是根据卡门（Karman）涡街原理测量气体蒸汽或液体的体积流量、标况的体积流量或质量流量的体积流量计。 LUGB type vortex flowmeter is a volume flowmeter that measures the volume flow, standard volume flow or mass flow of gas vapor or liquid according to the Karman principle. The screen can be used as a flow transmitter in automatic control systems.
The instrument adopts advanced differential technology and cooperates with isolation, shielding, filtering and other measures to overcome the problems of poor seismic resistance and small signal data disorder of similar products. The screen adopts unique sensor packaging technology and protective measures to ensure product reliability. . The product has basic type and compound type, and the basic type measures a single flow signal; the composite type can simultaneously measure temperature, pressure and flow. Each type has an integrated and split structure to suit different installation environments.
1. No moving parts, long-term stability, simple structure, easy to install and maintain
2. Using anti-disturbance circuit and anti-vibration sensor head, it has certain anti-vibration performance
3.Using ultra-low power single-chip microcomputer technology, one 3.2V 10AH lithium battery can be used for more than 5 years
4. Correct the instrument coefficient non-linearity by software to improve the measurement accuracy
5. Small pressure loss and wide measuring range
6. Use EEPROM to protect the accumulated flow from power failure, the protection time is more than 10 years
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漂动），该旋涡的频率与流速成正比。 The vortex flowmeter uses a triangular cylindrical vortex generator in the fluid, and regularly generates vortices alternately from both sides of the vortex generator. This vortex is called a Carmen vortex (similar to the floating of the flag behind the flagpole). The frequency of the vortex is 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. This has caused more problems in the use process and caused a lot of inconvenience to users. Here are some of the main emergence of vortex flowmeters. The problems and their causes are 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 been selected on a caliber or after design and selection due to changes in process conditions, which makes the selection larger. The actual selection should choose the smallest caliber as possible to improve the measurement accuracy. For example, a vortex street pipeline It is designed to be used by several equipments. Because the process equipment is sometimes not used, the current actual flow is reduced. The actual use caused the original design to be selected too large, which is equivalent to increasing the lower limit of the measurable flow and the small flow of the process pipeline. The time indication cannot be guaranteed, and it can be used when the traffic 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. 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 operation, or there may be other equipment that generates vibration, high frequency and high pressure near the installation, which affects the normal operation of the flow meter. 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 look good on the surface of the circuit. Carefully check that some connectors are actually loose and cause the circuit to be interrupted. Although some connectors are tightly connected, the screws are fastened to the wire cover due to the problem of the auxiliary line, which also makes the circuit Break. 5. The connection between the secondary instrument and the subsequent instrument. The mA output circuit of the secondary meter was interrupted due to a problem with the subsequent meter or the maintenance of the subsequent meter. For this type of secondary meter, especially for the subsequent recorder, if the recorder's long-term damage cannot be repaired Be sure to pay attention to the output of the short-circuit secondary instrument. 6, the use of environmental issues. Especially the sensor part installed in the ground well, due to the high environmental humidity, the circuit board is damp. Through corresponding technical reform measures, the sensor with high environmental humidity has been re-separated from the probe part and the conversion part. Type sensor, it is good for the working environment, this part of the instrument is 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. Generally, the vortex flowmeter has sensitivity and trigger level adjustments, which can be adjusted appropriately in the field. 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.