Monitoring of Magnetic Circuit of Electromagnetic Flow Meter in Measurement Process

Abstract

Three factors have the influence for transfer coefficient of magnetic circuit of electromagnetic flow meter: diminution of permeability of core, magnetic sediments on the internal wall of duct and magnetic admixtures in the fluid. These factors can be controlled by two coils on the external wall of duct. The first coil must be situated under of the core and axes of the coil and of the core must coincide. The second coil must be situated near of the side of the core, and the axis of this core must be parallel to straight line connected the electrodes. If the permeability of core is diminished, the signal will diminish in both coils, if magnetic admixtures are appeared in the fluid, the signal will increase in both coils and if the magnetic sediment is appeared on the internal wall of duct, the signal of the first coil will increase and the signal of the second coil will diminish. The formation of sediment can be controlled very effective because the signals of both coils change greatly than the transfer coefficient of meter. If the data of measurement results are accumulated in the memory of processor, the processes that happened inside the duct can be investigated. Ill.. 3, bibl. 6 (in Lithuanian; summaries in Lithuanian, English, Russian).