General principles for electromagnetic flowmeter selection
(1) Whether the medium to be tested is a conductive liquid or slurry, thereby determining whether an electromagnetic flow meter is selected;
(2) The conductivity of the measured medium determines the type of electromagnetic flowmeter—whether it is high conductivity or low conductivity;
(3) The nominal diameter of the large, small and common flow process pipelines required by the process, determine whether the flow rate of the medium is at a more economical flow point, whether the pipeline needs to be reduced, and then determine the diameter of the flowmeter;
(4) Determine whether to use an integrated or split flowmeter, and the degree of protection of the flowmeter, etc., based on the layout of the process piping.
(5) Selecting the electrode type according to whether the measured medium is easy to crystallize or crusting;
(6) selecting an electrode material according to the corrosiveness of the measured medium;
(7) The corrosiveness, wear and temperature of the measured medium determine the lining material to be used;
(8) The high working pressure of the measured medium determines the nominal pressure of the flow meter;
(9) The insulation of the process piping determines the type of grounding ring.
Working principle and sensor parameters of ultrasonic external clamp flow meter
External clip type ultrasonic flow meter external clip type ultrasonic flow meter series measuring full flow of liquid flow meter, optional explosion-proof and intrinsically safe type, explosion-proof grade Exd[ib]IIBT6, and optional intrinsically safe remote control, explosion-proof grade ExibIIBT6, measurable medium: drinking water, river water, sea water, ground water cooling water, high temperature water, sewage, lubricating oil, diesel, fuel chemical liquid, other homogeneous fluid.
External clip sensor parameters:
The external clip type sensor is an installation method in which the sensor is directly bundled on the outer surface of the pipe to be measured to realize flow measurement, and has a diameter independent of the pipe diameter.
Simple installation, no need to stop production, no pressure loss and so on.
Second, the compressed air vortex flowmeter installation steps
1. The special flanges to be equipped are welded to the upstream and downstream straight pipe sections respectively, so that the inner diameters of the special flange and the straight pipe section are strictly vertical and concentric.
2. Install the sensor clip on the upper and lower straight pipe sections welded with special flanges and fasten them with bolts. The upstream and downstream straight sections should be kept concentric with the sensor.
3. It should be noted that the flow direction of the sensor should be consistent with the flow direction of the fluid in the pipeline.
Third, special attention should be paid when installing compressed air vortex flowmeter
1. When welding special flanges and straight pipe sections, the sensor should be removed and the sensor welding flange must not be carried.
2. Before the sensor is installed, the sealing ring must be placed in the groove of the flange.
3. The pressure point and temperature measurement point should be at the 3DN~5DN and 6N~8DN downstream of the sensor.
4. When the high temperature pipeline is insulated, do not wrap the sensor to avoid damage.
5. The cable connecting the vortex flowmeter should be as far away as possible from the interference of strong electromagnetic fields. It is absolutely not allowed to lay with high voltage cables. The shielded cable should be as short as possible, the maximum length should not exceed 500 meters, and should not be coiled to reduce the distributed inductance.