General for the flowmeter selection we will first think of electromagnetic flowmeter and open channel flowmeter, but sometimes very pure medium conductivity is low, or the installation site does not meet the installation requirements of the open channel flow meter how to do it? We have One option - the VNLUGB Worm Street Flowmeter.
The vortex flowmeter has the advantages of simple structure, convenient installation and maintenance, low pressure loss, wide measuring range, long service life and stable performance. The instrument coefficient is not affected by the temperature, pressure, viscosity and composition of Reynolds number range The impact of change and other characteristics, has become more and more people of all ages.
For thevortex flowmeterselection must grasp the four selection parameters, namely the pipe diameter; recent and long-term maximum, minimum and common instantaneous flow; measured medium design pressure; measured medium temperature.
1. Caliber selection
Vortex flow sensor diameter is not necessarily the same diameter with the process pipe, according to the flow rate, flow to a reasonable choice. Vortex flowmeter diameter selection mainly to consider the lower limit of flow, the general measurement of water velocity lower limit of 0.5m / s, the normal flow is best in the measurement range of 1 / 2-2 / 3. Such as
2. Signal output selection
According to the requirements of the acquisition signal to select a different output form, when the need to accumulate flow can be selected pulse output type, when you need to control can choose analog (4-20mADC) output type. In general we will do 4-20mA signal output to the user.
3. Meter installation
Vortex water flowmeter should be installed in the insulation, ventilation, easy to maintain the place, as far as possible away from the vibration source and electromagnetic interference strong place where the vibration must be the use of vibration reduction devices to reduce the pipeline by vibration.
Vortex flowmeter in the pipeline can be horizontal, inclined or vertical installation. Installation location Be aware that liquid media must flow from the bottom up when installed vertically: Temperature, pressure sensors, and regulators should be installed downstream of the meter when a temperature, pressure sensor, or flow control valve needs to be installed on the pipe.
Vortex flow meter must be long enough before and after the straight pipe, pipe diameter must also be consistent with the vortex flow transmitter internal diameter, and pipe connected to the inner diameter of the gasket than the sensor diameter slightly larger, can not be projected into the pipeline gasket Inside.
4. Parameter setting
Meter meter coefficient is calibrated under laboratory conditions, field use, the instrument coefficient should be amended.
5. Routine maintenance
In order to ensure the long-term work of the instrument accuracy, reliability, to avoid accidental outage and data loss, in the flow meter into operation after the need to strengthen the instrument itself and the flow of all aspects of daily management and periodic maintenance.
6. Vortex Street Flowmeter limitations
Vortex flowmeter is essentially a fluid vibration-type flowmeter, it is the external vibration, fluid flow is particularly sensitive to the state. Pipeline vibration, pipeline fluid impact force and due to changes in fluid pressure, the resulting random pulse pressure and so on will have a greater impact on the instrument measurement. Especially in the small flow measurement, the smaller the lateral flow of small lift, the detection signal is weak, vulnerable to shock and vibration of fluid vibration and pipeline vibration noise.
