indication at all times; 3. Large range of indication fluctuates and unable to read; 4. The indication does not return to zero; 5. There is no indication when the flow rate is small; 6. Large The indication is OK when the flow rate is small, and the indication is not accurate when the flow rate is small; 7. The indication change cannot keep up when the flow rate changes; 8. The K coefficient of the instrument cannot be determined, and many data are inconsistent. Summarizing the main reasons for these problems, mainly related to the following aspects: 1, the selection of the problem. Some vortex sensors choose a larger size due to changes in process conditions after the selection of the caliber or after the design and selection. The actual selection should choose the smallest caliber possible to improve the measurement accuracy, for example, a vortex pipeline It is designed to be used by several equipments. Because the process equipment is sometimes not used, the current actual use flow is reduced. Actual use causes the original design selection to be too large, which is equivalent to increasing the lower limit of the measurable flow, and the process pipeline has a small flow. The time indication cannot be guaranteed, and it can be used when the traffic is large, because it is sometimes too difficult to remodel. Changes in process conditions are only temporary. It can be combined with the re-tuning of the parameters to improve the accuracy of the indication. 2. Problems with installation. The main reason is that the length of the straight pipe section in front of the sensor is not enough, which affects the measurement accuracy. For example, the straight pipe section in front of the sensor is obviously insufficient. Since FIC203 is not used for measurement but only for control, the current accuracy can be used equivalent to degraded use. 3. The reason for the parameter setting direction. Due to the parameter error, the indicator indication is wrong. The parameter error makes the calculation of the full-scale frequency of the secondary meter wrong. The full-scale frequency is similar, which makes the indication inaccurate for a long time. The actual full-scale frequency is too much. The calculated full-scale frequency makes the indication fluctuate in a large range and cannot be read. The inconsistency affected the final determination of the parameters. Finally, the parameters were determined by re-calibration combined with mutual comparison, and this problem was solved. 4. The secondary instrument is faulty. There are many faults in this part, including: there is a disconnection on the circuit board of the instrument, the display of individual digits in the range setting is broken, and the display of individual digits in the K coefficient setting is broken, making it impossible to determine the range setting and K coefficient setting. Fix the corresponding fault and the problem is solved.　　 5. The four-way line connection problem. On the surface of some circuits, the circuit connection is very good. Check carefully. Some joints are actually loose and the circuit is interrupted. Although some joints are tightly connected, the fastening screws are fastened to the wire skin due to the secondary line problem, which also makes the circuit. Interrupted. 6. The connection problem between the secondary instrument and the follow-up instrument. The mA output loop of the secondary meter is interrupted due to the problem of the subsequent meter or due to the maintenance of the subsequent meter. For this type of secondary meter, especially for the follow-up recorder, if the recorder is damaged for a long time and cannot be repaired , Be sure to short-circuit the output of the secondary instrument. 7. There is always no indication in the circuit due to the failure of the secondary instrument flat shaft cable. Due to the long-term operation and the influence of dust, the flat shaft cable fails. The problem can be solved by cleaning or replacing the flat shaft cable. 8. Some problems are mainly due to the loosening of the fixing screws of the secondary meter display meter coil, which causes the meter head to sink, the pointer and the watch case rub a lot, and the movement does not work well. The problem can be solved by adjusting the meter head and fixing it again. 9. Use environmental issues. Especially for the sensor part installed in the well, the circuit board is damp due to high environmental humidity. Through corresponding technical improvement measures, some sensors with high environmental humidity have been re-separated from the probe part and the conversion part, and the separation is replaced. Type sensor, so the working environment is improved. Recently, this part of the instrument is running well. 10. Due to poor on-site adjustment, or due to further changes in the actual situation after adjustment. Due to the on-site vibration and noise balance adjustment and sensitivity adjustment is not good. Or due to further changes in the site conditions after a period of operation after adjustment, causing indication problems. Use an oscilloscope and re-adjust according to the operating conditions of the process.