The main faults that vortex flowmeters encounter during use are:
1. The instructions are not allowed for a long time;
2. Always without instructions;
3. Indication of wide range fluctuations, unable to read;
4, instructions do not return to zero;
5. No instructions at small flows;
6. The indication is okay when the flow is large, and the indication is not accurate when the flow is small;
7. Indication change cannot keep up when the flow changes;
Analysis and solution: Summarize the main causes of these problems, mainly related to the following aspects:
1. Selection issues. Some vortex flowmeters have a larger size in the selection of the caliber or after the design selection due to changes in process conditions. The actual selection should choose the smallest caliber as possible to improve the measurement accuracy. The main reason for this is Related to questions ①, ③, ⑥. For example, a vortex flowmeter installation pipeline is designed to be used by several devices. Because the process part of the equipment is sometimes not used, the current actual flow is reduced. The actual use caused the original vortex flowmeter design to be too large in size, which is quite large. As the lower limit of measurable flow is increased, the indication cannot be guaranteed when the process flow is small, and it can be used when the flow is large, because it is sometimes too difficult to rebuild. Changes in process conditions are only temporary. Can be combined with parameter re-tuning to improve the indication accuracy.
2. The length of the straight pipe section in front of the vortex flowmeter is not enough, which affects the measurement accuracy. The reason for this is mainly related to problem ①. For example: the straight pipe section in front of the sensor is obviously insufficient, so the current accuracy can be used equivalent to degraded use.
3. Reason for parameter setting direction. Due to the wrong parameter, the instrument indication is wrong. The parameter error causes the secondary meter full-scale frequency to be calculated incorrectly. The main reason for this is related to problems ① and ③. The full-scale frequency is similar, which makes the indication inaccurate for a long time. The actual full-scale frequency is calculated to make the indication fluctuate widely and cannot be read.