The magnetic flap level gauge, a liquid level measuring instrument that can be seen everywhere in the industrial field, has its core mystery in a sophisticated "magnetic force" coupling transmission system. It does not require electricity and can achieve clear and prominent liquid level indication through physical principles alone. Behind it is the tacit "dialogue" between the float, magnetic system, and flip column.
Act 1: Buoyancy driven, magnetic source in place
The entire process begins with the buoyancy of the liquid. The float in the main pipeline of the liquid level gauge is designed to have a density between the measured liquid and gas. When the liquid level rises, the float is subjected to upward buoyancy and moves upwards along the main pipeline; On the contrary, when the liquid level drops, the float synchronously follows the descent under the action of gravity. The float has become a mechanical replica of the liquid level.
The key is that the float is embedded with a set of strong magnets (magnetic steel) inside. This makes the float a moving magnetic field source. Its motion essentially converts the information of liquid level changes into the movement of magnetic field positions.
Act 2: Magnetic coupling, airborne communication
Adjacent to the main pipeline, there is a display panel consisting of many independent small flip columns enclosed. Each flip column is a miniature "magnetic sensitive switch": it is usually a cylindrical small piece supported by a rotating shaft at the center, with prominent colors (such as red and white) painted on both sides, and more importantly, magnetic steel embedded inside the flip column.
Although the float and the flip column are isolated by the main pipeline wall, the magnetic field can penetrate this non-magnetic metal wall (such as stainless steel) completely. When the float moves with the liquid level to a certain height of the flip column, its strong magnetic field couples with the magnet inside the flip column.
Act Three: Magnetic Pole Effect, Flip and Change Color
This coupled magnetic force is the 'invisible hand' that drives the flipping of the column. The magnetic fields of the float and the magnet inside the flip column are specially designed to repel and attract each other. When the magnetic field of the float approaches, it applies a torque that forces the flip column to rotate 180 degrees.
The colors on both sides of the flip column have specific meanings: usually, the side facing the observer, red represents liquid, and white represents no liquid. When the float passes through a flip column that originally displayed white (no liquid), the magnetic force will drive it to flip, turning the red surface towards the observer; When the liquid level drops and the float leaves, the direction of magnetic force changes, and the flipping column is driven back, displaying white.
Summary: Exquisite "magnetic force" closed loop
In short, the working password of the magnetic flap level gauge is: liquid level change → buoyancy driven float → float magnetic field displacement → magnetic coupling driven flip column flip → color change indicating liquid level. This series of actions is completed in an instant, forming a stable, reliable, and non powered visual indication system. It is precisely this clever "magnetic force" conversion that turns intangible liquid levels into clear and visible color bands, becoming the "eyes" in industrial processes.