How to choose the rotor density of metal tube rotor flowmeter？

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The working principle of the metal tube rotameter is based on the balance of buoyancy and fluid resistance, where the float (rotor) rises or falls in the fluid flow. Choosing the proper rotor density ensures that it floats correctly as the fluid velocity changes and is not too light or too heavy to provide accurate flow readings.

Media type has an impact on the selection of rotor density, because different types of fluids have different physical properties, including density, viscosity and surface tension. These properties affect the buoyancy of the fluid on the rotor and the resistance to flow through the rotor. In order to obtain accurate measurement results, the density of the rotor needs to match the density of the fluid being measured or be within a specific range.

For example, if the fluid is denser, the rotor also needs to be denser to create enough buoyancy in the fluid to resist gravity. Conversely, for low-density fluids, the density of the rotor should be smaller to avoid excessive floating.

The rotor density of the metal tube rotameter mainly depends on its material. Stainless steel, PTFE and Ti are commonly used. Choose rotor materials for different media types. Gas media generally uses stainless steel rotors, and liquid media chooses whether to use stainless steel, PTFE or Ti material rotors based on viscosity and corrosiveness.