What is a liquid level gauge? How to choose the type? 【Basic Knowledge】

Why can we tell what's inside the tank from the outside? An explanation of the mechanism and types of liquid level gauges!

■What is a level gauge used for? A level gauge is a general term for devices that allow the liquid level inside a tank or container to be visually observed from the outside. The boundary between gases and liquids, or between different liquids, is called a "level," and a level gauge is an instrument that measures this level. ■Why is it necessary to check from outside the tank? Many tanks and boilers in petroleum and chemical plants are equipment that cannot be directly looked into. Therefore, level gauges that can safely provide information from the outside are essential, and various types exist depending on the application. ■How do the mechanisms differ by type? 1. Float type: Judged by the position of a float that floats on the liquid surface. 2. Glass tube type: Direct visual observation of the liquid level based on the principle of communicating vessels. 3. Differential pressure type: Detects the pressure difference caused by the height of the liquid level. 4. Capacitance type, ultrasonic type, radar type: Non-contact methods that do not touch the liquid. ■Is the choice of method dependent on conditions? While the differential pressure type has a proven track record, its weakness is that it is prone to errors when the density of the liquid changes. On the other hand, the capacitance type can handle harsh environments of high temperature and pressure, as well as high-viscosity liquids. Selecting the appropriate type based on the tank's pressure, size, temperature, and contents is important. Please feel free to consult us first.

Level gauges and level switchesLiquid level control/level switchLiquid Level Sensor