The vortex flowmeter is a flowmeter produced based on the Karman vortex principle. It is mainly used for flow measurement of industrial pipeline medium fluids, such as gas, liquid, steam and other media. It is characterized by small pressure loss, large range, high accuracy, and is almost unaffected by fluid density, pressure, temperature, viscosity and other parameters when measuring the working volume flow. The vortex flowmeter has no moving mechanical parts, so it has high reliability, low maintenance, and long-term stable instrument performance. When choosing a vortex flowmeter, multiple factors need to be considered, including working conditions, fluid properties, accuracy requirements, etc.
Measured medium
The vortex flowmeter is generally applicable to media such as gas, liquid, and steam, but the following media are not suitable for measurement using a vortex flowmeter:
① Fluids containing more solid particles or suspended matter;
② Media with excessive kinematic viscosity in the working state, such as some high-viscosity oils (such as heavy oil). In addition, for the name of the measured medium, if the medium is steam, it is necessary to indicate whether it is saturated steam or superheated steam.
Pipeline diameter
Depending on the installation method, vortex flowmeters can be divided into pipeline and insertion installation. For pipeline type, the pipeline diameter is the same as most other flowmeters, the smallest is DN15, and the largest can reach DN300.
Measurement accuracy
The accuracy of vortex flowmeters also has several levels, and they are divided according to the measured medium. For pipeline vortex flowmeters, if it is measuring liquid, the measurement accuracy can reach 1.0 level, and if it is measuring gas, the accuracy can reach 1.5 level. If it is an insertion type vortex flowmeter, the accuracy can reach 1.5 and 2.5 levels.
Medium temperature
Generally speaking, it is divided into three ranges: normal temperature, medium temperature and high temperature. The temperature ranges are -40～100℃ (normal temperature), 100～250℃ (medium temperature), 100～320℃ (high temperature). If the on-site medium temperature is higher, such as some superheated steam, it can be measured with an orifice flowmeter.
Installation environment
The vortex signal output method is selected according to the purpose of the vortex flowmeter. There are mainly the following types:
① When the measured medium is a compressible fluid and the on-site medium temperature and pressure change greatly, it is recommended to use a vortex sensor with pulse signal remote transmission and a flow integrator, pressure transmitter, and temperature transmitter with temperature and pressure compensation;
② The vortex flowmeter is installed in a room with a good environment and does not require signal remote transmission. It only needs to read the flow value on site. The installation position of the vortex flowmeter is convenient for operation and data reading. It is recommended that users choose a digital vortex flowmeter;
③ When the installation environment of the vortex flowmeter is poor, or the installation location is not convenient for on-site flow reading, or centralized management is required, it is recommended to use a sensor that outputs pulse signals and is equipped with a flow totalizer, or a vortex transmitter with a 4~20mA standard current output;
④ When the flow needs to be observed on-site and the signal needs to be transmitted remotely, it is recommended to use a digital vortex transmitter with a 4~20mA output;
⑤ When there is no need for on-site reading and only the standard signal needs to be transmitted remotely, it is recommended to use a vortex transmitter with a 4~20mA standard current output.