是利用在流体中设置三角柱型旋涡发生体，则从旋涡发生体两侧交替地产生有规则的旋涡，这种旋涡称为卡门旋涡（类似于旗杆后面旗子的 Vortex flowmeters use triangular vortex generators in the fluid to generate regular vortices from both sides of the vortex generators. This vortex is called a Carmen vortex (similar to the flag behind the flagpole).
Drift), the frequency of the vortex is directly proportional to the flow velocity.
Vortex flowmeters are mainly used to measure the flow of medium fluids in industrial pipelines, such as gases, liquids, vapors and other media. At present, there are many domestic manufacturers of vortex flowmeters, and the product quality is also uneven, which has caused
There are also many problems in the process of use, which cause a lot of inconvenience to the user. Here are some of the main problems and causes of vortex flowmeters for users' reference.
First, the common problems of vortex flowmeters are:
1. Always without instructions;
2. The instructions are not allowed for a long time;
3. The instruction does not return to zero;
4. Indication of large-scale fluctuations, unable to read;
5. The indication is okay when the flow is large, and the indication is not accurate when the flow is small;
6, no indication at small flows;
7. Indication change cannot keep up when the flow changes;
8. The K factor of the instrument cannot be determined, and the data are inconsistent in many places.
2. Summarize the main causes of these problems, mainly related to the following aspects:
1. Problems occurred during selection.
的测量下限决定的。 This is mainly determined by the lower measurement limit of the vortex flowmeter . Some vortex sensors have a large selection on the caliber selection or after the design selection due to process conditions changes-a specification, the actual selection should be selected
The diameter is as small as possible to improve the measurement accuracy. For example, a vortex street pipeline is designed to be used by several devices. Because the process part of the equipment is sometimes not used, the current actual flow rate is reduced, and
As a result, the size of the original design is too large, which is equivalent to increasing the lower limit of the measurable flow. The indication of the small flow of the process pipeline cannot be guaranteed. It can be used when the flow is large, because it is sometimes too difficult to rebuild. work
Changes in artistic conditions are only temporary. Can be combined with parameter re-tuning to improve the indication accuracy.
2. A problem occurred during 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 installation point is too close to the pump, regulating valve and other equipment, which may cause vibration to affect the measurement during work, or there may be other vibration, high frequency,
High-pressure equipment affects the normal operation of the flowmeter.
3. Problems with instrument settings.
Due to the wrong parameter setting, the meter indication is incorrect. Mainly check the meter coefficient, set pressure (temperature) and actual working pressure (temperature).
4. Problems with signal line connection.
Some circuits have good circuit connections on the surface. Check carefully. Some connectors have actually loosened and caused circuit interruptions. Although some connectors are tightly connected, the screws are fastened to the wire cover due to the problem of the auxiliary line.
The circuit is interrupted.
5. The connection between the secondary instrument and the subsequent instrument. The mA output circuit of the secondary meter is interrupted due to a problem with the subsequent meter or the maintenance of the subsequent meter. For this type of secondary meter, especially
For subsequent recorders, if the recorder is damaged for a long time and cannot be repaired, it is necessary to pay attention to shorting the output of the secondary meter.
6, the use of environmental issues.
Especially the sensor part installed in the ground well, due to the high ambient humidity, which caused the circuit board to be damp. Through corresponding technical reform measures, some sensors with high ambient humidity were re-separated from the probe part and the conversion part.
The processing was changed to a separate sensor, so the working environment was improved, and this part of the instrument was running well a few days ago.
7, due to the on-site adjustment is not good, or due to the actual situation after the adjustment.
Due to poor on-site vibration and noise balance adjustment and sensitivity adjustment. Or because of changes in the on-site conditions after running for a period of time after adjustment, causing indication problems. 都有灵敏度和触发 General vortex flowmeters have sensitivity and trigger
The level can be adjusted appropriately at the scene.
8. The last thing to pay attention to is the conversion of flow units.
Such situations are also more common on the site. Pay special attention to the conversion of mass and volume, volume standard flow and working flow.