How does the Magnetic Flap Level Meter Work

How does the Magnetic Flap Level Meter Work

Working Principle

The magnetic flip-flop level indicator is installed on the outside or above the barrel tank to indicate and control the sealing form. The sewage valve can be installed according to the needs of the tank. The connecting flange can accept customized liquid level height for a control instrument. The indicator comprises a magnetic color film. As the magnetic float within the body tube rises with the liquid level, the color film flips to display the liquid level height.

Magnetic switches or remote transmitters may also be provided on the body tube to output switching signals or analog signals. Suitable for high temperature, high pressure, corrosion-resistant occasions, local display and remote control. The body tube consists of seamless steel tube. Besides, the connection tube is welded by pulling hole, and there is no scratch inside. Installation can choose side and top mounting, the lower end of the body sealed.

magnetic level indicator

Use of Magnetic Flap Level Gauge

Magnetic flap level meter can be directly used to observe the liquid level height of the medium in various containers. It is suitable for level indication in petroleum, chemical and other industries. The liquid level meter has simple structure, clear and intuitive observation, no blockage, no leakage, easy installation and simple maintenance. The upper and lower mounting flanges of the glass level gauge connect to the container, forming a connector. The actual liquid level height can be observed directly through the glass plate. Safety steel beads are equipped on the upper and lower valves. In the event of accidental glass damage, these beads automatically seal under the container’s internal pressure. Consequently, it prevents liquid overflow and ensuring operator safety.

Frequently Asked Questions about Magnetic Flip-Flop Level Gauge


It is a commonplace liquid level measurement instrument in large tanks, operating on the principle of buoyancy. A magnetic flip-flop float resides in the main body (with the container), rising and falling with the tested medium’s level. Utilizing magnetic components within the float, it attracts the flip-flop within the indicator to visually display the level change in the tested container.

The magnetic flap level meter serves as an effective tool for directly observing the liquid level in various containers. It is highly suitable for liquid level indication in industries such as petroleum, chemical, and others. Whether applied to towers, tanks, spherical containers, boilers, or other equipment, its simple structure, intuitive observation, and easy maintenance make it a preferred choice. Users appreciate its advantages, including clear visibility, no clogging, no leakage, and straightforward installation.

As the ideal liquid level detection instrument for in situ display, the magnetic flap level meter’s manufacturing process demands strict testing and control of product parts, components, and assemblies. The rapid development of the industry has been made possible by advanced and applicable measurement technology, using information technology to modernize science and technology. This development has shortened the distance between people and enhanced the attractiveness and authority of the industry. Current trends are focused on increasing speed, simplifying the complexity of installation and commissioning, expanding wireless capabilities and advancing technology.

Magnetic Level Gauge


The magnetic flap level meter industry faces evolving requirements for product stability, reliability, and adaptability. The technical indicators and functions of Magnetic Flap Level Gauges are constantly improving, both in terms of production value and market share. Consequently, it establishes their cornerstone position in instrumentation and measurement control systems. Instrumentation equipment serves a variety of purposes and plays a vital role in production activities. Different level meters are used to continuously and accurately measure liquid levels and interface heights in a variety of vessels.

Occasionally, issues may arise where the float lacks flexibility during field calibration. Typically caused by improper installation, attention should be given to ensuring the upper and lower flange centers align in a line and are perpendicular to the horizontal plane. Generally, it is essential to maintain an angle with the horizontal plane of not less than 87 degrees, as significant deviations may impact the smooth movement of the float.

Common Problems with the Magnetic Flap Level Meter

“Sucked” Phenomenon

After normal adjustment, users may notice the float remaining in one position for a period. It often results from the close distance between the magnetic flap level meter and the steel platform during installation. Special attention should be given to the spacing between the liquid level meter connecting pipe and the platform’s cutting edge line, with a recommended distance of approximately 100mm to avoid interference with the magnetic float.

Gate Valve Sequence

During on-site usage, it’s crucial to open the upper gate valve first and then the lower gate valve. The protection float thrust spring at the bottom of the level meter is the reason for taking this precaution. It prevents potential float crushing caused by significant differential pressures.

Difficulty in Float Movement

Over time, the float may become less flexible or difficult to move, often because the magnetic float gets stained with iron filings or other debris. Emptying the medium and cleaning the float can resolve this issue.

Magnetic Level Gauge (4)

Broken Glass Tube

If the closed glass tube for field indication breaks during transportation or other reasons, it can be replaced with a domestic glass tube, ensuring proper vacuum sealing. Attention should be paid to the vertical alignment of the glass tube to avoid affecting the indicator’s accuracy.

Signal Disturbances

In cases where the output signal experiences frequent disturbances or interference pulses, it’s essential to check the reliable grounding of the signal cable shield and ensure that the resistance meets requirements. If interference persists, using a signal isolator can effectively solve the problem.

BCST Group( ) specializes in the research and development of calibration, pressure, flow, level, temperature, display and other high-performance instrumentation. We have long been trusted by many industries and enterprises such as petroleum, electric power, chemical, pharmaceutical, coal mine, metallurgy and so on. If you are interested in our products, please visit our website to inquire , we will provide you with the best service.

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