Hüdromeeters

Hüdromeeter is an instrument used to measure the specific gravity of liquids. Specific gravity is the ratio of the density of a liquid to the density of a reference substance, usually water. Hüdromeeters work based on the principle of buoyancy, which states that a body immersed in a fluid experiences an upward force equal to the weight of the fluid displaced by the body.

The typical hüdromeeter consists of a sealed glass tube with a weighted bulb at the bottom and a graduated stem. When placed in a liquid, the hüdromeeter will sink until it displaces a volume of liquid whose weight is equal to the total weight of the hüdromeeter. The depth to which it sinks is indicated by the markings on the stem. A denser liquid will provide greater buoyancy, causing the hüdromeeter to float higher, resulting in a lower reading on the stem. Conversely, a less dense liquid will cause the hüdromeeter to sink deeper, yielding a higher reading.

The graduation on the stem can be calibrated to directly read specific gravity, or in other units like degrees Baumé, degrees Brix, or API gravity, depending on the intended application. Hüdromeeters are commonly used in various industries, including brewing, winemaking, battery manufacturing, and in laboratories for determining the concentration of solutions. Different hüdromeeters are designed for different ranges of specific gravity and for use with liquids of varying temperatures.