The construction and principle of a metal tube magnetic float flowmeter: The magnetic field strength with a magnetic float is measured by a magnetic sensing element, which is equivalent to zero flow rate. The signal proportional to the medium flow rate is amplified and digitized, and its characteristic curve is transformed using microprocessor and software technology, and saved in memory. LCD digital is used for local indication, and a 4-20mA two-wire current output independent of the load is generated.
The float of the metal tube float flowmeter moves upwards with the change of flow rate in the measuring tube, and at a certain position, the buoyancy and gravity of the float reach equilibrium. At this time, the circulation gap area between the float and the orifice plate (or cone tube) remains constant. The annular gap area is directly proportional to the rising height of the float, that is, the position where the float rises in the measuring tube represents the size of the flow rate. The change in the position of the float is transmitted by the internal magnet to the external indicator, so that the indicator correctly indicates the current flow rate value.